Lignin is a renewable resource with abundant natural reserves, high carbon content, three-dimensional network structure, and a large number of conjugate structures. Carbon materials are a kind of catalyst materials with great application value, especially in the fields of electrocatalysis, thermal catalysis and photocatalysis. The preparation of lignin-derived carbon catalysts with high catalytic activity through precise control of their microstructure characteristics is one of the most effective ways to realize the ultra-high value-added utilization of lignin. The research of lignin-derived carbon catalysts is an interdisciplinary frontier subject involving chemistry, chemical engineering, physics and other disciplines. The controllable preparation of lignin-based carbon catalysts with excellent performance and good stability is still a challenging subject. This article mainly summarizes the recent research of lignin-derived carbon materials, and introduces the application in photocatalysis, thermal catalysis, and electrocatalysis. In addition, the current problems of lignin carbon-based catalytic materials are analyzed, and future development trends and key research directions are prospected.

The environmental problems of chromium and chromium-containing compound pollution have become increasingly prominent, and bioremediation technology has application potential for treating chromium-contaminated sites. In this article, the mechanisms of biosorption, absorption, transformation and Cr(Ⅵ) efflux are analyzed. According to contaminated site conditions, biological removal of Cr(Ⅵ) under multi-factor complex stress is summarized. Meanwhile, metal ions and oxygen anion stresses exert complex effects on cell metabolism and Cr(Ⅵ) removal, which has become the current research hotspot. Besides, progress of Cr(Ⅵ) bioremediation is expounded under combined pollution. Currently, bioremediation of chromium-contaminated sites is undergoing the transition from functional strain screening to detoxification mechanism. The current knowledge can prove the application potential of the core technology of biological removal of Cr(Ⅵ). However, the cost and medium of carrying technique have been bottleneck problems from craft itself to limit bioremediation application, which should be paid enough attention to promote the stable application of bioremediation in future research.

The dissociation constants of methionine in KCl aqueous solutions with the molality of 0.25—4.0 mol/kg at 25℃, 30℃ and 35℃ were determined by changing the pH value, and the protonation enthalpies of methionine species were calculated. Methionine activity coefficients of 0.1—1 mol/kg KCl in 0.025—0.200 mol/kg DL-methionine solution were measured by electromotive force method at 25℃, and the activity coefficients of methionine in KCl aqueous solutions were calculated. The results showed that the dissociation constants of methionine in KCl aqueous solution decreased with the increase of temperature and increased with the increase of KCl concentration. The activity coefficients of methionine in KCl aqueous solutions at 25°C decreased first and then increased with the increase of methionine concentration. Debye-Huckel model and Pitzer model were used to fit the experimental datas of dissociation constants and activity coefficients, and the relevant parameters were obtained. The results show that the reliability of the Pitzer model is better.

The relationship of solid-liquid phase equilibrium in the two ternary systems NaBr-CaBr₂-H₂O and KBr-CaBr₂-H₂O were conducted at 273.15 K by using the isothermal dissolution equilibrium method. The results show that the two ternary systems are of hydrate type. That is, there is absence for double salt and solid solution identified in the equilibrium solid phase. The isothermal phase diagrams of the two ternary systems NaBr-CaBr₂-H₂O and KBr-CaBr₂-H₂O at 273.15 K are composed of an invariant point, two isothermal dissolution curves, and two equilibrium solid phase crystallization regions. The equilibrium solid phases of the ternary system NaBr-CaBr₂-H₂O in the two crystallization regions at 273.15 K are NaBr·2H₂O and CaBr₂·6H₂O, respectively, and the crystallization region of NaBr·2H₂O is much larger than that of CaBr₂·6H₂O. The equilibrium solid phases of the ternary system KBr-CaBr₂-H₂O in the two crystalline regions at 273.15 K are KBr and CaBr₂·6H₂O, respectively, and the crystalline region of KBr is much larger than CaBr₂·6H₂O. Based on the Pitzer model, the reported Pitzer parameters are used to calculate the isothermal solubility of the two ternary systems studied at 273.15 K, and the calculated results are basically consistent with the experimental results.

For the two types of heat sources, open heat source and closed heat source, two heat source temperatures of 423.15 K and 463.15 K were selected, and the none-azeotropic mixed working fluid subcritical organic Rankine cycle (ORC) thermodynamic and thermal economic characteristics were used for simulation analysis. Four thermo-economic indexes are selected, such as levelized energy cost (LEC), area per unit of net power (APR), cost per unit of time (Z) and net power index (NPI). The results show that four thermo-economic indexes are consistent and show same parabolic change trend. With the increase of fluids critical temperature, thermo-economic indexes change regularly. The working fluids selected by the thermodynamic screening criteria have higher thermo-economic performance, indicating that the thermodynamic screening criteria also show high applicability in thermo-economic analysis.

Density functional theory is used to study the adsorption behavior of H₂S molecules on nitrogen-doped Stone-Wales (SW) defected graphene. The adsorption differences of H₂S molecules on SW defect graphene and nitrogen-doped SW defected graphene were analyzed by adsorption energy, differential charge density, Bader charge and electronic density of states. Computation results showed that doping of N atom can improve the interaction between H₂S molecule and graphene sheet effectively, and it can increase the charge transfer between them. The nitrogen atom is mainly used as the bridge for electron transfer between H₂S and graphene surface. H₂S molecules were adsorbed selectively on the hollow of pentatomic carbon of SW defected graphene and nitrogen-doped SW defected graphene, which indicated that the charge distribution of the pentatomic carbon could promote the occurrence of adsorption.

1,3,5-trimethylbenzene is an important chemical raw material and usually exists in reformed heavy aromatics. It is difficult to separate 1,3,5-trimethylbenzene from 1,2,4-trimethylbenzene and 2-ethyltoluene in the C₉ aromatics mixture. The vapor-liquid equilibrium (VLE) data of 1,?3,?5-trimethylbenzene (1)?-1,?2,?4-trimethylbenzene (2) and 1,3,5-trimethylbenzene (1)-2-ethyltoluene (3) were measured at 2 kPa and then correlated by the activity coefficient models NRTL and UNIQUAC. The binary interaction parameters were obtained through regression. The thermodynamic consistency was checked as well. The results showed that 1,3,5-trimethylbenzene and 2-ethyltoluene could hardly be separated at 2 kPa by ordinary distillation. After the alkylation reaction of the ternary system (1,3,5-trimethylbenzene-1,2,4-trimethylbenzene-2-ethyltoluene), single-column and double-column distillation processes at low pressure were used to separate the reaction products by simulation, respectively. Compared to the single-column distillation process, the double-column one presented a better separation performance. The suitable separation parameters were obtained as follows: the number of stages in both columns was 50, and the reflux ratios were 7 and 8 respectively. The purity of 1,3,5-trimethylbenzene could reach 98%(mass) accordingly. This study not only fills in VLE database, but also provides a feasible method for the separation of C₉ aromatics at low pressure.

