US2484979A - Method of modifying glyceride oils - Google Patents

Description

Patented Oct. 18, 1949 METHOD OF MODIFYING GLYCERIDE OILS George Barsky, New York, N. Y., assignor to E. F. Drew & Co. Inc., New York, N. Y., a corporation of Delaware No Drawing. Continuation 01' application Serial No. 426,850, January 15, 1942. This application March 11, 1948, Serial No. 14,399

21 Claims. 1

The present invention is directed to the treat-.

eride oils, which is now abandoned.

In my prior Patent No. 2,182,332 dated December 5, 1939, I have described a method of treating such oils to remove certain of the fatty acids contained therein, and to substitute for the same, other fatty acids, usually having a higher number of carbon atoms. The present invention is directed to similar subject matter in that the oils are treated to remove a portion of the fatty acid content.

In accordance with the present invention, I use a reagent to assist in the reaction whereby certain of the glycerides are decomposed, and the acids freed thereby are distilled. The reagent which I have found to be most suitable for the purpose is boric acid, which is introduced into the oil in relatively small amounts to facilitate the reaction. The boric acid probably acts as a catalyst although it may during the reaction combine in some manner with the oil, the combination being broken down and the boric acid regenerated. Other catalysts having similar properties in the present reaction may be used, such catalysts being generally oxides of metals and the boric acid may for the present purpose also be considered as an oxide of the metal boron. The method is particularly suitable for the treatment of the cocoanut type or group of oil containing substantial amounts of non-hydroxylated lower fatty acids of 6 to 10 carbon atoms which may, in large part, be liberated or be displaced by higher fatty acids.

This type of oil is defined in Dictionary of Applied Chemistry by Thorpe, vol. 2 (1921) page 312, as follows:

Coco-nut oil group.-Under this heading is grouped a number of vegetable fats which differ from all other vegetable fats by having high saponification values in conjunction with high Reichert-Meissl values. The considerable separation of volatile fatty acids which the fats belonging to this group contain, brings them into relationship with the milk fats of mammals.

They differ essentially from the latter, however, in that they do not contain any butyric acid. The high proportions of volatile fatty acids contained in the members of these groups differentiates them from other fats which are also characterized by high saponification values, but do not contain volatile acids.

The fats belonging to the coco-nut oil group are the following: (a) Muriti fat, from Mauritz'a oim'fera (Mart) Acrocomia vinifera (Oerst); (b) mocaya oil, from A. scherocarpa (Mart); Cocos sclerocarpa, C. aculeata (Jacq.); Bactrz's minor (Gert); (c) cohune oil, from Attalea. cohune (Mart); (d) maripa fat, from Palma (Attalea) maripa. (AubL); (e) aouara-kernel oil, from Astrocarpum vulgare (Mart); (f) palm-nut oil, from the kernels of Eloeis guineensis (Linn; Jacq.); (g) coco-nut oil from Cocos nucifera (Linn) and Cocus butyracea (Linn); (h) fat from Cocos acrocomoides.

The following examples will illustrate the nature of the reactions involved and the products obtained:

Example 1 203 parts by weight of refined hydrogenated cocoanut oil are used. Approximately two-thirds of this was put in a kettle and heated to 260 C. with agitation in an atmosphere of carbon dioxide. At that temperature the remaining onethird of the oil, mixed with 12 parts of boric acid, was added continuously over a period of 2 hours. about 150 C., a vacuum was applied, and the free fatty acids then distilled out, the temperature being allowed to rise up to 280 C. at 5 mm., the volatile material being collected by means of a condenser. The residual oil was then allowed to cool, was removed from the kettle, washed Example 2 160 parts of refined hydrogenated cocoanut oil, 2 parts of boric acid, and 50 parts stearic acid were heated in the kettle to 260 C. and kept at that temperature for 2 hours. The mixture Was allowed to cool to about C., vacuum was applied and the free fatty acids then distilled out, the temperature gradually being allowed to rise The mixture was then allowed to cool to.

