Effect of support on the performance of PtRu-based catalysts in oxidative steam reforming of ethanol to produce hydrogen.

Oxidative steam reforming of ethanol (OSRE) to produce hydrogen has been investigated over a series of supported PtRu catalysts, with different supports. Bimetallic PtRu-based catalysts were prepared by the impregnation method using H ₂ PtCl ₆ and RuCl ₃ as precursors. Six supports (reducible oxides of ZrO ₂ , CeO ₂ , and Co ₃ O ₄ , and irreducible oxides of ZnO, Al ₂ O ₃ , and NiO) were chosen to fabricate bimetallic catalysts. The catalytic performance of the OSRE reaction in the series of PtRu-based samples was evaluated using a fixed-bed flow reactor under atmospheric pressure. In front reaction, the catalyst was pre-activated by reduction under 200°C for 3 h. The gas hourly space velocity was adjusted at 66,000 h ^-1 , and the optimal molar ratios of the H ₂ O/EtOH and O ₂ /EtOH feeds were 4.9 and 0.44, respectively. The results indicated that the PtRu supported on the ZrO ₂ and CeO ₂ exhibited superior catalytic performance in the OSRE reaction under a low temperature (a T _R of approximately 320°C) for producing the main products of H ₂ and CO ₂ with lower CO and CH ₄ by-products. Also, it was quite stable during a long time evaluation; the maximum Y _H2 maintained at 4.5-4.2, and the CO distribution approached 3.3-3.5 mol% around 84 h test at 340°C over the PtRu/ZrO ₂ catalyst.
Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
(Copyright © 2022 Tang, Liu, Yu and Wang.)