Fabrication of Ni-Al2O3-based reforming catalyst using flame-assisted vapour deposition

The fabrication of Ni-Al2O3-based catalysts is often expensive and laboriou s. Flame-assisted vapour deposition (FAVD) offers a simple and cost-effecti ve alternative. The FAVD method combines spray pyrolysis and flame synthesi s techniques to produce simple, mixed and doped oxide coatings. In this stu dy, FAVD is used to produce Ni-Al2O3-based catalysts for use in direct inte rnal reforming of molten carbonate fuel (MCFC). The catalyst produced using FAVD was found to have sufficiently high surface area and porosity require d for the internal reforming of high-methane-containing natural gas to fuel gas. Elemental mapping of Ni also showed a uniform distribution of Ni over the surface of the catalyst. In addition, the required chemical phase in t he coating was obtained in a single-step deposition. The catalysts produced by the FAVD method were sufficiently robust to withstand flaking and delam ination during exposure to the simulated elevated operating temperatures of the MCFC. Ni-Al2O3-based catalysts have been successfully produced using F AVD with acceptable microstructural, chemical and mechanical properties at a lower cost of production and higher deposition rate than those fabricated via conventional routes. The deposition mechanism of the FAVD process is d iscussed. Porous catalysts with good adhesion could be deposited by tailori ng heterogeneous and homogenous reactions during the deposition. (C) 2000 P ublished by Elsevier Science S.A.