Ethane formation via catalytic low-temperature steam reforming of C3+-alkanes

• 1 wt% Rh/Ce 0.75 Zr 0.25 O 2 catalyst is active in propane steam reforming at 200–300 °C. • Ethane formed during the process can improve fuel characteristics of the gas. • The formation of ethane is explained by propane hydrogenolysis. The present work aims at studying low-temperature steam reforming (LTSR) of model mixtures of flare gases containing C 2 H 6 -C 4 H 10 in methane excess over a highly dispersed Rh-based catalyst. 1 wt% Rh/Ce 0.75 Zr 0.25 O 2 catalyst was prepared by sorption-hydrolytic deposition. Catalytic properties were studied in the LTSR of model fuel gas mixtures at 200–350 °C. The catalysts provided complete conversion of C 2+ -hydrocarbons into CH 4 , CO 2 and H 2 at 320–350 °C. The conversion of propane and heavier alkanes over Rh at low temperature (200–300 °C) allows obtaining high ethane concentrations in the products, which is not observed in the case of nickel catalysts. The influence of hydrogenolysis reaction to ethane formation is discussed. Ethane has a higher calorific value than methane and can compensate the negative effect of the product gas dilution by carbon dioxide and hydrogen that are formed in the reaction. This can be useful for adjusting the fuel properties (calorific value, Wobbe index, methane number) of the resulting gas mixtures.