Study On Rice Bran Synthetical Exploitation

In this thesis, the significance of the rice bran oil with high acid value that was employed to produce biodiesel and that of the wax used to produce triacontanol to exploit the resource of rice bran were discussed. After pretreatment, the rice bran oil with high acid value and methanol (MeOH) were used to produce biodiesel and the optimum reaction conditions of esterification and transesterification reaction were probed into. In the present study, rice bran wax was saponificated. The optimum reaction conditions of the saponification above on no phase-transfer catalyst and phase-transfer catalyst were obtained through orthogonal design. Meantime, ultrasonic radicalization were applied to assist these reactions.Rude triacontanol was extracted by organic solvent (mixture of ethanol and acetone) and the optimum reaction conditions of extraction were acquired.During the experimental course of biodiesel acquirement, rice bran oil should be taken off phosphatides, colloid, wax and water in turn. High moisture content in rice bran oil could arouse deactivation of catalyst and induce the speed of reaction fallen down. Colloid could increase the viscosity of the oil and affect the appearance of biodiesel if the temperature fell. Through orthogonal experiment setup, the optimum reaction conditions of esterification and transesterification were attained, respectively. That is, molar ratio of oil to methanol was 13.75: 1, catalysts 5.52% (oil weight), reaction temperature 65℃and reaction time 3h; molar ratio of methanol to oil was 6: 1, catalysts 1% (oil weight), reaction temperature 55℃-65℃and reaction time 90min, respectively. In the end, conversion efficiency of biodiesel in this method was over 99.3%. In another study (the study on the wax used to produce triacontanol), the digital-and-constant-temperature magnetic stirring apparatus was applied to the main reaction—saponification. The optimum reaction conditions of saponification the on no phase-transfer catalyst and phase-transfer catalyst were gained by orthogonal experiment and both conditions were also compared subsequently. Through ultrasonic radialization assisted with phase-transfer catalyst, the optimum reaction conditions of saponification were obtained that catalyst was 0.5 g, ultrasonic-radialized time 30 min, saponification-reaction time 3h and NaOH 9g. The saponification value of oil reactant was 0.53 mg KOH/g oil. After desiccation, the reaction products were extracted by the mixture of ethanol and acetone. This optimum conditions of extraction were also attained that reactant was 20 g, reaction time 24 h and organic solvent volume (the ratio of ethanol and acetone was 1:1) 200mL. Finally, the rude triacontanol was refined by the method of organic solvent crystallization. In the end, the pure product (triacontanol) was acquired by experimental method (100% purity).In conclusion, that the rice bran oil with high acid value was employed to produce biodiesel has high value for keeping economic sustaining development, obtaining substitute of energy source, reducing environmental pollution and protecting environment in the end. As a kind of growth hormones in plants, the rice bran wax can be applied to produce triacontanol which can enhance the crop product, increase the earning of farmers and reduce the pollution of pesticide. In addition, policosanol refined from rice bran wax was also a resistant for fatigue.