Medium severity hydrotreating and hydrocracking of Israeli shale oil — II. Testing of novel catalyst systems in a trickle bed reactor

Abstract

Hydrotreating Israeli shale oil at 150 atm, an LHSV of 0.5–1.5 h −1, a temperature of 340–400°C, and a hydrogen to oil ratio of 1500 NL L −1 was studied in a trickle-bed reactor pilot plant packed with two novel catalysts in series. The first catalyst was NiMo supported on wide-pore alumina and the second catalyst was CoMoCr supported on combined zeolite HY-alumina carrier. The desulfurization conversion was higher than 99% over the operating conditions tested while denitrogenation conversion varied over the range 74.3–99.9%. The pseudo-first-order denitrogenation rate constants measured at 380°C increased from 1.9 to 2.9 h −1 with increasing distillation temperatures of shale oil fractions from < 250°C to > 380°C. The apparent activation energy decreased from 29.8 to 23.1 kcal mol −1. The effects of LHSV and temperature on the structure of shale oil components and hydrocarbons distribution was studied using 1 H and 13 C NMR and GC-MS methods. The yields of total liquid product, gasoline, jet and diesel fuels at 380°C and LHSV = 0.5 h −1 were 89.4, 9.3, 22.5 and 65.8 wt% of crude shale oil. The volume yield of liquid product per crude shale oil at those conditions was 106.9%. It contained 160 ppm sulfur and 80 ppm nitrogen. The quality parameters of motor fuels produced from shale oil by hydrotreating with the two-catalyst system meets certain specifications except gasoline, which displayed low Reid vapor pressure and RON 72. A 400 h stability test at 380°C indicated no catalysts deactivation.