Toward the Next Generation of Sustainable Membranes from Green Chemistry Principles

Abstract

Large-scale membrane technology has been widely implemented and rapidly growing for roughly 40 years. However, considering its entire life cycle, there are aspects being characterized by low sustainability, and this industry certainly cannot be defined as green. In the membrane manufacturing process, raw materials mainly rely on nonbiodegradable petroleum-based polymers and hazardous solvents. These materials are thus associated with the energy crisis and with disposal burdens at the end of their lifetime, and they pose risks to workers and the environment. Therefore, biobased polymers and green solvents should be employed within the membrane preparation process and replace traditional ones. Moreover, the wastewater generated from membrane fabrication processes contains an important amount of organic solvents and should be efficiently treated or recycled before discharge. The application of artificial intelligence in membrane manufacturing and use processes can also improve efficiency significantly. Finally, a large number of spent membrane elements should also be reused and recovered, rather than landfilled. This review critically evaluates the recent advances in methods to improve the sustainability of membrane technology, specifically emphasizing the progresses made, with regard to the above aspects. This review thus analyzes the needs for membrane industry transformations in the light of circular economy.

Waste Reutilization in Polymeric Membrane Fabrication: A New Direction in Membranes for Separation

“…In line with the call of sustainable membrane production using the green chemistry principle [167], more efforts should also be directed to the establishment of less energy intensive waste processes using less toxic solvent at low quantity and low concentration. Polymeric membrane manufacturing is still generally far from sustainable and environmentally friendly [168].…”

Poly(vinyl alcohol)‐based membranes for fuel cell and water treatment applications: A review on recent advancements

“…With the explosive growth in human population and anthropogenic activities, consumption of energy and pure water has been increasing day‐by‐day. Membrane‐based processes offer sustainable solution to the increasing demand of energy and pure water 1–3 . Membrane plays key roles in fuel cells for energy generation and in membrane processes for water filtration.…”

Cellulose Film with Air Barrier and Moisture-Conducting Character Fabricated by a Green Process

“…A thin lm is a layer of material ranging from fractions of a nanometer to several micrometers in thickness, has been increasingly applied in diverse elds, such as separation, chemicals, pharmaceuticals, food, textiles, biomedicine, etc. (Xie et al, 2021;Nunes et al, 2020;Xu et al, 2018;Yang Zhang et al, 2018). However, the preparation of thin lm materials in the traditional sense usually uses petroleum-based as the basic raw material.…”

“…However, the preparation of thin lm materials in the traditional sense usually uses petroleum-based as the basic raw material. In addition, a large number of toxic organic solvents are involved in the processing (Xie et al, 2021). Although this kind of lm can meet the production requirements, its further development is restricted due to their non-degradability and unsustainability production process.…”