丙烯/丙烷分离的离子液体设计与工艺并行优化

doi:10.11949/0438-1157.20251221

摘要/Abstract

摘要：

丙烯/丙烷作为近沸难分离物系，现有精馏技术存在高能耗和高设备投资等问题。离子液体可忽略的挥发特性及强作用力属性，使得其在分离近沸物系方面得到了广泛研究。因此，本研究通过多尺度模拟，分析了离子液体强化丙烯/丙烷的微观机制及工艺性能。研究提出了一种基于MATLAB平台的计算机辅助离子液体设计与工艺并行优化的集成策略，采用基团贡献法和生成测试的求解策略进行离子液体设计。基于多粒子并行的粒子群优化方法对多种进料工况和多种离子液体工艺进行并行优化。结果表明，［MMIM］［TFA］强化丙烯/丙烷分离的机理是离子液体与丙烯间的π-π、C-H···π和π···H···O相互作用，离子液体与丙烯的静电作用力强于与丙烷的静电作用力，从而显著提高了丙烯/丙烷的选择性。与热泵精馏及ACN水溶液萃取精馏相比，［MMIM］［TFA］萃取精馏节能工艺的年总成本分别降低了38.26%~45.45%和24.04%~40.07%。

关键词: 丙烯/丙烷, 离子液体, 萃取精馏, 分离机制, 粒子群优化

Abstract:

As a close-boiling and difficult-to-separate system, the separation of propylene/propane via conventional distillation faces challenges such as high energy consumption and significant equipment investment. Ionic liquids have garnered extensive research interest for separating close-boiling mixtures due to their negligible volatility and strong interaction abilities. Therefore, this study employs multi-scale simulations to investigate the microscopic mechanism and process performance of ionic liquids in enhancing propylene/propane separation. An integrated strategy combining computer-aided ionic liquid design and process parallel optimization is proposed based on the MATLAB platform. The ionic liquid design is achieved using a group contribution method combined with a generate-and-test strategy, while a multi-particle parallel swarm optimization method is used to perform parallel optimization for multiple ionic liquids and feedstocks. Results indicate that the mechanism of [MMIM][TFA] in enhancing propylene/propane separation involves π-π, C-H···π, and π···H···O interactions between the [MMIM][TFA] and propylene. The interaction between the [MMIM][TFA] and propylene is stronger than that with propane, significantly improving the selectivity of propylene/propane. Compared with the processes of heat pump distillation and ACN-water extractive distillation, the annual total cost of the energy-efficient [MMIM][TFA]-based extractive distillation process is reduced by 38.26% to 45.45%, and 24.04% to 40.07%, respectively.

Key words: propylene/propane, ionic liquid, extractive distillation, separation mechanism, particle swarm optimization

中图分类号:

TQ 021.8

罗凯, 郭超, 侯微, 贺革. 丙烯/丙烷分离的离子液体设计与工艺并行优化[J]. 化工学报, DOI: 10.11949/0438-1157.20251221.

Kai LUO, Chao GUO, Wei HOU, Ge HE. Design of ionic liquids and process parallel optimization for separation of propylene/propane[J]. CIESC Journal, DOI: 10.11949/0438-1157.20251221.

图/表 10

图1 计算机辅助离子液体设计方法

Fig.1 Computer-aided ionic liquid design method

图2 基于PSO算法的工艺并行优化方法

Fig. 2 The process parallel optimization methods using PSO algorithm

表1 离子液体设计结果及热力学和物性数据

Table 1 Design results of ionic liquids and their thermodynamic properties

排名	离子液体	MW(g/mol)	S	T_m (K)	η(cp)
1	1CH₃, 1[MIM][TFA]	210.2	3.1	271.7	16.6
2	1CH₃, 1CH₂, 1[MIM][TFA]	224.2	3.0	267.9	19.1
3	1CH₃, 3CH₂, 1[MIM][TFA]	252.2	2.8	264.2	21.9
4	1CH₃, 1[MIM][SCN]	155.2	2.5	304.8	14.8
5	1CH₃, 3CH₂, 1[MIM][TfO]	288.3	2.4	322.4	34.8
6	1CH3, 1CH2, 1[MIM][SCN]	169.2	2.1	301.0	17.0

