A new-generation poly (ether imide sulfone) based solvent resistant ultrafiltration membrane for a sustainable production of silica nanopowder

Abstract

The work presented here demonstrated the feasibility of using a membrane to improve the sustainability of silica nanopowder production. Due to superior chemical resistance, high thermal-oxidative stability, and good processability, poly (ether imide sulfone) has been used for membrane production and modified with amine-functionalized TiO2 nanoparticles. The membrane demonstrated good long-term leaching stability in 40% ethanol and silica synthesis solution and maintained its permeability and rejection characteristics under static and dynamic conditions. Additionally, the high antifouling property of the membrane allowed recovering 99.5% of the nanoparticles. Backwashing with water resulted in a high flux recovery ratio (>93%), and gravity-settling without energy can easily separate silica nanoparticles and water in the backwashing solution. Compared to classical freeze-drying and oven-drying methods, integrating membrane into silica nanopowder production can reduce energy consumption by a factor of 81 and 53. At the same time, the utility cost can be saved by 80% and 69%. Additionally, the solvent and catalyst recovered in the permeate stream can be reused in the synthesis, reducing disposal and purchasing costs. In conclusion, membrane-assisted nanopowder production can minimize the adverse effects caused by commonly used conventional drying methods and make the process more sustainable and environmentally friendly.