Bio-Oil Production from Liquid-Phase Pyrolysis of Giant Leucaena Wood

Abstract

Bio-oil production from giant leucaena wood was performed by liquid-phase pyrolysis in the presence of decane as the solvent. Three different types of catalyst (ZSM-5, NiMo/Al₂O₃ and Pt/Al₂O₃) were evaluated in terms of the bio-oil production yield and quality in an autoclave reactor at a reaction temperature of 350°C and initial hydrogen (H₂) pressure of 1 MPa with decane as the solvent. Although the yield was not significantly affected by the catalyst type, CHN analysis revealed that the NiMo/Al₂O₃ catalysts yielded bio-oil with the lowest oxygen content (10.0 wt. %) in 4.30 wt. % yield so that it was selected as the optimal catalyst. Optimization of the reaction temperature (at 250, 300, 350, and 400°C) and the initial H₂ pressure (at 0.5, 1, 2, and 3 MPa) by sequential univariate analysis revealed that the reaction temperature had the greatest influence on the oil yield and oxygen content, reaching a yield of 8.60 wt. % with the lowest oxygen content of 8.50 % at 400°C. Increasing the initial H₂ pressure diminished only slightly the oil and char yield and decreased the gas yield.