Developing a high efficiency and low resistance performance heat exchanger is an important way to improve the energy conversion efficiency of the power system, which is of great significance for marine engineering such as shipping industry and offshore oil platform, as well as oil drilling platform and other fields. Inspired by shark gill slit structure, a special-shaped heat exchanger with bionic structures (SSBHX) is designed in this work to greatly release the space and improve the integration of the heat exchanger. By adding four different types of baffles on the shell side of the heat exchanger and introducing “clearance flow” at the inlet, the distribution of flow field, pressure field and temperature field on the shell side of the heat exchanger and the performance difference of the heat exchanger are investigated under various Reynolds numbers between 10000 to 50000 by numerical simulation. The results show that the shell side pressure drop of ladder baffle special-shaped heat exchanger with bionic structures (SSBHX-LA) is about 82% and 65% lower than that of segmental baffle special-shaped heat exchanger with bionic structures (SSBHX-SG), staggered baffle and inlet clearance staggered baffle special-shaped heat exchanger with bionic structures (SSBHX-ST and SSBHX-CST) when the velocity is 0.5 m/s. As the Reynolds number between 15000 and 35000 (0.63—1.46 m/s), the high efficiency and low resistance performance of SSBHX-CST has obvious advantages, which is about 12% higher than that of SSBHX-SG; when the Reynolds number is more than 35000 (v>1.46 m/s), the overall performance of SSBHX-LA is about 5% higher than that of SSBHX-SG, which can be applied to the application environment with higher pressure drop requirements on the shell side. The comprehensive performance evaluation diagrams of heat exchangers under different working conditions are given to provide guidance for practical application and design analysis.

The phase change regenerator based on the high thermal conductivity porous material framework to enhance heat transfer has the advantages of large heat capacity, high heat exchange efficiency, stable temperature control, and strong environmental adaptability. It has a wide range of application prospects in the aerospace field. During the solid-liquid melting process in the porous media, the buoyancy variation derived from the density difference of the liquid phase driven by the acceleration would induce more complex flow and heat transfer instability during the solid-liquid phase change. In this study, an apparatus for studying solid-liquid phase change of the paraffin composited in porous media was set up, and the heat transfer characteristics of paraffin melting in porous graphite under different accelerations were obtained. The results showed that, the temperature of the thermal load can be better controlled by the phase change heat transfer of paraffin composited with porous graphite, and the general heat transfer efficiency and the nonhomogeneous thermal diffusion of the phase change energy storage device were remarkably affected by the accelerating direction. When the direction of acceleration is opposite or perpendicular to the direction of heat flow, the local natural convection of liquid phase driven by acceleration will promote the overall heat transfer efficiency of the phase change energy storage module, while the overall heat transfer efficiency will be suppressed when the direction of acceleration is in the same direction as the direction of heat flow. Besides, the temperature difference under different accelerating direction was enlarged with the increase of the acceleration.

Regulating the particle motions in fluidized bed reactor can realize the enhancement of the reactor performance. Effects of external DC/AC (direct current/alter current) electric fields on particle motions in the fluidized bed with electrostatics were investigated by cold model experiments, and the method of regulating the wall sticking by the external electric field was established. The results showed that the Coulombic force dominated effects of external DC electric fields on particle motions at lower field strength. DC electric fields from the reactor wall to the center weakened the intensity of particle motions and the fraction of axial particle motions, while DC electric fields with opposite directions led to totally opposite results. At higher field strength, polarization forces dominated effects of external DC electric fields on particle motions and it always weakened the intensity of particle motions. Under external AC electric fields, polarization forces still led to the decrease of particle motions without the existing of Coulombic force. However, when the Coulombic force exists, the periodic change of the electric field strength and direction would make the particles oscillate periodically, which increased the intensity of particle motions. Besides, under the experimental operations in this work, external AC electric field can be used to reduce the wall sticking well. The sinusoidal AC electric field of 2.5 kV / cm and 50 Hz could reduce the adhesion of the bed by 76%. The research results can provide guidance for the safe operation and process enhancement of polyolefin fluidized bed reactors.

An X-ray computed tomography (XCT) gas-solid flow parameter measurement system was constructed. The CT 3D reconstruction software was developed based on the cone beam filtered back projection algorithm (FDK), and the jet identification and quantification algorithm was designed. Based on the above method, the influence of bed material particle d_p, the aeration plate orifice diameter d₀, and the aeration plate orifice average area A₀ on jet shape and geometric characteristics at different fluidization gas velocity are obtained. The results show that the average jet length L, the maximum diameter D, and the volume V are inversely proportional to the bed material particle d_p, and directly proportional to the orifice diameter d₀ and the average orifice area A₀. Finally, the correlation equation of the average jet length of the fluidized bed is fitted.

Abnormal interference boiling, that is, mutual interference between different boiling intensities or different boiling modes (nucleus state, film state), has been proven to increase the critical heat flux density of boiling heat transfer in a tiny gap. This phenomenon is realized on the nonuniform plate with alternate distribution of high and low conductance materials. The nonuniform plate with material (PTFE) cross arrangement can increase densities of different materials boundaries and enhance the interacting between different boiling intensities or different boiling modes, which is used to improve the boiling heat transfer characteristics in the micro gap. The experimental results show that the boiling heat transfer performance of PTFE cross arrangement is significantly improved compared with uniform copper plates and PTFE parallel arrangement. The material width and gap size have a significant impact on CHF value of the nonuniform plate. As the gap size increases, the CHF shows an increasing trend and the material width corresponding to the maximum CHF decrease. Under the optimal combination of material width and gap size, the maximum CHF can reach 1140 kW/m² and the highest ratio of CHF enhancement is 84%.

Regarding the visual measurement capability of the wire mesh sensor (WMS), a variety of fluid visualization techniques were used to conduct research and evaluation. Numerical simulation has attracted wide attentions due to its advantages of low cost, flexibility and diversity. However, the research based on transient flow-field and electric-field coupling simulation to investigate the merits of WMS is rarely reported. For the 16×16-electrode conductivity WMS with spatial resolution of 3.125 mm, the flow-field and electric-field coupling principle, which is based on the linear relationship between the local conductivity of measured medium in electric field and phase holdup of fluid, is proposed. Furthermore, the simulations of stratified flow, annular flow and slug flow of gas-liquid flow and corresponding coupling calculations are carried out with the relative interface of COMSOL. And coupling results such as the reconstructed images according to WMS measurements and the current density distribution are in complete agreement with real gas-liquid distribution, which proves the excellent visualized merits of WMS and validates the feasibility of the coupling principle. Besides, the static experiment of air-water stratified flow with different liquid level and corresponding simulations were made. Meanwhile, the WMS measurements were collected respectively. The favorable agreement between reconstructed images derived from normalized WMS measurements with corresponding static flow validates the reliability of the simulation model adopted in this paper. In addition, it also confirms that the normalized processing for the WMS measurements can effectively correct nonlinear mapping between the real fluid distribution and the measurements of “crossing point” around the WMS edges because of edge electric field distortion, which ensures a consistent linear mapping between the two over the entire measured cross-section of WMS.

The fiber probe method and the high-speed photography method are used to test the void fraction distribution in the liquid slug of a vertical upward co-current air-water slug flow. Experiments were performed in a polymethyl methacrylate tube of 15 mm inner diameter. An improved image processing technique based on the machine learning was employed, which can effectively recognize various complex types of bubble boundary. By building a neural network system for bubble boundary extraction, the iterative training of the model was performed by using the constructed bubble boundary database. The radial void fraction distribution profiles of the liquid slugs were obtained and the results showed a typicalwall-peak distribution. The wake effect of the Taylor bubble had aprominent influence on the distribution form, and the wall peaks were observed to correspond to the vortex center of the Taylor bubble wakes. Regarding the local void fraction in the tube center and the radial position of the wall peak, two corresponding predictive correlations were proposed and the experimental data in the present study was found to agree well with the correlations.

