阅读说明：本技术 一种含烟叶精油洗脱液的分离方法 (Separation method of tobacco leaf essential oil containing eluent ) 是由 曾勇 黄平 易松山 杨鸿波 陈德亮 陈孟军 于 2019-12-31 设计创作，主要内容包括：本发明适用于洗脱液分离技术领域,提供了一种含烟叶精油洗脱液的分离方法,该方法包括冷冻含有烟叶精油的洗脱液析出结晶,真空过滤后得到冷冻结晶；融化冷冻结晶,得到冷冻液体,真空低温浓缩冷冻液体,得到精油液体；分子蒸馏精油液体。本发明通过在一定温度下通过冷冻结晶将烟叶精油从洗脱液中结晶析出,然后再通过真空低温浓缩和在特定温度下分子蒸馏分离得到头香精油、清香精油、正甜精油和焦甜精油,达到分离含烟叶精油洗脱液的目的,本发明工艺简单,适用于规模化生产。(The invention is suitable for the technical field of eluent separation, and provides a separation method of an eluent containing tobacco leaf essential oil, which comprises the steps of freezing the eluent containing the tobacco leaf essential oil to separate out crystals, and obtaining the frozen crystals after vacuum filtration; melting and freezing to obtain frozen liquid, and concentrating the frozen liquid at low temperature in vacuum to obtain essential oil liquid; molecular distillation of the essential oil liquid. The tobacco leaf essential oil is crystallized and separated from the eluent by freezing and crystallizing at a certain temperature, and then the first essential oil, the faint scent essential oil, the normal sweet essential oil and the caramel essential oil are obtained by vacuum low-temperature concentration and molecular distillation and separation at a specific temperature, so that the aim of separating the eluent containing the tobacco leaf essential oil is fulfilled.)

1. The separation method of the tobacco leaf essential oil containing eluent is characterized by comprising the following steps:

freezing the eluent containing the tobacco leaf essential oil to separate out crystals, and carrying out vacuum filtration to obtain frozen crystals a, wherein the freezing temperature is reduced from the normal temperature to-15 ℃ within 8 hours, and the temperature is kept for 16-20 hours;

melting the frozen crystals a to obtain frozen liquid b, and concentrating the frozen liquid b at low temperature in vacuum to obtain essential oil liquid c;

molecular distillation of the essential oil liquid c, collecting fractions at 118-122 ℃ to obtain top fragrant essential oil, collecting fractions at 148-152 ℃ to obtain fragrant essential oil, collecting fractions at 176-180 ℃ to obtain normal sweet essential oil, and collecting fractions at 196-200 ℃ to obtain caramel sweet essential oil.

2. The method of claim 1, wherein the vacuum filtration is performed at an operating temperature of < -8 ℃.

3. The method for separating an eluate containing essential oil of tobacco leaves according to claim 1, wherein the vacuum cryoconcentration is performed at a pressure of 0.085Mpa to 0.09Mpa and a temperature of 50 ℃ to 55 ℃.

4. The method for separating an eluate containing tobacco leaf essential oil according to claim 1, wherein the pressure of the molecular distillation is 15Pa to 25 Pa.

5. The method for separating an essential oil eluate containing tobacco leaves according to claim 1, wherein in the step of obtaining the top essential oil and the fragrant essential oil by molecular distillation, a relationship between a flow rate of an input liquid for molecular distillation and an area of the heated plate is 20L/h/m²。

6. The method for separating an eluate containing essential oil of tobacco leaves according to claim 1, wherein in the step of obtaining the normal-sweet essential oil and the caramel essential oil by molecular distillation, the relationship between the flow rate of the input liquid by molecular distillation and the area of the heated plate is 10L/h/m²。

7. The method for separating an eluate containing essential oil of tobacco leaves according to claim 1, further comprising a step of recovering the solvent after obtaining the frozen crystals a by vacuum filtration.

Technical Field

The invention belongs to the technical field of eluent separation, and particularly relates to a separation method of an eluent containing tobacco leaf essential oil.

