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The thermal degradation behaviour and kinetic parameter of non-catalytic and catalytic pyrolysis of rice husk (RH) using rice hull ash (RHA) as catalyst were investigated using thermogravimetric analysis at four different heating rates of 10, 20, 50 and 100 K/min. Four different iso conversional kinetic models such as Kissinger, Friedman, Kissinger-Akahira-Sunose (KAS) and Ozawa-Flynn-Wall (OFW) were applied in this study to calculate the activation energy (E A ) and pre-exponential value (A) of the system. The E A of non-catalytic and catalytic pyrolysis was found to be in the range of 152-190 kJ/mol and 146-153 kJ/mol, respectively. The results showed that the catalytic pyrolysis of RH had resulted in a lower E A as compared to non-catalytic pyrolysis of RH and other biomass in literature. Furthermore, the high Gibb's free energy obtained in RH implied that it has the potential to serve as a source of bioenergy production., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The thermogravimetric of sugarcane bagasse pretreated by hot-water has been studied in this paper. Results indicated that residual solid pretreatment by hot water could decrease the activation energy of phase 2 (270-350 °C) obviously, which makes the pyrolysis more energy-saving. By hot water pretreatment, the hemicellulose, especially xylose (9.78%/o.d. dry mass at 170 °C and 1 h) was greatly extracted into hydrolyzates liquor. Greatly minimized hemicellulose waste at low temperature during pyrolysis also agreed with biorefinery concept. Therefore, bagasse with hot-water pretreatment should be a good pyrolysis material for value-added material., (Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.)

The effects of 1-hydroxybenzotriazole (HBT) and the natural laccase mediators gallic acid, caffeic acid and p-hydroxybenzoic acid, on the enzymatic bleaching of flax pulp were compared. The treatment was performed under atmospheric air and oxygen pressure, and, for the first time, monitored by thermogravimetric analysis (TGA) for comparison with chemical analysis, FTIR and X-ray diffraction (XRD) spectroscopies. Thermogravimetric data were simulated by applying a nucleation kinetic equation to a combustion model based on four pseudo-components (hemicellulose, amorphous and crystalline cellulose, and lignin). The results thus obtained show that the effects of the natural mediators are similar to those of HBT and lead to increased order in cellulose microfibril surfaces. An increase in pulp crystallinity was additionally exposed by the XRD and FTIR techniques, and a reduction in microfibril equatorial size by the XRD patterns. Simulated DTG curves were used to determine the kinetic parameters for thermal degradation., (Copyright © 2011 Elsevier Ltd. All rights reserved.)