Thermogravimetric Analysis−Fourier Transform Infrared Analysis of Palm Oil Waste Pyrolysis

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.