Rice husk hydrochars from metal chloride-assisted hydrothermal carbonization as biosorbents of organics from aqueous solution

Abstract Hydrochar a carbon-rich material resulting from hydrothermal carbonization of biomass, has received substantial attention because its potential application in various areas such as carbon sequestration, bioenergy production and environmental amelioration. A series hydrochars were prepared by metal chloride-assisted rice husk characterized elemental analysis, zeta potential, X-ray diffraction, Brunauer–Emmett–Teller measurements, Fourier transform infrared spectroscopy, thermogravimetric photoelectron spectroscopy scanning electron microscopy. The results reveal that the have contents ranging 45.01 to 58.71%, BET specific between 13.23 45.97 m 2 /g, rich O-containing functional groups on surfaces. chlorides added feedwater could improve degree show significant effects physical, chemical adsorption properties hydrochars. selected organics is spontaneous physisorption-dominated process. possess larger capacities for 2-naphthol than berberine hydrochloride Congo red, modeling maximum are range 170.1–2680 mg/g. equilibrium be accomplished 10, 40 30 min 2-naphthol, respectively. These suggest promising method converting biomass waste into effective adsorbents wastewater treatment.