Slag-based geopolymer microsphere-supported Cu: a low-cost and sustainable catalyst for CO₂ hydrogenation

Abstract

Recent studies on the exploration of sustainable approach by utilizing large-scale waste materials as potential catalyst in the field of heterogeneous catalysis have attracted much attention. Using industrial waste as...

Insight into Electrochemical Promotion of Cu/Co3O4 Catalysts for the Reverse Water Gas Shift Reaction

“…Nevertheless, Cu 2+ increased to 86 % and Cu 0 /Cu 1+ decreased to 14 % in spent sample after polarization, indicating that Cu had changed into a more oxidized state. The satellite structures between 938 and 946 eV characterized the presence of the CuO phase [43] . From Figure 4b, Co 0 and Co 2+,3+ (Co 3 O 4 ) were the main phases in fresh sample and owned 45 % and 40 % area, respectively, while Co 2+ had 15 %.…”

“…The satellite structures between 938 and 946 eV characterized the presence of the CuO phase. [43] From Figure 4b, Co 0 and Co 2 + ,3 + (Co 3 O 4 ) were the main phases in fresh sample and owned 45 % and 40 % area, respectively, while Co 2 + had 15 %. After electrochemical experiments, the lower oxidized state of Co 0 was completely transferred into higher ones in spent sample and Co 2 + phase increased to 42 % accordingly.…”

Recent Advances in the Reverse Water–Gas Conversion Reaction

“…Deng et al [39] explored the mechanism of a Cu−based slag-based geopolymer microsphere (SGS) catalyst in the RWGS reaction and conducted in situ DRIFTS experiments to observe intermediates generated during the catalytic process. The characteristic bands of bicarbonate and carbonate appeared.…”

“…However, since copper is easily sintered or coked, such catalysts are prone to deactivation during the RWGS reaction. In order to overcome these shortcomings, many RGWS reactions catalyzed by Cu-based catalysts have been reported [39,[51][52][53], and we will describe some representative examples in detail.…”

Synergetic effect of metal–support for enhanced performance of the Cu–ZnO–ZrO2/UGSO catalyst for CO2hydrogenation to methanol

“…25 Salient examples of this are CaO rooted from metallurgical wastes and fly ash for biodiesel production, 26,27 iron oxides derived from red mud for hydrogen production 28 and slag-based geopolymer for reverse water-gas shift reaction. 29 Currently, at Rio Tinto Fer & Titane Company situated in Sorel-Tracy (Québec, Canada), the so-called Upgraded Titania-rich slag (UGS®), containing 94.5% of titanium dioxide, is produced from hemo-ilmenite ore (FeTiO 3 -Fe 2 O 3 ) by a high-pressure and high temperature acid leaching process (T > 900 °C and P > 5 bar). 30 At the end of this process, the beads of the metal oxides, containing mainly Fe, Mg, and Al in the form of magnetite (Fe 3 O 4 ), magnesioferrite (MgFe 2 O 4 ), hercynite (FeAl 2 O 4 ) and free periclase (MgOH), are generated, crystalized, discarded, and referred to as UGS oxide (UGSO) residue.…”