超临界CO_2+EtOH+CO+H_2四元体系压力和温度变化规律及超临界性质的研究  

Studies on Relationship Between Temperature and Pressure of the Supercritical CO_2+EtOH+CO+H_2 Quaternary System and Its Super-critical Properties

作　　者：张敬畅[1] 张建军[1] 刘微微[1] 曹维良[1] 

机构地区：[1]北京化工大学理学院,北京100029

出　　处：《高等学校化学学报》2004年第2期330-333,共4页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金 (批准号 :2 0 0 760 0 4);教育部博士学科点基金 (批准号 :2 0 0 0 0 0 10 0 5 )资助

摘　　要：在 5～ 1 1 MPa的范围内 ,利用恒容静态平衡法详细考察了 CO2 密度在 0 .5 42～ 0 .5 90 g/cm3范围的不同组成的超临界 CO2 +Et OH+CO+H2 四元体系的压力和温度的变化规律 ,并测定了相应的临界温度和临界压力 .模拟了超临界丙烯氢甲酰反应体系的相行为 .结果发现 ,CO+H2 加入量的增多可明显改变超临界CO2 +Et OH+CO+H2 四元体系的超临界性质 ,主要表现为该体系的临界温度随着 CO和 H2 摩尔分数的增加而线性降低 ,临界压力随着 CO和 H2 摩尔分数的增加而线性增加 .在相同的 CO和 H2 组成下 ,超临界四元体系的压力随着体系温度的增加而线性增加 ,并且 p-T线的斜率基本相同 .在相同温度下超临界四元体系的压力随着体系中 CO和 H2 摩尔分数的增加线性增加 。The dependent relationship between temperature and pressure of supercritical CO_2+EtOH+ CO+H_2 quaternary system in the pressure range from 5 to 11 MPa in densities of CO_2 ranging from 0.542 to 0.590 g/cm 3 was investigated by the static visual method in a constant volume. The critical temperature and pressure were experimentally determined simultaneously. The molar fraction of ethanol is 0.2% and that of CO and H_2 whose molar ratio is 1∶1 changes from 0 to 4%. The phase behavior of the hydroformylation of propylene in supercritical CO_2 was simulated. It was found that the addition of CO and H_2 could change the supercritical properties of the CO_2+EtOH+CO+H_2 quaternary system obviously. Its critical temperature decreases linearly while its critical pressure increases linearly with the increasing molar fraction of CO and H_2. It was also found that pressure of the quaternary system in definite density of CO_2 increases linearly with increasing temperature and the slopes of p-T lines were basically the same. Simultaneously, pressure of the same quaternary system increases linearly with the increasing molar fraction of CO and H_2 in definite temperature and the rates of change at different temperatures were almost identical.

关 键 词：超临界流体 超临界反应 丙烯 超临界氢甲酰化反应 四元体系 临界压力 临界温度 变化规律 

分 类 号：O623.121[理学—有机化学] O642.5[理学—化学]