US2993071A - Purification of salts of detergent amino acids - Google Patents
Purification of salts of detergent amino acids Download PDFInfo
- Publication number
- US2993071A US2993071A US798338A US79833859A US2993071A US 2993071 A US2993071 A US 2993071A US 798338 A US798338 A US 798338A US 79833859 A US79833859 A US 79833859A US 2993071 A US2993071 A US 2993071A
- Authority
- US
- United States
- Prior art keywords
- zwitterion
- detergent
- ethylene dichloride
- salts
- amino acids
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 239000003599 detergent Substances 0.000 title claims description 22
- 150000001413 amino acids Chemical class 0.000 title claims description 19
- 150000003839 salts Chemical class 0.000 title claims description 19
- 238000000746 purification Methods 0.000 title description 3
- WSLDOOZREJYCGB-UHFFFAOYSA-N 1,2-Dichloroethane Chemical compound ClCCCl WSLDOOZREJYCGB-UHFFFAOYSA-N 0.000 claims description 21
- 238000000034 method Methods 0.000 claims description 12
- 239000011734 sodium Substances 0.000 claims description 7
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 claims description 6
- 229910052708 sodium Inorganic materials 0.000 claims description 6
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 claims description 4
- 239000011591 potassium Substances 0.000 claims description 4
- 229910052700 potassium Inorganic materials 0.000 claims description 4
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical class [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 3
- 229910052739 hydrogen Inorganic materials 0.000 claims description 3
- 239000001257 hydrogen Substances 0.000 claims description 3
- 238000000926 separation method Methods 0.000 claims description 3
- WCYWZMWISLQXQU-UHFFFAOYSA-N methyl Chemical class [CH3] WCYWZMWISLQXQU-UHFFFAOYSA-N 0.000 claims 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 claims 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical group [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims 1
- 150000001338 aliphatic hydrocarbons Chemical group 0.000 claims 1
- 239000012071 phase Substances 0.000 description 10
- 239000000203 mixture Substances 0.000 description 8
- 239000002253 acid Substances 0.000 description 7
- 239000000243 solution Substances 0.000 description 7
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 6
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 6
- 150000001412 amines Chemical class 0.000 description 6
- 239000001117 sulphuric acid Substances 0.000 description 6
- 235000011149 sulphuric acid Nutrition 0.000 description 6
- -1 amino acid salts Chemical class 0.000 description 5
- 239000012535 impurity Substances 0.000 description 5
- 239000000047 product Substances 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 4
- 238000005191 phase separation Methods 0.000 description 4
- 125000001931 aliphatic group Chemical group 0.000 description 3
- 239000003513 alkali Substances 0.000 description 3
- 125000004432 carbon atom Chemical group C* 0.000 description 3
- 229910052500 inorganic mineral Inorganic materials 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 125000001160 methoxycarbonyl group Chemical group [H]C([H])([H])OC(*)=O 0.000 description 3
- 239000011707 mineral Substances 0.000 description 3
- 238000003756 stirring Methods 0.000 description 3
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 description 2
- 238000013019 agitation Methods 0.000 description 2
- 239000008346 aqueous phase Substances 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 150000001768 cations Chemical class 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 239000002537 cosmetic Substances 0.000 description 2
- 235000014113 dietary fatty acids Nutrition 0.000 description 2
- 239000000194 fatty acid Substances 0.000 description 2
- 229930195729 fatty acid Natural products 0.000 description 2
- 150000004665 fatty acids Chemical class 0.000 description 2
- 239000012467 final product Substances 0.000 description 2
- 239000012074 organic phase Substances 0.000 description 2
- REQSRTKARPEAIW-TVPGTPATSA-N (Z)-2-(dodecylamino)but-2-enoic acid Chemical compound C(CCCCCCCCCCC)N/C(/C(=O)O)=C\C REQSRTKARPEAIW-TVPGTPATSA-N 0.000 description 1
- WJYAJBDKANFOID-UHFFFAOYSA-N 2-(dodecylamino)propanoic acid Chemical compound CCCCCCCCCCCCNC(C)C(O)=O WJYAJBDKANFOID-UHFFFAOYSA-N 0.000 description 1
