The State of the Art on PVDF Membrane Preparation for Membrane Distillation and Membrane Crystallization: Towards the Use of Non-Toxic Solvents.

Most parts of the earth are covered with water, but only 0.3% of it is available to living beings. Industrial growth, fast urbanization, and poor water management have badly affected the water quality. In recent years, a transition has been seen from the traditional (physical, chemical) wastewater treatment methods towards a greener, sustainable, and scalable membrane technology. Even though membrane technology offers a green pathway to address the wastewater treatment issue on a larger scale, the fabrication of polymeric membranes from toxic solvents is an obstacle in making it a fully green method. The concept of green chemistry has encouraged scientists to engage in research for new biodegradable and non-protic solvents to replace with already existing toxic ones. This review outlines the use of non-toxic solvents for the preparation of PVDF membranes and their application in membrane distillation and membrane crystallization.