Assessment of Catalytic Materials for Hydrothermal Upgrading of Algae Biocrude

Liquefaction of wet biomass such as algae, crop residues, and biowaste in hot compressed water produces a crude bio-oil while obviating the need to first dry these feedstocks.  This crude bio-oil is viscous, has a high total acid number, and is rich in heteroatoms such as O, N, and S.  Hydrothermal catalytic upgrading of the crude bio-oil may be a pathway to its transformation to a hydrocarbon stream that could be blended with petroleum and refined using existing fuel production infrastructure.  Various catalysts have shown promising activity for upgrading these crude oils, but no catalyst has yet proven to be clearly suitable for long-term operation in these harsh conditions.  This poster will present results from an international collaborative effort that systematically studied the efficacy of a set of different metals supported on different materials.  We will compare various metal catalysts and supports that have shown some resistance to degradation and deactivation in hydrothermal environments.  The catalyst supports include anatase TiO₂, barium hexaaluminates, lanthanum hexaaluminates, and zeolites.  This careful systematic study provides new information about how best to perform hydrothermal catalytic upgrading of crude bio-oils.