Pyrolysis of low-value waste switchgrass: Physicochemical characterization, kinetic investigation, and online characterization of hot pyrolysis vapours

The present study is dedicated to physicochemical characterization, kinetic, thermal degradation behaviors, and online characterization of vapour products through Py-GC–MS and TGA-FTIR. The feasibility study was attained via proximate, ultimate, fibre analysis, and extractive analysis, whereas Vyazovkin (VM), Ozawa-Flynn-Wall (OFW), Kissinger-Akahira-Sunose (KAS), Coats-Redfern (CR), and Distributed Activation Energy Model (DAEM) were employed for kinetics exploration. The feasibility study showed its tremendous ability to be used as pyrolysis feedstock. TGA-FTIR documented the maximum release of CO₂ (26.22%), carbonyls (25.04%), and hydrocarbons (15.93%). Further, kinetic investigation of SWG documented an increased trend of activation energy against progressive conversion. The apparent average activation energy from KAS, OFW, DAEM, and VM was found to be 126.03, 137.54, 130.33, 134.26 kJ mol⁻¹, respectively. Also, kinetics reaction mechanisms are exposed to the multi-nature of decomposition of biomass. Furthermore, the Py-GC–MS investigation established increased hydrocarbons (6.49–11.54%) and reduced oxygen-containing products (24.17–17.27%)