The effects of pressure ( p ), superficial gas velocity ( U _G) and solid concentration ( c _v) on gas bubble size, gas holdup( ε _G)and gas liquid interfacial area ( a ) in a large scale slurry bubble column reactor were investigated. The gas-liquid-solid three phases were methane, mixture of decanes and glass beads with 15-20 μm diameter respectively in this study. The experiments were selected on the basis of three main process variables ( p,U _G and c _v) at five levels and a statistical correlation ε _G to the three main process variables was proposed from the data obtained. Further, the relationship between gas holdup and gas momentum per unit mass slurry was determined and could be expressed as ε _G=3 M ^1/3 _Gexp(-1.5 c _v). Gas holdup values were measured by using the manometric method and were found to increase with pressure and superficial gas velocity due to the increase of the number of the small and large gas bubbles, respectively, it decreased with increasing solid concentration due to the decrease of the number of the small gas bubbles. Consequently,the interfacial area was found to increase with superficial gas velocity and pressure, and decrease with solid concentration.

In this paper,the adsorption of alkane-alcohol binary non-aqueous solutions on DOO1 and TS-TR resins is investigated.Local adsorption isotherms (20?℃) from binary liquid mixture consisting of butanol-heptane,ethanol-hexane on two kinds of resins with a fixed moisture content are measured respectively.Based on NBP-a model,an isotherm adsorption model was developed,and energy distribution density function is developed with Stieltjes transform.Results show that surface energy heterogeneity of adsorbent and nonideality of solution play an important role in the adsorption.Moisture content in resin also affects on its surface energy heterogeneity.The surfac energy heterogeneity of polar DOO1 resin increased with moisture content,and the surface energy heterogeneity of non-polar TS-TR resin also changes significantly with moisture content.Calculated results with the adsorption model agree with the results of experiments.

A parallel flow model of isothermal one-dimension pseudo-homogeneous membrane reactor for methanol synthesis from CO ₂ in silicone rubber/ceramic composite membrane reactor was developed. Runge-Kutta method was adopted to simulate the process behavior in the membrane reactor. Such parameters which affect the reaction behavior in the membrane reactor,as operation parameter, Damkhler number Da , pressure ratio p _r, reaction temperature T , membrane separation α , membrane permeation parameter Φ , mole ratio γ of H ₂ to CO ₂, flux ratio q ₁ of purge gas to feed as well as L ₁ the nonuniform parameter of membrane permeation, were discussed in detail.

The reaction kinetics of n -butane selective oxidation to maleic anhydride over a domestic VPO catalyst was experimentally studied under a wide range of operation conditions.Space velocity was larger than 3000h ^-1 ,reaction temperatures were 350-446℃,feed concentrations of n -butane and oxygen were 0.5%- 3.2% and 5.5% - 26.5% respectively.A triangular reaction network was adopted to describe this complex reaction system.A set of intrinsic rate equations were identified by fitting the model of the laboratory reactor with experimental data and model parameters were estimated.Statistical test confirmed the study.

The UV-vis/H ₂O ₂/Ferrioxalate process is an advanced oxidation process.The hydroxyl radical (·OH) generating in this process is a strong oxidant and reacts rapidly with organic compounds in water.Here aniline wastewater was treated by this oxidant.The oxidation behavior and effect was studied.The optimum conditions to remove aniline from wastewater by UV-vis/H ₂O ₂/Ferrioxalate process were as follows:pH= 3.5 ,Fe ²⁺ ∶H ₂O ₂∶C ₂O ₄ ^2- ≈1∶4∶6 (mole).The UV-vis/H ₂O ₂/Ferrioxalate process was very efficient for the treatment of water highly contaminated by aniline and the removal efficiency of aniline was more than 99% within 12min.The disposal of simulated aniline water sample by dynamic process was better than by static process.

