Variations in oil content and biodiesel yield of Jatropha curcas from different agro-ecological zones of Ghana

2014

English

Jatropha curcas is a perennial, deciduous, shrub, which produces seeds rich in oil that is easily convertible into biodiesel. The major constraint in achieving higher biodiesel yield of J. curcas is insufficient information about its climatic variability. The objective of the current work therefore was to evaluate the oil content and biodiesel yield of J.curcas from different climatic conditions in Ghana. Jatropha seeds were collected from six different agro-ecological zones of Ghana. Oil from each sample was obtained by employing soxhlet extraction using n-hexane. Base-catalyzed transesterification reaction was used to transform the oil into biodiesel. The free fatty acid content and moisture content of the jatropha oil and its biodiesel were determined according to the Association of Official Analytical Chemist method. The seed moisture content ranged from 6.00 to 8.40%, free fatty acid ranged from 2.79 to 4.96% and the oil content ranged from 44.20 to 49.70%. The biodiesel yield ranged from 82 to 90%. The least value was recorded in the Evergreen forest zone whilst the highest value was recorded in the Transition Savanah zone. Climatic condition based on rainfall, seed moisture content and free fatty acid characters studied presented highly negative correlation with biodiesel yield. It can therefore be concluded that in selecting seeds for either biodiesel production or for plantation establishment, selection should be geared towards minimal values for these parameters studied which automatically raise the biodiesel yield in J. curcas seeds. The results of this study could provide the development of active bioenergy enterprise that aim at biodiesel production from J. curcas plant in Ghana.

Derkyi, N. S. A; Sekyere, D.; Oduro, K. A.