Efficiency Recycling and Utilization of Phosphate from Wastewater Using LDHs-Modified Biochar

• Published in: International journal of environmental research and public health Vol. 20; no. 4; p. 3051
• Main Authors: Ding, Chunxia, Long, Xiuyu, Zeng, Guangyong, Ouyang, Yu, Lei, Bowen, Zeng, Rongying, Wang, Jing, Zhou, Zhi
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 09.02.2023; MDPI
• Subjects: Adsorbents; Adsorption; Charcoal; Eutrophication; Experiments; Fertilizers; Hydroxides; Ion exchange; Jute; Kinetics; Magnesium; Morphology; Phosphate; Phosphates; Phosphatic fertilizers; Phosphorus; Ratios; Recycling; Scanning electron microscopy; Wastewater; Water; Water Pollutants, Chemical - analysis; Massachusetts; United States > US; Japan; LDHs; phosphate; recycling; biochar; fertilizer
• ISSN: 1660-4601; 1661-7827; 1660-4601
• DOI: 10.3390/ijerph20043051

The excessive application of phosphate fertilizers easily causes water eutrophication. Phosphorus recovery by adsorption is regarded as an effective and simple intervention to control water bodies' eutrophication. In this work, a series of new adsorbents, layered double hydroxides (LDHs)-modified biochar (BC) with different molar ratios of Mg and Fe , were synthesized based on waste jute stalk and used for recycling phosphate from wastewater. The prepared LDHs-BC4 (the molar ratio of Mg/Fe is 4:1) has significantly high adsorption performance, and the recovery rate of phosphate is about 10 times higher than that of the pristine jute stalk BC. The maximum adsorption capacity of LDHs-BC4 for phosphate was 10.64 mg-P/g. The main mechanism of phosphate adsorption mainly includes electrostatic attraction, ion exchange, ligand exchange, and intragranular diffusion. Moreover, the phosphate-adsorbed LDHs-BC4 could promote mung bean growth, which indicated the recovery phosphate from wastewater could be used as a fertilizer.