Platinum-palladium catalysts for methane-fuelled heaters

Abstract

Natural-gas fuelled catalytic heaters are commonly used in heating industrial space and remote location operations. Industrial units typically contain platinum that provides methane combustion at lower temperatures than non-catalytic burning. This work aimed to find a cost-efficient alternative to monometallic platinum catalyst by replacing some of platinum with less expensive palladium, which is also known for methane combustion activity. The task is complicated by non-uniform reactant profiles across the catalytic pad. Several Pd:Pt bimetallic catalysts were prepared by dry impregnation of commercial pads with metal precursors and tested in methane combustion with 5% water presence at two different methane-to-oxygen molar ratios (0.2 and 0.02). Pt1.6Pd catalyst (molar ratio) is recommended to replace monometallic platinum: it provides higher activity than monometallic Pt catalyst at 0.02 CH4-to-O2 ratio. At the 0.2 ratio, its activity is lower than that of Pt, but is sufficient for adequate heater operation.