A super magnetic porous biochar manufactured by potassium ferrate-accelerated hydrothermal carbonization for removal of tetracycline

• Published in: Journal of cleaner production 2024-01, Vol.435, p.140470, Article 140470
• Main Authors: Hang, Jiacheng, Guo, Zijing, Zhong, Caihua, Sun, Ahui, He, Kaili, Liu, Xiang, Song, Hui, Li, Jihui
• Format: Article
• Language: English
• Subjects: Hydrothermal carbonization; Magnetic porous biochar; Nanoscale iron oxides; Oxidative magnetization; Super adsorption capability
• ISSN: 0959-6526; 1879-1786
• DOI: 10.1016/j.jclepro.2023.140470

Hydrothermal carbonization (HTC) is a promising and powerful technology for manufacturing magnetic biochar with abundant functional groups at relatively low temperature. Herein, K2FeO4-accelerated HTC of kelp was studied to manufacture high-performance magnetic biochar for eliminating tetracycline (TC) in aqueous solution. Nanoscale magnetic iron oxides were generated with abundant oxygen containing groups and porous structures as the HTC was performed at 300 °C. This magnetic biochar displayed 1245.43 mg/g adsorption capacity at 35 °C with 56.48 emu/g saturation magnetization. The adsorption was mostly ascribed to hydrogen bonding/coordination/cation exchange of oxygen functional groups and iron oxides. Moreover, K2FeO4-promoted HTC also exhibited good efficiency and generality for manufacturing potent magnetic biochars from different biowastes for eliminating TC in aqueous solution. [Display omitted] •A super adsorption capacity was gained for tetracycline.•Active oxygen functional groups were massively generated.•Nanoscale γ-Fe2O3 and Fe3O4 were doped.•Abundant porous structures were generated.•A superior magnetism was obtained.