Self-catalyzing pyrolysis of olive pomace

Abstract

In this study, catalytic effect of intrinsic inorganics was evaluated by comparing pyrolysis end products obtained from pyrolysis of olive pomace (OP) in three different initial weights (30,100 and 200 g). Pyrolysis of OP with higher weights led to self-catalyzing pyrolysis resulting in approximately 20% bio-oil quantity increment when pyrolyzed OP weight increased from 30 g to 200 g. Additionally, both intrinsic inorganic percentages remained in pyrolysis chars and organic compounds in pyrolysis liquids altered with pyrolyzed OP weights. While the lowest inorganic percentage in chars was found at the pyrolysis of the highest OP weight, the highest belonged to 30 g OP pyrolysis. Moreover, while oxygenated compounds, namely aldehydes and ketones, in pyrolysis bio-oil decreased explicitly at 200 g OP pyrolysis, variety in alkane and alkene compounds enhanced at higher weights OP pyrolysis. Finally, the effects of temperature, heating rate and retention time on pyrolysis products were evaluated. Results showed that liquid products increased at 5 degrees C/min heating rate and decreased at 1 degrees C/min heating rate as pyrolysis temperature increased from 450 to 600 degrees C in the pyrolysis without retention time. However, reverse tendency was observed in liquid product quantities in the case of pyrolysis with retention time. Furthermore, while effect of temperature increment on pyrolysis gas and liquid was mostly opposite to each other in all pyrolysis conditions, bio-chars' quantity irregularly altered as to pyrolysis conditions.