Synthesis and characterization of Ni_2−xPd_xMnO₄/γ-Al₂O₃ catalysts for hydrogen production via propane steam reforming

다국어 초록 (Multilingual Abstract)

<P><B>Abstract</B></P> <P>Much attention has been paid to the development of environmentally friendly next-generation energy sources, such as hydrogen gas. In this context, propane steam reforming has emerged as one of the most promising approaches. Here, we report the synthesis of various Ni<SUB>2−x</SUB>Pd<SUB>x</SUB>MnO<SUB>4</SUB>/γ-Al<SUB>2</SUB>O<SUB>3</SUB> (x = 0, 0.01, 0.02, 0.03, 0.04, and 0.05) catalysts by sol-gel and impregnation methods and their application in steam reforming of propane (H<SUB>2</SUB>O/C<SUB>3</SUB>H<SUB>8</SUB> = 6/1), doubly promoted by Pd and Ni. The introduction of Pd in Ni<SUB>2−x</SUB>Pd<SUB>x</SUB>MnO<SUB>4</SUB>/γ-Al<SUB>2</SUB>O<SUB>3</SUB> improved catalyst dispersion and reduction of Ni oxides. Ni<SUB>2−x</SUB>Pd<SUB>x</SUB>MnO<SUB>4</SUB>/γ<B>-</B>Al<SUB>2</SUB>O<SUB>3</SUB> catalysts showed different adsorption abilities for C<SUB>3</SUB>H<SUB>8</SUB>, CO, and H<SUB>2</SUB>O gases, which resulted in different catalytic behaviors in steam reforming of propane. This was presumably dependent on the Pd content, and the optimal Pd mole concentration was found to be 4%. Complete conversion of propane and the highest hydrogen selectivity were achieved over Ni<SUB>1.96</SUB>Pd<SUB>0.04</SUB>MnO<SUB>4</SUB>/γ<B>-</B>Al<SUB>2</SUB>O<SUB>3</SUB> at 700 °C. The presence of Pd decreased the evolution of CO, which is responsible for catalyst degradation, and the catalyst maintained a high performance even after five catalytic cycles.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Synthesized Ni<SUB>2−x</SUB>Pd<SUB>x</SUB>MnO<SUB>4</SUB>/γ-Al<SUB>2</SUB>O<SUB>3</SUB> for propane steam reforming. </LI> <LI> Depending on gas adsorption abilities catalytic behaviors are different. </LI> <LI> The optimal Pd mole concentration was found to be 4%. </LI> <LI> The highest hydrogen selectivity was achieved over Ni<SUB>1.96</SUB>Pd<SUB>0.04</SUB>MnO<SUB>4</SUB>/γ<B>-</B>Al<SUB>2</SUB>O<SUB>3</SUB>. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>