Poly（amide-6-b-ethylene oxide）/SAPO-34 mixed matrix membrane for CO2 separation

摘要

In this paper, poly(amide-6-b-ethylene oxide)(Pebax1657)/SAPO-34 mixed matrix membranes(MMMs) were prepared by solvent-evaporation method with acetic acid as a novel solvent. CO2, N2, CH4and H2permeation properties were investigated, and the physical properties of Pebax/SAPO-34 MMMs were characterized by XRD and SEM. At low SAPO-34 content, it was homogeneously distributed in the Pebax matrix, and then precipitated and agglomerated at high SAPO-34 content. The crystallinity of Pebax phase in Pebax/SAPO-34 MMMs decreased initially and then rebounded as a result of phase separation. With the increase of transmembrane pressure difference, CO2permeability was enhanced due to the effect of pressure-induced plasticization. Owing to the happening of stratification, the CO2permeability of Pebax/SAPO-34MMMs(50 wt% SAPO-34) increased to 338 Barrer from 111 Barrer of pristine Pebax, while the selectivities of CO2/CH4and CO2/N2were almost unchanged. Compared with the pristine Pebax, the gas separation performances of Pebax/SAPO-34 MMMs were remarkably enhanced.