Heavy metal removal from wastewater using various adsorbents: a review
The research paper provides a comprehensive review of the methods and materials used for the removal of heavy metals from wastewater, focusing on the adsorption process. Heavy metals, such as lead, zinc, copper, arsenic, cadmium, chromium, nickel, and mercury, are highlighted as significant pollutants originating from various industrial activities. These metals pose serious health risks to humans and aquatic ecosystems due to their toxic and carcinogenic properties.
The review emphasizes the adsorption process as a preferred method for heavy metal removal due to its cost-effectiveness, availability, and eco-friendliness compared to other methods like chemical oxidation, ion exchange, and reverse osmosis, which often generate sludge and have high operational costs. The authors categorize adsorbents into commercial and bioadsorbents, detailing their effectiveness in removing specific metals like chromium, cadmium, and copper.
Commercial adsorbents such as activated carbon, silica gel, and alumina are discussed, along with their high removal capacities but higher costs. In contrast, bioadsorbents derived from agricultural waste, such as rice husk, coconut coir, and various plant materials, are presented as low-cost alternatives with significant potential for heavy metal adsorption. The article also reviews various studies that demonstrate the effectiveness of these adsorbents, providing data on their adsorption capacities, optimal pH levels, and contact times.
The review concludes by highlighting the need for further research to enhance the efficiency of bioadsorbents, focusing on their modification, regeneration, and application at a commercial scale. The authors stress the importance of optimizing conditions for maximum adsorption efficiency and the economic feasibility of using bioadsorbents in wastewater treatment.
This research paper is significant in the field of environmental science and engineering, particularly in wastewater treatment. It contributes to ongoing discussions about sustainable practices for heavy metal removal, emphasizing the potential of low-cost bioadsorbents derived from agricultural waste. The findings can guide researchers and practitioners in selecting appropriate materials for wastewater treatment, promoting eco-friendly solutions that align with global sustainability goals. The review also serves as a valuable resource for future studies aimed at improving the efficiency and applicability of bioadsorbents in real-world scenarios.
