Peng, et al (2024) Mechanistic investigation of Pb²⁺ adsorption on biochar modified with sodium alginate composite zeolitic imidazolate framework-8. Environmental Science and Pollution Research. https://doi.org/10.1007/s11356-024-33320-y

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In the battle against heavy metal pollution, the development of cost-effective, clean, and efficient methods for treatment is crucial. A recent study highlights the promising use of modified biochar in tackling this environmental challenge, specifically for the immobilization of lead (Pb2+) in contaminated water.

The research focused on a novel biochar composite named SA@ZIF-8/BC, which utilizes sodium alginate (SA) and zeolitic imidazolate framework-8 (ZIF-8) modified corn cob biochar. The modifications significantly enhanced the biochar’s surface area and, consequently, its ability to adsorb lead from solutions. The study revealed that this composite has a superior adsorption capacity—reaching a maximum of 300 mg g−1, which is nearly 2.4 times greater than the unmodified biochar.

Testing showed that the optimal pH for lead adsorption using this material is pH 5, where it follows the pseudo-second-order kinetic model and Langmuir isotherm model. This suggests that the adsorption process is primarily chemisorptive and occurs in a monolayer fashion. Further analysis, particularly X-ray photoelectron spectroscopy (XPS), indicated that hydroxyl and carboxyl groups within the biochar play a significant role in the adsorption process, underscoring the chemical interactions involved in lead capture.

This study indicates a significant advancement in biochar technology, offering an economically viable and effective solution for treating lead-polluted water. The findings open up new avenues for using modified biochar in environmental cleanup efforts, providing a sustainable option to address the persistent issue of heavy metal pollution in water bodies.

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