Synthetic jet fuel can be produced from non-petroleum feed materials through Fischer–Tropsch synthesis. When olefin oligomerization is used to produce kerosene-range alkenes from light Fischer–Tropsch derived alkenes, the kerosene-range alkenes have to be hydrotreated before they can be used as blend component for synthetic jet fuel. A typical target for hydrotreating is &lt;1 wt% alkenes in the product to reduce the risk of inadequate storage- and thermal stability. The kerosene-range olefins from oligomerization are free of heteroatoms and are therefore an ideal candidate for hydrotreating using an unsulfided base metal catalyst. Surprisingly little work has been published on kerosene-range olefin hydrotreating over unsulfided base-metal catalysts. The objective of this study was to explore the use of an unsulfided Ni/Al2O3 catalyst for alkene-to-alkane hydrogenation. Hydrotreating of a model feed mixture containing 30 wt% of linear alkenes (from C10 to C14) in a paraffinic matrix was investigated. It was of interest to determine how the length of the carbon chain affects the hydrogenation of alkenes in the kerosene range. The experiments were conducted continuous flow reactor at temperatures from 80°C to 160°C in hydrogen atmosphere at 2 MPa and a weight hourly space velocity of 1.5 h-1. The hydrogen-to-feed ratio was 500:1 normal m3/m3 liquid feed. The products formed were characterized by gas chromatography and the total degree of unsaturation was determined by bromine number titration. At 80°C the conversion achieved was of 53% for 1-decene and 40% for 1-tetradecene while at 120°C the conversion rose to 80% and 67% for 1-decene and 1-tetradecene, respectively. It was also observed that the catalyst deactivated around 38% after the experiment at 120°C. All the results will be presented and discussed in the context of the integration of such a hydrotreating unit in a refinery design for the production of synthetic jet fuel.

Hydrogenation of kerosene-range alkenes over an alumina-supported nickel catalyst

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.