To better understand biomass pyrolysis, the different roles of the three components (hemicellulose, cellulose, and lignin) in pyrolysis are investigated in depth using a thermogravimetric analyzer (TGA). The pyrolysis characteristics of the three components are first analyzed, and the process of biomass pyrolysis is divided into four ranges according to the temperatures specified by individual components. Second, synthesized biomass samples containing two or three of the biomass components are developed on the basis of a simplex-lattice approach. The pyrolysis of the synthesized samples indicates negligible interaction among the three components and a linear relationship occurring between the weight loss and proportion of hemicellulose (or cellulose) and residues at the specified temperature ranges. Finally, two sets of multiple linear-regression equations are established for predicting the component proportions in a biomass and the weight loss of a biomass during pyrolysis in TGA, respectively. The results of the calculations for the synthesized samples are consistent with the experimental measurements. Furthermore, to validate the computation approach, TGA experimental analysis of the three components of palm oil wastes, a local representative biomass sample, is conducted.

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The purpose of this study is to determine the pyrolysis characteristics and gas product properties of palm oil wastes, to promote a general idea of converting the wastes to an energy source. The palm oil waste contains ∼50 wt % carbon, 7 wt % hydrogen, and a trace amount of ash. The low heat value (LHV) of these wastes is ∼20 MJ/kg. They are ideal energy sources for biofuel generation. Thermal analysis demonstrates that these wastes are easily decomposed, with most of their weight lost from 220 °C to 340 °C at slow heating rates. The pyrolysis process could be divided into four stages:  moisture evaporation, hemicellulose decomposition, cellulose decomposition, and lignin degradation. The kinetic analysis showed that the reaction order for the pyrolysis of palm oil wastes and three model biomass components (hemicellulose, cellulose, and lignin) is 1. The activation energy of the palm oil wastes is ∼60 kJ/mol. The decomposition process is prolonged and the maximum mass loss rate is decreased when the heating rate is increased from 0.1 °C/min to 100 °C/min. Varying the particle size from 250 μm to >2 mm has no significant influence on pyrolysis. The main gaseous products from the pyrolysis of palm oil waste are identified using thermogravimetric analysis−Fourier transform infrared (TGA−FTIR) spectroscopy, and, particularly, their real-time evolution characteristics are investigated. This fundamental study provides a basic insight of the palm oil waste pyrolysis, which can benefit our current work in developing an advanced thermal processes for high-yield biofuel production from palm oil waste.