裂解C_5与甲醇合成甲基叔戊基醚反应体系的非理想性

NON-IDEALITY OF SYNTHESIS SYSTEM FOR tert-AMYL METHYL ETHER WITH PYROLYSIS C_5 AND METHANOL

以裂解 C_5和甲醇为原料、QRE 型大孔磺酸树脂为催化剂,研究了合成甲基叔戊基醚反应体系的非理想性。采用 WILSON 活度系数模型,计算了60～70℃各组分的活度系数。理论分析及计算结果表明:在醚化体系中,组分的活度系数主要与该组分摩尔分数有关;由于甲醇的强极性,甲醇的活度系数随其摩尔分数的减小而增大,但均大于3.1;2-甲基-1-丁烯、2甲基-2-丁烯和甲基叔戊基醚的活度系数随组分摩尔分数的增加在0.89～1.19范围内增加;组分的活度系数均随温度的升高而降低,但变化不大。以60℃和70℃的实验数据拟合了组分活度系数表达式,其相关系数均大于0.97,可用于组分活度系数的计算。

Etherifying pyrolysis C5 is one of the most economical methods for producing new reformu- lated gasoline. The non-ideality of the synthesis system for tert-amyl methyl ether with pyrolysis C5 and methanol on a sulfonic ion exchange resin catalyst（QRE）was studied. The activity coefficients of the components in the etherification system at 60 and 70 ℃ were calculated using WILSON activity co- efficient model. The results showed that the activity coefficient of methanol increases remarkably with the decrease of its molar fraction in the system, which is always more than 3.1, because of the high polarity of methanol; the activity coefficients of 2-methyl-l-butene, 2-methyl-2-butene and TAME in- crease （in the range of 0.89 - 1.19） with the increase of their molar fractions. The activity coefficients of the components decrease with increasing the temperature, but the change is unapparent. The main factor influencing the activity coefficients of the components is the molar fractions in the solution. The components＇ activity coefficent expressions were fitted using the experimental data at 60 and 70℃, which are all more than 0.97. The fitted expressions can be used to calculate the components＇ activity coefficients of the etherification system.