Review on Agrobiowaste-mediated Nanohybrids for Removal of Toxic Heavy Metals from Wastewater

Because of the growing population and the industrial revolution, a significant number of toxic materials including heavy metals (HMs) are being released into the environment, posing harm to humans, the environment, and other living organisms. When these HMs find their way into water sources, they cause water pollution and pose a threat to the ecosystem. As a result, there is an imperative need to eliminate these HMs from the water. Numerous techniques are being employed for water purification, but adsorption is the most economical and efficient method. The present article critically discussed the applications of different adsorbents including agricultural wastes, industrial wastes, biochar, chitosan, aerogel-based adsorbents, geopolymer cement/concrete, carbon-based nanomaterials (NMs), and polymer-supported nanocomposites (NCs) for removal of HMs from wastewater. Removal capacity of some of the adsorbents are tabulated. Effects of dose of adsorbent, contact time, pH, temperature, initial ion concentration and ionic strength on the removal of HMs from water have been explored. Various adsorption isotherm and kinetic models have also been discussed, including the modeling using artificial neural networks. The agrobiowaste-mediated nanohybrids derived from agricultural wastes, industrial wastes, biochar, chitosan, aerogel-based, geopolymer cement/concrete, carbon-based nanomaterials and polymer-supported nanocomposites can be employed as adsorbents for removal of toxic heavy metals ions from wastewater.image