' up to 280 C..at mm.,

ing collected by means of a condenser. The residual oil was allowed to cool, was removed from the kettle, washed with a small amount of warm water, and then refined with alkali by the procedure common'in the vegetable oil .industry. The distillate was washed and'dried 37 parts of distillate were obtained. This had an acid number of 277 and a saponification number of 286. The residual fat had a saponification number of 234 and a melting point range of 30- 43 C.

Example 3 203 parts of refined unhydrogenated cocoanut oil and 12 parts of'boric acid were used. The procedure was the same as that used in Example 1.

13.5 parts of distillate were obtained. This had an acid number of 313 and a saponification number of 321. The residual oil had a'saponification number of 247.

Example 4 The same quantities of materials were used as in Example 3. The only difference was that the boric acid-cocoanut oil mixture was added to the reaction kettle under vacuum, and after all had been added distillation was continued until the temperature reached 280 C. Y

19.5 parts of distillate were obtained. This had an acid number of 180 and a saponiflcation number of 289. The residual oil had a saponification number of 246.

Example 5 203 parts of refined soya bean oil and 12 parts of boric acid were used. The procedure was the same as that used in Example 1.

4.5 parts of distillate were obtained. This he an acid number of 209 and an iodine number of 48. The iodine number of the residual oil was 129' and of the original oil 134.

Example 6 Example 7 200 parts refined linseed oil and 12 parts of boric acid were used. The procedure was the same as that used in Example 1.

15 parts of distillate were obtained. This had an acid number of 187, a saponification number of 197, and an iodinenumber of 152. The residual oil had a saponiflcation number of 191, an acetyl value of 15.1 and an iodine number of 136. The iodine number of the original oil was 175.

Example 8 40,000 parts of cocoanut oil are mixed with 14,400 parts of palm oil fatty acids and 180 parts of boric acid were placed in a reaction vessel. Heat was applied while maintaining a vacuum and continual agitation, the temperature gradually rising to about 260 C. Vapors of acids were refluxed back to the vessel until the f.f.a. number in the reflux was over 130. The reaction mixture was then steam distilled, slowly at first, until the f.f.a. in the vessel was about 4.

About 44,500 parts of ester were produced and over 9,000 parts of free fatty acids were recovthe volatile material be-.

. 4 ered. The fatty acids consisted essentially of a mixture of caprylic, capric and lauric acids.

Example 9 ,400 parts of cocoanut oil were mixed with 290 parts of boric acid. The mixture was agitated, a partial vacuum of 10" was applied, and heated slowly while refluxing the vapors back into the kettle. After about two hours the vacuum was increased to 23"-27". The temperature was raised to about 290 C. in,about 5 hours total time of heating; it was maintained at about this temperature for an additional 8 hours when the reaction was completed. The product was steam distilled to remove free fatty acids.

About 7,000 parts of ester and over 2,300 parts of distilled lower fatty acids were produced. The refined ester had a setting point of 23.4 C. and an acetyl value of 26.8.

While the reaction is carried out in a single step, it is probable that it takes place in two stages. In the first stage there is most likely a combination of the boric acid with-the fatty material, the nature of the compounds formed being as yet undetermined. In the second stage, during the distillation, there is most likely a splitting up of the combination with a'release of the boric acid together with free fatty acid, the latter being volatilized and the boric acid remaining in the residual ester.

Various products may be formed in accordance with the present invention. Such products may be refined so as togive a composition suitable for edible purposes. The boric acid which is used in the process is washed out during the refining op erations and the other steps of reflningmre those normally used for edible oils and fats.

As a result of a process in accordance with Example 1, for instance, a residual oil or fat is obtained which has an excess of hydroxyl groups and contains at least in part, monoand di-glycerides. Such compositions may be used directly for food purposes or may be reacted as desired. for example with fatty acids, in order to give a fully esterified product.

