RU2637318C1 - Method of extracting essential oils from plant materials - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: method includes grinding and preparation of plant material, extraction of the prepared raw material with the gaseous extractant with subsequent separation of the extractant from oil and water fractions. For extraction, dimethyl ether circulating through the extractor is used, which after separation is returned to the process cycle.

EFFECT: invention allows to simplify the technology of producing essential oils.

6 cl, 3 ex

Description

The invention relates to the production of essential oils and can be used in food and pharmaceutical industries, as well as in medicine and cosmetics.

Known (RU, patent 2199875, publ. 10.03.2003) a method for producing flaxseed oil, including mechanical processing of flaxseed, extraction with a solvent, followed by separation of oil from the extract, and during mechanical processing destroy the seed coat, while not violating the core of flaxseed and Liquid gases are used as a solvent during extraction, and extraction is carried out at a temperature of up to 5 ° C. Oil is extracted from the extract by separating the precipitate from the extract and heating the extract to 30 ° C.

The disadvantage of this method should recognize a narrow scope - only getting linseed oil.

Also known (RU, patent 2046825, publ. 10.27.1995) a method for producing oil from plant materials, including extraction with hexane or other low-boiling hydrocarbon solvents that are not miscible with water, separating the miscella from the defatted residue by filtration or centrifugation and separating the oil from the solvent by evaporation of the latter . Moreover, the plant material is pretreated with a single or multiple aqueous solution of ethanol in such a concentration that the final concentration in the resulting liquid phase is 50-70 vol%, and the solid phase remaining after treatment with ethanol is subjected to extraction with hexane or low boiling hydrocarbon solvents.

The disadvantage of this method can be recognized as its complexity, due to the multi-stage process.

Also known (RU, application 93017053, publ. 12/27/1995) a method for producing oil from plant materials. According to the known method, extraction is carried out with hexane or other low-boiling hydrocarbons that are not miscible with water, the miscella is separated from the fat-free residue by filtration or centrifugation, and the oil is separated from the solvent by evaporation, and before extraction, the plant material is pre-treated once or repeatedly with an aqueous solution of ethanol such that the resulting liquid phase, the final concentration of ethanol was 50-70 vol.%, and the solid phase remaining is extracted with hydrocarbons I am after treatment with ethanol.

The disadvantage of this method can be recognized as its complexity, due to the multi-stage process.

This source of information is accepted as the closest analogue of the developed method.

The technical problem solved by the developed method is to expand the range of methods for the extraction of essential oils.

The technical result achieved by the implementation of the developed method consists in simplifying the technology for producing essential oils.

To achieve the specified technical result, it is proposed to use the developed method for the extraction of vegetable oils from plant materials. According to the developed method, grinding and preparing vegetable raw materials is carried out, the prepared raw materials are extracted with a gaseous or liquefied extractant, followed by separation of the extractant from the oil and water fractions, and dimethyl ether circulating through the extractor is used for extraction, which is returned to the technological cycle after separation.

The developed method is simpler and more technologically advanced than the method used as the closest analogue by reducing the number of technological operations.

The separation of the extractant from the oil and water fractions, as well as the separation of the oil and water fractions can be realized by any known method.

For the implementation of the method, any extractor can be used to ensure the performance of these technological operations.

In a preferred embodiment, the extraction is carried out at a pressure of from 1 to 25 bar and at a temperature of from 5 to 50 ° C.

Mostly they grind plant materials from 0.1 mm to 20 mm, depending on the type of raw material.

Depending on the type of raw material, a single or multiple pressure change is used to increase the access of extractant to all particles of the mass of raw materials.

In some embodiments, the extractor is pre-evacuated to remove air residues and reduce extractant costs.

The developed method is usually implemented as follows.

A portion of the plant material is ground to a size of 0.3-2 cm. The ground portion is placed in a perforated container, which is placed in the extractor. An extractant, dimethyl ether, is fed into the extractor at a pressure of 10 bar and a temperature of 35 ° C. Vegetable oil and the aqueous fraction are completely removed from the plant material with an extractant. Next, the extractant in any known manner is separated from the oil and water fractions and returned after regeneration to the process.

This method does not impose special requirements on the degree of grinding of raw materials, since the extraction conditions create conditions that optimize the process by changing the hydrodynamics of the extraction, ensuring the elimination of stagnant zones, as well as a deeper penetration of the extractant into the intercellular spaces and capillaries of plant materials due to a single process or repeated depressurization.

In the future, the developed method will be illustrated by implementation examples.

Example 1. The black pepper peas, ground up to 0.6 mm, are loaded into the extractor, vacuumized to remove residual air, the pressure in the extractor is equalized to the working level of 2 bar. The extractor serves liquefied DME. Next, DME is supplied to a pressure of 8 bar and flow extraction is carried out — the extractant is circulated for 3 hours. At the end of the circulation, the black pea meal is discharged from the extractor, and the extract from the distiller. The degree of extraction of black pepper essential oil was 85.5%.

Example 2. In the extractor load crushed up to 0.3 mm pulp of allspice. The process is carried out analogously to example 1, for 3 hours. The pressure increase is carried out up to 7 bar, then up to 10 bar. The degree of extraction of allspice essential oil was 96.4%.

Example 3. In the extractor load crushed to 1 mm cardamom. Extraction is carried out by liquefied DME. The process is carried out analogously to example 1. The circulation of the extractant is carried out for 4 hours. The pressure is increased to 10 bar. The degree of extraction of cardamom essential oil was 95.0%.

Claims (6)

1. The method of extraction of essential oils from plant materials, including grinding and preparation of plant materials, extraction of prepared materials with subsequent separation of the extractant from the oil and water fractions, characterized in that for extraction using dimethyl ether circulating through the extractor, which after separation is returned to the production cycle . 2. The method according to p. 1, characterized in that the extraction is carried out at a pressure of from 1 to 25 bar. 3. The method according to p. 1, characterized in that the extraction is carried out at a temperature of from 5 to 50 ° C. 4. The method according to p. 1, characterized in that in the preparation process, the grinding of plant materials from 0.1 to 20 mm, depending on the type of raw material. 5. The method according to p. 1, characterized in that, depending on the type of raw material, a single or multiple change in pressure is used to increase the access of extractant to all particles of the mass of raw materials. 6. The method according to p. 1, characterized in that the preliminary evacuation of the extractor is carried out to remove residual air and reduce extractant costs.