Co-pyrolysis of poly (lactic acid) and sugar cane bagasse: Kinetic and thermodynamic studies

For the purpose of investigating the effect of biomass on pyrolysis degradation of plastic wastes, poly (lactic acid) (PLA) has thus been attempted in present work to study the influence of sugar cane bagasse (SCB) on its pyrolysis behaviors and kinetic paramerizations. PLA/SCB samples after prepared by using a suspension blending method have been co-pyrolyzed in nitrogen by non-isothermal thermogravimetric analysis. After adding SCB biomass, the initial pyrolysis degradation temperatures and melting point of PLA are found to have declined substantially. Using pyrolysis results, activation energies of Ea are isoconversionally calculated by applying differential Friedman, integral Kissinger-Akahira-Sunose, Flynn-Wall-Ozawa, Starink and Vyazovkin-Dollimore methods, resulting in 113.7 - 141.7, 101.3 - 140.4 and 79.8 - 210.1 kJ/mol for the PLA blends with 10, 20 and 30 mass % of SCB, respectively. Two approaches based on the Friedman differential equation along with integral methods are attempted for determining pre-exponential factor lnA and pyrolysis reaction model f(alpha). With these modeled results, the experimental curves are matched successfully. Moreover, thermodynamic parameters including Delta H, Delta G, and Delta S values were calculated for the entire pyrolysis process of three blends. The findings acquired from present study are of significance for advancing the design of any relevant pyrolysis reactor for PLA/biomass wastes.