Purification of Methyl Ricinoleate on Producing of Cetane Improver

Purification of methyl ricinoleate on a mixture of methyl ester that was derived from castor oil has been conducted. Methyl ricinoleate with high purity is required in the manufacture of additives for improving the cetane number of diesel oil. Purification of methyl ricinoleate was performed by fractional distillation under reduced pressure at 4.5 mmHg. in order to produce of cetane improver, methyl ricinoleate was nitrated with a mixture of HNO3 and acetic anhydride at 11-13 degrees C for 4 hours. Based on the analysis using gas chromatography (GC) was known that purity of methyl ricinoleate can be increased from 87.2% to 99.5%, with a yield of 30.6% (v/v). FTIR. analysis showedthe absorption spectrum at 3440 (1 /cm), which is derived from the vibrations of the -OH (hydroxyl) on the ricinoleate methyl molecules. The results of characterization showed an increase in density of 0.9161 (mg/L) to 0.9171 (mg /L) and the refractive index of 1.4619 to 1.4627. FUR spectra of nitrated methyl ricinoleateshowedan absorption spectrum at 1627 (1/cm), in which indicates a new compound with nitrate group (-NO3).