离子液体工艺的系统集成研究
文献类型：学位论文
| 作者 | 田肖 |
| 学位类别 | 博士 |
| 答辩日期 | 2011-05-24 |
| 授予单位 | 中国科学院研究生院 |
| 导师 | 张锁江 ; 张香平 |
| 关键词 | 离子液体 多层次模拟 多目标优化 绿色度 流程模拟 |
| 其他题名 | System integration of processes using ionic liquids |
| 学位专业 | 化学工程 |
| 中文摘要 | 以离子液体为介质的工艺是一个涉及多个尺度、多种因素的复杂过程，需要从系统工程的角度进行集成优化，以保证全局的资源、能源、经济和环境的协调最优。本文基于量化计算、COSMO-RS模型、热力学模型和流程模拟等多种模拟计算工具，结合绿色度理论和多目标优化算法，对离子液体抽提分离丁二烯、吸收捕集CO2、催化联产碳酸二甲酯/乙二醇等三个工艺进行了系统集成研究。本文的主要创新性成果如下： (1) 基于量子化学计算和COSMO-RS模型计算，考察了丁二烯抽提溶剂的萃取性能与其结构之间的关系，得到离子液体筛选原则：极性大、体积小、氢键键合能力强；考察了阳离子对分离性能的影响，发现随着烷基侧链碳数的增大，离子液体的分离能力先减小后增大，同时烷基侧链的功能化会使萃取性能变差；根据电子密度分析，发现阴离子对分离性能具有更重要的影响；基于流程模拟、神经网络、遗传算法以及绿色度理论，对离子液体工艺进行了考虑环境影响的多目标优化，发现离子液体新工艺与原乙腈工艺相比，能耗可降低27.2%，绿色度提高9.25%，丁二烯回收率提高0.71%，乙腈用量减少24%。 (2) 基于量子化学计算和COSMO-RS模型计算，发现由于内部存在氢键结构，常规离子液体具有比有机溶剂更好的吸收CO2性能；得到了筛选离子液体吸收剂的准则：阳离子具有长碳链、C-2位上无取代，阴离子具有大的偶极、四极和体积；考察了水对离子液体吸收吸能的影响，发现水通过与离子液体发生氢键作用，可使其性能降低；考察了功能化离子液体[MDEA][Cl]的吸收机理，发现其吸收性能由其化学活性和氢键成键能力共同决定；基于COSMO-RS模型，建立了[MDEA][Cl]吸收体系的热力学模型；基于流程模拟，发现与原MDEA工艺相比，离子液体工艺可使总能耗降低26.2%，溶剂损失降低61.6%，吸收富液中CO2的载量增加98.2%，二氧化碳收率提高0.1%。 (3) 基于流程模拟、神经网络和遗传算法，对离子液体催化联产碳酸二甲酯/乙二醇工艺进行了集成优化，发现相对于Texaco工艺，离子液体新工艺可使每吨EG产品的净收益提高593元，相对原工艺增加11.5%，同时工艺能耗降低8.7%。 |
| 英文摘要 | Industrial applications of ionic liquids (ILs) are nonlinear and complex processes involving multi-scale problems and cross-coupled factors. Efforts on the system integration and optimization of these processes are essential to maintain the critical balance among energy, economy and environment. In this work, the system integration is accomplished for three typical processes using ILs: IL extracting 1,3-butadiene from C4 fractions, IL absorbing carbon dioxide and coproduction of dimethyl carbonate (DMC) and ethylene glycol (EG) catalyzed by ILs, based on chemical quantum calculation, COSMO-RS, thermodynamic models and process simulation. Besides, the multi-objective optimization considering the environmental impact is carried out for each of the processes, respectively. The innovative results of the dissertation are as follows. (1) Based on chemical quantum calculation and COSMO-RS model, the relationship between the extraction performance of ILs and their structures was investigated, a principle of screening ILs was obtained: the one with large polarity, small molecular volume and strong hydrogen-bonding ability will performs better; the influence of the cation of on ILs’ extraction behavior was also studied, and it was found that their separation ability increases firstly and then decrease with the carbon number of the alkyl side chain on imidazolium cation, and the ability will be weaken by functioning the alkyl side chain. By analyzing the electron density of ILs, it was found that anions have impose more effects on ILs’ performance than cations. Besides, binary interaction parameters in UNIFAC model were regressed for the IL mixture. Finally, the IL process was integrated and optimized based on process simulation and multi-objective algorithm, and it was found that the process compared with acetonitrile (ACN) process has a lower energy consumption by 27.2%, a greater GD by 9.25%, a higher production yield by 0.71% and a less ACN consumption by 24%. (2) Based on chemical quantum calculation and COSMO-RS model, the mechanism of conventional ILs absrobing CO2 was investigated. It was found that the existing hydrogen bond network in the bulk of ILs makes them have a superior performance to traditional organic sovlent such as sulfolane. A principle of screening conventional IL absorbent was obtained: its cation should have a larger alkyl side chain and no substituent group at C-2 site, and its anoin should have larger dipole, quadrupole and molecular volume. For the task specific IL [MDEA][Cl], ab initio calculation indicates that the performance of IL absorbing CO2 was determined by both of its chemical activity and H-bonding ability. Besides, binary interaction parameters in NRTL model for the [MDEA][Cl] absorbing system was regressed based on COSMO-RS calculation. Based on process simulation, it was found that the integrated [MDEA][Cl] process compared with MDEA process has a lower energy consumption by 26.2%, a less solvent loss by 62.6% and a larger CO2 load amount in rich solvent by 98.2% and a higher product yield by 0.1%. Based on process simulation, the coproduction process of DMC and EG catalyzed by ILs was integrated and optimized. It was found that the optimized IL process compared with Texaco process could increase the net profit per ton of EG by 11.5%, i.e., 593 RMB, and lower energy consumption by 8.7%. The results provide a theoretic guideline for the design of a real-life IL process. |
| 语种 | 中文 |
| 公开日期 | 2013-09-24 |
| 页码 | 173 |
| 源URL | [http://ir.ipe.ac.cn/handle/122111/1731]  |
| 专题 | 过程工程研究所_研究所（批量导入） |
| 推荐引用方式 GB/T 7714 | 田肖. 离子液体工艺的系统集成研究[D]. 中国科学院研究生院. 2011. |
入库方式： OAI收割
来源：过程工程研究所
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