Development of Co Supported on Co−Al Spinel Catalysts from Exsolution of Amorphous Co−Al Oxides for Carbon Dioxide Reforming of Methane

In this study, redox exsolution method was used to synthesize Co/Co−Al spinel for dry reforming. The aim is to improve metal‐support interaction, which enhances the catalyst's stability and minimizes carbon deposition. The synthesized catalysts were observed as Co embedded on Co deficient CoAl 2 O 4 ‐like spinel (denoted as Co−Al spinel). The reduction temperature was optimized at 750 °C. Investigations on the effect of Co loading revealed that optimum Co loading is needed to control the Co particle size, providing balance between limiting carbon deposition rate and preventing dissolution of Co into the support. The best performing catalyst, Co‐15, in which the molar ratio of Co and Al is 15 : 85 produced a stable 81.5 % and 87.4 % conversions for CH 4 and CO 2 continuously over 24 h of reaction time with 13.51 wt% of carbon deposition. The strong metal‐support interaction of Co and Co−Al spinel in Co‐15 stabilizes and prevents the sintering of Co particles, enhancing the efficiency for dry reforming reaction.