图3 12种混合体系的IGMH可视化及作用力占比分析

Fig.3 IGMH visualization and analysis of the proportion of interactions for 12 complexes

图4 [MMIM][TFA]萃取精馏工艺(a)和节能工艺(b)流程图

Fig.4 Flowsheet of the [MMIM][TFA] extractive distillation process (a) and energy-saving process (b)

图5 不同丙烯进料的[MMIM][TFA]、[EMIM][TFA]、[BMIM][TFA]和ACN水溶液萃取精馏工艺的动态收敛特性

Fig.5 Dynamic convergence characteristics of the [MMIM][TFA], [EMIM][TFA], [BMIM][TFA] and ACN-water-based extractive distillation process at different propylene feedstock

表2 离子液体萃取精馏工艺参数优化结果

Table 2 Optimization results of ionic liquids extractive distillation process parameters

变量	单位	1	2	3	4	5	6	7	8	9	10	11	12
N_T	-	54	65	56	56	52	58	60	57	61	60	48	52
N_E	-	3	4	3	3	3	3	4	3	3	4	3	4
N_F	-	13	19	18	22	17	17	19	23	17	18	16	21
S	kmol/h	394.04	432.12	476.93	478.73	427.93	434.36	446.12	453.57	386.01	376.58	457.18	410.56
D	kg/h	7677.6	5885.73	3788.39	1194.12	7678.27	5884.01	3786.01	1194.31	7677.95	5886.28	3787.47	1193.81
RR	-	4.8	6.27	9.59	27.99	4.86	4.66	11	33.28	5.05	6.37	10.27	29.74
T	℃	64.4	64.32	66.46	69.78	74.6	78.32	74.33	74.5	102.15	103.33	101.45	103.18
P	MPa	0.619	0.661	0.539	0.476	0.532	0.466	0.526	0.535	0.495	0.337	0.394	0.297
X	-	0.9816	0.9799	0.9860	0.9894	0.9748	0.9815	0.9748	0.9745	0.9718	0.9818	0.9782	0.9841

表3 ACN水溶液萃取精馏工艺参数优化结果

Table 3 Optimization results of ACN-water-based extractive distillation process parameters

变量	单位	13	14	15	16
N_T	-	97	96	87	76
N_E	-	5	4	4	5
N_F	-	40	37	32	31
S	kmol/h	1742.55	1721.84	1857.96	2030.24
D	kg/h	7664.23	5880.04	3783.23	1187.13
RR	-	7.07	9.45	13.09	30.44
N_T1	-	23	22	22	22
N_F1	-	8	9	9	9
D₁	kg/h	17030.01	18776.05	20832.12	23375.33
RR₁	-	0.79	0.64	0.59	0.56

图6 不同丙烯进料的[MMIM][TFA]、[EMIM][TFA]和[BMIM][TFA]工艺的离子液体纯度对TAC的影响: (a) 70wt%; (b) 76.9wt%; (c) 85wt%; (d) 95wt%注:↔—[MMIM][TFA];●—[EMIM][TFA];⯅—[BMIM][TFA]

Fig.6 Effect of ionic liquid purity on TAC for [MMIM][TFA], [EMIM][TFA], and [BMIM][TFA] processes at different propylene feedstock: (a) 70wt%; (b) 76.9wt%; (c) 85wt%; (d) 95wt%

图7 不同丙烯进料下[MMIM][TFA]萃取精馏节能工艺和[MMIM][TFA]、[EMIM][TFA]、[BMIM][TFA]、ACN水溶液萃取精馏和HPD工艺的TUC (a)、TEC (b)、TAC (c)和气体排放(d)的比较

Fig.7 Comparisons of TUC (a), TEC (b), TAC (a) and gas emissions (b) for [MMIM][TFA] extractive distillation energy-saving process, [MMIM][TFA], [EMIM][TFA], [BMIM][TFA], ACN-water-based extractive distillation and HPD processes at different propylene feedstock.