Background

The tobacco leaf essential oil is volatile and semi-volatile substance extracted from tobacco leaf, and has special smell of tobacco. The content of essential oil in tobacco is very low, about 0.1%, and the content and components of essential oil in tobacco of different varieties, different parts, different modulation types and different regions are also different.

The traditional method for obtaining the tobacco leaf essential oil is to directly use tobacco leaves for steam distillation, but some heat-sensitive volatile components are damaged due to the fact that samples are subjected to azeotropy with water during extraction. An improved method based on a steam distillation method, called a gas co-distillation method, is developed later, and can prevent heat-sensitive components from being damaged, but the method is difficult to control due to the requirement of conditions such as constant gas, ice bath and the like, and is not popularized and used finally.

In addition, a method for extracting tobacco leaves by using an organic solvent and then separating and treating the extract to obtain tobacco leaf essential oil is also provided, but the method has low separation efficiency on the tobacco leaf essential oil.

Disclosure of Invention

The invention provides a separation method of tobacco leaf essential oil containing eluent, and aims to solve the problem of low separation efficiency of the existing separation method.

The invention is realized in such a way that the separation method of the tobacco leaf essential oil containing eluent comprises the following steps:

freezing the eluent containing the tobacco leaf essential oil to separate out crystals, and carrying out vacuum filtration to obtain frozen crystals a, wherein the freezing temperature is reduced from the normal temperature to-15 ℃ within 8 hours, and the temperature is kept for 16-20 hours;

the tobacco leaf essential oil in the eluent containing the tobacco leaf essential oil begins to crystallize at minus 8 ℃ and quickly crystallizes at minus 15 ℃, and experiments prove that the tobacco leaf essential oil has the best crystallization effect under the condition of minus 15 ℃, the crystallization rate is higher, the crystallization speed cannot be obviously improved when the temperature is lower than minus 15 ℃, and the temperature of minus 15 ℃ is the best crystallization temperature in the comprehensive view because more energy is consumed due to the lower temperature.

Melting the frozen crystals a to obtain frozen liquid b, and concentrating the frozen liquid b at low temperature in vacuum to obtain essential oil liquid c;

molecular distillation of the essential oil liquid c, collecting fractions at 118-122 ℃ to obtain top fragrant essential oil, collecting fractions at 148-152 ℃ to obtain fragrant essential oil, collecting fractions at 176-180 ℃ to obtain normal sweet essential oil, and collecting fractions at 196-200 ℃ to obtain caramel sweet essential oil.

After one essential oil is obtained by each distillation, the essential oil is put into the same distillation equipment again for heating distillation to obtain the next essential oil, and 4 distillation equipment can be arranged in series in the specific implementation process to form the whole process flow.

Still further, the operating temperature of the vacuum filtration is < -8 ℃.

During vacuum filtration, the environment temperature and the solid-liquid temperature of filtration are required to be lower than-8 ℃, so that the crystallized tobacco leaf essential oil is prevented from being melted into liquid and recovered along with the solvent, and the yield is reduced.

Furthermore, the pressure of the vacuum low-temperature concentration is 0.085Mpa to 0.09Mpa, and the temperature is 50 ℃ to 55 ℃.

Further, the pressure of the molecular distillation is 15Pa to 25 Pa.

Further, in the step of distilling to obtain the top essential oil and the fragrant essential oil, the relationship between the flow rate of the molecular distillation input liquid and the area of the heated plate is 20L/h/m²。

Further, in the step of distilling to obtain the normal sweet essential oil and the caramel sweet essential oil, the relationship between the flow rate of the molecular distillation input liquid and the area of the heated plate is 10L/h/m²。

Further, the step of recovering the solvent after obtaining the frozen crystals a by vacuum filtration is also included.

The separation method of the tobacco leaf essential oil containing eluent provided by the invention is characterized in that the tobacco leaf essential oil is crystallized and separated from the eluent through freezing crystallization at a certain temperature, and then the first essential oil, the fragrant essential oil, the normal sweet essential oil and the caramel essential oil are obtained through vacuum low-temperature concentration and molecular distillation separation at a specific temperature, so that the purpose of separating the tobacco leaf essential oil containing eluent is achieved.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail by the following examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.