The ethyl acetate and hexane extracted oils are comparable in quantity and quality. The total amount of oil extracted from each was not calculated, as it was a comparative test based on a sample, with ethyl acetate extracting 1.9 g per 10 mL, and hexane extracting 2 g per 10 mL. The Optical Density (OD) test also revealed the comparability of ethyl acetate and hexane as solvents, as the OD of Jatropha ethyl acetate is 0.277 at 600 nm and the OD of Jatropha hexane is 0.254 at 600nm. These results are due to the similar ends of the chemical structure of hexane and ethyl acetate (see diagrams above). These compounds begin and end with the sequence CH3; therefore, they are non-polar compounds. The non-polar ends of ethyl acetate are what make the results of jatropha oil extraction comparable to hexane as a solvent.

                                                                Ethanol

Ethanol: http://commons.wikimedia.org/wiki/File:Ethanol-structure.png

Ethanol, however, is not acceptable as an alternative to hexane, as it was very difficult to remove from the oil once the extraction experiment was complete. Ethanol has a polar (right side of the above diagram) and non-polar end (left side). The non-polar end extracts jatropha oil, but the polar end enables it to extract other organic compounds, resulting in highly impure oil and making filtration very difficult. The final amount of oil after evaporation of the solvent, and possibly some oil that was still dissolved within, was 0.5 g per 10 mL sample. Jatropha ethanol had a tendency to foam during pipetting, indicating dissolved impurities, and results from the OD test of Jatropha ethanol also show many impurities in the oil, as the OD number is 0.693 at 600nm, twice that of either Jatropha ethyl acetate or Jatropha hexane.