Efficient reclamation of phosphorus from wetland plant via CaCl2/NaOH-mediated hydrothermal carbonization: insights from the evolution of phosphorus

• DOI: 10.1007/s44246-024-00120-5
• Publication Date: 2024-04-16T08:02:01Z
• Authors: Junxia Wang; Fan Yu; Xutong Wang; Yuting Wang; Zhanjun Cheng; Xiaoqiang Cui; Beibei Yan; Guanyi Chen
• Keywords: Hydrothermal Carbonization

Abstract Hydrothermal carbonization (HTC) of wetland plant could achieve the recovery phosphorus (P) via production P-enriched hydrochar to alleviate crisis phosphate resources, while migration and transformation P should be determined. In this study, Canna indica was derived into through HTC at different temperatures (200°C-260°C) liquid mediums (H 2 O, CaCl , NaOH). The forms were systematically characterized using K-edge X-ray absorption near edge structure (XANES), 31 nuclear magnetic resonance (NMR), sequential extraction. total content in up 23 mg g −1 with mainly inorganic (> 97.8%), rate almost 100% during NaOH-mediated HTC. species, monoester-P soluble orthophosphate (ortho-P), biomass transformed more stable ortho-P hydrochars, which highly dependent on temperature medium. With increasing temperature, Al/Mg-P gradually replaced by Ca/Fe-P. solution facilitated Ca(H PO 4 ) CaHPO elevating Ca/P ratio. While for HTC, hydroxyapatite (74.3%-81.5%), proportion MgHPO elevated temperature. diffusive gradients thin films (DGT) results implied that addition greatly soil available content, further promoted high NaOH These indicate species availability adjusted varying medium reaction provide guidance target design reclamation. Graphical