The combination of computational fluid dynamics and the population balance model (CFD-PBM) can effectively simulate the fluid behavior in the bubble column, and more accurately predict the flow characteristic, phase holdup and local bubble size distribution. In this paper, numerical simulations of air-water two-phase flow are studied under thermal conditions by using CFD-PBM coupled model in a pressurized bubble column with a 100 mm diameter and 1.3 m height. The system has been investigated in the range of 1MPa, the superficial gas velocity of 0.08—0.24 m/s, and the temperature of 30—160℃. The effect of the superficial gas velocity, temperature and solid content of air-water system on the average gas holdup, large and small bubbles gas holdup, bubble diameter, and bubble size distribution are discussed. The results show that the simulation results of the average gas holdup are in good agreement with the experimental values within the error range of 10%. The temperature change mainly affects the coalescence and breakage of bubbles in the tower, and the coalescence and breakage mechanism is used to explain the influence of temperature on the fluid behavior.

At present, most renewable energy sources such as solar energy have intermittent and unstable problems, so high efficiency heat storage technology has become a key way to develop solar energy. Metal hydride high temperature heat storage technology, as one of the most promising methods of thermochemical heat storage, has been widely concerned. To realize the engineering application of metal hydride high temperature heat storage technology, it is necessary to investigate the transfer mechanism with hydrogen thermal coupling. In this paper, a multi-physical model of the reactor was established, and the variation law of the reactor parameters was obtained. By discussing the distribution of bed temperature and reaction fraction, the heat output of the reactor was divided into three stages: initial stage, platform stage and decline stage. At the same time, taking the peak point as the boundary, the initial stage can be divided into the initial rising stage and the initial descending stage. And the formation and movement mechanism of reaction front and the formation mechanism of inhomogeneous reaction were obtained. It can be concluded that hydrogen pressure, thermal contact resistance and bed thermal resistance are the control steps of corresponding stages. In addition, the variation of reactor parameters was obtained under different hydrogen pressure, thermal contact resistance and bed thermal resistance. Through comparative analysis, it was found that hydrogen pressure was the main parameter to regulate the maximum output temperature of the reactor. Compared with the thermal contact resistance, the bed thermal resistance showed more obvious effect on the heat output of the reactor. Finally, it was pointed out that to realize the engineering application, improving the thermal conductivity of the bed was the most promising choice to enhance the performance of metal hydride high temperature heat storage system.

The inner condenser for electric vehicle (EV) heat pump system of the three heat exchangers type was experimentally studied, it was found that the heat transfer capacity difference between the double-layer four-pass condenser and the single-layer two-pass condenser was as high as 7.9%, under the same overall dimensions, and corresponding pressure drop difference of refrigerant side was 177.6%. A one-dimensional simulation model of the double-layer four-pass inner condenser was established to investigate its thermal-hydraulic performance under different structural parameters with refrigerant R134a as well as R1234yf. The simulation results showed that, pressure drop of refrigerant side decreased significantly when the pass arrangement is 11-12-12-11 when the refrigerant was R134a, while the heat transfer capacity was insensitive to the pass arrangement. When the thickness of the second layer of the double-layer condenser was fixed and the thickness of the first layer increased from 10 mm to 20 mm, the heat transfer rates of R134a can be increased by 10.4%, however, pressure drop can be decreased by 63.6%, under the conditions of high air flow rate. When the total thickness of the double-layer condenser was fixed, two thicknesses combinations of the first layer and the second layer as 16 mm-8 mm and 14 mm-10 mm could achieve better overall thermal-hydraulic performance, and the difference of heat transfer rate can be negligible. Under the airflow rate of 732 m³/h, the condenser of the thickness combination of 14 mm-10 mm reduced the pressure drop by 35.19% for R134a, compared to the one of 10 mm-14 mm. When the refrigerant is R1234yf, the heat exchange and pressure drop are reduced by 8.02% and 47.0% respectively compared with R134a.

The uneven distribution of refrigerant between the heat exchange tubes of the evaporator will result in a decrease in its refrigeration capacity. Three-dimensional models of shell and tube evaporator and splitter plates were established. The effects of splitter plate position, aperture, number and opening structure on R410A flow distribution performance were simulated. The results show that the parameters of splitter plate have a significant effect on uniform distribution of refrigerant. Under different inlet flow rate conditions, the unevenness declined with the movement of splitter plate to the inlet of evaporator, and the decrease rate gradually slowed down. The unevenness increases with the diameter of aperture, decreases with the number of opening and reaches stability. After optimizing the opening structure of the splitter plate, the average performance of the upper and lower smallhole can be increased by 21.4% compared with the equal round hole structure. The evaporator flow distribution experimental platform was built. The flow distribution law obtained from simulation and the improvement of flow evenness performance with splitter plate were verified by experiments. Which illustrate that optimizing the opening structure of splitter plate according to characteristics of flow distribution can effectively improve the effect of refrigerant evenness.

Based on the cooling heat transfer in the air-kerosene heat exchanger for aero-engine applications, numerical studies on the heat transfer of supercritical-pressure RP-3 aviation kerosene in vertical U-turn circular tubes have been carried out. The heat transfer characteristics and heat transfer mechanisms of the inlet vertical section, the bend section, and the outlet vertical section were explored. The influence mechanisms of operating pressure and heat-mass ratio on heat transfer were analyzed. The results show that the inlet vertical section presents the characteristic of uniform heat transfer. The centrifugal force in the bend section leads to the abnormal stratification of fluid temperature, the uneven circumferential density distribution, and the lateral unbalanced kinetic energy, thus induces the strong secondary flow phenomenon. The maximum secondary flow velocity reaches 0.45 m·s^-1. The heat conduction process in the solid region is also affected, and the abnormal stratification of solid temperature is observed. The combined effect results in the circumferential differences in inner-wall temperature and heat flux. The circumferential heat transfer difference in the outlet vertical section still exists, and the secondary flow is weakened. Increasing the operating pressure or reducing the heat-mass ratio, the thermo-physical properties with more moderate variations in tube cross sections, and the difference in circumferential heat transfer is weakened.

Supercritical carbon dioxide (S-CO₂) power cycle has a broad application prospect in the field of energy utilization, in which the heat transfer of supercritical CO₂ plays a significant role in its energy conversion efficiency. Therefore, an experiment has been conducted to determine the convective heat transfer characteristics of supercritical CO₂ flowing in a mini horizontal circular tube, and a BP neural network optimized by genetic algorithm has been established to predict the heat transfer coefficient of supercritical CO₂ under different conditions. The experimental parameters are as follows: system pressure 7.5—9.5 MPa, mass flux 1100—2100 kg/(m²?s), heat flux 120—560 kW/m². The experimental results show that the heat transfer coefficient of supercritical CO₂ increases first and then decreases with increasing fluid temperature, and reaches maximum near the pseudo-critical temperature. The model of the GA-BP neural network can effectively predict the heat transfer coefficient of supercritical CO₂, the determinate coefficient of predicted data R² is 0.99662, and more than 95% of the data are within the error range of ±10%, the average error is 3.55%. GA-BP neural network model provides a novel idea for heat transfer prediction for supercritical fluids.

