(741g) The Role of Nickel and Molybdenum Catalysts on the Production of Aviation Fuels from Hydropyrolysis of Biomass

In this talk, we will report the roles of Ni and Mo metals doped on HZSM-5 on the production of liquid alkanes from hydropyrolysis of biomass. Such alkanes are important component of transportation fuels, in particular aviation fuels. We propose a catalytic route that relies on three steps: 1) nickel promotes the formation of methane; 2) molybdenum oligomerizes the methane into aromatics, and 3) nickel hydrogenates the resulting aromatics into alkanes (primarily cycloalkanes). We will show evidence for this route in the hydropyrolysis of Arundo donax. The results include evaluation of the effect of Ni, Mo, and the hydrogen atmosphere on process yields.

Ni-HZSM-5 in the hydrogen leads to a low liquid hydrocarbon yields of 1.5 C%, favoring the formation of methane, and effect that intensifies with temperature. Molybdenum on the catalyst (NiMo-HZSM-5) increased the yield of liquid hydrocarbons from 1.5 C% to 7.9 C% at 400°C. We also verified the effects of the catalysts in separated units, with Ni-HZSM-5 in the fluidized bed reactor and NiMo-HZSM-5 in a secondary fixed bed reactor, which led to a high yield of methane (52.0 C%). We concluded the work with experiments in a fixed bed for oligomerization of methane and hydrogenation of resulting aromatics in a fixed bed reactor with NiMo-HZSM-5 in a hydrogen atmosphere. These experiments showed that, at high temperature (400°C), the NiMo-HZSM-5 converted about 68 % of the methane into paraffins. The results of this work provide evidence for the combined effect of Ni and Mo in the sequence 1) methane production; 2) oligomerization of methane, 3) hydrogenation of aromatics, leading to the production of alkanes.