新的液相扩散系数模型  

ESTABLISHMENT OF NEW LIQUID DIFFUSIVITY MODEL

作　　者：杨晓宁[1] 马沛生[1] 陈洪钫[1] 

机构地区：[1]天津大学化工系,天津,300072

出　　处：《化工学报》1994年第5期580-588,共9页CIESC Journal

基　　金：国家自然科学基金资助项目

摘　　要：根据统计力学理论与Eyring绝对速率理论,建立了描述液相扩散系数的理论模型。该模型反映了温度、压力及组成对液相扩散系数的影响。基于此模型,建立了关联高压液相自扩散系数与密度关系的模型方程;导出了二元溶液相互扩散系数与浓度关系的计算方程;建立了计算无限稀释扩散系数的方程。通过对实际物系的验证计算,本文所导出的各方程均能很好地关联计算液相扩散系数,并优于文献方程。On the basis of the fundamental theory of statistical mechanics and Eyring's absolute rate theory, a general theoretical model for the description of liquid diffusivity was developed. In this model, the influences of temperature, pressure and composition on liquid diffusivity were comprehensively considered. From the model:① an equation which can be used to correlate liquid self - diffusivity under high pressure was obtained,② a new equation was derived to calculate the mutual diffusivity at different concentrations in binary solutions, ③a general equation was developed for calculating the diffusivity at infinite dilution. All these equations were applied to practical liquid systems and the calculating results showed that the equations proposed has a higher accuracy in calculating liquid diffusivity than those of literature.

关 键 词：统计力学 液相 扩散系数模型 

分 类 号：TQ021.4[化学工程]