Promoting dry reforming of methaneviabifunctional NiO/dolomite catalysts for production of hydrogen-rich syngas

• Main Authors: Mohd Razali Shamsuddin, Nurul Asikin-Mijan, Tengku Sharifah Marliza, Manabu Miyamoto, Shigeyuki Uemiya, Mohd Ambar Yarmo, Yap, Taufiq Yun Hin
• Format: Article
• Language: English; English
• Published: Royal Society of Chemistry 2021
• Subjects: TP1-1185 Chemical technology
• Online Access: https://eprints.ums.edu.my/id/eprint/32684/1/Promoting%20dry%20reforming%20of%20methaneviabifunctional%20_ABSTRACT.pdf; https://eprints.ums.edu.my/id/eprint/32684/2/Promoting%20dry%20reforming%20of%20methaneviabifunctional%20NiO.pdf; https://eprints.ums.edu.my/id/eprint/32684/; https://pubs.rsc.org/en/content/articlelanding/2021/ra/d0ra09246k; https://doi.org/10.1039/D0RA09246K

Extensive effort has been focused on the advancement of an efficient catalyst for CO2 reforming of CH4 to achieve optimum catalytic activity together with cost-effectiveness and high resistance to catalyst deactivation. In this study, for the first time, a new catalytic support/catalyst system of bifunctional NiO/dolomite has been synthesized by a wet impregnation method using low-cost materials, and it shows unique performance in terms of amphoteric sites and self-reduction properties. The catalysts were loaded into a continuous micro-reactor equipped with an online GC-TCD system. The reaction was carried out with a gas mixture consisting of CH4 and CO2 in the ratio of 1 : 1 flowing 30 ml min-1 at 800 °C for 10 h. The physicochemical properties of the synthesized catalysts were determined by various methods including X-ray diffraction (XRD), N2 adsorption–desorption, H2 temperature-programmed reduction (H2-TPR), temperature-programmed desorption of CO2 (TPD-CO2), and temperature-programmed desorption of NH3 (TPD-NH3). The highest catalytic performance of the DRM reaction was shown by the 10% NiO/dolomite catalyst (CH4 & CO2 conversion, χCH4; χCO2 ~ 98% and H2 selectivity, SH2 ¼ 75%; H2/CO ~ 1 : 1 respectively). Bifunctional properties of amphoteric sites on the catalyst and self-reduction behaviour of the NiO/dolomite catalyst improved dry reforming of the CH4 process by enhancing CH4 and CO2 conversion without involving a catalyst reduction step, and the catalyst was constantly active for more than 10 h.