Low concentration of phenol (100-800mg·L ^-1 ) as a model contaminant for wastewater treatment by electrocatalytic degradation on a fluorine resin modified β -PbO ₂ anode has been investigated.Various influence factors such as initial phenol concentration,applied voltage,initial pH and salinity of the electrolyte were examined.It was observed that the COD of the wastewater decreased by 60mg·L ^-1 and volatile phenols vanished completely in 25min under operational temperature 25℃,applied voltage 7.0V,K ₂SO ₄ 1.0g·L ^-1 ,pH 2.0,and initial phenol concentration 100mg·L ^-1 .The method showed promising applicability for treating phenolic wastewater in high acidity and in high salinity without pretreatment such as dilution or neutralization.The main intermediates of phenol degradation were benzoquinone and organic acids such as oxalic acid and maleic acid and the final product was carbon dioxide,therefore the technique could be used as a waste minimization process for recycling the treated water.Pseudo-first order reaction model can be used for the fitness of COD removal.

A new kind of copolymer is synthesized by condensation polymerization of solica sol and organic silicone monomers.Compared with traditional heat-resisting coatings such as pure organic silicone resin and organic silicone improved by epoxy resin,the new copolymer has not only excellent hardness,but also lower requirement for solidification and improved performance of heat-resistance.

Many papers have described the optimization of cultural conditions for the simultaneous production of glucose oxidase and catalase by fungi.However,to our knowledge, no investigations have been carried out on the kinetic models.Mathematical models of simultaneous production of glucose oxidase and catalase by Aspergillus niger in Erlenmeyer flask were investigated.The kinetic models of cell growth, enzyme production and substrate consumption were proposed.Logistic model for growth,the Luedeking-Piret equation for enzyme production and the Luedeking-Piret-like equation for glucose consumption were in good agreement with the experimental results.The kinetic models appeared to provide a reasonable description for each parameter in the fermentation.The production of both enzymes is growth-associated.

Genetic algorithm was used to estimate the kinetics parameters for the synthesis of ethyl tert -butyl ether from ethanol and tert -butyl alcohol on strong acid cation exchange resin S-54.The standard genetic algorithm was modified by using multiple crossover and mutation strategies instead of simple strategy.The modified genetic algorithm avoided the problem of local optimum and showed higher estimation precision and better convergence than the traditional algorithm of Runge-Kutta.The influences of genetic strategy and the genetic code representation on algorithm performance were also discussed.The calculation results using these parameters obtained with the modified genetic algorithm agreed well with experimental data.

Pinch analysis is now the main method to synthesize mass exchanger networks,usually minimum external lean stream flow-rate as objective.The capital cost could not be considered in the network analysis or it is difficult to take capital cost into consideration.With the deficiency of pinch analysis in mind,this paper presents a method for synthesizing the mass exchanger networks considering not only operating cost but also capital cost by using Genetic-Alopex mixing algorithms.According to the peculiarity of Genetic-Alopex algorithms and mass exchanger networks,a mathematical model for mass exchanger networks synthesis is developed.The model uses the total annual cost as objective.A simplified capital cost law is used for determining the number of stages required,which is then converted to a capital cost.The solving process for mass exchanger network synthesis by using Genetic-Alopex algorithms is introduced.This method is applied to a coke-oven gas-sweetening examples to contrast with the pinch technology.The examples computed by Genetic-Alopex algorithm show that the total annual cost is lower though the operating cost is sometimes higher.

Water pollution and scarcity of water is a life-and-death problem the human being is facing.It is worthy of investigation of evolving water-using processes to reduce both fresh water consumption and wastewater production.This paper approaches the optimized design of water-using processes,i.e. wastewater minimization.The concepts of process source and process sequence are introduced.For reuse process of a single contaminant and multiple contaminants along with regeneration and reuse process of a single contaminant,a new computation method is addressed respectively,which is named as step by step linear programming method.From the beginning,the processes are sectionalized or collated according to the limiting operating data of lean streams, and then the matching between rich streams and lean streams(water sources) is optimized step by step in accordance with the collated processes, ultimately the design of water-using network is attained.Four examples are solved to demonstrate the effectiveness and convenience of the new method.

