Comparative analysis of pyrolysis oils and its subfractions under different atmospheric conditions

Abstract

In this paper comparative analysis of bio-oils and their subtraction from static, sweeping gas and steam pyrolysis of apricot pulp, a food industry waste, was investigated. Experimental studies were conducted in a well-swept fixed-bed reactor with a heating rate of 5 degrees C min(-1), to a final pyrolysis temperature of 550 degrees C. The oil yield which was 22.4% at the static atmosphere reached to the value of 23.2% in the sweeping gas atmosphere by using 100 cm(3) min(-1) N-2 flow rate. The yield of liquid product in steam pyrolysis was higher (27.2%) than the static and inert gas atmosphere. The elemental analyses of the pyrolysis oils were determined, and the chemical compositions of the oils were investigated using chromatographic and spectroscopic techniques. The liquid products were fractionated into pentane solubles and insolubles (asphaltenes). Pentane solubles were then solvent fractionated into pentane, toluene, and methanol subtractions by fractionated column chromatograpy. The aliphatic subtractions of the oils were then analysed by capillary column gas-liquid chromatography and GUMS. For further structural analysis, the pyrolysis oils' aliphatic, aromatic and polar subtractions were conducted using FTIR and H-1 NMR spectra