Thermal and catalytic pyrolysis of Karanja seed to produce liquid fuel

Abstract

Thermal and catalytic pyrolysis of one non-edible oil seed Karanja was reported in this work. Thermal pyrolysis of Karanja seed was performed in a semi batch reactor at different temperatures in order to find out the optimum temperature (550°C) for utmost liquid yield (55.17%, weight basis). The pyrolytic liquid was separated as oil and aqueous layer with a yield of 33% and 22.17% by weight respectively. The oil was rich in hydrocarbon and thus termed as pyrolytic oil which can be used as fuel. Catalytic pyrolysis was carried out at 550°C with an aim to enhance the yield and physical properties of the pyrolytic oil. Three catalysts such as CaO, Al2O3 and Kaolin were used at various feed to catalytic ratios (2:1, 4:1, 8:1). Catalytic pyrolysis confirmed that lower feed to catalyst ratio (8:1) increased the yield. In terms of pyrolytic oil yield, the catalysts Al2O3 and Kaolin proved to be better than CaO whereas all the catalysts resulted in better quality of pyrolytic oil in comparison with thermal pyrolysis. The yield of oil was 31.28%, 34.49% and 35.17% for CaO, Al2O3 and Kaolin respectively. The composition analysis provided the evidence that the acids produced during thermal pyrolysis of Karanja seed got converted to esters during catalytic pyrolysis which might be the reason for the changed pH and increased calorific value.