Low-cost adsorbents for heavy metals uptake from contaminated water: a review
The research paper by Sandhya Babel and Tonni Agustiono Kurniawan reviews the technical feasibility of various low-cost adsorbents for the removal of heavy metals from contaminated water, contrasting them with commercial activated carbon. The authors highlight the increasing interest in alternative adsorbents such as chitosan, zeolites, clay, and industrial waste products due to their high adsorption capacities and local availability. The review synthesizes findings from approximately 100 studies, demonstrating that many low-cost adsorbents outperform activated carbon in terms of metal ion removal efficiency.
Chitosan, derived from shellfish waste, exhibits remarkable adsorption capacities for heavy metals like mercury (Hg²⁺), chromium (Cr⁶⁺), and cadmium (Cd²⁺), with values reaching up to 815 mg/g for Hg²⁺. Zeolites, particularly clinoptilolite, also show significant potential, especially for lead (Pb²⁺) and cadmium (Cd²⁺) removal. The article discusses the properties of various adsorbents, including their ion-exchange capabilities, surface area, and the influence of chemical modifications on their performance.
The authors emphasize the economic advantages of using these low-cost materials, which can be sourced locally and require minimal processing. They also note that while activated carbon remains a popular choice, its high cost and the need for complexing agents limit its use in small-scale industries. The review concludes by advocating for further research into the comparative effectiveness and cost-efficiency of these alternative adsorbents, suggesting that their widespread adoption could significantly benefit wastewater treatment practices and environmental sustainability.
This research paper is significant in the field of environmental technology and wastewater treatment as it addresses the pressing issue of heavy metal contamination in water sources. By exploring low-cost alternatives to activated carbon, the authors contribute to ongoing discussions about sustainable and economically viable solutions for water purification. The findings are particularly relevant for developing countries and small industries that may struggle with the high costs associated with traditional treatment methods. The review not only highlights the potential of these materials but also encourages further research and development, which could lead to innovative applications in environmental remediation.
