JP2001072610A - Mild removal of residual solvent form perfume and flavor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain mild removal of the solvent residue from organic reaction products sensitive to water or heat, for example, perfume or flavor. SOLUTION: In the purification of an organic reaction product including the residual aromatic solvents, an ester or an ester mixture boiling at a lower temperature than those of the reaction product and the residual solvent is added to the reaction product, then the ester or a mixture thereof is distilled off. The reaction product boils in the range of from 150 deg.C to 400 deg.C, while the residual solvent in the range of from 80 deg.C to 120 deg.C and the ester in the range of from 50 deg.C to 80 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an organic reaction product,
For example, it relates to a method for the gentle removal of solvent residues, in particular toluene and / or benzene, from fragrances and / or flavors.

[0002]

In order to remove solvent residues, such as traces of benzene or toluene, from organic reaction products, such as aromas and / or flavors, an azeotrope is formed with the solvent and the aroma or flavor is removed. Water is preferably used, which entrains them during the distillation from A. Hahn,
Betriebs- und verfahrenst
echnische Groundoperatione
n [Basic Technical and Open
rating Operations], VCH-Ve
rlag, Weinheim, 1990, p. 233).
However, this method cannot be used with water or heat sensitive materials. Because the substance can degrade,
And in the case of aroma and / or flavor, sensory properties may be impaired.

[0003]

A method for purifying an organic reaction product containing an aromatic solvent residue, comprising the steps of: converting an ester or ester mixture having a boiling point lower than the boiling point of the reaction product and the solvent residue into a reaction product; And then distilling off, wherein the reaction product has a boiling point in the range from 150 to 400 ° C. and the solvent residue is from 80 to 1
It has a boiling point in the range of 20 ° C. and the ester is 50 to 8
With a boiling point in the range of 0 ° C.].

Despite being known not to form an azeotrope with toluene (boiling point: 111 ° C.) or benzene (boiling point: 80 ° C.) (azeotropic data III, L. Ho
rsley, American Chemical S
ociety, Washington DC. C. 197
3) It is surprising that ethyl acetate (boiling point: 77 ° C.) and / or methyl acetate (boiling point: 57 ° C.) can remove trace amounts of toluene and benzene from the aroma or flavor.

The method of the present invention can be used widely. It is especially recommended to remove solvent residues from water or heat sensitive substances. In particular, it is preferably used to remove solvent residues from aroma and / or flavor.

In a preferred embodiment of the process according to the invention, a reaction product having a boiling point in the range from 150 to 400 ° C., a solvent residue having a boiling point in the range from 80 to 120 ° C. and a residue in the range from 50 to 80 ° C. Esters having a boiling point are used.

Suitable organic reaction products for the process according to the invention are, for example, alcohols, aldehydes, esters, ketones, lactones, acetals, ketals, ethers and nitriles.

[0008] By use of the process of the present invention, organic solvent residues, such as benzene and toluene residues, are usually removed from the organic reaction product.

For the use of the process according to the invention, the solvent residue is generally between 10,000 and 50 ppm, preferably between 1,0 and 50 ppm.
It is present in an amount from 00 to 100 ppm.

The esters of the process according to the invention are in particular lower alcohols (C ₁ to C ₆ ) and lower alkyl carboxylic acids (C ₁ -C ₆ ).
To C ₆ ) esters. Methyl acetate and ethyl acetate are particularly preferred.

[0011] Mixtures of esters can also be used.

The choice of the ester depends on the problem of separation.
The esters or mixtures thereof are chosen such that their boiling points are lower than the boiling points of the reaction products and the solvent residues.

The use of the process according to the invention makes it possible to separate low-boiling multicomponent mixtures.

According to the process of the invention, from 0.1 to 200% by weight, preferably 10% by weight, of the ester are added to the solvent-containing organic reaction product and then distilled off again. During this distillation operation, solvent residues are removed from the liquid phase product.

[0015] Distillative s
In the case of separation, a rectification column is required.

US Pat. No. 5,458,741 describes extractive distillation for the removal of benzene from cyclohexene or cyclohexane mixtures. 30 different compounds suitable for this extractive distillation are described. These are dimethylsulfoxide, dimethoxymethane, methoxypropanol, furfural, phenol and esters such as ethyl acetate. This purification requires a rectification column, with benzene being obtained at the top and a mixture of ethyl acetate and cyclohexane being obtained at the bottom. In contrast, traces of benzene and toluene are advantageously separated by the process according to the invention.

