Analysis of thermal degradation of peach palm (Bactris gasipaes Kunth) seed using isoconversional models

Abstract

This study aimed to evaluate the pyrolysis of peach palm seed (Bactris gasipaes (Kunth)) of the Amazon region via thermogravimetric analysis under heating rates of 5, 10, 20, 30 and 40 K min−1. The model-free methods of Flynn–Wall–Ozawa (FWO), Kissinger–Akahira–Sunose (KAS), Starink and Vyazovkin were used to predict the kinetic parameters. The gas evolution (TG-MS) was also determined for this biomass. The peach palm kernel showed proximate analysis values and chemical composition similar to those of other lignocellulosic biomasses and an HHV value of 16.5 MJ kg−1. The region of greatest mass loss, i.e., the active pyrolysis, was 169–422 °C. The mean activation energies, calculated by the linear methods FWO, KAS and Starink, were 155.00, 153.22 and 153.61 kJ mol−1, and when calculated by the Vyazovkin method, it was 153.5 kJ mol−1. The reaction model determined by the Criado method confirmed that the pyrolysis of this biomass is complex and crosses several reaction models at α > 0.5. In addition, the main gas products that evolved during active pyrolysis were H2O, CO2, CO, aldehydes, esters, carboxylic acids, and saturated and unsaturated hydrocarbons. From these results, we are able to provide the scientific community with data on the energy potential of Amazonian peach palm seeds, which can be converted into energy via thermochemical processes.