Nanostructured bi-metallic biochar: An innovative approach for arsenic (III) removal from contaminated water

• Published in: Environmental chemistry and ecotoxicology 2025, Vol.7, p.10-18
• Main Authors: Choudhury, Tasrina Rabia, Sajib, Md. Sajjad Hossain, Sowrav, Sheikh Fahim Faysal, Khan, Shahidur R., Alam, M. Nur E., Amin, Md. Nurul
• Format: Article
• Language: English
• ISSN: 2590-1826; 2590-1826
• DOI: 10.1016/j.enceco.2024.09.002

Possessing variable valence states, the element Arsenic (As) is intimidating the quality of the ecology and human health severely. In this study, eliminating As (III) from water-based solutions with great efficiency was done using Bagasse-Mn-Al, a sugarcane bagasse-derived biochar impregnated with Mn and Al. The Bagasse-Mn-Al composite yielded higher removal efficiency towards As (III) than the biochar itself. About 89.53 % of As (III) was removed within 65 min maintaining the very first concentration of As (III) at 400 μg/L, initial pH at 2–2.5, and adsorbent dosage at 0.625 g/L. The Bagasse-Mn-Al composite showed an adsorption potential maximum of 54.945 mg/g which is superior to most of the cheaply synthesized metal-impregnated biochar reported. Results from a variety of characterization techniques indicated that the •OH free radical in the Bagasse-Mn-Al composite mainly contributed to the removal of As (III) where oxidation and complexation were the major mechanisms. With high catalytic efficiency, this cost effectively produced metal-coated biochar showed easy and effective separation of As (III) from aqueous solution. Further, this study focuses on the high potential of Bagasse-Mn-Al adsorbent in the treatment of both ground and wastewater. •The Bagasse-Mn-Al (B-Mn-Al) composite can efficiently remove As(III) from arsenic-polluted water.•Characterization revealed that •OH free radicals in the composite are key to As(III) removal through oxidation and complexation.•The pseudo-second-order kinetic model describes the rate of As(III) sorption well.•Langmuir isotherm best fits the data, indicating homogenized monolayer adsorption.