Impact of sulfur on catalytic partial oxidation of jet fuel surrogates over Rh/Al2O3

• The CPOX of unmodified jet fuels and its sulfur-containing surrogates were investigated.
• The influence of the main hydrocarbon structure of a jet fuel and the role of sulfur on the syngas selectivity is discussed.
• Sulfur addition leads to a loss in hydrogen selectivity, whereas the carbon-based main product selectivity is not affected.
• The results support a two-staged deactivation process, caused by sulfur addition at lean conditions.

Jet-fuel surrogates with varying composition and sulfur content were partially oxidized over a Rh/Al2O3 honeycomb catalyst. The surrogates consisted of a blend of n-dodecane, 1,2,4-trimethylbenzene, and benzothiophene to represent model mixtures of the main chemical properties of jet fuels. The experiments were performed under quasi-autothermal conditions for three different C/O-ratios in a set-up, specifically designed for fuels with high boiling points. The product distribution significantly changes with sulfur addition showing increased water formation, undesired by-products and a decline in fuel conversion. A steady increase of by-product formation over time on stream leads to coke deposition for fuels with ≥50 mg S per kg fuel. The interplay between sulfur and coke, caused deactivation and its impact on syngas selectivity, fuel conversion, and by-product formation is discussed.