Chitosan-based membranes preparation and applications: Challenges and opportunities

Chitosan is an abundant natural biopolymer which finds a variety of applications due to its functionalization extending to pharmacology, controlled drug delivery, healing materials, biomedical engineering, food industry, agriculture, catalysis, biosorbents, wastewater treatment, etc. Chitosan can be transformed to distinct derivatives and composites and be modified and grafted for specific use. Many products like flakes, fine powders, beads, membranes, sponges, fibers, and gels can be formed from chitosan. Degradable membranes made of chitosan in conjunction with other materials have increased their scope and include adsorptive membranes for heavy metal and dyes, biomedical applications of chitosan electrospun nanofibers, metal complexation, polymer and modified chitosan-based nanocomposites, cellulose and chitosan composites in wastewater treatment, fuel cells and catalysis. The review has focused on a number of issues related to the said areas. Application of these composite membranes with real industrial effluents should be done with reference to the commercial adsorbents and then their application for removal of aromatics, oils, surfactants, etc. will become practical. The review covers existing gaps and gives future scope for research and innovation.