Advancements, Design, and Improvement Strategies for Modern-era Membranes for the Treatment of Wastewater

Membranes are widely used in industries such as food and beverage, pharmaceuticals, and wastewater treatment plants, among others, to purify and recycle water, separate dissolved substances from the environment, such as organic and inorganic contaminants, and recover valuable materials. Additionally, they may be supported by different materials such as a fibrous network that should be impermeable to substances in a solution. Along with the type of materials, the polymeric membranes may be classified into different groups according to the process and respective usage. They can be divided according to the type of material into organic and inorganic ones, besides the organizational structure of their matrices as isotropic and anisotropic. Organic membranes are made from synthetic organic polymers and the most used in industrial applications are polyethylene (PE), polytetrafluorethylene (PTFE), polyamide (PA), polyvinylidene fluoride (PVDF), polypropylene (PP), polysulfone (PS), regenerated cellulose (RC) and cellulose acetate (CeA). Meanwhile, the main inorganic membranes used in industry technologies are made from materials such as ceramics, silica, zirconia, glass, metals, and zeolites. Regarding the structure of polymeric membranes and their respective matrix, they can be classified as isotropic and anisotropic. This review article will cover the use of different membranes and their role in treatment of wastewater.