Abstract

Biodiesel as a plant-derived fuel can be sustainably produced domestically and globally. Botswana has a wide range of oil bearing plants that can be found in the wild. The plants cover all districts of the country. Ochna pulchra is one of the available oil bearing plant and well distributed in the entire country. A large population of mature plant was located in Kweneng District. The local people were engaged to collect the seeds for oil extraction. Ochna spp. extracted oil was a black, smelly oil and biodiesel is with light brown with out discernible odour. The seeds produce about 45% with a high content of free fatty acids (10%). Production of biodiesel from this plant oil involves two-step processes (esterification and transesterification). It was found that, the physico-chemical properties of produced biodiesel were within the established international standards; density was 887kg/m³ versus 860-900kg/m³ ASTMD 1298. The flash point was 153°C versus 120°C minimum ASTMD93 and the energy content was 38.64kJ while the established standard is 42kJ. Ochna pulchra has a great potential to serve as feedstock for biodiesel production because its diesel is desirable or comparable to fossil diesel.