The physical and chemical characteristics of the oils may be modified at will by the present treatment. For instance, if it is desired to convert a liquid oil into a harder fat, one may by the present process, remove some of the lower fatty acids and introduce higher solid fatty acids in place thereof. Products of this kind may be used in cocoa butter substitutes or for shortening compositions. It is also possible by the treatment of drying oils or of oils containing highly unsaturated fatty acids, to obtain products suitable for use in drying varnishes. Such products may also be reacted, for example, with phthalic anhydride to give resins having improved drying properties.

The amount of boric acid used may vary considerably. In some cases from 0.2% to 1.0-2.0% may be used as in Example 8, or larger amounts up to about 6% as in Example 9. Other variations may be made in the details of the operation in accordance with established practice.

I claim:

1. A method of treating non-hydroxylated mixed glyceride non-drying oils to change the chemical composition thereof which comprises adding to said oil a relatively small amount of boric acid, heating the mixture for a sumcient length of time at a sufliciently high temperature to liberate free fatty acids from the oil, distilling said acids from said mixture and substantially freeing the residue from combined boric acid.

2. A method which comprises adding to an oil of the cocoanut oil group a relatively small amount of boric acid, heating the mixture for a sufncient length of time at a sufficiently high temperature to liberate free fatty acids from the oil, distilling said acids from said mixture. and substantially freeing the residue from combined boric acid.

3. A method of treating non-hydroxylated mixed glyceride oils having higher and lower fatty acids to change the chemical composition thereof which comprises adding to said oil higher fatty acid and a relatively small amount of boric acid, heating the mixture for a sufficient length of time to liberate free fatty acids from the oil, distilling said acids from said mixture.

4. A method of treating non-hydroxylated mixed glyceride non-drying oils to change the chemical composition thereof which comprises adding to said oil a relatively small amount of boric acid, heating the mixture for a sufficient length of time at a sufficiently high temperature to liberate free fatty acids from the oil, distilling said acids from said mixture and washing the residual oil and substantially freeing the residu from combined boric acid.

5. A method of treating non-hydroxylated mixed glyceride non-drying oils to change the chemical composition thereof which comprises adding to said oil a relatively small amount of boric acid, heating the mixture for a suflicient length of time at a sufllciently high temperature to liberate free fatty acids from the oil, removing said acids from said mixture by subjecting the mixture to distillation and substantially free ing the residue from combined boric acid.

6. A method of treating non-hydroxylated mixed glyceride non-dryin oils to change the chemical composition thereof which comprises adding to said oil a relatively small amount of boric acid, heating the mixture for a sufllcient length of time at a sufficiently high temperature to liberate free fatty acids from the oil, removing said acids from said mixture by subjecting the mixture to distillation in the presence of a vacuum and substantially freeing the residue from combined boric acid.

7. A method of treating non-hydroxylated mixed glyceride oils having higher and lower fatty acids to change the chemical composition thereof which comprises adding to said oil a relatively small amount of boric acid, heating the mixture for a suificient length of time to liberate free fatty acids from the oil, adding a higher fatty acid thereto at elevated temperatures to cause a reaction whereby said higher acid is combined with the oil molecule, and distilling said freed acids from said mixture.

8. A method which comprises adding to an oil of the cocoanut oil group a relatively small amount of boric acid, said oil being non-hydroxylated, heating the mixture for a sufficient length of time at a sufficiently high temperature to liberate from the mixed glycerides at least part of the lower fatty acids contained therein, distilling said acids from said mixture, and substantially freeing the residue from combined boric acid.

9. A method of treating non-hydroxylated mixed glyceride non-drying oils to change the chemical composition thereof which comprises adding to said oil a relatively small amount of boric acid, heating the mixture for a sufficient length of time at a sufficiently high temperature to liberate from the mixed glycerides at least part of the lower fatty acids contained therein, distilling said acids from said mixture and substantially freeing the residue from combined boric acid.

