氯苯类化合物在盐水溶液中的活度系数

STUDIES ON ACTIVITY COEFICIENTS OF CHLOROBENZENE SYSTEM IN AQUEOUS SALT SOLUTIONS

在25.00±0.01℃下用紫外、可见分光光度法分别测定了氯苯(CB)、m-二氯苯(mDCB)、p-二氯苯(pDCB)、1,2,4-三氯苯(TCB)在NaCl、KCl、Na_2CO_3、K_2SO_4、CaCl_2盐水溶液及氯苯在Et_4NBr 水溶液中的话度系数,得出盐效应常数.除Et_4NBr 对氯苯呈盐溶作用,其余均为盐析作用.盐析次序大致为K_2SO_4>Na_2CO_3>CaCl_2>NaCl>KCl.计算了盐效应常数的各种理论值,与实验值进行比较,进一步证实了改进后的内压力理论值更接近实际.同时也讨论了这些数据在环保中的应用.

The activity coefficients of chlorobenzene,m-,p-dichlorobenzene and 1,2,4-tri-chlorobenzene in NaCl,KCl,Na_2CO_3,K_2SO_4 and CaCl_2 aqueous salt solutions,andchlorobenzcne in Et_4NBr have been determined at 298.15K by spectrophotometry.The chlorobenzene in Et_4NBr aqueous salt solution is salting-in,while others aresalting-out.The experimentsl salting-out orders are as follows:K_2SO_4>Na_2Co_3>CaCl_2>NaCl>KCl.These results are compared with the calculated results of Debye-McAulay and Conway-Desnoyers-Smith electrostatic theories;Masterton-Lee scaledparticle theory.MeDevit-Long internal pressure theory and modified internal pressuretheory.It is verified that the modified internal pressure theory coincides with theexperimental value better.