Abstract: Three different platinum-rhenium reforming catalysts were prepared by conventional reduction and presulfurization, sulfur injection at low temperature during reduction and the sulfate impregnation method，respectively. The performance of dehydrocyclization of n-heptane over the three catalysts was investigated using n-heptanes as a model compound. The catalysts were characterized by TPR and pyridine adsorption Fourier-transform infrared to test the effect of sulfur introduced by different ways on the performance of dehydrocyclization of n-heptane. The results show that the catalysts prepared by sulfur injection at low temperature during reduction and the sulfate impregnation method exhibit better aromatics yields and selectivities compared to the catalyst prepared by conventional method. Especially the catalyst prepared by sulfate impregnation method reveals the highest aromatics yield and selectivity.

Key words: reforming, sulfur, n-heptane, dehydrocyclization