参考文献 36

[1]	王子宗, 刘罡, 王振维. 乙烯丙烯生产过程强化技术进展及思考[J]. 化工进展, 2023, 42(4): 1669-1676.
	Wang Z Z, Liu G, Wang Z W. Progress and reflection on process intensification technology for ethylene/propylene production[J]. Chemical Industry and Engineering Progress, 2023, 42(4): 1669-1676.
[2]	李文学, 韩东, 杨卫兰. 中国丙烯及下游产品发展回顾及展望[J]. 现代化工, 2024, 44(5): 11-14.
	Li W X, Han D, Yang W L. Review and outlook on development of China's propylene and its downstream products[J]. Modern Chemical Industry, 2024, 44(5): 11-14.
[3]	Chen S, Chang X, Sun G D, et al. Propane dehydrogenation: catalyst development, new chemistry, and emerging technologies[J]. Chemical Society Reviews, 2021, 50(5): 3315-3354.
[4]	谢磊, 安赵成, 崔莉程, 等. 气体分馏装置丙烯精馏塔的模拟与优化[J]. 炼油与化工, 2022, 33(2): 61-64.
	Xie L, An Z C, Cui L C, et al. Simulation and optimization of propylene rectification tower in gas fractionation unit[J]. Refining and Chemical Industry, 2022, 33(2): 61-64.
[5]	叶启亮, 徐超洋, 王丽涛, 等. 隔壁精馏塔分离氯丙烯工艺模拟优化[J]. 化学工程, 2024, 52(10): 52-57.
	Ye Q L, Xu C Y, Wang L T, et al. Simulation and optimization of separation of 3-chloropropene in dividing wall column[J]. Chemical Engineering (China), 2024, 52(10): 52-57.
[6]	Woo H C, Kim Y H. Solvent selection for extractive distillation using molecular simulation[J]. AIChE Journal, 2019, 65(9): e16665.
[7]	Gui Y H, Guo C, Liang J C, et al. Thermo-kinetic synergy in separating dimethyl carbonate/methanol/water mixtures using ionic liquids-based mixed solvents[J]. Separation and Purification Technology, 2025, 356: 129849.
[8]	Guo C, Zheng Y, Wang S, et al. Energy-efficient heat pump-assisted pre-concentration integrated with sequential [EMIM][BF₄] and ethylene glycol-based extractive distillation for enhanced recovery of ethanol and isopropyl alcohol from wastewater[J]. Separation and Purification Technology, 2025, 357: 130073.
[9]	Yu B Y, Chien I L. Design and optimization of the methanol-to-olefin process. part II: comparison of different methods for propylene/propane separation[J]. Chemical Engineering & Technology, 2016, 39(12): 2304-2311.
[10]	Cruz Valdez J A, Avilés Martínez A, Vallejo Montesinos J, et al. Maximizing propylene separation from propane by extractive distillation with aqueous N-methyl-2-pyrrolidone as separating agent[J]. Chemical Engineering & Technology, 2021, 44(9): 1726-1736.
[11]	王键吉, 张锁江, 韩布兴. 前言: 离子液体前沿专刊[J]. 中国科学: 化学, 2021, 51(10): 1311-1312.
	Wang J J, Zhang S J, Han B X. Preface: special issue on the frontiers of ionic liquids[J]. Scientia Sinica Chimica, 2021, 51(10): 1311-1312.
[12]	Palomar J, Lemus J, Navarro P, et al. Process simulation and optimization on ionic liquids[J]. Chemical Reviews, 2024, 124(4): 1649-1737.
[13]	容凡丁, 丁泽相, 曹义风, 等. 离子液体强化不饱和键差异化合物分离的研究进展[J]. 化工进展, 2024, 43(1): 198-214.
	Rong F D, Ding Z X, Cao Y F, et al. Progress in enhanced separation of compounds differing in unsaturated bonds by ionic liquids[J]. Chemical Industry and Engineering Progress, 2024, 43(1): 198-214.
[14]	Lei Y, Yu Z Y, Wei Z Q, et al. Energy-efficient separation of propylene/propane by introducing a tailor-made ionic liquid solvent[J]. Fuel, 2022, 326: 124930.
[15]	Kim H, Lee B, Lim D, et al. What is the best green propylene production pathway?: technical, economic, and environmental assessment[J]. Green Chemistry, 2021, 23(19): 7635-7645.
[16]	国家市场监督管理总局, 中国国家标准化管理委员会. 聚合级丙烯: [S]. 北京: 中国标准出版社, 2024.
	State Administration for Market Regulation, Standardization Administration of the People's Republic of China. Propylene for polymerization: [S]. Beijing: Standards Press of China, 2024.
[17]	Lei Z G, Zhang J G, Li Q S, et al. UNIFAC model for ionic liquids[J]. Industrial & Engineering Chemistry Research, 2009, 48(5): 2697-2704.