2,5-Furandicarboxylic acid (2,5-FDCA) is a monomer of biodegradable plastic polyethylene furanoate and will be in huge demand in the near future. In order to solve the problem of lower yield in the preparation of 2,5-furandicarboxylic acid during cyclodehydration of hexaric acid, higher selective catalytic systems were explored in this paper. HBr-MgBr₂ and HBr-LiBr were found to have excellent catalytic ability for cyclodehydration of hexaric acid. 2,5-FDCA yield of 84.2% was achieved for potassium bisaccharate cyclodehydration catalyzed with 3%(mass)HBr-6%(mass) MgBr₂ at 120℃ and 2 h reaction time. The molar yield of 2,5-FDCA remained above 80% when substrate concentration was up to 5%(mass) and actual water concentration was enriched from 3.3% to 16.5%. The kinetics of cyclodehydration of potassium bisaccharate to 2,5-FDCA at temperatures from 100℃ to 130℃ were measured with 3%(mass) HBr-6%(mass) MgBr₂. The activation energy of 2,5-FDCA formation was 108.9 kJ/mol and that of by-product formation was 136.6 kJ/mol by first-order kinetic fitting. The research work has played a positive role in promoting the industrialization of 2,5-FDCA route by dehydration and cyclization of hexadecanoic acid.

Five kinds of Mo modified Mo-Fe composite catalysts were synthesized by introducing Mo into the precipitation, oxidation and drying stages of Fe catalyst preparation, by which the binding forms of Mo and Fe could be regulated. The catalysts were characterized by XRD, SEM, TEM, BET, XRF, XPS and H₂-TPR. The Shenhua Shangwan coal hydroliquefaction experiment was carried out in a 500 ml autoclave. The results show that the synergistic effect of Mo and Fe promoted the activation of hydrogen and the decomposition of coal, and the activities of Mo modified composite catalysts for direct coal liquefaction were significantly improved. The high distribution of Mo on the surface is beneficial to the transfer of active hydrogen from solvents to asphaltenes, and promotes the conversion of asphalt into oil. Mo co-precipitation with Fe affected the crystal growth of iron-oxygen compounds, with the decrease of the grain size, and the increase of the specific surface area and reducibility. Mo-Fe compound synthesis by introducing Mo into ammonia solution, with uniform distribution of Mo, showed high catalytic activity and the yield of liquefaction oil increased by 4.4%. The impregnation of Mo into Fe-based catalyst did not change the structure of iron-oxygen compound, but the enrichment of Mo on the catalyst surface increased the collision probability with reactants, and the yield of liquefaction oil increased by 5.0%.

H₄EDTA, H₂Na₂EDTA and NaOH aqueous solutions were used to modify the original NaY zeolite separately by acid-base modification and continuous acid-base modification, and the corresponding CuY catalyst was prepared by the liquid-phase ion exchange method. The N₂-physisorption, TEM, XRD, ²⁹Si NMR, ²⁷Al NMR, NH₃-TPD, Py-IR, ICP, XPS and CO-FTIR were used to characterize the structure of the support and catalyst. The effect of mesoporous construction in NaY zeolite on catalytic performance of CuY for oxidative carbonylation of methanol was investigated. The results indicated that partial framework Al of NaY zeolite were extracted after sole treatment by H₄EDTA, with the formation of extra-framework Si and Al species, and the obtained E-NaY did not form obvious mesoporous. Extra-framework and partial framework Al of E-NaY zeolite were removed after acid washing by H₂Na₂EDTA, and the obtained EW-NaY generated obvious mesoporous. The extracted Al species were reinserted back into the framework of zeolite accompanied with desilication during alkali treatment of E-NaY and EW-NaY by 0.2 mol/L NaOH, and abundant mesopores were formed in the obtained E0.2AT-NaY and EW0.2AT-NaY zeolite. Moreover, the utilization of exchanged sites for Cu⁺ accessible to reactants for EW0.2AT-NaY attained the maximum due to the highest mesopore volume (0.45 cm³/g) and abundant Al-defects structure. Nevertheless, the number of exchanged sites for Cu⁺ (66 μmol/g) accessible to reactants was significantly less than that of E0.2AT-NaY (176 μmol/g) due to higher dealumination degree of EW0.2AT-NaY than that of E0.2AT-NaY. Consequently, the number of Cu⁺ active sites and catalytic activity for EW0.2AT-CuY were just slightly lower than that for E0.2AT-CuY, and the catalytic activities for both were about 2.2 times as that of the pristine CuY catalyst.

When the urea-selective catalytic reduction technology runs at low temperatures, urea is not completely decomposed, and it is easy to form by-products such as biuret, cyanuric acid and melamine. In this study, TiO₂ catalyst was combined with dielectric barrier discharge plasma for hydrolysis of urea decomposition by-products with or without O₂ in the carrier gas under temperature-programmed conditions. Experimental results show that biuret, cyanuric acid and melamine over TiO₂ could be hydrolyzed to NH₃ and CO₂ at 43—261℃, 217—300℃ and 199—300℃, respectively. The presence or absence of O₂ in the carrier gas hardly affects the catalytic hydrolysis process. Introducing plasma significantly decreases the hydrolysis temperatures of biuret, cyanuric acid and melamine. Insignificant variation of NH₃ yield and small amounts of N₂O and NO by-products are observed when plasma is applied in the O₂-free carrier gas. In the O₂-containing case, NH₃ yield obviously decreases while more N₂O, NO, NO₂ and small amounts of NH₄NO₂ and NH₄NO₃ are generated by applying plasma. To overcome drawbacks of the plasma-enhanced process, mainly the formation of by-products, further work is required in the future, such as optimizing discharge conditions and catalyst compositions.

The synthesis of 1,4-butynediol by the condensation of formaldehyde and ethynyl is an important reaction in ethynyl chemical industry. The study on catalytic mechanism and evolution of Cu-based catalysts in the acetylene reaction of formaldehyde has attracted more and more attention. In this work, on the basis of the preparation of copper silicate catalyst and the performance of formaldehyde ethynylation in the previous stage, and further through the adjustment of the heat treatment temperature, when the calcination temperature is 650℃, a CuO nanocrystalline catalyst confined in the SiO₂ network structure was constructed. Due to suitable chemical environment of CuO nanocrystals, cuprous ethynylation is formed rapidly in the initial stage of the formaldehyde ethynylation reaction, and the yield of about 80% of 1,4-butynediol is obtained. The initial activity is higher than that of the same kinds of catalyst. More importantly, the catalyst showed good stability due to the confined effect of the SiO₂ network structure. The yield of 1,4-butynediol was almost unchanged in 6 application experiments, showing good stability.

The printing and dyeing sludge contains a large amount of metal-based components. In order to explore the synergistic effect of metal base components in sludge ash during pyrolysis process, the main metal oxides contained in the ash of textile dyeing sludge were selected, and the catalytic pyrolysis experiments were carried out after the addition of single component and multi-component respectively. The effects of these metal-based components in the ash on the catalytic pyrolysis of the textile dyeing sludge was analyzed by X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS) and thermogravimetric mass spectrometry (TG-MS). The results showed that each metal-based component exhibited their temperature range and catalytic performance during pyrolysis. Moreover, the synergistic effect on pyrolysis is the combined effect of Fe₂O₃, ZnO, CaO and Na₂CO₃. Further, the synergistic effect can be divided into two stages: 250—500℃ was the main pyrolysis zone, and each metal-based component plays the role of catalyst to promote the pyrolysis of macromolecular compounds. In the pyrolysis zone after 600℃, Fe₂O₃ and other components can react with the carbon in the raw material, resulting in a significant weight loss peak in the thermogravimetric curve, which further improved the cracking characteristics of the residue.

