用减压膜蒸馏法分离AlCl_3-HCl-H_2O体系中盐酸的研究

HCl separation from AlCl_3-HCl-H_2O system by vacuum membrane distillation

对减压膜蒸馏法分离AlCl3 -HCl-H2 O体系中盐酸进行了研究 ,着重考察了下列各种因素的变化对蒸馏液中盐酸浓度、HCl及H2 O通量的影响 :温度 (5 5～ 6 4℃ )、减压侧压力(7.5～ 10 .0kPa)及溶液中AlCl3 浓度 (0～ 80g/L) .实验结果表明 ,随着料液中盐酸浓度的增加 ,HCl通量增加 ,而H2 O通量降低 ;随着料液温度的升高 ,蒸馏液中盐酸浓度增大 ;减压侧压力对蒸馏液的组成基本无影响 ,而仅仅影响HCl及H2 O通量 ;料液中存在AlCl3 有利于HCl的分离 ,可提高蒸馏液的HCl浓度及其通量 ,而且随着AlCl3 浓度的增大 ,趋势更为明显 .实验结果与热力学分析结果一致 .

HCl separation from AlCl_3-HCl-H_2O system by vacuum membrane distillation was studied. The influences of the following variables on hydrochloric acid concentration in the distillate,HCl and H_2O fluxes were investigated:inlet temperature (55～64 ℃)?permeating pressure (7.5～10.0 kPa) and existing salt AlCl_3 and its concentration(0～80 g/L).The results show that with the increase of hydrochloric acid concentration in the feed,the HCl flux goes up while the H_2O flux decreases.The higher the feed temperature is,the larger the hydrochloric acid concentration in the distillate would be.Pressure in the permeate side is shown no influence on hydrochloric acid concentration in the distillate,but only influence on HCl and H_2O fluxes.It was showed that the existence of AlCl_3 in the feed is beneficial to the separation of HCl in the increase of HCl flux,and decrease of H_2O flux.The experimental results agree with the thermodynamic analyses.