Highly efficient chitosan-based bio-polymeric membranes embedded with green solvent encapsulated MIL-53(Fe) for methanol/MTBE separation by pervaporation

Abstract

An emerging family of solvents known as deep eutectic solvents has been heralded as a sustainable alternative to traditional solvents. Due to the low compatibility with polymeric materials, the direct use of a deep eutectic solvent (DES) as a solvent is still in the challenging phase. Therefore, we have developed a novel strategy to add DES into the polymer matrix. We have encapsulated MIL-53(Fe) using the choline chloride and ethylene glycol DES mixture and incorporated it into the chitosan polymer matrix. This study prepares chitosan-based biodegradable and sustainable membranes by adding different nanofillers such as DES, MIL-53(Fe), and DES@MIL-53(Fe) for methanol/MTBE azeotropic mixture separation. The prepared nanofillers and bio-degradable membranes are characterized using various analytical techniques such as FESEM, HRTEM, AFM, FTIR, XRD, TGA, XPS, mechanical strength, and wettability. The best separation results are found for the DES@MIL-53(Fe)/CS membranes because the membrane exhibit the characteristic of both components together. The highest total flux and methanol selectivity are observed for the F4 membrane, which is 2329 g m−2 h−1 and 207.06. Based on the surface characteristics and performance study, the DES@MIL-53(Fe)/CS membrane can have better potential in wastewater treatment and other membrane-based separation processes.