Hydrocracking of biomass-based Fischer-Tropsch paraffin mixtures was studied on Pt/H-Beta and Pt/H-ZSM-5 catalysts in the temperature range of 225 - 350 °C, at 40 bar total pressure, LHSV = 1.0 h-1, and hydrogen to hydrocarbon ratio of 600 Ndm3/dm3. Two waxes having different carbon number distribution were investigated. The yields of gas, gasoline, and middle distillate fractions obtained from C13 - C69 and the C16 - C45 paraffin mixtures were determined. The selectivity of the two catalysts was compared at about the same C21+ conversion that was controlled by selecting the right reaction temperature. The hydrocracking/hydroisomerization activity of the catalysts reflected their Brønsted acidity. Catalyst Pt/H-Beta showed significant hydrocracking/hydroisomerization activity at 225 - 275 °C, whereas similar activity was attained only at 300 - 350 °C using catalyst Pt/H-ZSM-5. The higher reaction temperature increased the gas yield on expense of the yield of gasoline and middle distillates. Due to shape selectivity substantially less branched chain hydrocarbon product was formed over the Pt/H-ZSM-5 than over the Pt/H-Beta catalyst.
ASJC Scopus subject areas
- Chemical Engineering(all)