萃取精馏分离苯-环己烷-环己烯的二元混合溶剂研究

采用N,N-二甲基乙酰胺(DMAC)、N-甲基吡咯烷酮(NMP)和γ-丁内酯萃取分离苯-环己烷-环己烯近沸程物系,考察了3种单一溶剂的分离性能,数据表明DMAC性能相对更优。在此基础上,研究了以DMAC为基础溶剂,NMP和γ-丁内酯为助溶剂的二元混合溶剂对苯-环己烷-环己烯物系的分离性能,结果表明:混合溶剂提高了从环己烷-环己烯中萃取分离苯的能力,但增大了从环己烷中分离环己烯的难度。当NMP和γ-丁内酯在二元混合溶剂中的质量分数分别为10%和25%时,其分离性能优于单一溶剂,整体分离效果也达到最优。

Study on binary mixed solvents for separating benzene-cyclohexane-cyclohexene by extractive distillation

N,N-dimethyl acetamide(DMAC),N-methyl pyrrolidone(NMP) and γ-butyrolactone were chosen to separate benzene-cyclohexane-cyclohexene by extractive distillation.The separation performance of the three solvents was investigated respectively.The results show that DMAC is superior to NMP and γ-butyrolactone.On that basis,the separation performance of binary mixed solvents(DMAC as basic solvent and NMP,γ-butyrolactone as cosolvent separately) was studied.The results show that it is easier to separate benzene from cyclohexane-cyclohexene,but more difficult to extract cyclohexene from cyclohexane.When the mass fraction of NMP and γ-butyrolactone in the binary mixed solvents is 10% and 25% respectively,the separation performance is better than that of single solvent and achieves the best.