- ZAOHKACVOFGZOI-UHFFFAOYSA-N Fominoben hydrochloride Chemical compound [Cl-].ClC=1C=CC=C(NC(=O)C=2C=CC=CC=2)C=1CN(C)CC(=O)[NH+]1CCOCC1 ZAOHKACVOFGZOI-UHFFFAOYSA-N 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 125000005396 acrylic acid ester group Chemical group 0.000 description 1
- 238000005576 amination reaction Methods 0.000 description 1
- 150000003863 ammonium salts Chemical class 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 235000019864 coconut oil Nutrition 0.000 description 1
- 239000003240 coconut oil Substances 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 238000010908 decantation Methods 0.000 description 1
- 239000003925 fat Substances 0.000 description 1
- 235000019197 fats Nutrition 0.000 description 1
- 239000000706 filtrate Substances 0.000 description 1
- 229960004594 fominoben Drugs 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003472 neutralizing effect Effects 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 235000019198 oils Nutrition 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 159000000000 sodium salts Chemical class 0.000 description 1
- 229910052938 sodium sulfate Inorganic materials 0.000 description 1
- 235000011152 sodium sulphate Nutrition 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000006104 solid solution Substances 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 239000003760 tallow Substances 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C229/00—Compounds containing amino and carboxyl groups bound to the same carbon skeleton
- C07C229/02—Compounds containing amino and carboxyl groups bound to the same carbon skeleton having amino and carboxyl groups bound to acyclic carbon atoms of the same carbon skeleton
- C07C229/04—Compounds containing amino and carboxyl groups bound to the same carbon skeleton having amino and carboxyl groups bound to acyclic carbon atoms of the same carbon skeleton the carbon skeleton being acyclic and saturated
- C07C229/06—Compounds containing amino and carboxyl groups bound to the same carbon skeleton having amino and carboxyl groups bound to acyclic carbon atoms of the same carbon skeleton the carbon skeleton being acyclic and saturated having only one amino and one carboxyl group bound to the carbon skeleton
- C07C229/08—Compounds containing amino and carboxyl groups bound to the same carbon skeleton having amino and carboxyl groups bound to acyclic carbon atoms of the same carbon skeleton the carbon skeleton being acyclic and saturated having only one amino and one carboxyl group bound to the carbon skeleton the nitrogen atom of the amino group being further bound to hydrogen atoms
Definitions
- the present invention relates to the purification of salts of certain detergent amino acids and more particularly to the removal from salts of certain detergent amino acids organic color, odor and cloudiness forming impurities.
- the salts of the detergent amino acids to which the present invention is directed are those having the following formula: RNH (CIlR'CH COOMe) in which R is an aliphatic hydrocarbon group containing 8-22 carbon atoms and is derived from a detergent forming fatty acid, R is H or CH Me is a salt forming group, m is 0 or 1, n is l or 2 but 1 when R is CH; and the sum of m and n is 2.
- the present commercial method of preparing these salts of detergent amino acids is by the condensation of a primary fatty amine and an acrylic acid ester as disclosed in the Isbell Patent No. 2,468,012.
- the salt of a detergent amino acid may be purified by neutralizing it with a nonoxidizing acid to form the zwitterion as described in the Andersen Patent No. 2,816,920, adding ethylene dichloride to the zwitterion phase to dissolve the color, cloudiness, and odor-causing impurities, and then removing the ethylene dichloride solution containing these impurities to leave a purified zwitterion which may then be reconstituted to the original salt of a detergent amino acid by addition of suitable alkali.
- the salt of the detergent amino acid is dissolved in suflicient water to form 1030% aqueous solution.
- the solution is then neutralized by means of sulphuric acid to a pH within the range of 3.5-5.5, at which stage a two phase separation occurs.
- the upper phase which contains the zwitterion is then removed and mixed with ethylene dichloride, the mixture is then heated until the zwitterion dissolves.
- the original detergent States Patent 0 Patented July 18, 1961 ice amino acid salt is then formed by reconstitutingthe zwitterion with suitable alkali.
