Ethanol Dry Reforming over Bimetallic Ni-Containing Catalysts Based on Ceria-Zirconia for Hydrogen Production

Mixed Ce-Zr oxides with a fluorite structure were synthesized by the solvothermal method in a supercritical medium of isopropanol. The prepared mixed oxides Ce0.5Zr0.5O2 and Ce0.75Zr0.25O2 were used as supports for 5 wt%Ni and bimetallic 2.5 wt%Ni+2.5 wt%Co catalysts. The catalysts were fully characterized (specific surface area, morphology, particle size, phase composition, surface atomic composition) and tested in ethanol dry reforming.The dependences of the conversion of C2H5OH and CO2, the yield of CO and H-2, and the H-2/CO ratio were estimated. The effect of the supported metals interaction and the effect of Ce/Zr ratio in the support on the catalytic activity were shown. The presence of nickel in the composition of the catalyst is necessary for high catalytic activity. It has been shown that the addition of cobalt cannot contribute to increase the catalytic activity and stability, but helps to decrease the deposition of carbon and significantly reduces the rate of carbon formation during ethanol dry reforming comparing to the monometallic nickel material.

Automated summary

Mixed Ce-Zr oxides with a fluorite structure were prepared via solvothermal synthesis in supercritical isopropanol. These oxides were used as catalyst supports for Ni and bimetallic Ni+Co catalysts, which were tested in ethanol dry reforming. The catalytic activity was found to depend on the metal support interaction and the Ce/Zr ratio in the support, with the presence of nickel being essential for high activity. Cobalt addition did not enhance activity or stability, but reduced carbon deposition and formation rate.