Industrialization has exacerbated cadmium (Cd) pollution, posing significant environmental and health risks. A recent study explores a novel solution: magnetized bentonite modified rice straw biochar (Fe3O4@B-Bc), designed for efficient Cd(II) adsorption.

Biochar, produced through rice straw pyrolysisPyrolysis is a thermochemical process that converts waste biomass into bio-char, bio-oil, and pyro-gas. It offers significant advantages in waste valorization, turning low-value materials into economically valuable resources. Its versatility allows for tailored products based on operational conditions, presenting itself as a cost-effective and efficient More, was combined with magnetized bentonite clay, activated with KOH, and subjected to further pyrolysis. This process yielded Fe3O4@B-Bc, which effectively addresses the challenge of separating bentonite or biochar from water. The composite demonstrated a maximum Cd(II) adsorption capacity of 241.52 mg/g, outperforming previous modifications of rice straw biochar.

Characterization revealed that Fe3O4@B-Bc’s surface is enriched with carbon, oxygen, and iron functional groups, enhancing its adsorption efficiency. Quantitative analysis indicated that cation exchange and physical adsorption contribute 65.87% of the total adsorption capacity.

This study highlights the composite’s potential as a low-cost, recyclable green adsorbent for treating cadmium-contaminated water. Fe3O4@B-Bc’s high adsorption capacity and ease of separation make it a promising candidate for environmental remediation, offering an innovative approach to managing heavy metal pollution.