Supported nickel oxide based catalysts of Fe/ Co/ Ni (10: 30: 60)-Al₂O₃ and Pr/ Co/ Ni (5: 35: 60)-Al₂O₃ that were prepared by wetness impregnation method showed potential catalysts for the in-situ reactions of H₂S desulfurization and CO₂ methanation from ambient temperature up to 300 ^oC.  X-ray Photoelectron Spectroscopy revealed Ni₂O₃ and Fe₃O₄ as the surface active components on the Fe/ Co/ Ni (10: 30: 60)-Al₂O₃ catalyst, while Ni₂O₃ and Co₃O₄ on the Pr/ Co/ Ni (5: 35: 60)-Al₂O₃ catalyst.  Energy Dispersive X-ray analysis indicated the presence of 2.7 % and 0.9 % of sulfur on the spent Fe/ Co/ Ni (10: 30: 60)-Al₂O₃ and Pr/ Co/ Ni (5: 35: 60)-Al₂O₃ catalysts, respectively.  N₂ adsorption-desorption analysis showed reduction of 5.5 % on the surface area of the spent Fe/ Co/ Ni (10: 30: 60)-Al₂O₃ catalyst. However, the surface area of the spent Pr/ Co/ Ni (5: 35: 60)-Al₂O₃ catalyst increased by 8.6 %.

Supported nickel oxide based catalysts were prepared by wetness impregnation method for the in-situ reactions of H 2 S desulfurization and CO 2 methanation from ambient temperature up to 300°C. Fe/Co/Ni (10:30:60)-Al 2 O 3 and Pr/Co/Ni (5:35:60)-Al 2 O 3 catalysts were revealed as the most potential catalysts, which yielded 2.9% and 6.1% of CH 4 at reaction temperature of 300°C, respectively. From XPS, Ni 2 O 3 and Fe 3 O 4 were suggested as the surface active components on the Fe/Co/ Ni (10:30:60)-Al 2 O 3 catalyst, while Ni 2 O 3 and Co 3 O 4 on the Pr/Co/Ni (5:35:60)-Al 2 O 3 catalyst.

The objective of this novel catalyst development is to achieve both low temperature and high conversion of sour gases of H 2 S and CO 2 present in the natural gas. The results showed that the conversion of H 2 S to elemental sulfur on all of the potential catalysts was achieved 100 %. However, methanation of CO 2 in the presence of H 2 S yielded 0.7 % CH 4 over Fe/ Zn/ Cu/ Ti-Al 2 O 3 catalyst, 1.1 % CH 4 over Fe/ Zn/ Cu-Al 2 O 3 catalyst and the highest is 6.1 % CH 4 over Pr/ Co/ Ni-Al 2 O 3 catalyst at maximum studied temperature of 300 o C. The catalysts were further characterized by X-rays Photoelectron Spectroscopy and Nitrogen Adsorption analysis. XPS results revealed Ni 2+ ion in the NiO and Ni 3+ in Ni 2 O 3 species, spinel compound of Co 3 O 4 on the Pr/ Co/ Ni-Al 2 O 3 catalyst. N 2 adsorption-desorption analysis illustrated 7.9 % increment of surface area over the spent Pr/ Co/ Ni-Al 2 O 3 catalyst, which assumed to be responsible for the dramatical increased of the methanation activity of this catalyst at the reaction temperature of 300 o C.

No abstract

The objective of this novel catalyst development is to achieve both low temperature and high conversion of sour gases. Supported mixed metal oxide catalysts were prepared by impregnating the catalysts on alumina beads for the in-situ reactions of H2S desulfurization and CO2 methanation from room temperature up to 200oC. The results showed that the 100% conversion of H2S to elemental sulfur for all of the potential catalysts was achieved at 100oC. However, methanation of CO2 in the presence of H2S yielded 0.4% CH4 over Fe/Zn/Cu/Ti-Al2O3 catalyst and 0.7% CH4 over Fe/Zn/Cu-Al2O3 catalyst at maximum studied temperature of 200oC. XPS results indicated that spinel compounds of CuFe2O4 and Fe3O4 act as the active sites on the Fe/Zn/Cu-Al2O3 and Fe/Zn/Cu/Ti-Al2O3 catalysts. The appearance of Fe3+-OH on Fe/Zn/Cu/Ti-Al2O3 catalyst increased its H2S desulfurization activity. N2 adsorption-desorption analysis illustrated that 34% of the surface area of Fe/Zn/Cu-Al2O3 catalyst was reduced while Fe/Zn/Cu/Ti-Al2O3 catalyst showedreduction of 17% after catalytic testing, which indicated the deactivation of the catalysts resulted from sulfur poisoning.