[18]	Lei Z G, Dai C N, Liu X, et al. Extension of the UNIFAC model for ionic liquids[J]. Industrial & Engineering Chemistry Research, 2012, 51(37): 12135-12144.
[19]	Dong Y C, Guo Y Y, Zhu R S, et al. UNIFAC model for ionic liquids. 2. revision and extension[J]. Industrial & Engineering Chemistry Research, 2020, 59(21): 10172-10184.
[20]	Zhu R S, Kang H W, Liu Q H, et al. UNIFAC model for ionic liquids: 3. revision and extension[J]. Industrial & Engineering Chemistry Research, 2024, 63(3): 1670-1679.
[21]	Lazzús J A, Pulgar-Villarroel G. A group contribution method to estimate the viscosity of ionic liquids at different temperatures[J]. Journal of Molecular Liquids, 2015, 209: 161-168.
[22]	Lazzús J A. A group contribution method to predict the melting point of ionic liquids[J]. Fluid Phase Equilibria, 2012, 313: 1-6.
[23]	Yang A, Wang W H, Sun S R, et al. Sustainable design and multi-objective optimization of eco-efficient extractive distillation with single and double entrainer(s) for separating the ternary azeotropic mixture tetrahydrofuran/ethanol/methanol[J]. Separation and Purification Technology, 2022, 285: 120413.
[24]	Yang A, Kong Z Y, Sunarso J. Design and optimisation of novel hybrid side-stream reactive-extractive distillation for recovery of isopropyl alcohol and ethyl acetate from wastewater[J]. Chemical Engineering Journal, 2023, 451: 138563.
[25]	Yang A, Zou H C, Chien I L, et al. Optimal design and effective control of triple-column extractive distillation for separating ethyl acetate/ethanol/water with multiazeotrope[J]. Industrial & Engineering Chemistry Research, 2019, 58(17): 7265-7283.
[26]	Heris M K. Multi-Objective PSO in MATLAB[EB/OL]. 2015. .
[27]	Frisch M J, Trucks G W, Schlegel H B. Gaussian 16, RevisionC. 01, Gaussian[EB/OL]. 2019. .
[28]	Lu T. Molclus Program, 1.8.5Version. Beijing Kein Research Center for Natural Science[EB/OL]. 2019. .
[29]	Stewart J J P. MOPAC: a semiempirical molecular orbital program[J]. Journal of Computer-Aided Molecular Design, 1990, 4(1): 1-103.
[30]	Chai J D, Head-Gordon M. Long-range corrected hybrid density functionals with damped atom–atom dispersion corrections[J]. Physical Chemistry Chemical Physics, 2008, 10(44): 6615-6620.
[31]	Lu T, Chen Q X. Independent gradient model based on Hirshfeld partition: a new method for visual study of interactions in chemical systems[J]. Journal of Computational Chemistry, 2022, 43(8): 539-555.
[32]	Lu T, Liu Z Y, Chen Q X. Comment on "18 and 12–Member carbon rings (cyclo[n]carbons)–A density functional study"[J]. Materials Science and Engineering: B, 2021, 273:115425.
[33]	Liang J C, Guo C, Liu X Y, et al. Economic and environmental benefits of novel process of ionic liquids-based toluene absorption from exhaust gas at atmospheric pressure[J]. Journal of Cleaner Production, 2024, 470: 143283.
[34]	Guo C, Luo K, Hou W, et al. A novel [MMIM]-based ionic liquid extractive distillation process for achieving liquid-phase propylene at 1.8 MPa with enhanced energy-economic-environmental benefits[J]. Journal of Cleaner Production, 2025, 525: 146579.
[35]	Chen H, Li X G, He L, et al. Energy, exergy, economic, and environmental analysis for methyl acetate hydrolysis process with heat integrated technology used[J]. Energy Conversion and Management, 2020, 216:112919.
[36]	Luo K, Guo C, Liang J C, et al. Energy and cost-efficient ionic liquids extractive distillation for producing electronic and polymer-grade propylene with emphasis on feedstock variability[J]. Separation and Purification Technology, 2025, 358: 130258.