Pyrolysis kinetic behavior and Py-GC–MS analysis of waste dahlia flowers into renewable fuel and value-added chemicals

Abstract

To explore the bioenergy potential, kinetic and pyrolysis behavior of waste dahlia flowers (DF), model-free methods and Py-GC–MS were used. Kinetic characteristics of DF biomass were estimated by adopting four model-free methods, Kissinger-Akahira-Sunose (KAS), Ozawa-Flynn-Wall (OFW), Friedman, and Distributed Activation Energy (DAEM). Further, functional groups, the presence of mineral matter in DF biomass, and mineral compounds present in the inorganic residue were analyzed using FTIR, EDX, and XRF. Physicochemical analysis results confirmed its bioenergy potential for conversion into renewable fuel and valuable chemicals. The kinetic results of DF biomass showed that activation energy varied with conversion value, and the thermodynamic analysis indicated multiple step pyrolysis. FTIR analysis confirmed the presence of hemicellulose, cellulose, and lignin in biomass. EDX and XRF analysis also revealed the presence of various useful mineral matter, which had a positive effect during pyrolysis. Py-GC–MS results confirmed that at a lower temperature (500 °C), the formation of ester, nitrogen containing compounds and acid were higher, while at higher temperatures (550 °C and 600 °C), the formation of oxygenated compounds were reduced and the production of hydrocarbons and alcohols increased.