P84 polyimide membranes modified by a tripodal amine for enhanced pervaporation dehydration of acetone

Abstract

In this work we have fabricated P84 asymmetrical flat sheet membranes with a sponge-like structure by carefully formulating the polymer dope, followed by crosslinking the P84 membranes with a tripodal amine (tris(2-aminoethyl)amine (TAEA)) in a methanol solution, combined with heat treatment. The separation performances for acetone dehydration as functions of dope formulation, TAEA crosslinking time and post-annealing duration were further investigated and optimized by using the Taguchi statistical method. The membrane with the best pervaporation performance possessed a high separation factor of 983 with a reasonable flux of 0.658kgm−2h−1. FESEM, FTIR and XPS were employed to elucidate the crosslinking mechanisms and explain the evolution of physicochemical properties and chemistry–performance relationship. A benchmark comparison indicates that the newly developed P84/TAEA crosslinked membrane has good separation performance for acetone dehydration.