Exploring Biochar Production, Modification and its Role as an Adsorbent in Heavy Metal Removal from Wastewater: A Review

Abstract

As industrialization and population expansion have increased, heavy metal poisoning of water has become common, posing substantial dangers to both human health and ecosystems. Untreated wastewater containing toxic compounds discharged by industries such as mining, electroplating, and metal polishing can harm aquatic ecosystem and remain in the environment and accumulate in the food chain, posing long-term ecological and health risks. Biochar, a carbon rich material which is made by pyrolyzing organic waste, has gained popularity as an economical and sustainable alternative for restoration of the environment, notably in wastewater treatment processes. This review investigates the biochar production from agricultural feedstock, focusing on the effects of feedstock selection, different pyrolysis temperature settings, and modification procedures to enhance its physicochemical parameters. It looks at the modification strategies, such as chemical activation to improve biochar's adsorption ability of heavy metals from wastewater and highlighting biochar’s role in a sustainable wastewater treatment.