PENGARUH TEMPERATUR PEMANASAN AWAL DAN KECEPATAN ULIR TERHADAP PEROLEHAN MINYAK BIJI JARAK PAGAR (Jatropha curcas linn) DENGAN METODE PENGEPRESAN BERULIR Effect of Preheating Temperature and Screw Speed on Jatropha (Jatropha curcas linn) Seed Oil Yield using Screw Press Method

Abstract

Jatropha (Jatropha curcas linn) is a shrub whose seeds contain oil with a yield of about 30-40% and contains toxins that can not be in the eating, so that the potential to produce biodiesel. Jatropha oil is a clear liquid, yellow, distinctive smell, no taste and no turbid even if stored for long periods. In this study, the oil is obtained by pressing method threaded (screw press). The goal in this research is to study the effect of preheating temperature and screw rotation speed to the yield of Jatropha oil with threaded pressing method. How to screw pressing need pre-treatment consists of the heating process. Jatropha seeds are cleaned of feces and then heated with variable temperature 50˚C, 70˚C and 90˚C screw speed variable 175 rpm, 200 rpm, 220 rpm. Based on observations made variable 9 to obtain the highest percentage of oil rendemen is 10.11% variable preheating temperature 90˚C and 220 rpm screw speed. Moisture content of jatropha seed oil between 0,2-1,2%.The density jatropha seed oil between 0.896 to 0.912 g / ml. Seed oil viscosity distance obtained between 17.33 to 19.51 cp, acid number jatropha seed oil gained between 3.03 to 3.9, jatropha seed oil saponification numbers were obtained between 188, 5 to 194.11. Keywords: Biodiesel, Jatropha, Screw pressing, Temperature