Design of iron-ion-doped pomelo peel biochar composites towards removal of organic pollutants

After treated with saturated iron(II) chloride water solution at pH similar to 2, pomelo peel was used as precursor for preparation of 3 biochar composites (named CFe1, CFe2 and CFe3, accordingly) via hydrothermal treatment and followed calcination in air, respectively. The as-obtained C/Fe biochar composites were studied with PXRD, SEM, EDS, UV-visible spectroscopy and specific surface area device to analyze their phase, morphology, composition, capacity for light absorption and specific surface area. Furthermore, the adsorption and photocatalytic performances of the 3 biochar composites on rhodamine B (Rh B) water solution were investigated. The experimental results show that the hydrothermal pomelo peel biochar composites have better adsorption performance in degrading RhB than that obtained from calcining pomelo peel in air, but opposite for the photocatalytic performance. The removal of imidacloprid (a pesticide) from water via CFe1 was also studied.