10. A method of treating non-hydroxylated mixed glyceride oils having higher and lower fatty acids to change the chemical composition thereof which comprises adding to said oil a substantial amount of free higher fatty acids and a relatively small amount of boric acid, heating the mixture for a suflicient length of time to liberate free fatty acids from the oil and to replace the same by the added acids, and removing said freed acids from said mixture by subjecting the mixture to distillation in a vacuum.

11. A method of treating non-hydroxylated mixed glyceride oils to change the chemical composition thereof which comprises adding to said oil a relatively small amount of boric acid, heating the mixture for a sufficient length of time at a temperature of about 250-325 C. to liberate free fatty acids from the oil, distilling said acids from'said mixture, and substantially freeing the residue from combined boric acid.

12. A method of treating non-hydroxylated mixed glyceride oils to change the chemical composition thereof which comprises adding to said oil a relatively small amount of boric acid, heating the mixture for a sufficient length of time at a temperature of about 250-320 C., removing freed acids by vacuum distillation beginning at about C. and continuing until a temperature of about 250-300 C. has been reached and substantially freeing the residue from combined boric acid.

13. A method which comprises adding to cocoanut oil less than about 6% of boric acid, heating the mixture in a vacuum for at least several hours with gradually increasing temperature to about 275-300 C. and steam distilling the liberated fatty acids, and substantially freeing the residue from combined boric acid.

14. A method which comprises adding to cocoanut oil a minor proportion of palm oil fatty acids and from 0.2% to 1.0% of boric acid, heating the mixture in a vacuum for several hours to about 260 C. and distilling the liberated fatty acids.

15. A method of treating non-hydroxylated mixed glyceride oils to change the chemical composition thereof which comprises heating said 011 to a reaction temperature, adding thereto nonhydroxylated mixed glyceride oil containing a relatively small amount of boric acid, heating the mixture for a suflicient length of time at a sufficiently high temperature to liberate free fatty acids from the oil, distilling said fatty acids from said mixture, and substantially freeing the residue from combined boric acid.

, 16. A method of treating non-hydroxylated mixed glyceride oils taken from the class consisting of the cocoanut oil group, to change the chemical composition thereof which comprises heating said oil to a reaction temperature, adding thereto non-hydroxylated mixed glyceride oil containing a relatively small amount of boric acid, heating the mixture for a suflicient length of time at a sufliciently high temperature to liberate free fatty acids from the oil, distilling said fatty acids from said mixture and substantially freeing the residue from combined boric acid.

17. A method of treating the cocoanut type of oil containing substantial amounts of non-hydroxylated lower fatty acids of 6 to 10 carbon atoms, to change the chemical composition thereof which comprises adding to said oil higher fatty acid and a relatively small amount of boric acid,

assure 7 heating the mixture for a sufficient length of time to liberate free fatty acids from the oil, and distilling said acids from said mixture.

18. A method of treating cocoanut oil to change the chemical composition thereof, which comprises adding to said oil higher fatty acid and a relatively small amount of boric acid, heating the mixture for a suflicient length of time to liberate free fatty acids from the oil, and distilling said acids from said mixture.

19. A method of treating babassu oil to change the chemical composition thereof, which comprises adding to said oil higher fatty acid and a relatively small amount of boric acid, heating the mixture for a sumcient length of time to liberate free fatty acids from the oil, and distilling said acids from said mixture.

20. A method of treating oils which are glycerides of fatty acids having higher and lower numbers of carbon atoms to change the chemical composition thereof which comprises adding tosaid all a fatty acid having a higher number of carbon atoms than the lowest fatty acid in said oil and a relatively small amount of boric acid, heating the mixture for a suflicient length of 8 time to liberate free fatty acids from the oil, and distilling said acids from said mixture.

21. A method of treating oils which are glycerides of fatty acids having higher and lower numbers of carbon atoms'to change the chemical REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date FOREIGN PATENTS Country Date Great Britain 1926 Number Colbeth Apr. 7, 1942