Efficient catalytic deoxygenation with a Zr-modified Pd-based industrial catalyst

Abstract

Mitigating the risks of combustion and explosion by injecting inert gases to lower oxygen concentration is a feasible method; however, this approach merely reduces the oxygen concentration without completely resolving the oxygen issue. Efficient catalytic deoxygenation is an effective method, but the successful preparation of industrial-grade catalysts is still a significant challenge. Herein, industrial Pd-based catalysts, modified with Zr, Ce and Cu promoters, are employed to study the promoter effect via a probe reaction of oxygen removal under propylene and hydrogen atmospheres. Combining various characterization results and density functional theory (DFT) calculations, it is found that the Zr promoter promoted the formation of oxygen vacancies, effectively improving the adsorption and activation ability of oxygen. Significantly, the DFT calculation results further demonstrated that Zr–Pd/Al₂O₃ facilitated the desorption of C₃H₆, which played an important role in decreasing the reaction probability of H₂ and C₃H₆, thereby lowering the selectivity of C₃H₈. More importantly, we achieved the preparation of a Zr-modified Pd-based industrial catalyst that realized an outstanding performance. This study not only increases our understanding of promoter effects but also offers an effective strategy to design efficient heterogeneous catalysts to mitigate combustion and explosion hazards.