- sulphuric acid is the preferred acid in that it is less expensive, less corrosive, and requires less accurate control
- other known nonoxidizing mineral acids such as hydrochloric and phosphoric may also be used with essentially the same results.
- alkali to be used in the reconstitution step will be determined by the salt desired. For instance a sodium salt is desired, NaOI-I will be used, whereas if a potassium or ammonium salt is desired KOH or NH OH will obviously be used.
- Example 1 One thousand grams of flaked sodium ,8 dodecylaminopropionate (C H NHC H COONa) was dissolved in 4,000 grams of water, sulphuric acid was added to adjust the pH to 3.5 whereupon phase separation occurred. The upper phase contained the zwitterion while the other aqueous phase contained the sodium sulphate. The zWit terion phase was then separated and washed twice with water. To the zwitterion phase was added 2,000 grams of thylene dichloride and the mixture heated until the zwitterion dissolved. The solution was then cooled with stirring to room temperature at which point an ethylene dichloride layer separated out and was decanted.
- the zwitterion layer was washed by stirring with another 2,- 000 grams of ethylene dichloride and decanted.
- the zwitterion phase was then reconstituted with sodium hydroxide to a pH of seven and adjusted to a 40% solid solution.
- the final product was noticeably improved in color and odor over a similar product prepared without an ethylene dichloride treatment.
- the mixture was then cooled to room temperature with stirring whereupon the zwitterion. precipitated.
- the mixture was filtered, and 10 grams of the filtrate evaporated to dryness on a steam cone. A residue of 0.0235 gram or 0.6% color, odor and cloudiness forming impurities was recovered.
- the zwitterion was reconstituted with sodium hydroxide to a pH of 7 and adjusted to a 40% solids solution. The final product was noticeably improved in color and odor over a similar product prepared without the ethylene dichloride treatment.
- Example III The process of Example I is repeated with sodium ,3
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Description
2,993,071 PURIFICATION OF SALTS F DETERGENT AMINO ACIDS Donald L. Andersen, Minneapolis, Minn., assignor to General lVIills, Inc., a corporation of Delaware No Drawing. Filed Mar. 10, 1959, Ser. No. 798,338 5 Claims. (Cl. 260-534) The present invention relates to the purification of salts of certain detergent amino acids and more particularly to the removal from salts of certain detergent amino acids organic color, odor and cloudiness forming impurities.
The salts of the detergent amino acids to which the present invention is directed are those having the following formula: RNH (CIlR'CH COOMe) in which R is an aliphatic hydrocarbon group containing 8-22 carbon atoms and is derived from a detergent forming fatty acid, R is H or CH Me is a salt forming group, m is 0 or 1, n is l or 2 but 1 when R is CH; and the sum of m and n is 2.
The present commercial method of preparing these salts of detergent amino acids is by the condensation of a primary fatty amine and an acrylic acid ester as disclosed in the Isbell Patent No. 2,468,012.
While single primary fatty amines may be used in the preparation of these detergent amino acids, the mixtures of amines obtained by the amination of the fatty acids or selected fraction thereof present in common fats and oils such as tallow, coconut oil and the like are readily available and therefore particularly well suited for this purpose.
The production of detergent amino acid salts suitable for use in the manufacture of cosmetic grade products has heretofore required as a starting material the use of expensive, high quality, distilled amines. The presence of color, odor, and cloudiness forming impurities in the less expensive and more readily available lower quality distilled and undistilled primary fatty amines have made salts of detergent amino acids made with them heretofore less desirable for this use.
It is therefore an object of the present invention to provide a novel process of purifying the salts of detergent amino acids which were made with low quality distilled or undistilled fatty amines so that they may be used in the manufacture of cosmetic grade products.
It is also an object of the present invention to provide a novel process by which impure detergent amino acid salts may be upgraded in quality.
It has now been discovered that the salt of a detergent amino acid may be purified by neutralizing it with a nonoxidizing acid to form the zwitterion as described in the Andersen Patent No. 2,816,920, adding ethylene dichloride to the zwitterion phase to dissolve the color, cloudiness, and odor-causing impurities, and then removing the ethylene dichloride solution containing these impurities to leave a purified zwitterion which may then be reconstituted to the original salt of a detergent amino acid by addition of suitable alkali.
