US2073054A - Process of producing pure soaps from oxidized nonaromatic hydrocarbons - Google Patents

Description

Patented Mar. 9, 1937 UNITED STATES PATENT OFFICE FROM OXIDIZED DROCARBONS NONAROMATIC HY- Hans Franzen, Mannheim, Germany, assignor to Farbenindustrie Aktiengesellschaft,

Frankfort-on-the-Main, Germany No Drawing. Application October 17, 1934, Serial No. 748,717. In Germany October 19, 1933 4 Claims.

The present invention relates to the production of wetting, washing and dispersing agents.

The soap solutions obtained by the saponification of the oxidation products of hydrocarbons 5 of high molecular weight, as for example of paraffin waxes or mineral oil fractions, cannot be directly worked up into useful wetting, washing and dispersing agents because they are dark in color and have an undesirable odor. It is therefore necessary to subject them. to a very troublesome purification process before their further working up, as for example by precipitating the fatty acids from the soap solutions by means of mineral acids, purifying the fatty acids by distillation and then reconverting them into soaps with alkali. Considerable waste of valuable material, alkali and acid, however, always takes place.

I have now found that very pure soaps (which are directly employable as wetting, washing, dispersing and like agents) are obtained in a simple manner by dissolving oxidation products of,hy-

drocarbons of high molecular weight in a waterinsoluble solvent, treating the solution obtained with an aqueous solution of a water-soluble alkaline-reacting substance (such as caustic,"

alkali, alkali metal carbonate, ammonia. or water-soluble amines), separating the aqueous solution obtained and extracting therefrom the un.-"

saponifiable constituents by means of a waterinsoluble solvent and if desired evaporating the resulting soap solution to dryness. The waterinsoluble solvent to be used for dissolving the oxidation products may be the same as or may be different from that to be used for extracting the non-saponifiable matter from the soap solution separated.

As initial materials may be mentioned for example oxidation products of paraflin waxes, mineral oils or higher boiling fractions thereof as for example petroleum or middle oils, and also the products obtained by the oxidation of destructive hydrogenation products of coals and tars.

Single solvents or mixtures of several solvents may be employed. As water-insoluble solvents or solvent mixtures may be mentioned benzine, benzene, cyclohexane, cyclohexanol, tetrahydronaphthalene, carbon tetrachloride and mixtures of benzine and ethyl alcohol.

The solution of the oxidation products in the water-insoluble'solvents or solvent mixtures may take place at ordinary or elevated temperature. Usually it is effected at temperatures not below 20 C. The upper limit of the temperature used is the boiling point of the solvents employed and it is preferable to work near the latter temperature. The solutions thus obtained are then treated with aqueous solutions of alkali metal hydroxides, alkali metal carbonates, ammonia or. amines, as for example 'methylamine, ethylamine, dimethylamine, mono-, dior triethanolfamine. The amount of the said aqueous solutions depends on the concentration of the said basic substances in the aqueous solutions and on the saponification value of theoxidation products employed. The said basic substances are preferably used in an excess of from about 5 to 10 per cent of the theoretically required amount calculated on the saponification value. The working temperature depends on the composition of the oxidation'products and may be readily ascertained by a simple experiment. It may be desirable to work under pressure in order to avoid losses of solvents, especially if low boiling solvents are employed. After mixing thoroughly, the whole is allowed to settle; the soap solution is then withdr vvn. For the purpose of complete- 'ly removing t eunsaponifiable constituents, the aqueous soap solution is treated with a watersired temperature under ordinary or elevated ,pressure, filtered if necessary and if desired evaporated to dryness in a suitable manner under ordinary or decreased pressure. The drying may be effected for example in a roller dryer or a Krause apparatus.

The products obtained according to this invention are pale soaps which have practically no undesirable odor and are therefore capable of employment for further' Working up into shaped soaps or other washing or like agents.

The following examples will further illustrate the nature of this invention but the invention is not restricted to these examples. The parts are by weight.

Example 1:

Hard paraflin wax is oxidized by blowing with air at from to C. while employing 0.05 per cent of sodium palmitate and 0.05 per cent of manganese palmitate as catalysts for 4 hours in the usual manner. 1200 parts of the resulting oxidation product, having a saponification value of 149, are dissolved in a mixture of 2400 parts of benzine and 600 parts of ethyl alcohol and intimately stirred for half an hour at a temperature of from 56 to 58 C. with a solution of 184 parts of sodium carbonate in 920 parts of water. The mixture is then allowed to settle and the soap insoluble solvent (or solvent mixture) at any desolution. is withdrawn. The latter is extracted with 1200 parts of benzine and evaporated to dryness in a roller dryer. A good yield of a colorless and odorless soap powder having a high wetting, foaming and washing power is'thus obtained.

Example 2 A so-called middle oil is oxidized with air at from about to C. while adding 0.2 per cent of manganese naphthenate as a catalyst for 3 hours, an oxidation product thus being obtained having a saponiflcation value of 90. 630 parts of this oxidation product are dissolved in 1200 parts of benzene and intimately stirred for half an hour at a temperature of from 40 to 45 Cl with a solution of 44 parts of sodium hydroxide in 560 parts of water. The mixture is then allowed to settle, the soap solution is drawn off and extracted with 600 parts of benzene. The soap solution thus obtained may be directly employed for washing. It may also be evaporated to dryness by spraying in a Krause apparatus, a yellowish odorless soap powder having a high foaming and washing power thus being obtained.

Example 3 500 parts of the oxidation product obtained as set forth in the first sentence of Example 1 are dissolved in about 710 parts of diethylether. The solution is stirred together with a solution of 200 parts of triethanolamine in 1000 parts of water with the addition of 240 parts of ethyl alcohol at 33 C. for 45 minutes in a closed vessel. After cooling, the soap layer is separated and extracted once or twice with 710 parts of diethylether. The soap solution thus obtained is a highly active washing agent.

What I claim is:-

1. The process of producing pure soaps from oxidized non-aromatic hydrocarbons of high molecular weight which comprises dissolving the said oxidized hydrocarbons in a water-insoluble solvent, treating the solution obtained with an aqueous solution of a water-soluble alkaline-reacting substance in the presence of a lower aliphatic alcohol, separating the aqueous solution and extracting therefrom the unsaponifiable constituents by means of a water-insoluble solvent.

2. The process of producing pure soaps from oxidized non-aromatic hydrocarbons of high molecularweight which comprises dissolving the said oxidized hydrocarbons in a water-insoluble solvent, treating the solution obtained with an aqueous solution of a water-soluble alkaline-reacting substance in the presence of a lower aliphatic alcohol, separating the aqueous solution, extracting therefrom the unsaponifiable constituents by means of a water-insoluble solvent and evaporating the said aqueous solution to dryness.

3. The process of producing pure soaps from oxidized non-aromatic hydrocarbons of high molecular weight which comprises dissolving the said oxidized hydrocarbons in a mixture of waterinsoluble solvents, treating the solution obtained with an aqueous solution of a water-soluble alkaline-reacting substance in the presence of a lower aliphatic alcohol, separating the aqueous solution and extracting therefrom the unsaponifiable constituents by means of a water-insoluble solvent.

4. The process of producing pure soaps from oxidized non-aromatic hydrocarbons of high molecular weight which comprises dissolving the said oxidized hydrocarbons in a mixture of waterinsoluble solvents, treating the solution obtained with an aqueous solution of a water-soluble alkaline-reacting substance in the presence of a lower aliphatic alcohol, separating-the aqueous solution and extracting therefrom the unsaponiflable constituents by means of a mixture of water-insoluble solvents.

HANS FRANZEN.