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Stability and Activity of Rhodium Promoted Nickel-Based Catalysts in Dry Reforming of Methane
oleh: Jehad Saleh, Ahmed Sadeq Al-Fatesh, Ahmed Aidid Ibrahim, Francesco Frusteri, Ahmed Elhag Abasaeed, Anis Hamza Fakeeha, Fahad Albaqi, Khalid Anojaidi, Salwa B. Alreshaidan, Ibrahim Albinali, Abdulrahman A. Al-Rabiah, Abdulaziz Bagabas
Format: | Article |
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Diterbitkan: | MDPI AG 2023-01-01 |
Deskripsi
The rhodium oxide (Rh<sub>2</sub>O<sub>3</sub>) doping effect on the activity and stability of nickel catalysts supported over yttria-stabilized zirconia was examined in dry reforming of methane (DRM) by using a tubular reactor, operated at 800 °C. The catalysts were characterized by using several techniques including nitrogen physisorption, X-ray diffraction, transmission electron microscopy, H<sub>2</sub>-temperature programmed reduction, CO<sub>2</sub>-temperature programmed Desorption, and temperature gravimetric analysis (TGA). The morphology of Ni-YZr was not affected by the addition of Rh<sub>2</sub>O<sub>3</sub>. However, it facilitated the activation of the catalysts and reduced the catalyst’s surface basicity. The addition of 4.0 wt.% Rh<sub>2</sub>O<sub>3</sub> gave the optimum conversions of CH<sub>4</sub> and CO<sub>2</sub> of ~89% and ~92%, respectively. Furthermore, the incorporation of Rh<sub>2</sub>O<sub>3</sub>, in the range of 0.0–4.0 wt.% loading, enhanced DRM and decreased the impact of reverse water gas shift, as inferred by the thermodynamics analysis. TGA revealed that the addition of Rh<sub>2</sub>O<sub>3</sub> diminished the carbon formation on the spent catalysts, and hence, boosted the stability, owing to the potential of rhodium for carbon oxidation through gasification reactions. The 4.0 wt.% Rh<sub>2</sub>O<sub>3</sub> loading gave a 12.5% weight loss of carbon. The TEM images displayed filamentous carbon, confirming the TGA results.