Fractional crystallization and characterization of rice bran wax

Abstract

This study is aimed to purify rice bran wax by the modified TREF with Crystaf technique. Sand was used as a solid support and hexane as a solvent in crystallization step. After crystallization was completed, the fraction in hexane was gently removed. Then, wax was eluted at various temperature i.e., 30, 40 and 50°C, with hexane to obtain four fractioned waxes, respectively. The physical properties of all fractioned waxes were measured, i.e., saponification value, acid value, iodine value and drop melting point. The identification of the possible components in each fractioned wax was performed by FT-IR and GC-MS. The results of FT-IR indicated that all fractioned waxes were ester waxes. The GC-MS data showed the presence of free fatty acid and fatty acid esters in these fractioned waxes. Only fractioned wax eluted at 40 °C had acid value in the range of 5.0-5.5 which was better than the others and commercial refined wax. Accordingly, the fractioned wax eluted at 40 °C had high value and can be used in cosmetics and medicine industries.