Low-temperature hydrogenation of tetralin over supported noble-metal catalysts in the presence of sulfur

High aromatics content in distillate fuels is undesirable since it lowers the fuel quality and contributes to the formation of environmentally harmful emissions, such as particulate matter and NO_x. A fixed-bed flow reactor system was used for the hydrogenation of tetralin to decalins in the presence of benzothiophene, as a model reaction for the saturation of aromatics in diesel feedstocks. Several noble-metal catalysts were prepared on various supports, including alumina, titania, Y-zeolite, mordenite zeolite, and HZSM-5 zeolite. Y-zeolite supported catalysts exhibited higher sulfur tolerance than any of the other catalysts tested. As the activity of the catalysts decreased as a result of sulfur poisoning, the selectivity to trans-decalin also decreased, while the selectivity to cis-decalin increased. This is an abstract of a paper presented at the 228th ACS National Meeting (Philadelphia, PA 8/22-26/2004).