Kinetics and mechanism of desulfurization and denitrogenation of coal-derived liquids

Abstract

The design of the high-pressure liquid-phase microreactor has been completed, and assembly of the reactor system is at least half completed. The analytical techniques available for the analysis of sulfur and nitrogen-containing compounds in multicomponent white oil have been thoroughly reviewed, and a satisfactory analysis scheme has been developed. The scheme is centered around high-temperature gas chromatography with a nitrogen-specific detector for analysis of nitrogen-containing organic compounds and a sulfur-specific detector for sulfur-containing compounds. Samples of deactivated catalyst from the Synthoil pilot plant reactor have been analyzed by scanning electron microscopy and electron microprobe. Catalyst near the front of the reactor is 50 to 70% covered with a crust of ferrous sulfide which appears to be responsible for activity reduction. Smaller amounts of Cu, Si, Al, Zn and Ti were also present. Catalyst samples from near the exit of the reactor are essentially free of ferrous sulfide but have an irregular crust of Si-Al ash which covers 20 to 40% of the surface. A 300-cc autoclave has been purchased and set up for the hydrodenitrogenation studies. A catalyst-oil injection system which allows the catalyst and the nitrogen-containing reactant to be injected into the white oil in the autoclave which is already at reaction conditions has been developed. This avoids the problems associated with the heat-up period. (auth)