Based on the “ligand-induced interfacial growth” strategy, NM88(D)/COF-OMe composite with excellent photo-Fenton degradation performance and photo-stability towards sulfamerazine (SMR) was constructed. The morphologies and photoelectric properties of the materials were characterized and the results showed that: the anchoring of DMTP induced the formation of a tightly connected hetero-interface inside the composite, improved the dispersion of COF-OMe on the surface of NM88(D), the specific surface area, visible light absorption and photogenerated carrier separation capacity. As a consequence, the photocatalytic ability of the composite was enhanced. The results of the composite catalytic performance measurements showed that the apparent rate constant of NM88(D)/COF-OMe was 0.0658 min^-1, which was significantly higher than that of the pristine materials and other reported catalysts. The catalytic activity of the composite remained more than 95% after 10 cycles of degradation, indicating that the NM88(D)/COF-OMe possessed superior structural stability. Finally, the catalytic mechanism for the degradation of SMR by photo-Fenton of the composite material is deduced. The excellent catalytic ability of NM88(D)/COF-OMe is attributed to the existence of heterogeneous interface, which improves the separation efficiency of photogenerated carriers and promotes the high efficient generation of hydroxyl radical (·OH). The current study offered a promising strategy for developing high performance photo-Fenton active MOF/COF composites formed by the “ligand-induced interfacial growth” strategy for a range of practical applications.

The impact of CO₂ on the climate is getting more and more serious. Converting it into formic acid can simultaneously realize resource utilization and carbon emission reduction. The current research of CO₂ hydrogenation to formic acid is mainly to find high-performance catalysts, and process design is also indispensable for the industrialization of formic acid, but the process design of CO₂ electrocatalytic hydrogenation to formic acid has not been reported yet. Using natural gas whose main components are H₂ and CO₂ to produce hydrogen pressure swing adsorption desorption gas as raw materials, a process of gas membrane separation coupled with CO₂ electrocatalytic hydrogenation to produce 30000 t of formic acid per year was designed and simulated in Unisim Design process simulation software. Then the sensitivity analysis method was used to optimize the membrane electrode area, cathode potential, H₂ membrane area, CO₂ membrane area, distillation column pressure and reflux ratio. The unit cost of formic acid under the optimal scheme is 6.37 CNY/kg, which is 31.88% higher than the traditional Kemiral-Leonard (KL) process, but the proposed process can reduce 33300 t CO₂ per year, which has important environmental significance. Finally, through cost analysis, three effective solutions are proposed from the three aspects of reactor life, cost and electricity price, which can reduce the production cost of formic acid to that of the traditional KL process.

UTSA-280 is a typical molecular sieving metal-organic framework (MOF) for separating CO₂ from CH₄ or N₂, but the traditional solution-based synthesis method usually receives MOF particles with considerable size. Here an alternative mechanochemical way was used to fabricate small sized UTSA-280 particles, which was subsequently acted as filler materials in the polysulfone (PSf) based mixed matrix membranes (MMMs) for natural gas purification and CO₂ capture in flue gases. It shows that the introduction of UTSA-280 filler in the PSf matrix not only accelerates the transmission of CO₂ but also boosts the mixed gas separation factor of CO₂/CH₄ and CO₂/N₂. When the filler loading was 30%(mass) the CO₂/CH₄ and CO₂/N₂ separation factor were 56.39 and 53.17, respectively, and the CO₂ permeability was 18.61 Barrer, compared with pure membrane, the CO₂/CH₄ and CO₂/N₂ separation factor and CO₂ permeability showed 47.3%, 63.5% and 128.9% enhancement ratio, respectively, thus breaking the "trade-off" limitation. By introducing this specific MOF with molecular sieving character, the MOF based MMMs can improve the permeability of CO₂ as well as gas separation performance, which is of great significance to the purification of natural gas and the capture of CO₂ in flue gas.

Nitrous oxide (N₂O) is the third largest greenhouse gas after CO₂ and CH₄, and its capture has the dual value of resource recovery and greenhouse gas emission reduction. In this paper, MIL-101(Cr) with different anion terminals were synthesized by adding hydrofluoric acid and hydrochloric acid separately, named MIL-101(Cr)-F and MIL-101(Cr)-Cl, the synthesized samples were characterized by XRD, BET and SEM, et al. Single component adsorption isotherms of N₂O and N₂ were tested, and the selectivity of N₂O/N₂ and corresponding adsorption heat of gases were also calculated. Additionally, the simulation of mixture (N₂O/N₂=0.1%/99.9%) breakthrough were carried out. As the result, MIL-101(Cr)-Cl with the highest N₂O adsorption capacity (6.43 mmol/g, 298 K) and N₂O/N₂ selectivity (267) were reported. Furthermore, the simulation result confirmed that MIL-101(Cr)-Cl has great potential to capture trace amount of N₂O.

Alkenes are important raw materials in chemical industry. Adsorption separation technology can achieve alkene purification under mild working conditions. Adsorbent of alkane selectivity is the key to achieve effective chemical separation processes. With the help of molecular simulation, we proposed the mechanism of tuning ethane/ethylene selectivity by controlling pore size. Porous carbon adsorbents with distinct average pore size, showing ethylene and ethane selectivity, were prepared via different activation processes. The experimentally validated mechanism suggests that: (1) Graphene surface is ethane-selective; (2) Porous carbon undergoes the reversed selectivity of ethane-ethylene-ethane with the increase in its pore size. This mechanism can be applied to porous carbon of different pore shapes. Hence, effective alkane-selective adsorbent can be obtained by amplifying the alkane-selective feature within the confined micropore of the porous carbon adsorbent.

The novel multi-rotor gas-liquid vortex separator can realize the high-efficiency separation of gas-liquid cyclone in the large-diameter separator. The inlet vortex head is one of the critical components of the separator. The droplet size distribution and the pre-separation performance of the vortex head were investigated in a large-scale cold separator model. The initial droplet size distribution is rapidly redistributed under the high-speed airflow in the straight inlet pipe. The redistribution feature is similar to the Gaussian distribution with the Sauter mean diameter (SMD) is 16.8 μm. The droplets move stably in the straight inlet pipe with H/D = 2.47—8.48 at the gas velocity of 16.95 m/s, and the particle size distribution does not show apparent changes. At high gas velocity, the combined action of the shear effect and wall effect increases SMD slightly. The droplet size distribution changes significantly when the droplets flow through the vortex arms, showing the “double peak”. The impact of the vortex arms on the droplet aggregation is noticeable. Based on the particle size distribution analysis, the droplet characteristics at the end of vortex arms are obtained. It is found that the pre-separation performance of the vortex head is superior. When the pressure drop is only 3.2%—8.4% of the total pressure drop, the separation efficiency can be 42.8%—62.5% of the total separation efficiency. The inlet swirl head structure can not only create a strong swirling initial separation environment for the mixed phase, but also realize the inertial pre-separation of the mixed phase with its own structural characteristics.

Hydrogen mordenite (H-MOR) zeolite molecular sieve is an efficient catalyst for the carbonylation of dimethyl ether (DME) to methyl acetate (MA). The modification of pyridine can effectively improve its stability and catalytic life. In order to study the essential mechanism of pyridine modification on the atomic scale, based on Monte Carlo and molecular dynamics simulations, this paper analyzes the main reactants CO, DME and products of carbonylation in the periodic models of H-AlMOR and Py-H-AlMOR, respectively. The adsorption-diffusion behavior of MA has been systematically compared. The results show that the introduction of pyridine will reduce the adsorption capacity of the main reactants CO and DME in the H-MOR molecular sieve to a certain extent (24%—33%), but it helps to improve the adsorption balance of the two in the molecular sieve and increase the concentration of reactants in the active channel 8-MR. At the same time, the introduction of pyridine will have a greater impact on the diffusion of various molecules (21%—58%), especially the diffusion performance of the product MA decreases by about 58%. In addition, the introduction of pyridine can also reduce the high feed ratio P_CO/P_DME required to achieve high reactivity.

