Advancements in Starch‐Based Aerogels and Hydrogels for Treatment of Water Containing Heavy Metals – A Short Review

Abstract

AbstractRapid industrialization and profligate use of resources in the present era has led to increase in the concentration of toxic heavy metal ions in water bodies and has become a serious environmental concern. Starch hydrogels and aerogels with engineered functionality, porosity, regeneration characteristics, and high surface to volume ratio have rendered them potential candidates for the adsorption of heavy metal ions from wastewater streams. However, grafting, crosslinking, and composting of the starch aerogels and hydrogels to tailor them in response to various stimuli such as ionic strength, pH, and temperature has added an advantage in the treatment of wastewater containing heavy metal ions. This review critically analyses the various synthesis routes for the production of starch‐based aerogels and hydrogels with physico‐chemical characteristics (amylose content, gelatinization temperature, surface area, density, and porosity) and their applicability to adsorb heavy metal (Cd, Cu, Co, Ni, Cr, Pb, Zn, Fe, and Co) ions from wastewater. Future prospects in the development of economical and robust starch‐based aerogels and hydrogels in terms of their stability and reusability have also been discussed.