Wang Q, Wang CY, Zhou HD, Xue DX, Xiong XL, et al. (2024) Simultaneous adsorption of ammonia nitrogen and phosphate on electro-assisted magnesium/aluminum-loaded sludge-based 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 and its utilization as a plant fertilizer. PLOS ONE 19(10): e0311430. https://doi.org/10.1371/journal.pone.0311430

Researchers recently developed an advanced biochar that efficiently removes both ammonia nitrogen and phosphate from wastewater, providing a potential dual benefit as a soil fertilizer. This biochar was created by modifying sludge-based biochar with magnesium and aluminum through an electro-assisted process, resulting in a material with a surface area 11.27 times larger than untreated sludge-based biochar. This increased surface area and metal loading significantly improved the biochar’s adsorption capacity for nitrogen and phosphorus, critical nutrients that, in excess, contribute to water pollution and eutrophication.

The enhanced biochar removes nitrogen and phosphorus simultaneously by promoting the formation of compounds like struvite, a mineral known for trapping these elements. The modified biochar achieved maximum adsorption capacities of 65.19 mg/g for ammonia nitrogen and 92.10 mg/g for phosphate, outperforming unmodified biochar by several times. Moreover, when the nutrient-saturated biochar was added to soil, it supported plant growth, demonstrating a promising recycling method for biochar saturated with wastewater nutrients.

This innovation holds significant promise for wastewater treatment facilities, potentially transforming a waste byproduct into a value-added resource that aids both in water quality improvement and in agriculture. The study suggests that applying such modified biochar to soil can provide a sustainable fertilizer option, promoting crop growth and soil health while addressing pollution challenges.