PEBA渗透汽化膜用于分离回收稀水溶液中邻甲酚

摘要

In this paper,PEBA2533 membrane was applied to separate the o-cresol from dilute aqueous solution by pervaporation,and the high-purity o-cresol crystal was recovered by pervapo-ration-fractional condensation process.The surface and cross-section morphology of PEBA2533 membrane were characterized by scanning electron microscopy.The adsorption performance of PEBA2533 membrane toward o-cresol was investigated by the degree of swelling.The separation performance of PEBA2533 membrane for o-cresol was investigated at different feed concentrations and temperatures.The results show that o-cresol flux increased with the increase of feed concen-tration,and the separation factor was in a relative higher range (from 59 to 105)under the feed concentration range from 2 000 to 7 000 mg/L.With the increase of feed temperature,the fluxes of cresol and water increased obviously,and the separation factor also increased gradually.When feed concentration and temperature was 7 000 mg/L and 70 ℃,respactively,o-cresol crystal flux was up to 295.9 g/(m2·h),and the purity was 99.9%.%考察了 PEBA2533渗透汽化膜分离稀水溶液中邻甲酚的性能,并运用渗透汽化-分级冷凝工艺回收高纯度邻甲酚晶体.采用扫描电子显微镜对 PEBA2533膜的表面及断面进行表征,通过膜的溶胀实验考察了 PEBA2533膜对邻甲酚的吸附性能,考察了在不同原料质量浓度及原料液温度时 PEBA2533膜对邻甲酚的分离性能.结果表明:随着原料液浓度增大,邻甲酚的通量不断增大;在原料液质量浓度范围2000~7000 mg/L 内,分离因子处于较高的范围(59~105).随着原料液温度升高,邻甲酚与水的通量均明显增大,同时分离因子也逐渐增大;当原料液质量浓度与温度为7000 mg/L,70 ℃时,邻甲酚晶体通量高达295.9 g/(m2·h),纯度为99.9%.