CO2 reforming of CH4 over Ni-catalyst supported on yttria stabilized zirconia

Abstract

The present work describes the use of yttria stabilized ZrO2 support. Different loadings (5, 10, 15 and 20 wt%) of yttria were used. The catalysts were tested for CH4 reforming with CO2 at 700 °C. The effect of doping Y2O3 with ZrO2 on the catalytic performance was attained. N2 physisorption (BET), X-ray diffraction (XRD), temperature programmed reduction (TPR), thermogravimetric analysis (TGA), and transmission electron microscopy (TEM) were employed to analyze the used and fresh catalysts. The results showed that Y2O3 stabilized ZrO2 supported catalysts generated the better conversions of CH4 and CO2 than nonstabilized ZrO2 supported catalysts. The mean CH4 conversions found were 54%, 59%, 60%, 66% and 65% respectively for the 5Ni-ZrO2, 5Ni-5Y-ZrO2, 5Ni-10Y-ZrO2, 5Ni-15Y-ZrO2 and 5Ni-20Y-ZrO2. The BET output displayed significant rise in the surface area of the Y2O3 satbilized catalysts. The crystallite size of NiO acquired via XRD measurements exhibited remarkable decrease due to the addition of Y2O3. TGA and TEM of the spent catalysts showed respectively, reduction of carbon formation as a result of Y2O3 addition and formation of multisized nano tubes. The experimentation of the best 5Ni-15Y-ZrO2 for 40 h produced 60% weight loss of mass and the formation of amorphous carbon on the surface via TGA and TPO respectively.