Catalytic Pyrolysis of Liquorice (Glycyrrhiza Glabra L.) in a Fixed-Bed Reactor: Effects of Pyrolysis Parameters on Product Yields and Character

Abstract

Pyrolysis of liquorice (Glycyrrhiza glabra L.) stalks were performed in a fixed-bed tubular reactor with (ZnO, FeCl3, K2CO3, Al2O3. Na2B4O7 center dot 10H(2)O) and without catalyst at three different temperatures (350, 450,550 degrees C) with a constant heating rate of 40 degrees C/min. The amounts of bio-char, bio-oil and gas produced, as well as the compositions of the resulting bio-oils were determined by GC MS. The effects of pyrolysis parameters on product yields were investigated. The results indicate that both temperature and catalysts effect the conversions of G. glabra L. into solid, liquid and gaseous products. The highest conversion of 74.50% and liquid yield of 34.35% were obtained with Na2B4O7 center dot 10H(2)O catalyst at 550 degrees C temperature when 0.224 > Dp > 0.150mm particle sized samples and 100 mL/min of sweeping gas flow rate were used. Liquid products (bio-oils) obtained at 350 and 550 degrees C were analyzed by elemental analysis and gas chromatography/mass spectrometry (GC MS). 133 and 148 different compounds were identified by GC MS in the bio-oils obtained at 350 and 550 degrees C, respectively. (C) 2014 Elsevier B.V. All rights reserved.