Fluidized bed flash pyrolysis experiments have been conducted on a sample of jatropha oil cake to determine particularly the effects of particle size, pyrolysis temperature and nitrogen gas flow rate on the pyrolysis yields. The particle size, nitrogen gas flow rate and temperature of jatropha oil cake were varied from 0.3 to 1.18 mm, 1.25 to 2.4 m(3)/h and 350 to 550 degrees C. The maximum oil yield of 64.25 wt% was obtained at a nitrogen gas flow rate of 1.75 m(3)/h, particle size of 0.7-1.0 mm and pyrolysis temperature of 500 degrees C. The calorific value of pyrolysis oil was found to be 19.66 MJ/kg. The pyrolysis gas can be used as a gaseous fuel. (C) 2010 Elsevier Ltd. All rights reserved.