(409d) Pure Hydrogen Production Via Methane Catalytic Decomposition on a Ni-Based Catalyst

The CO concentration in the hydrogen stream produced from methane catalytic decomposition (MCD) reaction on Ni-based catalyst has been an interesting topic. In this work, the active and stable Ni based catalysts derived from hydrotalcite-like precursor prepared by coprecipitation method were employed for the MCD reaction. To avoid oxygen impurities in the feed gas, a high purity undiluted methane and two oxygen traps (purchased from Grace Davison Discovery Sciences) were used in the reaction. The effect of the reduction temperature, reaction temperature and metal loading amount on the CO content in the exhaust from MCD reaction were studied. The results show that the reduction temperature has almost no effect on the activities of Ni-Cu-Al catalysts, but the CO formation concentration decreases with the increase of the reduction temperature. The CO concentration and methane conversion of Ni-Cu-Al catalyst both increase with the increase of reaction temperature. The results of metal loading effect on CO formation show that the CO concentration decreases with the increase of Ni loading. Besides, it shows that the oxygen all comes from the support and the incomplete reduction of metal oxide via the long term reaction test performed on 15Ni-3Cu-2Al catalyst. The CO concentration over the 15Ni-3Cu-2Al catalyst at the optimized condition (reduced at 700 ^oC and react at 600 ^oC) is below the tolerance concentration for PEMFCs (10 ppm) after the first hour of the reaction. This work proves the possibility of supply the hydrogen produced from MCD reaction directly to PEMFC.