Immobilization of biogenic silver–copper nanoparticles over arylated biochar from sugarcane bagasse: Method and catalytic performance
Youssef Snoussi, Mohamed El Garah, Ahmed M. Khalil, Souad Ammar, Mohamed M. Chehimi
Abstract
There is an ever‐growing demand for biochar production and its chemical transformation into specialty materials. Herein, we suggest a versatile method to elaborate Ag/Cu nanoparticles, by phytochemical process, on aryl‐sulfonated sugarcane bagasse pulp‐derived biochar. A binary nanocomposite has been fabricated through a four‐step strategy. The raw substrate biochar was first prepared by a slow pyrolysis of the biomass at 500°C under N 2 :H 2 95%:5% inert atmosphere. Thereafter, in situ arylation of the biochar surface has been performed to obtain SO 3 H‐Biochar. The loading of silver and copper ions on SO 3 H‐Biochar has been achieved via a wet impregnation using a hydroalcoholic medium. Finally, the natural extract obtained from sugarcane bagasse has been employed to ensure the reduction of the adsorbed metal ions and obtain SO 3 H‐Biochar@Ag/Cu. Interestingly, the structural analysis of SO 3 H‐Biochar@Ag/Cu and the study of the evolution of D to G band intensity and area ratios have revealed that the metal phase deposition has altered the SO 3 H‐Biochar surface properties. It finally provided a more graphitized nanocomposite compared with the bare biochar and the intermediate substrate (SO 3 H‐Biochar). Such a result suggests that the phytochemical reduction has catalyzed the substrate graphitization. The catalytic performance of SO 3 H‐Biochar@Ag/Cu has been investigated in the oxidative degradation of malachite green oxalate. A total mineralization of the dye has been registered, and the experimental data were found to give a best fitting to the pseudo‐first‐order model. The fitting was relatively good with a mineralization apparent constant rate equals to 65 10 −3 min −1 . It is worth mentioning that all experiments used a relatively low amount of the composite catalyst (2.5 mg). So to recap, this route takes advantage of the two phases of sugarcane bagasse to generate a robust biochar‐based catalyst, its solid phase to derive biochar substrate with particular properties, and its liquid extract to be used as natural reducing preparation.