Investigations on co-refining of biomass with vacuum gas oil in the presence of hydro-donor

Abstract

Co-refining process of biomass and vacuum gas oil (VGO) with hydro-donor (tetralin or aromatic enriched fraction of fluid catalytic cracking slurry (FCCRF)) was explored at 320°C for 20min in this work. FCCRF exhibited a much higher capacity for hydrogen donation in accelerating the co-refining process than tetralin. After introducing FCCRF, the maximum yields of co-refining oil and gases (89.51wt.% and 5.43wt.%, respectively), along with the minimum char yield (5.06wt.%) were obtained. The products were analyzed via gas chromatography (GC), gas chromatography-mass spectrometry (GC–MS) and elemental analysis. The results showed that the hydro-donor helped to produce more oxygen-containing compounds (OCCs). The produced OCCs in co-refining oil successfully reduced the viscosity of oil by 60–70%. A co-refining mechanism of VGO and sawdust (represented by hemicellulose) was proposed to explain the co-refining behavior and hydro-donor effect. The elemental equilibrium analysis and Van Krevelen diagram illustrated the industrial feasibility of the sawdust-VGO co-refining process with a hydro-donor.