Investigation of nickel supported catalysts for the upgrading of brown peat derived gasification products

A gasification test rig was designed in which peat was gasified under nitrogen over a temperature range 25-550 degrees C at 5 degrees C min(-1). The gasification unit resulted in 35.5 wt% of the carbon present in the peat being converted to a volatile fraction. The volatile fraction was transferred to a secondary catalytic reforming reactor at 800 degrees C. The thermal effect of the second reactor resulted in an increase in the CO, CO2 and CH4 content of the volatile fraction, a syngas ratio of 0.75 and a higher heating value (HHV) of 26.5 MJ kg(-1). Several nickel-supported catalysts were investigated with the intention that they should give an increase in the conversion of the condensable hydrocarbons in the volatile fraction to CO, CO2 and CH4, and a resultant gas stream suitable for use in an integrated gasification combined cycle plant (IGCC) (i.e. syngas ratio 2:1, low methane content and better HHV). Alumina-supported nickel catalysts investigated gave the highest activities and co-precipitated Ni/Al catalysts were most active. A Ni/Al 3:17 catalyst increased the conversion of the hydrocarbons to 91.5%, gave a syngas ratio of 1.81:1, increased the HHV by a factor of 5.3 and completely eliminated methane from the gas stream.