This paper addresses the problem of optimal design of batch processes with uncertain processing times.A method is proposed for defining the limiting cycle times under uncertain processing times.The limiting cycle times represented in the model become independent of each other.Thus,the process can be transferred into a renewal process and a stochastic optimization formulation is developed based on renewal process theory.An example shows that the optimal design considering the uncertainty of processing times can give better results than that without considering the uncertainty.The method is shown to be effective by simulation experiments.

This paper addresses the problem the design of batch processes under uncertain processing times with waiting time limit.A new method for production scheduling is proposed.Compared with schedule on line, this method can simplify production scheduling, and is suitable for long-term production.The proposed method can simplify the design of batch processes.The simulation experiments show the suitability of the method.

The ion-exchange equilibrium of bovine serum albumin (BSA) on an anion exchanger was studied.The usefulness of steric mass-action (SMA) model was analyzed for describing protein ion-exchange equilibrium in different buffer systems.The results showed that the SMA model was useful in the prediction of protein adsorption decrease with increasing ionic strength in a wide pH range.However,at higher salt concentrations where very low protein adsorption was achieved,the model predicted adsorption capacity was higher than the experimental results.At lower pH close to the isoelectric point of BSA,the accuracy of the model prediction further decreased.It is considered that the SMA model could be further improved by taking into account the factors influencing the three-dimensional structure of proteins (e.g., pH) and the effect of salt concentration on the intermolecular interactions of proteins.

The combustion reactivity of chars from pyrolysis of Shenmu coal maceral concentrates under different pyrolysis temperature, heating rate and pressure were systematically investigated by using TGA.The results indicated that the combustion reactivity of chars was related to pyrolysis temperature, pressure,heating rate and distribution of elements in chars.With decreasing temperature and pressure and increasing heating rate,the combustion reactivity of the pyrolysis residues increased.The lower carbon content and higher hydrogen content in chars,the higher combustion reactivity of chars.Under the same pyrolysis condition,the vitrinite chars had higher combustion reactivity than the fusinite chars.

Polyethylene glycol diacrylates(PEGDA)monomers, which contain double bond on the terminal group of polyethylene glycol(PEG)and can be used in synthesis of UV-curable solid polymer electrolytes (SPE), were prepared through esterification of PEG and acrylic acid.A cured conductive polymer film consisting of lithium salt was then obtained by irradiation with ultraviolet rays.The factors affecting film-forming,photosensitivity and conductance were studied.From experiments, while Li/O=1/6 and n =18,the ionic conductivity of the SPE membrane could reach 10 ^-5 S·cm ^-1 at room temperature and its performance was relatively good.

Air was fed into a packed extraction column to increase turbulence,enhance liquid droplet dispersion and surface renewal,and thus raise mass transfer area.This led to improvement of liquid-liquid contact and mass transfer.The experiments on hydrodynamics and mass transfer were carried out with air-kerosene (benzoic acid)-water system, and the effect of air agitation was investigated.It is clear from the results that the air hold-up ,dispersed phases hold-up and mass transfer coefficient increase and flooding velocity goes down while increasing superficial air velocity.The over-agitation of air can cause over-dispersion and emulsification of the dispersed phase,deterioration of mass transfer performance,and even flooding.Packing helps to break up the droplet of dispersed phase and can effectively prevent the liquid from longitudinal mixing in extraction column,so the mass transfer performance of packed column is far better than that of non-packed.

One-step synthesis of DME (dimethyl ether) from syngas on hybrid catalyst is studied.In the experiment,the effects of variables including composition of feed gas,temperature and pressure are studied under the condition as follows:the catalyst was composed of C302 methanol synthesis catalyst and CM-3-1 methanol dehydration catalyst (mixing ratio 1∶1).Liquid paraffin is used as inert solvent.The reaction temperature is in the range of 230-270℃ and the pressure is in the range of 3.0-5.0MPa.It turns out that with the temperature and pressure increasing the conversion of carbon,the selectivity and production rate of dimethyl ether increase,while the selectivity and production rate of methanol decrease.Furthermore,both the conversion of carbon and the selectivity of dimethyl ether are high for the syngas of appropriate CO ₂.