Preparation of high specific surface area Zn/Al/Zr LDH@HTCC for enrichment and recovery of phosphorus from water

Abstract

Phosphorus enrichment and recovery from wastewater, as well as its use as fertilizer in agricultural output, is an efficient method of addressing both phosphorus pollution and phosphorus resource scarcity. In this study, Zn/Al/Zr LDH with hydrothermal carbon loading (ZARH) composites were prepared by co-precipitation method and applied to simulate the efficient enrichment of phosphorus in wastewater. The microstructural characterization showed that ZARH-3 composites had a large specific surface area and multiple adsorption sites. Within 120 minutes, ZARH-3 composites could remove 99% phosphorus (25 mg/L). Furthermore, the saturation adsorption capacity of the composites was 26.64 mg/g when pH was 5. Both the Langmuir and Temkin models accurately described the isothermal adsorption data (R2 > 0.99). Finally, zeta potential, XPS, and FT-IR were used to explain the adsorption mechanism of phosphorus by ZARH-3 composites. Results show that phosphorus was enriched by interacting with the composites primarily through ion exchange, electrostatic interaction, and ligand exchange. In conclusion, ZARH-3 composites prepared in this study is a highly efficient adsorbent for phosphorus removal from aqueous solutions. This research can provide scientific basis for the efficient remediation of eutrophication water body containing phosphorus and effective recovery of phosphorus resources.