(460c) Effective Sulfur Tolerant Catalyst for Steam Reforming of Jet Fuel

In the last few decades, there has been a lot of effort to promote hydrogen as an energy carrier, because hydrogen has a higher heating value than other fuels and since it contains no carbon, it cannot produce CO2. Hydrogen also serves as the primary fuel source for fuel cells, desired for use in cars for transportation or for power generation in stationary applications. Although technologies are available to produce hydrogen from various sources, no technologies produce clean hydrogen from liquid hydrocarbon fuels because of problems associated with catalyst deactivation from sulfur poisoning, coking, and sintering.

Given the current fuel infrastructure, the most likely source of hydrogen for the near term will be liquid fuels such as diesel, gasoline, or jet fuel. There is substantial interest in conversion of jet fuel because of its favored position for military applications. Jet fuel is a mixture of various hydrocarbons which can be parafins, olefins, aromatics, and sulfur-containing compounds. Coke formation is a major issue when considering heavy aromatics like naphthalenes. Sulfur poisoning is also critical due to high sulfur content of jet fuel which can range from 100ppm to about 3000ppm. Thus, a catalyst which is resistant to coke formation and is also sulfur tolerant is required for the successful conversion of jet fuel to hydrogen.

This talk will reveal a systematic approach for the development of an effective sulfur tolerant catalyst with high hydrogen yield during steam reforming. We have compared experimental results for jet fuel with that of a simulated jet fuel mixture containing 70% hexadecane, 15% toluene, 10% tetralin and 5% methylnaphthalene by weight was used. Thiophene was used as the source of sulfur. The reactions were carried out at a steam to carbon ratio of 3 and a temperature of 800°C. Various rhodium based catalysts were employed for this study. The effect of support, co-catalyst, and preparation method will be discussed. Catalyst characterization techniques such as TPO, TPR, XRD, TEM and ICP were used to identify the causes of deactivation during steam reforming Thermogravimetric analysis (TGA) was used to measure the amount of coke deposited on the catalyst.