Engineering bifunctional biochar nanocomposites for enhanced phosphorus removal in wastewater treatment: Simultaneous organophosphorus pesticide degradation and targeted phosphate recovery through crystallization.

To address the critical challenges in green and sustainable water resource management, the wastewater resource utilizationhas emerged as a strategic imperative. However, how to skillfully couple the composite technology to treat complex phosphorus wastewater remains a formidable challenge. This study rational design a bifunctional biochar nanocomposite (N-TiO@MBC), synergistically integrating photocatalytic degradation and selective adsorption capabilities for comprehensive phosphorus remediation. The N-TiO@MBC demonstrates exceptional multifunctionality. 1) Rapid photocatalytic conversion of diverse refractory organophosphorus (OPs) into recoverable inorganic phosphorus (IPs) across a broad pH spectrum (3.0-11.0). 2) Superior anti-interference capacity in complex matrices, maintaining above 90 % glyphosate degradation efficiency and 85.3 % phosphate adsorption capacity against competing anions. 3) Robust cyclic stability with less than 8 % performance decay after 5 regeneration cycles. Density functional theory (DFT) calculations coupled with experimental validation elucidate the material dual functionality. The N-TiO through optimized band structure for enhanced radical generation involving O, OH, and O species, while the MBC provides high-affinity phosphate binding sites via Lewis acid-base interactions. This technology establishes a prototype for simultaneous OPs detoxification and phosphate resource recovery, effectively mitigating aquatic toxicity risks while controlling eutrophication potential.