Fabrication of hydrochar based on food waste (FWHTC) and its application in aqueous solution rare earth ions adsorptive removal: Process, mechanisms and disposal methodology

摘要: Abstract Hydrothermal carbonization (HTC) of food waste is a promising technology to dispose these widely generated and notorious wastes. Food hydrochar (FWHTC) was produced during this process. However, production application FWHTC remained at embryo stage. Herein, study for the first time leftover steamed bread (LSHTC) pitaya peel (PPHTC), then applied them adsorptive remove rare earth ions (REI) from wastewater. FWHTCs were systematically characterized by SEM, FTIR, XPS, BET, elemental analysis TG-DSC. Isotherm showed that Langmuir model fitted data well lower initial REI concentrations while Freundlich better higher concentrations. The maximum adsorption capacity LSHTC La3+ reached 108 mg g−1. Continuous experiment in column also conducted key operation parameters predicted Yoon-Nelson model. mechanisms dominated physisorption (electrostatic attraction) very starting stage, followed chemisorption (ion exchange and/or surface complexation) playing role. At last, sustainable “Reduce-Reuse-Recycle” pattern disposal methodology proposed.