Question

将下面这段文字翻译成英文

甲苯和乙醇都是有机合成中常用的原料，同时也是化工工业中用途非常广的有机溶剂。常压下，甲苯和乙醇会形成共沸混合物，共沸温度为76.9℃，共沸组成中乙醇67.8wt%，常规精馏无法清晰分离。本文采用萃取精馏的方法分离甲苯-乙醇共沸物系，并使用Aspen plus模拟软件进行工艺流程模拟与优化。
首先运用Aspen plus绘制甲苯-乙醇二元物系的气液平衡相图，进行初选萃取剂；采用Flash模块绘制等相对挥发度曲线和残余曲线，选择合适萃取剂并判断其可行性，正丁苯和正丙苯均能有效提高甲苯-乙醇挥发度，达到分离效果。
然后运用Aspen plus对正丁苯和正丙苯作萃取剂分别进行流程模拟，考察了原料和溶剂进料位置、回流比、溶剂进料流率等参数对产品纯度的影响规律，得到合适的操作参数。计算结果表：正丁苯作萃取剂时，萃取精馏塔塔板为20块，萃取剂和原料进料位置分别为第8块和第19块，回流比为1.1，溶剂进料流量为220kg/hr；溶剂回收塔塔板为24块，进料位置为第8块，回流比为2.4，甲苯和乙醇产品的质量分数都达到了99.9%。正丙苯作萃取剂时，萃取精馏塔塔板为35块，萃取剂和原料进料位置分别为第16块和第32块，回流比为2.4，溶剂进料流量为220kg/hr；溶剂回收塔塔板为30块，进料位置为第12块，回流比为4.8，甲苯和乙醇产品的质量分数都达到了99.9%。
最后对两种萃取剂的能耗和经济性进行对比，正丁苯作萃取剂更适合分离甲苯-乙醇共沸物系。

Answer 1

甲苯和乙醇都是有机合成中常用的原料，同时也是化工工业中用途非常广的有机溶剂。常压下，甲苯和乙醇会形成共沸混合物，共沸温度为76.9℃，共沸组成中乙醇67.8wt%，常规精馏无法清晰分离。本文采用萃取精馏的方法分离甲苯-乙醇共沸物系，并使用Aspen plus模拟软件进行工艺流程模拟与优化。
首先运用Aspen plus绘制甲苯-乙醇二元物系的气液平衡相图，进行初选萃取剂；采用Flash模块绘制等相对挥发度曲线和残余曲线，选择合适萃取剂并判断其可行性，正丁苯和正丙苯均能有效提高甲苯-乙醇挥发度，达到分离效果。
然后运用Aspen plus对正丁苯和正丙苯作萃取剂分别进行流程模拟，考察了原料和溶剂进料位置、回流比、溶剂进料流率等参数对产品纯度的影响规律，得到合适的操作参数。计算结果表：正丁苯作萃取剂时，萃取精馏塔塔板为20块，萃取剂和原料进料位置分别为第8块和第19块，回流比为1.1，溶剂进料流量为220kg/hr；溶剂回收塔塔板为24块，进料位置为第8块，回流比为2.4，甲苯和乙醇产品的质量分数都达到了99.9%。正丙苯作萃取剂时，萃取精馏塔塔板为35块，萃取剂和原料进料位置分别为第16块和第32块，回流比为2.4，溶剂进料流量为220kg/hr；溶剂回收塔塔板为30块，进料位置为第12块，回流比为4.8，甲苯和乙醇产品的质量分数都达到了99.9%。
最后对两种萃取剂的能耗和经济性进行对比，正丁苯作萃取剂更适合分离甲苯-乙醇共沸物系。
Toluene and ethanol are commonly used in organic synthesis of raw materials, but also the chemical industry is widely used in organic solvents. Under normal pressure, toluene and ethanol will form an azeotropic mixture, azeotropic temperature of 76.9 ℃, azeotropic composition of ethanol 67.8wt%, conventional distillation can not be clearly separated. In this paper, toluene - ethanol azeotrope was separated by extractive distillation and the process flow was simulated and optimized using Aspen plus simulation software.
Firstly, the gas - liquid equilibrium phase diagram of toluene - ethanol binary system was used to extract the initial extraction agent. The relative volatility curve and residual curve were drawn by Flash module, and the appropriate extraction agent was selected and its feasibility was determined. Benzene and n-propylbenzene can effectively improve the toluene - ethanol volatility, to achieve separation effect.
The effects of parameters such as raw material and solvent feed position, reflux ratio and solvent feed rate on the purity of the product were investigated by using Aspen plus for the extraction of n-butylbenzene and n-propylbenzene as extraction agents. The appropriate operating parameters The Calculated results table: n-butyl benzene as extractant, extractive distillation tower tray 20, extractant and raw material feed position were 8 and 19, the reflux ratio of 1.1, the solvent feed flow of 220kg / Hr; solvent recovery tower for the 24, the feed position for the first eight, the reflux ratio of 2.4, toluene and ethanol products have reached 99.9% of the mass fraction. When the extraction agent is used as the extractant, the extractive distillation column is 35, the extraction agent and the raw material feed position are 16th and 32th respectively, the reflux ratio is 2.4, the solvent feed flow is 220kg / hr, the solvent Recycling tower plate for the 30, the feed position for the first 12, the reflux ratio of 4.8, toluene and ethanol products have reached 99.9% of the mass fraction.
Finally, the energy consumption and economy of the two extractants were compared, and n-butylbenzene was more suitable for the separation of toluene-ethanol azeotrope.