The use of the esters ethyl acetate and / or methyl acetate offers the following advantages in the purification of aroma and / or flavor. 1. Ethyl acetate and / or methyl acetate are generally inert to flavor and flavor components, which means that no chemical and sensory damage occurs. 2. Ethyl acetate and / or methyl acetate are identical to those found in nature (nature-identity).
cal), which means that trace residues that may remain are acceptable, even in flavor. 3. Ethyl acetate and / or methyl acetate have a low boiling point, thus avoiding imposing high temperatures on the product during the purification process. 4. Removal of solvent residues (benzene, toluene) can be performed with a simple apparatus. No rectification tower is required.

[0018]

EXAMPLE 1 Purification of trans-2-octen-4-ol

[0019]

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4794 g of trans-2-octene-4
-All (98% purity; toluene content: 300 ppm)
And 600 g of ethyl acetate were mixed.

Under reduced pressure increased from 1013 to 10 mbar, a total of 619 g of ethyl acetate was _added to _Tliq.phase :
85-87 ° C and T _{top prod} : distilled off at 50-65 ° C. An additional 600 g of ethyl acetate was then added and distilled off in a similar manner. Trans-2- remaining in the liquid phase
The octen-4-ol product contained <1 ppm of toluene.

Example 2 Purification of phenylacetaldehyde

[0023]

Embedded image

895 g of crude phenylacetaldehyde (GC purity 90%; benzene content: 100 ppm) and 40 g of ethyl acetate were mixed.

Under reduced pressure, increased from 1013 to 10 mbar, a total of 75 g of a mixture of ethyl acetate and low-boiling components was _Tliq.phase : 70-100 ° C. and T _{top prod} :
Distilled off at 76-80 ° C.

The product remaining in the liquid phase contained <10 ppm of benzene.

Example 3 8α, 12-Oxide-13,1
4,15,16-tetranorlabdane
labdane)

[0028]

Embedded image

600 g of 8α, 12-oxide-13,1
4,15,16-tetranorlabdane (purity 68%; toluene content: 800 ppm) and 60 g of ethyl acetate were mixed.

Under reduced pressure increased from 1013 to 1 mbar, a total of 60 g of ethyl acetate were _added to T _liq.phase : 85
-95 ° C and T _{top prod} : distilled off at 50 ° C. The mixture was subsequently stirred at 80 ° C. and 1 mbar for a further hour.

8α, 12-oxide-1 remaining in the liquid phase
The 3,14,15,16-tetranorlabdane product is 15
It contained ppm of toluene.

Although the present invention has been described in detail for purposes of illustration as set forth above, such details are merely for that purpose and unless otherwise limited by the following claims. It is to be understood that those skilled in the art can vary in that respect without departing from the spirit and scope of the invention.

The main features and aspects of the present invention are as follows.

1. A method for purifying an organic reaction product containing an aromatic solvent residue, comprising adding an ester or ester mixture having a boiling point lower than the boiling point of the reaction product and the solvent residue to the reaction product, followed by distilling off, and The product has a boiling point in the range of 150 to 400 ° C. and a solvent residue of 8
It has a boiling point in the range of 0 to 120 ° C and the ester has a boiling point of 5
A method characterized by having a boiling point in the range of 0 to 80 ° C.

2. Process according to claim 1, characterized in that the ester is used in an amount of 0.1 to 200% by weight based on the reaction product.

3. 3. The method according to any one of the above items 1 and 2, wherein the reaction product is aroma and / or flavor.

4. 3. The process according to claim 1, wherein ethyl acetate and / or methyl acetate are used as the ester.

5. The method according to any one of the above 1 and 2, wherein the aromatic solvent residue is removed from trans-2-octen-4-ol by purification.

6. 3. The method according to 1 or 2 above, wherein the aromatic solvent residue is removed from phenylacetaldehyde by purification.

7. 8α, 12-oxide-
3. The method according to the above 1 and 2, wherein the aromatic solvent residue is removed from 13,14,15,16-tetranorlabdane.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) C07C 45/82 C07C 45/82 47/228 47/228 (72) Inventor Thomas Taylmann 37603 Holzminden-Bryuda-Grim -Bake 19 (72) Inventor Carsten Schmitt Germany 37627 Renne Schuttold Tolden Dorfashtrath 11

Claims (1)

[Claims] 1. A method for purifying an organic reaction product containing an aromatic solvent residue, comprising adding an ester or an ester mixture having a boiling point lower than the boiling point of the reaction product and the solvent residue to the reaction product, followed by distillation. And the reaction product is 15
A process characterized in that it has a boiling point in the range from 0 to 400 ° C, the solvent residue has a boiling point in the range from 80 to 120 ° C, and the ester has a boiling point in the range from 50 to 80 ° C.