Dry (CO2) reforming of methane over zirconium promoted Ni-MgO mixed oxide catalyst: Effect of Zr addition

Dry (CO2) reforming of methane (DRM) for syngas production has gained great attraction since it utilizes two major green house gases (CH4, CO2). However, this process is still far from commercialization due to the catalyst deactivation by coking and metal sintering. In this present work, we have prepared a series of Zr promoted Ni/ MgO catalysts using Incipient wetness impregnatiom (IWI) method and applied for (DRM) reaction at temperature range of 500-800 C. The prepared fresh and spent catalysts were fully characterized with various adsorption and spectroscopic techniques such as XRD, BET-SA, ICP-OES, H-2-TPR, CO2-TPD, N2O-pulse chemisorption, SEM, TEM, TGA and O-2-TPO. Reduced samples TEM analysis revealed that Zr modified catalysts possessed smaller Ni particles size and N2O-pulse chemisorption results showed that Ni dispersion is improved with Zr addition compared to Ni/MgO. In addition, CO2-TPD analysis confirmed that the basicity gradually increases with the addition of Zr and it enhances the CO2 adsorption capacity. DRM experimental results demonstrated that among all the tested catalysts Ni/Zr-3/MgO exhibited remarkable activity and stable con -version with CH4 (78 %), CO2 (91 %) and H-2/CO ratio (0.92) over a period of 70 h time on stream without deactivation. Further, CH4-temperature programmed surface reaction (TPSR) proved that Zr promoter significantly decreases the CH4 dissociation energy which could be due to smaller Ni particles, strong metal-support interaction and high Ni metal dispersion.

Automated summary

This study successfully developed an effective method for synthesizing syngas through dry reforming of methane by using Zr-modified Ni/MgO catalyst. The catalyst exhibited small Ni particle size, good Ni dispersion, and high CO2 adsorption capacity, showing excellent activity and stability in DRM reaction.