Isobaric vapor–liquid equilibria for mixtures of tetrahydrofuran, 2-propanol, and 2,2,4-trimethylpentane at 101.3 kPa

Vapor–liquid equilibrium (VLE) at 101.3 kPa have been determined for a ternary system (tetrahydofuran + 2-propanol + 2,2,4-trimethylpentane) and its constituent binary systems (tetrahydrofuran + 2-propanol, tetrahydrofuran + 2,2,4-trimethylpentane, and 2-propanol + 2,2,4-trimethylpentane). The activity coefficients of liquid mixtures were calculated from the modified Raoult's law. Thermodynamic consistency tests were performed for all VLE data. The VLE data of the binary mixtures and ternary mixtures were correlated using the Margules, Wilson, NRTL, and UNIQUAC activity-coefficient models. The models with their best-fitted interaction parameters of the binary systems were used to predict the ternary vapor–liquid equilibrium. All VLE data are also used to calculate the reduced excess molar Gibbs free energy g^E/RT and the deviations in the boiling point ΔT. The calculated quantities of g^E/RT and ΔT were fitted to variable-degree polynomials in terms of liquid composition.     

丙酮-乙酸异丙烯酯二元体系常压汽液平衡

用改进的埃利斯(Ellis)平衡蒸馏器测定了丙酮-乙酸异丙烯酯二元系统在常压下的汽液平衡数据,用液相活度模型Wilson、NRTL方程对测定数据进行关联,采用非线性最小二乘法回归出二元系统在常压下的Wilson、NRTL方程参数,Wilson模型与试验值符合良好.汽液相平衡数据经Herrington面积法检验满足热力学一致性.     

L－K－P状态方程用于多元体系的计算

介绍了Ｌ－ｋ－Ｐ状态方程的对比密度根初值公式，等焓节流过程泡、露点温度的快速迭代公式。当对烃类多元体系进行热力参数、汽－液相平衡等计算时，推荐用两类不同状态方程同时进行计算，以相互校核计算结果。     

溶碱萃取剂对乙醇-水体系汽液平衡的影响

提出了溶碱萃取精馏制取无水乙醇的方法．通过恒沸点相对挥发度的测定与全浓度下的汽液平衡测定，考察了溶碱萃取剂对乙醇一水体系汽液平衡的影响．采用LIQUAC模型与Wilson模型相结合的关联计算方法，进行了汽液平衡数据的预测与萃取精馏工艺条件的模拟．结果表明，与传统的溶盐萃取剂相比，溶碱萃取剂可以更好地提高乙醇-水体系的分离效果．     

乙酸乙酯-乙醇-水-甘油体系中三元及四元体系的汽液平衡数据测定及推算

设计了液液平衡釜，测定乙酸乙酯-乙醇-甘油、乙酸乙酯-水-甘油及乙醇-水-甘油三元体系的VLE数据；以Wilson方程为平衡模型，由两对二元模型和三元体系的VLE实验数据关联第三对模型参数；测定乙酸乙酯-乙醇-水-甘油体系的VLE数据，由二元模型参数及三元体系的VLE实验数据计算乙酸乙酯-乙醇-水-甘油体系的VLE数据并与实验数据比较；本文测定结果及计算结果为乙酸乙酯-乙醇-水、乙酸乙酯-乙醇体系的萃取分离模拟计算及试验提供基础数据。     

Optimal design of catalytic distillation columns: A case study on synthesis of TAEE

The design of catalytic distillation (CD) columns is a challenging task because of the superposition of chemical reaction and distillation in one apparatus. In this work, a method to design a cost-optimal CD column for chemical systems with large number of components and chemical reactions is presented. The method is based on the following steps: (1) estimation of the number of theoretical stages and catalyst volume by the decomposition of the CD column into a sequence of chemical reactors and non-reactive distillation columns, (2) estimation of the column diameter and operating conditions using an equilibrium stage model, and (3) design of the column applying an optimisation algorithm and using a rigorous non-equilibrium stage model to represent the CD process. The method is applied to determine the optimal column configuration and operating conditions for the synthesis of tert-amyl ethyl ether from ethanol and isoamylenes. Eight components and four chemical reactions were selected to represent the chemical system in the simulations.     

Thermodynamics and separation process for quaternary acrylic systems

Vapor‐liquid equilibrium (VLE) and liquid‐liquid equilibrium (LLE) data of binary and ternary acrylic systems were systematically measured. Subsequently, VLLE phase diagrams of binary systems, tridimensional VLE phase diagrams of methyl acrylate (MA)‐methanol (Me)‐H₂O ternary system, and quaternary LLE phase diagrams of MA‐Me‐H₂O‐methyl acetate (MeOAc) system were constructed. These diagrams clearly demonstrated the effects of temperature on phase equilibrium. The experimental data was fitted by the NRTL and UNIQUAC models, and the best‐fitted parameters were used to predict interaction properties of ternary and quaternary mixture. Therefore, the phase equilibrium data were provided as reference for the design of acrylic systems rectification or extraction process. Residue curve was mapped out for MA‐Me‐H₂O system through Aspen plus software. Finally, using thermodynamics and residue curve as theoretical basis, two novel separation processes were proposed and applied to the quaternary acrylic systems. © 2015 American Institute of Chemical Engineers AIChE J, 62: 228–240, 2016     

Co-evaporative multi-component fuel design for in-cylinder PLIF measurement and application in gasoline direct injection research

For in-cylinder fuel mixture distribution measurement, a method for designing a multi-component fuel for planar laser-induced fluorescence (PLIF) experiments is developed based on thermal gravity analysis and vapor–liquid equilibrium calculation. The goal is to create fuel that has a volatility similar to real gasoline and good co-evaporation ratios (near 1.0) with tracers. Acetone, toluene, and trimethylbenzene are chosen as tracers for light, medium, and heavy fractions, respectively, and a five-component test fuel is developed. The test fuel is used to study the influence of components and temperature on co-evaporation ratios. Any variation in tracer or fuel component proportions affects all co-evaporation ratios, but a variation within 5% is considered acceptable. Results show that acetone presents the most significant influence on co-evaporation ratios. Temperature is also a key factor. Saturated vapor pressure and activity coefficient of the tracer and components in a fraction group affect co-evaporation optimization substantially, indicating that these values are a primary consideration in tracer selection. Finally, the test fuel is applied to an in-cylinder gasoline direct injection fuel mixture distribution measurement using PLIF. Differences between light, medium, and heavy fraction groups are studied under different strategies. Cycle-to-cycle variation analysis shows that the influence of absorption attenuation of the aromatic is distinct in a typical stratified strategy. In the area near the spark plug, cycle-to-cycle variation decreases as injection is delayed.     

甲醇—甲缩醛—甲醛—水四元系的汽液平衡

检验报文献（１）热力学模型的准确性，并用该模型推算了难于测定的甲醇－醛、甲缩醛－甲醛及甲醇－甲缩醛－甲醛的汽液平衡。