陶瓷膜分离净化硫氰酸钠工艺研究

采用陶瓷膜分离净化湿法腈纶溶剂硫氰酸钠物料,分析了膜通量随运行时间的衰减变化趋势及浓缩倍数与膜通量衰减的关系,确定了恢复膜通量的方法,比较了不同膜管的分离效果和分离特性。结果表明:陶瓷膜能有效截留硫氰酸钠物料中的杂质,水不溶物去除率大于75%;膜通量都随运行时间的延长而衰减,当平均膜通量低于设计膜通量时,可采用热纯水进行洗脱,使膜通量恢复;当热纯水无法使膜通量恢复,可采用化学方法或更换膜管;不同膜层厚度的膜管对膜通量影响不大,但厚层膜管的分离除杂效果好。

Separation and purification of sodium thiocyanate by ceramic membrane filtration

Sodium thiocyanate as a solvent for wet-spun acrylic fiber was separated and purified by ceramic membrane technique.The attenuation trend of membrane flux with operation time and the relationship between concentration multiple and membrane flux attenuation were analyzed.The membrane flux recovery method was decided.The separation effect and characteristics of different membrane tubes were compared.The results showed that ceramic membrane was able to effectively clean the impurities in sodium thiocyanate and the removal rate of water insoluble substance was above 75%;the membrane flux was decreased with the increase of operation time,and the membrane flux can be recovered by washing with pure hot water when the average membrane flux was lower than the designed value;the membrane tubes should be replaced or treated by some chemical techniques when the membrane flux can not be recovered by pure hot water washing;the membrane thickness did not have great effect on membrane flux,but the thicker membrane provided better impurity cleaning effect.