Iso‐conversional kinetic and thermodynamic studies of Indian sagwan sawdust pyrolysis for its bioenergy potential

Abstract

Thermochemical conversion of biomass for bio‐energy production is a potential option where condensable fractions can be utilized as fuel or for valuable chemicals and residual fractions for syngas (CO + H2) production. Present study aims at investigating the physicochemical properties and pyrolysis kinetics of Indian sagwan sawdust degradation using thermogravimetric analyzer at three heating rates (5, 10, and 20 K/min). Physical and chemical properties of ISS were determined by proximate, ultimate, compositional analysis, FTIR, XRD, and higher heating value. TGA results showed maximum devolatilization took place in the temperature range of 480–750 K. Three different iso‐conversional models Flynn–Wall–Ozawa, Kissinger–Akahira–Sunose, and Friedman methods were applied on TGA results to calculate the activation energy and pre‐exponential factors. Average activation energies from FWO, KAS, and Friedman methods were 145.78, 143.35, and 142.87 kJ/mol and pre‐exponential factors ranged from 105 to 1011 indicating empirical first order reaction. Gibbs free energy change and entropy change varied from 184.43 to 187.21 kJ/mol and from −147.21 to −35.59 J/mol, representing disorderness of products were lower than that of the initial compound. The above kinetics, thermodynamics and HHV results, confirmed that ISS has enough potential to be a source bio‐energy. © 2018 American Institute of Chemical Engineers Environ Prog, 38:e13131, 2019

Synthesis and characterization of activated carbon derived fromTectona grandissawdust via green route

“…The significant weight loss began only after 600°C, which revealed the decomposition of undegraded cellulose and lignin in ACTG 60 . The decrease in weight of ACTG after 647.46°C was due to rapid carbonization of the ACTG 9,67 …”

Kinetic and thermodynamic study of pyrolysis of the hydrolyzed residue of rice straw and husk by subcritical water process using thermogravimetric analysis

“…The A increased with increasing SWH temperature for all residues (fresh and hydrolyzed). The lower values of A and E A denote an easier and faster decomposition of biomass at corresponding fractional conversion 59 . These values for fresh RS, fresh RH, HRS, and HRH are comparatively lower and can be treated thermochemically for bioenergy production.…”

“…Gupta and Mondal 59 investigated the physicochemical properties and pyrolysis kinetics of Indian sagwan sawdust degradation at three heating rates (5, 10, and 20°C min −1 ) and using isoconversional models of Flynn–Wall–Ozawa (FWO), Kissinger–Akahira–Sunose (KAS), and Friedman to calculate the activation energy. TG results showed that maximum devolatilization occurred at the temperature range of 207–477°C.…”

“…Gupta and Mondal 59 reported Δ H , Δ G , and Δ S for Indian sagwan sawdust pyrolysis, at a heating rate of 10°C min −1 in an inert atmosphere, varying between 93.91–161.87 kJ mol −1 , 184.43–187.21 kJ mol −1 and −147.21 to −35.59 J mol −1 K −1 . Raza et al 66 reported Δ S for date seeds pyrolysis, at a heating rate of 10°C min −1 in an inert atmosphere, varying between −314 to −38 J mol −1 K −1 .…”

Understanding the pyrolysis kinetics, thermodynamic, and environmental sustainability parameters of Sesamum indicum crop residue

“…The slow pyrolysis process, which operates at a relatively low temperature, heating rate, and high residence time, yields high amounts of solid product (between 40%-60%), whereas fast and flash pyrolysis yields high amounts of liquid product (biooil yield around 50%-80%) due to higher heating rate and very low residence time [10]. The solid by-product produced from pyrolysis is known as biochar which can be used as fertilizers, catalyst development (activated carbon synthesis), wastewater treatment, cosmetics, carbon-nanotubes, and bio-sorbents [11,12].…”