Synthesis and evaluation of Cu-based catalysts employed in the medium temperature water gas shift reaction

• Published in: International journal of hydrogen energy 2025-02, Vol.101, p.139-147
• Main Authors: Tonekaboni, Mohammad Falsafi, Rezaei, Mehran, Alavi, Seyed Mehdi, Akbari, Ehsan
• Format: Article
• Language: English
• Subjects: CuO–Al2O3 catalyst; Hydrogen purification; Medium temperature shift (MTS)
• ISSN: 0360-3199
• DOI: 10.1016/j.ijhydene.2024.12.352

The Water Gas Shift Reaction (WGSR) is a crucial step for reducing the carbon monoxide (CO) content in the reformate stream to produce purified hydrogen utilized in fuel cell processors. In this paper, CuO–Al2O3 is proposed as an applicable catalyst for medium temperature WGSR (150–400 °C). An optimum CO conversion of 64.5% was achieved at 400 °C using the catalyst containing 40 wt% CuO, synthesized via the co-precipitation method. At this composition, the BET surface area and particle size reach to 108 m2 g−1 and 11.2 nm, respectively. However, beyond the mentioned loading, catalytic performance was declined. The results revealed that CuO(40)-Al2O3 experienced a decreasing trend in CO conversion at 400 °C, from 64.5 to 55.4%, as the calcination temperature increased from 400 to 500 °C. This phenomenon is attributed to the lower reducibility and agglomeration of the Cu species, as confirmed by TPR and XRD analysis. The effects of processing parameters, such as GHSV and the steam/dry (S/D) gas ratio, were also evaluated. Higher S/D ratio (0.7) and lower GHSV (120000 ml h−1 g−1cat) contributed to achieving a higher CO conversion rate. •The CuO–Al2O3 catalysts were fabricated via co-precipitation method.•The CuO (10–50) wt.% -Al2O3 catalysts were tested in the medium temperature shift.•The best performance was achieved at a copper oxide content of 40 wt%.