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Star anise (also known as star anise) of precious economic trees, peel, seed and leaves are distilled volatile fennel oil (also known as anise oil). Chinese star anise exports accounted for more than 80% of the world market, has great economic value. Octagonal anisaldehyde more extensive application: anisaldehyde can be used as a raw material of the synthetic drug, also can be used as pesticides, insecticides additives and biological growth inhibitors and brighteners. The so of star anise prepared anisaldehyde Process resources development and utilization of the octagonal opened up broad prospects. This thesis, star anise raw materials, the use of supercritical CO2 extraction of fennel oil, its components identified by GC-MS, and Gas Chromatography absolute molecular distillation technology before and after purification anethole content, and finally the use of microwave extraction device preparation fennel aldehyde. The main content and the results are as follows: (1) the optimum supercritical CO2 extraction of star anise oil: extraction temperature 45 ℃, extraction pressure 30MPa, extraction time 1.6h, particle size 40 to 60 mesh. Extraction temperature of star anise oil yield very significant impact, have a significant effect on the extraction pressure, extraction time had no significant effect. Three factors affect the relationship between the primary and secondary supercritical CO2 extraction of fennel oil yield: T gt; P gt; t, extraction temperature gt; the extracted pressure of gt; extraction time. Proven proved, choose varieties of Xiangshan No. 1, in the extraction of star anise oil yield up to 13.34% under the optimal conditions. (2) from supercritical CO2 extraction of fennel oil by GC-MS identified 42 kinds of chemical composition, the total relative percentage of 99.88%. One of the most important ingredients for trans-anethole, accounting for 81.02% of the total content of fennel oil. Higher levels of: 1 - (3 - methyl-2 - butenyloxy) -4 - (1-propenyl) - 2.42% benzene, cis-anethole 2.34%, grass Penny brain 2.24% anisaldehyde 2.14% acetone-based fennel ether 2.08%, the α-bergamot ene 1.13%. (3) supercritical CO2 extraction and steam distillation, simultaneous distillation and extraction and organic solvent extraction method: steam distillation extract trans-anethole in the relative content of 70.71%, 66.80% simultaneous distillation and extraction 57.59 percent, organic solvent extraction, supercritical CO2 extraction of 81.02%, far higher than using other methods, and anethole more rich aroma. (4) using molecular distillation technology purified trans-anethole and measured by gas chromatography with a molecular distillation absolute content of trans-anethole increased by 68.15% to 80.02%, the the two molecular distillation trans anethole absolute content increased from 80.02% to 89.58%, from yellow, the color becomes almost colorless, the characteristic aroma of star anise is more rich. (5) Microwave power very significantly affect the yield of the anisaldehyde and the hydrogen peroxide concentration has a significant effect on the the anisaldehyde oil yield, reaction time and reaction temperature on the yield anisaldehyde no significant effect. Microwave reaction of four factors anisaldehyde rate of primary and secondary relationship: the Microwave Power gt; peroxide concentration of hydrogen gt; reaction temperature gt; microwave extraction time. Microwave Extraction the anisaldehyde best process for: microwave power 300W, 25% of the concentration of hydrogen peroxide, the microwave reaction time 25min, reaction temperature 20 ° C, the reduction reaction time 1.5h. Anisaldehyde the yield was 87.81% under the process conditions.
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