Thermal Degradation Kinetics and FT-IR Analysis on the Pyrolysis of Pinus pseudostrobus, Pinus leiophylla and Pinus montezumae as Forest Waste in Western Mexico

José Juan Alvarado Flores,Jorge Víctor Alcaraz Vera,Antonio Alfaro Rosas,Santiago José Guevara Martínez,Francisco Márquez Montesino,Jaime Espino Valencia,María Liliana Ávalos Rodríguez,José Guadalupe Rutiaga Quiñones

doi:10.3390/en13040969

Abstract

For the first time, a study has been carried out on the pyrolysis of wood residues from Pinus pseudostrobus, Pinus leiophylla and Pinus montezumae, from an area in Western México using TGA analysis to determine the main kinetic parameters (Ea and Z) at different heating rates in a N2 atmosphere. The samples were heated from 25 °C to 800 °C with six different heating rates 5–30 °C min−1. The Ea, was calculated using different widely known mathematical models such as Friedman, Flynn-Wall-Ozawa and Kissinger-Akahira-Sunose. The Ea value of 126.58, 123.22 and 112.72 kJ/mol (P. pseudostrobus), 146.15, 143.24 and 132.76 kJ/mol (P. leiophylla) and 148.12, 151.8 and 141.25 kJ/mol (P. montezumae) respectively, was found for each method. A variation in Ea with respect to conversion was observed with the three models used, revealing that pyrolysis of pines progresses through more complex, multi-stage kinetics. FT-IR spectroscopy was conducted to determine the functional groups present in the three species of conifers. This research will allow future decisions to be made, and possibly, to carry out this process in a biomass reactor and therefore the production of H2 for the generation of energy through a fuel cell.

Highlights

Around the world, the amount of publications regarding renewable energies and biofuels accounts for a large percentage of the total of approximately 56% [1,2]
5 of that the values obtained depend on factors such as atmosphere, gas flow, sample mass and heating rate, and on the mathematical treatment of the data. To evaluate such data at different heating rates, this paper describes the pyrolysis process from three isodifferent heating rates, this paper describes the pyrolysis process from three iso-conversional kinetic conversional kinetic models, one differential corresponding to Friedman [26], and two integrals, one models, one differential corresponding to Friedman [26], and two integrals, one from Flynn-Wall-Ozawa from Flynn-Wall-Ozawa (FWO) [36] and the other from Kissinger-Akahira-Sunose (KAS) [28]
With respect to the activation energies, it is worth mentioning the excellent concordance between the results obtained with deviations of less than 10% between the OFW and KAS methods. These results demonstrate that the OFW and KAS methods are highly reliable for predicting activation energy in pyrolysis processes

Summary

Introduction

The amount of publications regarding renewable energies and biofuels accounts for a large percentage of the total of approximately 56% [1,2]. The use of biomass has been required to meet the energy needs. From the 20th century onwards, due to increased energy demand and the excessive use of various fuels, the incorporation of biomass in the fuel mix has been. Energies 2020, 13, 969 seriously considered, especially in developing countries [3]. Biomass is considered one of the main sources of energy, as well as one of the new alternatives that have been implemented to try to reduce the amount of emissions of CO2 , SOx , NOx and particulate matter produced during energy production processes [4]. It is worth mentioning that, in the case of CO2 , the use of oil-based fuels, accounts for more than 70% of human related emissions of this gas worldwide, and the rest is attributed to changes in land use. Pollution in some countries is alarming, as is the case in the United

Methods

Results

Conclusion