Targeted preparation for hydrocarbons through catalytic hydrodeoxygenation of co-pyrolysis bio-oil using bimetal-loaded Nb2O5 catalyst

Abstract

The co-pyrolysis of industrial enzymatic hydrolysis of lignin residue with waste plastic to produce bio-oil can increase resource utilization and reduce pollution. However, the high concentration of oxygenated compounds, particularly phenolic compounds, limits the large-scale application of crude bio-oil. Bimetallic-loaded bifunctional catalysts have been prepared by loading different transition metals and Ru onto Nb2O5. We explored their performances in crude co-pyrolysis bio-oil hydrodeoxygenation (HDO). Compared to other transition metals, the selectivities for aromatic hydrocarbons, phenolic compounds, and other oxygenated compounds in the upgraded oil obtained by the catalytic HDO of Ni and Ru bimetallic-loaded Nb2O5 (Ni-Ru@Nb2O5) was the lowest, whereas the aliphatic hydrocarbons selectivity was the highest. The selectivities for other oxygenated compounds, phenolic compounds, and aromatic hydrocarbons in the upgraded oil decreased as the Ni loading increased, whereas the aliphatic hydrocarbons selectivity increased. Ni-Ru@Nb2O5 catalyzed HDO of crude bio-oil showed a maximum selectivity of 86.30% for hydrocarbons in the upgraded oil at a reaction time of 2h and a reaction temperature of 280 °C. The degree of deoxygenation of upgraded oil reached 68.87% under optimal conditions, and the molar ratio of H-to-C was increased from 1.31 (crude bio-oil) to 2.37 (upgraded oil). Ni-Ru@Nb2O5 is an effective catalyst method for the HDO of crude bio-oil.