As an important quality indicator of crystalline products, crystal morphology could have major impact not only on such quality measures as solid flowability, stability, dissolution rate and bioavailability, but also on downstream operations such as filtration, drying, and tableting. In this work, molecular simulation was used to guide the selection of additives in the cooling anti-solvent crystallization process of aspirin. The additives were used as crystal morphology modifiers to reduce the aspect ratio of aspirin crystals in order to optimize the crystal morphology. The effects of additive concentration, seed crystal addition, cooling rate, stirring rate and water addition rate on the morphology, flowability and particle size distribution of aspirin crystal products were examined to determine the appropriate experimental conditions. The experimental result showed that the addition of polyvinylpyrrolidone (PVP) as an additive can reduce the aspect ratio of aspirin crystals and obtain short prismatic crystal products, which can significantly change the crystal morphology and optimize the flowability of the product.

The mass transport of mixed solutes in a standard 8-inch spiral wound reverse osmosis (RO) membrane element for coal mine water desalination was simulated by using computational fluid dynamics (CFD). A calibrated Archimedes spiral curve was used to represent the trajectory for the feed flow in the model. Coal mine water was simulated as a liquid with mixed inorganic salts. The interactions between ions were incorporated into the model by using a mixed salts osmotic pressure model. The simulation results showed that the flow velocity along the cross-section was less than 1% of the axial flow velocity and, as such, can be neglected. A simplified geometry was used in the subsequent simulations of this work. At the investigated operating conditions, the feed spacer contributed to 86% of the pressure drop, however its presence resulted in a decrease in the concentration polarisation (CP) of Na₂SO₄ from 3594 mg/L to 2036 mg/L where the most significant CP occurred. In addition, with the presence of the feed spacer, CP mainly occurred in the limited areas at the back of the feed spacer. The simulated effluent flowrate was compared with both experimentally measured results and simulated data using ROSA9.1 with less than 5% error obtained for both cases, indicating the high accuracy of this CFD model for simulating the mass transfer of mixed salts in full-scale spiral wound RO elements during filtration processes. Compared to commercial design software such as ROSA (Reverse Osmosis System Analysis) which only provides information on salt concentrations in permeate and brine streamse, the model developed in this work can provide information on concentration polarisation profiles and provide insights into the extent of fouling potential on different locations on a spiral would module.

The integration of inter-plant hydrogen systems is of great significance to rationally configure the network structure and allocate hydrogen resources in chemical industry parks. For the optimal design of hydrogen network in chemical industry park, a three-step approach was proposed to design the inter-plant hydrogen network under multi-period operations. In the proposed method, an optimal design model for the inter-plant hydrogen network under single period operation was solved to obtain the hydrogen utility exchanged under each subperiod. Then, an optimization model for multi-period hydrogen network in a single plant was adopted to optimize the hydrogen network in each plant. Finally, an optimization model for inter-plant hydrogen network under multi-period operations was used to determine the final hydrogen network structure and scheduling scheme of inter-plant hydrogen system. The results showed that the proposed method can be used to effectively solve the integration problems of inter-plant hydrogen network under multi-period operations. A better inter-plant hydrogen network under multi-period operations can be obtained without increasing the complexity of the hydrogen network. In addition, the solving efficiency can be greatly improved.

Production operations of modern chemical processes record a large amount of process control manipulating temporal data. How to extract valuable manipulating experiences and rules is of great significance to enhance process operation intelligent level. Previous research results have shown that time series clustering is an effective method for mining historical control manipulating sequences. However, practical working conditions often deviate from the historical data, making it difficult to reconstruct accurate process control manipulating strategies. In response to this problem, this paper proposes a process control manipulation extraction method based on deep learning of data fragmentation, using agglomerative hierarchical temporal clustering based on Levenshtein distance to obtain different process disturbance state classes, extracting corresponding effective manipulating sequences for fragmentation, and employing convolutional neural networks for deep learning and reconstructions of manipulating strategies. The approach is demonstrated by industrial heat exchanger processes, in which, the experiment shows that the proposed approach is able to overcome the poor adaptability and strong dependence on data sources of conventional control manipulating sequence mining methods in practical applications, achieving satisfactory results.

The low-rank coal clean conversion polygeneration system based on the three-tower circulating fluidized bed (TBCFB) is expected to improve the energy and resource utilization efficiency of low-cost coal. The process simulation software Aspen Plus was used to simulate and verify the methanol synthesis route of the polygeneration system. To improve the energy efficiency, the self-heat recuperation theory was applied to the unit of rectisol and methanol distillation. And then, the heat exchange network (HEN) was designed based on this self-heat recuperation process. The results demonstrated that the self-heat recuperation process was beneficial to the enhancement of energy utilization. Compared to the conventional process, the self-heating regeneration process saves 29.4% in the cold utility of the low-temperature methanol washing unit and 25.8% in the total energy consumption; the cold utility in the methanol distillation unit saves 69.5% and the total energy consumption 32.3%.

Galectin-10 (Gal10) exists in human eosinophils and can undergo phase transformation into crystals to induce asthma. The molecular interactions between Gal10 protein and antibody were investigated by molecular dynamics simulation combined with molecular mechanics-Poisson Boltzmann surface area free energy decomposition. It is found that the binding of antibody on Gal10 protein was mainly driven by hydrophobic interaction. The most favorable amino acid residues for binding were Y69, K117, D113, E68, I116, H114 of Gal10 protein and W53-H, Y104-H, N97-L, K55-L, Y93-L, R100-H of antibody. Then an affinity combination model for the molecular interactions between Gal10 protein and antibody was proposed. A sequence WXYXXNXY was then designed for constructing a library of inhibitors, followed by the screening using molecular docking, molecular dynamics simulation, conformational comparison, etc. Finally, WGYGWNGY was obtained and identified as a potentially effective asthma inhibitor.

The effect of the aggregation state of the ionic liquid 1-octyl-3-methylimidazole bromide([C₈mim]Br) additives on the protein crystallization process was studied. Hen egg white lysozyme was chosen as the model protein and [C₈mim]Br was applied as the additive. It was found that the presence of [C₈mim]Br could improve the crystal morphology as well as affect the number and size of crystals. The influence mechanism of ionic liquid [C₈mim]Br on the crystallization of lysozyme was revealed by measuring the solubility, crystallization kinetics, aggregation state and zeta-potential at different [C₈mim]Br concentrations. The results showed that the interaction mechanism between lysozyme and [C₈mim]Br varied with the aggregation states of [C₈mim]Br. When the concentration of [C₈mim]Br was low (< 0.1 mol/L), there was hydrophobic interactions between [C₈mim]+ and lysozyme molecules, which promoted the aggregation and crystallization process. When the concentration of [C₈mim]Br was high (> 0.1 mol/L), [C₈mim]+ self-aggregated into micelle and formed aggregate complex with lysozyme molecules. The results from DLS further showed that the lysozyme-micelle complex was the basic unit in nucleation and hence, a slower crystallization rate and a higher crystal quality were obtained.

