Papers by Keyword: Nickel Catalysts

Abstract: Carbon deposits play a crucial role in the performance of catalysts, in terms of controlling both reaction selectivity and activity, this is most often manifest through catalyst deactivation. Understanding the structure and electronic properties of the carbon deposits formed on the surface of a catalyst is therefore an importance key. In this study the catalytic performance of Ni based on Y-Zeolite (CBV300) prepared by incipient wetness impregnation. The prepared catalyst was tested in a micro tubular reactor using temperature ranges of 500, 600 and 700 °C at atmospheric pressure, using a total flow rate of 36 ml/min consisting of 2 ml/min of N₂, 17 ml/min of CO₂ and 17 ml/min of CH₄. The calcination was carried out in the range of 500–900 °C. The catalyst is activated inside the reactor using hydrogen gas.The conversion of CH₄ observed over 5wt%Ni/ Y-Zeolite at 700 °C were 59.6%. The supported Ni catalysts were characterized by BET and TG/DTA techniques.

Abstract: Hydrogen production by steam reforming of methane was studied over Ni catalysts supported on CeO₂, Al₂O₃ and CeO₂-Al₂O₃. These catalysts were prepared using the impregnation method and characterized by XRD. The effect of CeO₂ promoter on the catalytic performance of Ni/Al₂O₃ catalyst for methane steam reforming reaction was investigated. In fact, CeO2 had a positive effect on the catalytic activity in this reaction. Experimental results demonstrated that Ni/CeO₂-Al₂O₃ catalyst showed excellent catalytic activity and high reaction performance. In addition, the effects of reaction temperature and metal content on the conversion of CH₄ and H₂/CO ratio were also investigated. Results indicated that CH₄ conversion increased significantly with the increase of the reaction temperature and metal content.

Abstract: Carbon nanotubes have been prepared by CVD from acetylene-argon gaseous system in tubular flow reactor. Acetylene gas was used as the carbon source needed for carbon nanotube growth. Several types of high porosity foam-like Ni substrate were used as catalyst material at pyrolysis temperatures from 673 to 973 K. Influence of the surface morphology of the foam-like Ni substrates on the carbon nanotubes morphology and growth have been studied.