Sustainable production of aromatics from bio-oils through combined catalytic upgrading with in situ generated hydrogen

摘要

Pyrolysis liquids or bio-oils from rice husks are selectively converted into aromatics through a combined catalytic process, which includes two sequent steps: reforming and upgrading. Hydrogen from methanol and low-weight molecules in bio-oil is in situ generated in the reforming reactor. Methanol (16 wt% of total bio-oils) is added not only as the hydrogen donor, but also as polar solvent for homogenizing bio-oil and reducing its viscosity. Structured nickel nets are used as both the reforming catalyst and heating grid for gasifying high-boiling-point components of bio-oil. In the upgrading reactor, the combination of Co-Ru-Zr/silica with Pt-ZSM-5 gives the highest yield of aromatics (53.7%) and the lowest coke deposition (7.1%). Hydrogen for deoxygenation is generated from reforming of added methanol and low-weight molecules in bio-oil. Coke formation during fixed-bed upgrading can be significantly suppressed through the combined catalytic process. (C) 2014 Elsevier B.V. All rights reserved.