In order to improve the stability of lipase and construct a new immobilized lipase catalytic system, the core-shell hydrophobic magnetic organosilica nanoparticles (MMOSNs) with superparamagnetic Fe₃O₄ core and dendritic fibrous silica shell were synthesized through an improved Winsor Ⅲ microemulsion dual continuous phase system, and the obtained MMOSNs were employed as support for the immobilization of Candida antarctica lipase B (CALB). After the optimized conditions, the CALB load was 177.49 mg/g, and the specific hydrolysis activity was 27390 U/g. The CALB@MMOSNs could effectively activate the interfacial activity of CALB and protect the active conformation from external environmental harm through hydrophobic interaction with CALB molecules and its surface pore structure, showing better activity and stability than free enzyme and magnetic inorganic silicon immobilized CALB. In addition, CALB@MMOSNs could catalyze the esterification of levulinic acid with lauryl alcohol, and the highest conversion rate reached 85.05%. After repeating the reaction for 9 cycles, the conversion rate remained 68.94%, while the commercial N435 retained only 29.83%. These results indicated that the core-shell hydrophobic magnetic organosilicon is a good support for immobilized CALB, which can effectively expand the application of lipase in industry.

Water-in-oil emulsion is a newly emerging hydration enhancement material in recent years. It has good hydration and gas storage potential. However, in order to ensure the stability of emulsion, the water content of the water-in-oil emulsion usually does not exceed 50%. The gas storage capacity of hydrate is closely related to the water content. Therefore, high water content water-in-oil emulsion has more application prospects. In this study, a water-in-oil emulsion with water content of 55% was produced and the methane hydrate formation experiment was carried out by using the emulsion. The effects of the amount of emulsifier, initial pressure, stirring rate and cyclic capacity were investigated. The results show that the increase of water content will lead to the increase of emulsion droplet and the decrease of gas storage when the water content is more than 55%. The water content of the emulsion is 55% with 5%(mass) (based on water content) of Span80 / Tween80 (m_Tween80∶m_Span80=0.783∶1) emulsion is the best emulsion for storing CH₄. The increase of initial pressure is beneficial to the improvement of hydrated gas storage performance. However, too high pressure will lead to the rapid formation of hydrate shell and thus reduce the overall gas storage capacity. The appropriate stirring rate is conducive to hydrate formation. The optimal emulsion hydration and gas storage conditions were temperature of 274.15 K, gas-water volume ratio in the reactor of 10∶1, methane initial pressure of 6 MPa, and stirring rate of 700 r/min. In this condition, the gas storage capacity was 141.42 L gas/L water; further four-cyclic gas storage experiment proved that the emulsion had good recyclability, which cyclic gas storage capacity is above 130 L gas/L water. The research results can provide technical supporting for natural gas storage and transportation and hydrocarbon-containing mixed gas separation.

Coal chemical industry plays an important role in national economy of China. Currently, coal chemical wastewater is usually treated by chemical oxidation and biochemical oxidation to remove the organic matter, followed by reverse osmosis (RO) to get the recycled fresh water. The concentrate is subsequently evaporated, while the generated mixture of salts and organic matter belongs to hazardous waste, which is costly to be treated and not environmentally friendly. With the increasing requirements of environmental protection, fractional crystallization has been developed to solve this problem. However, organic matter significantly inhibits salt crystallization. Consequently, there is considerable interest in removing the organic matter of coal chemical RO concentrate efficiently and economically. The cost of advanced oxidation treatment is higher, while it is hard to conduct microbiological treatment in such wastewater since it is weak in high salinity and concentrated toxic compounds. In the work reported here, coal chemical RO concentrate contained 50.9 g/L of TDS and 233.4 mg/L of TOC (total organic carbon) with BOD₅/COD of 0.05. Nine halotolerant bacteria strains were successfully isolated from different sludge and soil, which belonged to Pseudomonas sp., Bacillus sp., and Halomonas sp.by16S rDNA identification. Meanwhile, the research has studied physiological and biochemical characteristics of these nine strains. The results showed that the strains can grow well at 0—15% salinity. Ozone oxidation pretreatment and halotolerant bacteria preparation (mixture of nine strains) treatment was used to treat the wastewater. After one month's continuous operation, the TOC removal ratio reached 40%, reflecting an advanced level compared to the previous study. According to GC-MS (gas chromatography-mass spectrometer) analysis, ozone oxidation can destroy the cyclic structure of organic matter and improve the TOC removal ratio of subsequent halotolerant bacteria preparation. This work provided an effective approach to degrade coal chemical reverse osmosis concentrate by microbial method.

The VMoTi/glass-fiber catalytic filter-cloth (VGCF) with denitrification (DeNO_x) and dust removal (Dedust) function was prepared by impregnation method, and NO_x and dust removal performance of VGCF was systematically studied. The effects of catalyst-loading, binder, reaction temperature, filtering velocity, SO₂ and H₂O on the performance of DeNO_{xand Dedust were investigated, combined with SEM, XRD and EDS characterization methods. It was found that the DeNOx efficiency is 60%—85% at 200—250℃ when the loading capacity was 130 g/m² and the filtering velocity was 0.5 m/min. Further, after 500 times of pulsing aging, the DeNOx efficiency is basically unchanged, indicating good stability of DeNOx. After adding SO2 and H2O, the DeNOx efficiency is maintained at more than 75%, showing great resistance to SO2 and H2O. The dust removal efficiency of VMoTi/glass fiber composite catalytic filter cloth is above 99.99%, which meets the requirements of actual industrial smoke and dust treatment applications.}

The contents of total chlorine, inorganic/organic chlorine and volatile/non-volatile chlorine in municipal solid waste (MSW) components were determined by the oxygen bomb method, extraction-oxygen bomb method and tube furnace-oxygen bomb method, respectively. Based on which, the speciation of chlorine in MSW and its transformation during thermal treatment of MSW were investigated. The results show that the contents (dry basis) of total chlorine in the MSW components range from 1.52 mg/g to 19.44 mg/g, of which the contents of chlorine in the food waste components are the highest, 8.38—19.44 mg/g, followed by the rubber/plastic components, 3.51—10.60 mg/g. The higher chlorine contents in some paper and textile components are related to the cross-contamination by food waste, while the contents of chlorine in the other components are lower. Source separation of food waste can significantly lower the chlorine content in MSW. The inorganic chlorine accounts for more than 90% of the total chlorine in the food waste components, while the organic chlorine accounts for 46%—55% of the total chlorine in the rubber/plastic components. The content and speciation of chlorine in different components of MSW from different transfer stations vary greatly, which indicates the complexity of chlorine occurrence in MSW. During thermal treatment, about 65% of chlorine in the rubber/plastic components and 59%—71% of chlorine in the paper components are transformed to volatile chlorine under air atmosphere, respectively. Under nitrogen atmosphere, the non-volatile chlorine in the food waste components accounts for 38%—69%, the volatile chlorine in the rubber/plastic components and paper components accounts for 42%—60% and 56%—71%, respectively. The inorganic chlorine tends to be converted into volatile chlorine and non-volatile chlorine under air atmosphere, and into non-volatile chlorine and other chlorine compounds under nitrogen atmosphere; while the organic chlorine is mainly converted to the volatile chlorine. It can provide theoretical basis and solution for flue gas cleaning and chlorine corrosion prevention during thermal treatment process of MSW by revealing the occurrence of chlorine in MSW and its transformation during thermal treatment.

