正戊烷异构化制异戊烷反应热力学分析  

Thermodynamic Analysis on Isomerization of n-Pentane to Isopentane

作　　者：刘洪全[1] 于中伟[1] 马爱增[1] 张秋平[1] 孙义兰[1] 王子健[1] LIU Hongquan;YU Zhongwei;MA Aizeng;ZHANG Qiuping;SUN Yilan;WANG Zijian(Research Institute of Petroleum Processing, SINOPEC, Beijing 100083, China)

机构地区：[1]中国石化石油化工科学研究院,北京100083

出　　处：《石油学报（石油加工）》2020年第3期492-500,共9页Acta Petrolei Sinica(Petroleum Processing Section)

基　　金：中国石油化工股份有限公司项目(118026)资助。

摘　　要：用Soave-Redlich-Kwong(SRK)方程对正戊烷异构化制异戊烷反应进行了系统的热力学分析,得到了不同反应条件下的热力学数据、体系相态、平衡组成和正戊烷平衡异构化率。结果表明:正戊烷异构化属微放热反应,降低反应温度可提高正戊烷的平衡异构化率;在反应温度较高的中温分子筛异构化或固体超强酸异构化反应条件下,反应体系为气相,性质接近理想气体,反应压力和氢/烃摩尔比对反应平衡的影响可以忽略;在反应温度较低的低温异构化反应条件下,反应体系为气相或气-液两相,且非理想性比较明显,反应压力和氢/烃摩尔比对反应平衡的影响不可忽略,适当降低反应压力或提高氢/烃摩尔比均可提高正戊烷平衡异构化率。The thermodynamic behaviors of n-pentane isomerization to isopentane were systematically analyzed using SRK equation,and thermodynamic data,phase state,equilibrium composition and equilibrium isomerization ratio of n-pentane under different reaction conditions were calculated.The results show that the reaction is exothermic and decreasing the reaction temperature favors the increasing of equilibrium isomerization ratio of n-pentane.When the reaction temperature is high(e.g.moderate temperature zeolite-based isomerization or solid superacid isomerization),the reaction system is gas phase and similar to ideal gas.Therefore,the effects of reaction pressure and molar ratio of hydrogen to hydrocarbon(n(H2)/n(HC))on equilibrium isomerization ratio of n-pentane are insignificant.At low reaction temperature(e.g.low temperature isomerization),the reaction system is gas phase or gas-liquid two-phase and shows nonideality.As a result,the influence of reaction pressure and n(H2)/n(HC)on the reaction should not be neglected.The equilibrium isomerization ratio of n-pentane can be increased by decreasing the reaction pressure or increasing n(H2)/n(HC).

关 键 词：正戊烷 异构化 异戊烷 热力学 SRK方程 

分 类 号：O623.11[理学—有机化学] O642.4[理学—化学]