In the preferred practice of the invention, the salt of the detergent amino acid is dissolved in suflicient water to form 1030% aqueous solution. The solution is then neutralized by means of sulphuric acid to a pH within the range of 3.5-5.5, at which stage a two phase separation occurs. The upper phase which contains the zwitterion is then removed and mixed with ethylene dichloride, the mixture is then heated until the zwitterion dissolves. After the solution has cooled to room temperature, a phase separation occurs and the ethylene dichloride layer is decanted. Further washings with ethylene dichloride may be required if a particularly low grade product is being purified. The original detergent States Patent 0 Patented July 18, 1961 ice amino acid salt is then formed by reconstitutingthe zwitterion with suitable alkali.
While sulphuric acid is the preferred acid in that it is less expensive, less corrosive, and requires less accurate control, other known nonoxidizing mineral acids such as hydrochloric and phosphoric may also be used with essentially the same results.
The choice of alkali to be used in the reconstitution step will be determined by the salt desired. For instance a sodium salt is desired, NaOI-I will be used, whereas if a potassium or ammonium salt is desired KOH or NH OH will obviously be used.
The following examples further illustrate the practice of the present invention.
Example 1 One thousand grams of flaked sodium ,8 dodecylaminopropionate (C H NHC H COONa) was dissolved in 4,000 grams of water, sulphuric acid was added to adjust the pH to 3.5 whereupon phase separation occurred. The upper phase contained the zwitterion while the other aqueous phase contained the sodium sulphate. The zWit terion phase was then separated and washed twice with water. To the zwitterion phase was added 2,000 grams of thylene dichloride and the mixture heated until the zwitterion dissolved. The solution was then cooled with stirring to room temperature at which point an ethylene dichloride layer separated out and was decanted. The zwitterion layer was washed by stirring with another 2,- 000 grams of ethylene dichloride and decanted. The zwitterion phase was then reconstituted with sodium hydroxide to a pH of seven and adjusted to a 40% solid solution. The final product was noticeably improved in color and odor over a similar product prepared without an ethylene dichloride treatment.
Example [I To 331 grams of an aqueous solution which contained 100 grams of sodium [3, 3',-dodecylaminobispropionate (C H N(C H COONa) was added 169 grams of water. The mixture was heated to 60 C. and sufficient 35% sulphuric acid (37.3 cc.) was slowly added while continuing agitation to adjust the pH of the mixture to 3.5. Phase separation occurred and upon discontinuing agitation, the organic phase floated to the top of the aqueous phase and the latter was separated by decantation. Then 250 grams of ethylene dichloride were added to the organic phase which was heated to C. to melt the zwitterion; the resulting mixture was then heated to boiling on a steam cone. The mixture was then cooled to room temperature with stirring whereupon the zwitterion. precipitated. The mixture was filtered, and 10 grams of the filtrate evaporated to dryness on a steam cone. A residue of 0.0235 gram or 0.6% color, odor and cloudiness forming impurities was recovered. The zwitterion was reconstituted with sodium hydroxide to a pH of 7 and adjusted to a 40% solids solution. The final product was noticeably improved in color and odor over a similar product prepared without the ethylene dichloride treatment.
Example III The process of Example I is repeated with sodium ,3
dodecylaminocrotonate (CnHn5NHCHCH2-O 0 0 Na) with essentially the same results as Example I.
It is to be understood that the present invention is intended to cover all changes and modifications of the examples of the invention herein chosen for the purpose 3 of illustration, which do not constitute departure from the spirit and scope of the invention.
I claim:
1. The process of purifying the salt of a detergent amino acid of the formula RNH (CHR'CH COOMe) where R is an aliphatic hydrocarbon group containing 8-22 carbon atoms, R is selected from a group consisting of hydrogen and methyl, Me is a cation selected from the class consisting of sodium, potassium, and ammonium ions, m is not greater than 1, n is at least 1 and not more than 2 but 1 when R is methyl and the sum of n and m is 2, which method comprises forming the zwitterion, separating said zwitterion, adding ethylene dichloride to said zwitterion, dissolving the zwitterion in the ethylene dichloride, cooling to cause separation of an ethylene dichloride phase, separating the ethylene dichloride and recovering the zwitterion.
