Preparation of bagasse pith-derived biochar for high-efficiency removal of Cr(VI) and further hydrogenation of furfural

Porous biochar was prepared from agricultural and forestry wastes to remove Cr(VI) in sewage, which solved the problem of water pollution and realized the reuse of wastes. Herein, in this work, the bagasse pith residues after alkali pre-extraction have been used as the raw material for preparing porous biochars (BPR-BC), which could be further used for efficiently purifying the simulated Cr(VI) wastewater. The results showed that the as-prepared biochars had an ultra-high specific surface area of 2745.7 m(3)/g and Cr(VI) removal capacity of 185.07 mg/g. The kinetic and isotherms studies were best described by pseudo-second-order model and Langmuir adsorption isotherm model, respectively. The thermodynamic studies showed that the adsorption process was endothermic and spontaneous. Furthermore, based on the concept of "waste to waste," the Cr-contained waste adsorbent by doping Cu has been converted into a bagasse pith residues biochar supported Copper-Chromium catalyst (Cu-CrOx/BPR-BC) for further hydrogenation of furfural. The catalytic experimental result showed that the furfural (1) can be selectively converted into furfuryl alcohol (FOL) and difurfuryl ether (DEF) catalyzed by the prepared Cu-CrOx/BPR-BC catalyst, provided a new idea for the further utilization of Cr(VI) containing adsorbents.