Integrated catalytic pyrolysis and catalytic upgrading of Leucaena leucocephala over natural catalysts

Abstract

Catalysts are used to improve the properties of the bio-oil produced through biomass pyrolysis. In this study, natural minerals, such as natural zeolite and dolomite, were used for the catalytic upgrading of the pyrolysis of Leucaena leucocephala. Pyrolysis was performed using an in-house designed fluidized bed system wherein the catalyst beds can be placed in two locations. Dolomite and zeolite catalyst beds were placed in the primary fluidized bed and/or secondary hot filter reactors. Four catalyst configurations were utilized in this study. The effects of the type and location of the catalyst on the catalytic activity and product selectivity were investigated. The highest light bio-oil fraction was obtained using the dolomite catalyst situated at the primary and secondary reactors. On the other hand, the configuration in which the natural zeolite catalyst was placed in the two reactors produced heavy bio-oil that was mainly composed of hydrocarbons. The viscosity, flash point, and fly point of the bio-oil produced in this work fall within the standard values for fuel oils. In particular, the viscosity of the bio-oil produced using the catalysts was lower by 60% of that of the product obtained through noncatalytic biomass pyrolysis. The pyrolysis system employed in this study is a promising technology for catalytic biomass pyrolysis processes.