Preparation of Polyimide Membrane and Its Application in Treatment of Exhausted Unhairing Liquor

摘要

A polyimide membrane has been prepared from the polyamic acid by chemical imidization, and used in the filtration of exhausted unhairing liquor for recovery and reuse of wastewater. The separation performances and chemical stability as well as thermal property of the membrane have been determined. The results show that the membrane has a rejection of 92% of COD, a rejection of 90% of suspended solids and a rejection of 48% of sulfide with a flux of 33L/m2h for exhausted unhairing liquor at 0.09MPa. The membrane exhibits excellent stability in the range of pH3-l 1 with most unhairing chemicals. A reusable wastewater with less organic matter can be obtained by filtration with the polyimide membrane.