Chanda, et al (2025) Functionalized biocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More from vegetable waste for phosphorus removal from aqueous solution and its potential use as a slow-release fertilizer. Cleaner Materials. https://doi.org/10.1016/j.clema.2024.100287

Researchers have developed a novel method to transform non-edible vegetable waste into biochar for sustainable phosphorus recovery and reuse. Phosphorus, essential for crop growth, often escapes into water systems from agricultural runoff, contributing to environmental issues like eutrophication. With natural phosphorus supplies dwindling, finding effective ways to recycle this critical nutrient is vital.

The study focuses on creating functionalized biochar by co-pyrolyzing vegetable waste with zinc chloride. This treated biochar exhibits a high capacity for phosphorus adsorption, capturing up to 47.83 mg per gram. Once loaded with phosphorus, the biochar acts as a slow-release fertilizer, gradually supplying nutrients over time. Experiments revealed that 42% of the phosphorus is released within 336 hours, making it a practical alternative to conventional fertilizers.

Testing with mung bean plants showed promising results. Plants grown with phosphorus-laden biochar had a 17% higher yield compared to those treated with traditional fertilizers. This biochar also demonstrated better nutrient retention and gradual release, supporting healthy plant growth.

This approach not only recycles waste into valuable agricultural inputs but also aligns with circular economy principles by minimizing waste and reducing reliance on non-renewable resources. By turning kitchen scraps into efficient fertilizers, this innovation offers a sustainable solution to address nutrient recovery and food security challenges.