Combined H₂O and CO₂ Reforming of CH₄ Over Ca Promoted Ni/Al₂O₃ Catalyst: Enhancement of Ni-CaO Interactions

Methane reforming with the application of combined H₂O and CO₂ is appropriately known as bi-reforming of methane (BRM). The method is promising because it has potential to deliver an alternative energy source and is effective in mitigating greenhouse gases (GHGs). In this study, Ni-based catalyst with 5 wt% supported Al₂O₃ and various Ca (2–4 wt%) loadings were prepared by following the wetness impregnation method. Characterization techniques, including Brunauer-Emmett-Teller (BET) and X-ray diffraction (XRD), were applied to observe prepared catalysts' structural morphology and physicochemical properties. Based on XRD analysis, the CaO-4wt% catalyst exhibited higher crystallinity than the CaO-2wt% catalyst, enabling it to withstand greater forces and take longer to deteriorate. To improve the catalyst activity, CaO was added as a promoter that altered the contact between Ni and Al₂O₃ and modified the properties of the catalysts for an excellent activity. A fixed-bed continuous reactor with a feed ratio CH₄: CO₂: H₂O of 3:1:2 at 1073 K was used to observe the catalysts performance. BRM catalytic reaction at 800 °C having Ni-4CaO/Al₂O₃ catalyst, proved greatly in converting CH₄ and CO₂ with 79.6% and 87.2% respectively during the 6 h reaction.