Construction of graphene oxide intercalated with UiO-66-PEI heterostructure membrane for efficient pervaporation dehydration of isopropanol

Abstract

The separation of isopropanol (IPA)-water mixtures is a critical process in chemical, bioprocess, and electronics industries. This study aims to develop a high-performance pervaporation (PV) membrane for IPA-water separation through incorporating UiO-66-PEI into graphene oxide (GO) membrane by leveraging the combined properties of 2D and 3D nanomaterials. Polyethyleneimine (PEI) was grafted into UiO-66-NH2 to synthesize UiO-66-PEI using Schiff base reactions with glutaraldehyde. The UiO-66-PEI was subsequently intercalated into GO layers to fabricate the membrane in hydrolyzed polyacrylonitrile support using pressure filtration. This intercalation significantly impacted the chemical properties and structure of the GO, leading to an enhanced PV performance in IPA-water mixture separation. The resulting membrane demonstrated a remarkable separation efficiency with a permeation flux of 1479 g∙m−2∙h−1 and a high water content in the permeate of 99.60 wt%. Notably, the exceptional separation performance of the nanocomposite membranes was sustained across varying feed concentrations, operating temperatures, and during long-term operational periods. The findings in this work offer valuable insights into the fabrication of GO-based heterostructure membranes with significant implications for advancing PV separation technology.