Pyrolysis of eggplant (Solanum Melongena) stalk agricultural waste

Fast pyrolysis utilizes biomass to produce a product that is used both as an energy source and a feedstock for chemical production. In this study, Eggplant (Solanum Melongena) stalk, a biomass candidate, was investigated as a renewable energy source. Moisture, ash, volatile matter, constant carbon percentage, hemicellulose, cellulose, lignin, extractive matter contents were determined and elementary analysis of the raw material was performed. The thermal decomposition characteristics and kinetics of Eggplant (Solanum Melongena) stalk, an agricultural waste, were investigated. To determine the thermal behaviour of Eggplant (Solanum Melongena) stalk, pyrolysis was performed using a thermogravimetric analyzer (TGA) at different heating rates (2, 3, 5, 7, 10, 12, 15°C/min) at 50mL/min inert nitrogen flow rate. Also, the activation energy was calculated using various degradation models including Friedman (FR), Ozawa-Flynn-Wall (OFW) and Kissinger-Akahira-Sunose (KAS). Pyrolysis experiments were carried out in a 310 stainless steel, fixed bed tubular reactor in an inert gas atmosphere. The effect of pyrolysis parameters such as pyrolysis temperature and inert gas flow rate on the pyrolysis product yields were investigated. A maximum oil yield of 28,16% was optained at a heating rate of 300°C/min, nitrogen gas flow rate of 100cm3/min and pyrolysis temperature of 550°C. The products were characterized by chromatographic and spectroscopic techniques. Furthermore, the liquid product was fractionated by column chromatography and the fractions were further investigated with FTIR spectra and elemental analyses. After characterization of the liquid products obtained from the pyrolysis experiments and their lower fractions, it was determined that these products could be used as liquid fuel and chemical raw material source.