Electroplating Sludge-Derived Multiple-Metal-Doped Spinel with Superior CO Selectivity in Reverse Water-Gas-Shift Reaction

At present, carbon reduction is one of the hottest topics and CO is the raw source of many industrial products. For the first time, this work reported CO2 conversion to CO with superior selectivity via hydrogenation using an electroplating sludge-derived catalyst. As a result, the optimized catalyst attained a best CO2 conversion of 45.88% and CO selectivity of 99.97% at 600 degrees C. What is more, the catalyst stably maintained a high conversion of 55.39% and selectivity of 99.68% for 100 h at 550 degrees C. At the same time, the total amount of byproducts was less than 0.32%. After detailed characterizations, the catalyst was featured by CuFeMn-doped ZnCr spinel, which had the ability of mild C-O dissociation and weak CO adsorption. After all, above results show that electroplating sludge is a good precursor for the synthesis of spinel for excellent catalytic CO2 conversion to CO.