Biomass pyrolysis and gasification can realize the efficient and clean utilization of carbon-based renewable energy. In order to predict yield distribution of compositions and achieve the closest of biomass pyrolysis and gasification, the comprehensive calculation method has been improved through genetic algorithm (GA) method with tested data of biomass pyrolysis and gasification. Aspen Plus model has been established consisting of pyrolysis stage and gasification reactions of fixed carbon according to GA-comprehensive calculation method. The results show that the optimum ratio coefficient of O for husk (dry basis) transferring to CO₂ equals 32.02% in the GA-comprehensive calculation method, and the optimized yield ratio for tar (R_tar) is 8.32% of the volatile with the mean pyrolysis component error of 8.53%, while the mean gasification component error of 5.37%. As for Aspen Plus model based on GA-comprehensive calculation method, the yield distribution of gasification components and conversion rate of fixed carbon in gasification process are calculated by GA-comprehensive calculation method, enhancing the computing reliability through the combination of theoretical calculation and process simulation. The simulation values of gasification gas compositions have good agreement with experimental values, which reveals pyrolysis stage and gasification process clearly. Generally, the proposed innovative model contributes to the prediction of component distribution of biomass pyrolysis and gasification, along with parameters optimization of gasification system.

Dispersing the metal oxide active component on the porous carrier by impregnation and loading is a common method for preparing highly active metal oxide desulfurizers. However, due to the decrease of porosity of the carrier due to the loading of active components, the desulfurization capacity of active components cannot be fully utilized. In this study, cheap low-rank coal was directly used as raw material. After pretreatment, zinc nitrate was added into the coal to prepare ZnO based activated carbon desulfurizer at room temperature in one step through physical-chemical activation method. The preparation of activated carbon and the loading of active components were completed in one step. The effects of zinc nitrate immersion amount, activation temperature and activation time on desulfurization performance of desulfurizer were studied. The results showed that when the immersion amount was 20%(mass), the activation temperature was 850℃, and the activation time was 1 h, the breakthrough time of desulfurizer was 210 min, and its sulfur capacity was 71.4 mg/g. Its desulfurization performance was 5.3 times that of commercial activated carbon supported ZnO desulfurizer under the same experimental conditions. The high desulfurization performance is mainly attributed to its developed mesoporous pores, which is not only conducive to mass transfer, but also beneficial to the storage of sulfide products.

Catering wastewater is a kind of high-concentration organic wastewater with severe pollution and complex components. In order to reduce the load of biochemical treatment, this study uses coagulation sedimentation process to pretreat catering wastewater, and uses response surface methodology to optimize the coagulation process conditions. Scanning electron microscopy (SEM), X-ray energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) were used to analyze the changes of composition and structure of flocs. Three-dimensional fluorescence spectrum were used to compare the changes of organic matter before and after catering wastewater treatment, and the degradation mechanism of catering wastewater was explored. The results showed that when the initial pH was 7.75, FeCl₃ dosage was 101.84 mg/L, stirring time was 42.05 s and sedimentation time was 25.99 min, removal efficiency of COD predicted was 45.34% by using the response surface method. The deviation was only 0.02%(<2%) compared with the measured value. According to SEM, EDS and XRD analysis, the surface of suspended solids in the raw water before coagulation was relatively flat. The surface of the precipitate particles after coagulation was rough, and the surface of floc had obvious spatial network structure. The flocs mainly contained C, Cl, Na, O, N, P and other elements before and after the coagulation and the surface of flocs adhered to iron hydroxide after the coagulation. The analysis of three-dimensional fluorescence showed that the coagulation sedimentation process could effectively remove soluble microbial by-products and humic acids.

Due to its controllable structure and unique physical and chemical properties of the channel, the two-dimensional membrane has shown great application potential in many separation fields such as gas separation, seawater desalination, and sewage treatment. In this paper, the PVA/LDH composite membrane is constructed by layers stacking, in which layered Mg/Al hydroxide (LDH) monolayer and polyvinyl alcohol (PVA) polymer chain form hydrogen bond interaction. The effects of the ratio of PVA to LDH on the lamellar structure and the height of the lamellar spacing of the composite membranes are investigated by SEM and XRD. The water flux and dyes rejection of PVA/LDH composite membranes are investigated. The results show that the cross-sections of the composite membranes with different PVA mass fractions have lamellar structures. Compared with the LDH membrane, the interlayer spacing of the composite membranes is decreased due to the hydrogen bonding interaction. With the increase of PVA content, the interlayer spacing of the composite membranes decreased firstly and then increased, in which the content of PVA is 15%, the value of spacing is minimum, while the content of PVA exceeds 15%, the interlayer spacing increased. The pure water flux of the composite membrane with a PVA mass fraction of 25% is the largest. The composite membrane has excellent rejection performance for the molecular weight of dye molecules in the range of 300—800, and the rejection rate is more than 97%. This work provides a novel path for the treatment of printing and dyeing wastewater.

China is rich in coal resources. Using coal as a raw material to prepare carbon nanotubes can achieve efficient utilization of coal resources, reduce environmental pollution, and provide a new way for the development of the coal industry.Three N-doped carbon micro-nanotubes with high graphitization degree were successfully synthesized by an approach coupling catalytic pyrolysis with chemical vapor deposition, using home-made coal-based polyaniline as a carbon and nitrogen source, selecting nickel acetate or ferric citrate as a pyrolysis catalyst and choosing nickelocene, nickel acetate or ferrocene as a catalyst for the growth of carbon tubes. The results of SEM, TEM, XRD, Raman and XPS tests showed that three carbon micro-nanotubes exhibited various morphologies including erect tubes, curved tubes and bamboo-like tubes. Nickelocene and ferrocene catalyst were suitable for growing long and upright tubes, and nickel acetate catalyst was beneficial for growing short and curved tubes. The yield of carbon micro-nanotubes grown by nickelocene catalyst was closed to that of nickel acetate catalyst and they were approx 5.8%(mass). In contrast, the yield of carbon micro-nanotubes grown by ferrocene catalyst was higher to 21.2%(mass). Furthermore, the as-doped N element mostly existed in three carbon micro-nanotubes with the chemical state of graphitic N. The carbon micro-nanotubes grown by nickel acetate catalyst had the highest N-doping content, up to 1.17%(mass), which was a suitable support for MOR electrocatalysts.

A small-scale flammable gas explosion venting test system was built by using a 2 L acrylic glass container. Based on the small-scale experiments, the explosion venting process of petroleum fuel vapor-air premixed gas under different explosion relief areas was studied. The dynamic characteristics of overpressure in the internal and external fields with time under the condition of typical opening ratio were obtained. The effects of opening ratio on overpressure and flame parameters were analyzed, and the explosion releasing modes are classified. The results show that: (1) Under the conditions of different venting coefficients, the venting modes of petroleum fuel vapor-air premixed gas include closed combustion induced by venting failure, jet combustion induced by venting success and external explosion induced by venting success. The overpressure-time dynamic curve, overpressure peak value, flame propagation velocity and flame propagation distance of three venting modes are analyzed. The results show that there are significant differences between the small-scale experiment and the medium-scale experiment. There are membrane breaking overpressure peak(Δp₁), flame jet overpressure peak(Δp₂), and external explosion overpressure peak(Δp₃); (2) When K_v≤39.68, the maximum overpressure peak in the internal field, the maximum axial overpressure peak in the external field, the maximum flame propagationvelocity, and the axial flame propagation distance all increase with the increase of K_v, and the radial flame propagation distance decreases with the increase of K_v; (3) When K_v≤4.41, the peak values of axial and radial maximum overpressure are caused by external explosion (Δp_3(ver) and Δp_3(hor)); when 7.94≤K_v≤39.68, the peak values of axial and radial maximum overpressure are caused by impingement of flame jet and rupture of explosion relief plate respectively (Δp_2(ver) and Δp_1(hor)); (4) The critical K_v of successful venting and failed venting is between 39.68 and 158.74, and the critical K_v of external explosion and jet combustion is between 4.41 and 7.94.