Autothermal reforming of n-octane on Ru-based catalysts

Abstract

In an attempt to effectively integrate catalytic partial oxidation (CPO) and steam reforming (SR) reactions on the same catalyst, autothermal reforming (ATR) of n-octane was addressed based on thermodynamic analysis and carried out on a non-pyrophoric catalyst 0.3 wt.% Ru/K 2O-CeO 2/γ-Al 2O 3. The ATR of n-octane was more efficient at the molar ratio of O 2/C 0.35–0.45 and H 2O/C 1.6–2.2 (independent parameters), respectively, and reforming temperature of 750–800 °C (dependent parameter). Among the sophisticated reaction network, the main reaction thread was deducted as: long-chain hydrocarbon → CH 4, short-chain hydrocarbon → CO 2, CO and H 2 formation by steam reforming, although the parallel CPO, decomposition and reverse water gas shift reaction took place on the same catalyst. Low temperature and high steam partial pressure had more positive effect on CH 4 SR to produce CO 2 other than CO. This was verified by the tendency of the outlet reformate to the equilibrium at different operation conditions. Furthermore, the loss of active components and the formation of stable but less active components in the catalyst in the harsh ATR atmosphere firstly make the CO inhibition capability suffer, then eventually aggravated the ATR performance, which was verified by the characterizations of X-ray fluorescence, BET specific surface areas and temperature programmed reduction.