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Syngas is a valuable entity for downstream liquid fuel production and chemical industries. The efficient production of syngas via catalytic partial oxidation of methane (CPOM) is an important process. In this study, partial oxidation of methane (POM) was carried out using CaO decorated TiO2 catalysts. The catalysts were synthesized employing the sol-gel method, while the decoration of TiO2 with CaO was achieved in an aqueous solution by wetness impregnation method. The prepared catalysts were characterized by employing XRD, Raman, TG-DTG, and SEM-EDX for structural and morphological analysis. On testing for POM, at 750 °C the catalysts demonstrate excellent CH4 conversion of 83.6 and 79.5% for 2% and 3% CaO loaded TiO2, respectively. While the average H2/CO ratio for both 2% and 3% CaO loaded TiO2, 2.25 and 2.28, respectively, remained slightly above the theoretical value (H2/CO = 2.0) of POM. The improved POM performance is attributed to the optimally loaded CaO on the TiO2 surface that promotes the reaction where TiO2 support ensure less agglomerated particles, resulting into a fine distribution of the active catalytic sites. [ABSTRACT FROM AUTHOR]

In this study, biomass fly ash (BFA)-supported Ni/CaO catalyst was synthesized, characterized and evaluated for partial oxidation of methane (POM) in a fixed bed reactor. The catalyst was characterized by using various characterization techniques including X-ray diffraction, scanning electron microscopy, energy dispersive X-ray analysis, thermogravimetric analysis, Fourier transform infrared spectroscopy and RAMAN spectroscopy. These characterizations demonstrated the formation of pure crystalline CaO and BFA with better dispersion of Ni metal over support material, enhancing the thermal stability of catalyst in POM reaction (up to 900 °C). The Ni/CaO-BFA was tested for POM and demonstrated superior catalytic behaviour in CH4 conversion and H2/CO ratio than BFA, CaO and CaO-BFA. Maximum 87% CH4 conversion was achieved by utilizing 10% Ni/CaO-BFA with H2/CO ratio of 2.07 as it is an effective precursor for liquid fuels (FT synthesis) production. The most stable catalyst has shown coke-resisting properties in POM reaction even after 35 h time on stream that was confirmed by the characterization of spent catalyst. Thus, the development of more efficient catalyst prepared from waste materials shows huge potential in POM and possibly in other reforming reactions. [ABSTRACT FROM AUTHOR]

The utilisation of methane (CH 4) to produce syngas (H 2 , CO) via partial oxidation of methane (POM) is an attractive technique, as syngas is a very valuable entity to produce liquid fuels and fuel cell applications. This work presents the hydrothermal growth of ZnO nanoprisms (ZnO-NPr) in a dual solvent for a controlled structure. The Co-Ni loaded ZnO-NPr catalysts were obtained in an aqueous solution by wetness impregnation method and tested for POM for the first time. The synthesized catalysts were characterized by employing XRD, SEM-EDX, TGA and RAMAN spectroscopy for structural and morphological analysis. The catalysts were analyzed for POM at 850 °C and demonstrated high catalytic activity. It was observed that the catalytic activity of Co loaded ZnO-NPr, and Ni-Co loaded ZnO-NPr was more and demonstrated the stable behaviour for CH 4 conversion in comparison to Ni loaded catalysts. The Co-Ni loaded ZnO-NPr has shown a high CH 4 conversion (X CH4) (98%), and excellent stability over 56 h on stream. The average value of H 2 /CO for Co-Ni loaded ZnO-NPr was 2.11, above the theoretical value for POM. It is attributed to the better performance of catalyst towards the selectivity of H 2 in reaction pathways. [Display omitted] • ZnO nanoprisms (NPr) support was successfully synthesized by hydrothermal process. • Bimetallic loaded ZnO-NPr showed shape dependent support effect in POM. • The high reactivity shown due to better interaction of Co and surface of support. • The bimetallic loaded catalyst exhibited excellent stability in POM reaction up to 56 h. [ABSTRACT FROM AUTHOR]