Gas phase hydrodesulfurization of JP-8 light fractions using steam reformate

PETR 58

David L King, david.king@pnl.gov, Institute for Interfacial Catalysis, Pacific Northwest National Laboratory, P.O. Box 999, Richland, WA 99352 and Xiwen Huang, xiwen.huang@pnl.gov, Energy Science and Technology Directorate, Pacific Northwest National Laboratory, P.O. Box 999, Richland, WA 99352.
Detailed parametric investigations were performed on hydrodesulfurization (HDS) processing of a JP8 light cut. The uniqueness to the approach of this work is the utilization of steam reformate (syngas) derived from desulfurized JP8 rather than pure H2 as gas feed to the HDS unit. Also, the HDS process is operated in the gas phase at low or moderate pressure and high space velocity, in contrast to the conventional operation in three-phase trickle bed under high pressure. JP8 light cut is a fractional product of full range JP8 prepared by a distillation step. The experimental results demonstrate that dry syngas functions almost as well as H2 in the HDS reaction. Sulfur content of the JP-8 light fraction can be drastically reduced to 5ppm or less from 320ppm with either CoMo/Al2O3 or NiMo/Al2O3 catalysts. The impact of various reaction parameters on S removal efficiency will be presented, including syngas flowrate, syngas to fuel mole ratio, H2 partial pressure, total reaction pressure, and H2S concentration. The effect of steam concentration in the syngas on HDS reaction performance was studied for both CoMo/Al2O3 and NiMo/Al2O3, with the latter catalyst demonstrating significantly better performance.