2, The process of claim 1, where the zwitterion is formed by dissolving the salt of the detergent amino acid in water and adding suflicient nonoxidizing mineral acid to adjust the pH to 3.5-5.5.
3. The process of claim 2, where the nonoxidizing acid is sulphuric acid.
4. The process of purifying the salt of the detergent amino acid of the formula RNH (CHRCH COOMe) where R is an aliphatic hydrocarbon group containing from 8-22 carbon atoms, R is selected from a group con sisting of hydrogen and methyl, Me is a cation selected from the class consisting of sodium, potassium, and ammonium ions, m is not greater than 1, n is at least 1 and not more than 2 but 1 when R is methyl and the sum of m and n is 2, which method comprises preparing a solution of the salt of the detergent amino acid, adjusting said solution to a pH within the range of 3.5-5.5 by use of a nonoxidizing mineral acid to form a two phase system, one of which contains the zwitterion of said amino acid, separating the zwitterion-con taining phase, adding ethylene dichloride to said phase, dissolving the zwitterion in the ethylene dichloride, then cooling to cause separation of the zwitterion, separating the ethylene dichloride and finally reconstituting the zzwitterion to a salt of the detergent amino acid.
5. The program of claim 4, where the nonoxidizing acid is sulphuric acid.
References Cited in the file of this patent UNITED STATES PATENTS
Claims (1)
1. THE PROCESS OF PURIFYING THE SALT OF A DETERGENT AMINO ACID OF THE FORMULA RNHM(CHR''CH2COOME)N WHERE R IS AN ALIPHATIC HYDROCARBON GROUP CONTAINING 8-22 CARBON ATOMS, R'' IS SELECTED FROM A GROUP CONSISTING OF HYDROGEN AND METHYL, ME IS A CATION SELECTED FROM THE CLASS CONSISTING OF SODIUM, POTASSIUM, AND AMMONIUM IONS, M IS NOT GREATER THAN 1, N IS AT LEAST 1 AND NOT MORE THAN 2 BUT 1 WHEN R'' IS METHYL AND THE SUM OF N AND M IS 2, WHICH METHOD COMPRISES FORMING THE ZWITTERION, SEPARATING SAID ZWITTERION, ADDING ETHYLENE DICHLORIDE TO SAID ZWITTERION, DISSOLVING THE ZWITTERION IN THE ETHYLENE DICHLORIDE, COOLING TO CAUSE SEPARATION OF AN ETHYLENE DICHLORIDE PHASE, SEPARATING THE ETHYLENE DICHLORIDE AND RECOVERING THE ZWITTERION.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US798338A US2993071A (en) | 1959-03-10 | 1959-03-10 | Purification of salts of detergent amino acids |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US798338A US2993071A (en) | 1959-03-10 | 1959-03-10 | Purification of salts of detergent amino acids |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US2993071A true US2993071A (en) | 1961-07-18 |
Family
ID=25173148
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US798338A Expired - Lifetime US2993071A (en) | 1959-03-10 | 1959-03-10 | Purification of salts of detergent amino acids |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US2993071A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3133816A (en) * | 1960-07-15 | 1964-05-19 | Gen Aniline & Film Corp | Photographic coating formulation |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2811549A (en) * | 1954-02-23 | 1957-10-29 | Gen Mills Inc | Process of preparing high solids beta-alanine detergents |
| US2816920A (en) * | 1955-08-11 | 1957-12-17 | Gen Mills Inc | Production of zwitterion of detergent amino acids |
-
1959
- 1959-03-10 US US798338A patent/US2993071A/en not_active Expired - Lifetime
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2811549A (en) * | 1954-02-23 | 1957-10-29 | Gen Mills Inc | Process of preparing high solids beta-alanine detergents |
| US2816920A (en) * | 1955-08-11 | 1957-12-17 | Gen Mills Inc | Production of zwitterion of detergent amino acids |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3133816A (en) * | 1960-07-15 | 1964-05-19 | Gen Aniline & Film Corp | Photographic coating formulation |
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