Structural analysis of crosslinked pbi-based membranes with excellent separation performance and alkaline stability

Abstract

Organic Solvent Nanofiltration (OSN) has garnered significant attention within the petrochemical and pharmaceutical industries, primarily due to its notable advantages in minimizing energy consumption when compared to traditional thermal separation techniques. In this study, polybenzimidazole based membrane was crosslinked to improve its chemical stability and utilized for OSN. Given the prevalent usage of alcohol in petrochemical and pharmaceutical industries, oxygen-enriched crosslinkers featuring varying oxygen content were used to increase alcohol permeance. The distinctions in oxygen content yielded variations in the membrane’s polarity and hydrophilic properties. Therefore, the solvents with high permeance were different and the rejection were similar. Furthermore, the alkaline stability of the membrane under organic solvent environment was assessed, revealing the outstanding stability of both membranes. Additionally, when compared to membranes documented in prior literature, both membranes exhibited superior ethanol permeance and demonstrated efficient separation of smaller compounds.