Study On The Application Of Auxiliaries In The Separation And Purification Of Eucalyptus Oil

Eucalyptus oil is a kind of fragrant essential oils from natural plants. It’s important component,1,8-cineole, has a good antibacterial, anti-inflammatory, anti-oxidation, local anesthesia, anticorrosive and mosquitoes repel effect. So it is widely used in medicine, food, daily chemical and other fields.Eucalyptus oil resource of China is very rich, so China is the main exporter of eucalyptus oil in the world trade. However, most of our eucalyptus oil for export includes about80%1,8-cineole. This can’t meet the increasing quantity of high-purity of1,8-cineole(purity>99%) in the eucalyptus oil market. So it is of much practical significance to improve the process to get high-purify1,8-cineole product.The research content of this paper:1. Binary vapour/liquid equilibrium(VLE) of1,8-cineole and α-pinene or p-cymene at50mbar were tested. At the same time, T-x-y figures show the boiling temperature range of1,8-cineole and α-pinene or p-cymene are66.5-82℃and81-85℃. So it is more difficult to separate1,8-cineole and p-cymene.2. The use of COSMO therm in eucalyptus oil system has been tried, including the calculation of VLE and the solubility.3. The effect of C2-C4alcohols to the VLE of1,8-cineole and α-pinene was discussed. Comparing the data to the data without assistant agents, adding alcohols is benefit to the separation of1,8-cineole and α-pinene. But when the adding quantity is about2.3%, their effect is almost the same. This result shows that the position of hydroxies has little difference to this system.4. The effect of ionic liquids to the VLE of1,8-cineole and p-cymene was explored. The VLE data of1,8-cineole and p-cymene with three ionic liquids were tested separately. They are [Bmim]Cl,[Bmim]BF4,[Emim] BF4and [P6.4,4,4]Br. The results show that adding ionic liquids has little use. The reason may be that their solubility in1,8-cineole and p-cymene is too low.4. The effect of ionic liquids to distillation was investigated. Choose two ionic liquids ([Emim]BF4and [P6.4,4.4]Br) and increase the adding quality to1%to do distillation experiment. The results show that [Emim]BF4has no obvious effect to the separation but [P6.4,4.4]Br can raise the content of1,8-cineole of the sample in the top. When different quantities of [P6,4.4,4]Br were added, the results show the best quantity is1.2%in setting condition. That is to say, the adding quantity of ionic liquid is not the more the better. The distillation experiments show that the optional pressure is50mbar within the range of study.