Polymeric composite membrane fabricated by 2-aminoterephthalic acid chemically cross-linked polyvinylamine for CO2 separation under high temperature

Improvement of the performance of CO 2 separation membrane under high temperature is of great importance in industrial applications. In this work, 2-aminoterephthalic acid (AA) was used to chemically cross-link polyvinylamine (PVAm) to fabricate PVAm-AA aqueous solution. PVAm-AA/polysulfone(PSf) composite membrane was then prepared by coating PVAm-AA aqueous solution on PSf support membrane. Through the chemical cross-linking by AA, the polymer chain mobility was restrained, resulting in the enhancement of thermal stability. The introduction of AA also increased the effective carrier content for CO 2 separation. Therefore, CO 2 permeance and CO 2 /gas selectivity of PVAm-AA/PSf membrane under relatively high temperature were greatly improved. For CO 2 /N 2 mixed gas (15/85 by volume), PVAm-AA/PSf membrane showed a CO 2 permeance of 661 Gas Permeation Unit (GPU) and CO 2 /N 2 selectivity of 95 at 0.3   MPa and 120   °C. Excellent performance stability was shown during the operation for 250   h at 120   °C. Moreover, PVAm-AA/PSf membrane displayed excellent separation performance and thermal stability for the separation of CO 2 /CH 4 and CO 2 /H 2 mixed gases.