Utilization of Lantana Camara, an invasive and hepatotoxic plant: a kinetic, thermodynamic and experimental studies on its gasification to hydrogen rich producer gas

Gasification gained importance as a biomass conversion technique owing to its versatility and ability to convert a wide range of biomass. It is a potential solution for forest fires and enables energy access to remote hilly areas by converting surplus forest residue into producer gas. In this study, an invasive and toxic Lantana camara (LC) was studied by thermogravimetric analysis (TGA) and downdraft gasification. Higher activation energy, positive Gibbs free energy change, and negative entropy change, as calculated from the TGA data of LC, suggested that its gasification is less easy both kinetically and thermodynamically. Its gasification into hydrogen-rich producer gas was demonstrated in a downdraft gasifier at varying equivalence ratios (ER) from 0.2 to 0.36. Increase in ER increased the temperature of all four zones of the gasifier, and hence, the oxidation of LC in the reacting char zone and endothermic Boudouard and water gas reactions in the inert char zone have increased. Thus, the highest producer gas yield of 2.65 Nm³/kg and carbon conversion efficiency of 57.1% were obtained at the ER of 0.36. But the lower heating value of the producer gas was at the maximum of 5.2 MJ/Nm³ at 0.2 and decreased with an increase in ER to 0.36 due to the higher presence of N₂. The highest cold gas efficiency of 58.2% was obtained at the ER of 0.31. The highest carbon conversion efficiency of 57.1% obtained for LC is lower compared to other biomass, which reaffirmed the difficulty of LC gasification and thus the need for the employment of a catalyst.