DE680183C - Process for bleaching sulfonated oils and fats - Google Patents

Description

Method for bleaching sulfonated oils and fats The invention relates to a method for bleaching sulfonated oils and saving, in particular sulfonated vegetable oils, such as castor oil or olive oil, and sulfonated saving of animal origin, such as tallow. 'Sulphonated oils are used in the textile industry, leather industry, cosmetic industry and other industries. In many of these industries, a light colored sulfonate is necessary and desirable. Unfortunately, however, this is the case with the usual sulfonation, e.g. B. castor oil with concentrated sulfuric acid, the product available is relatively dark in color. Sulphonated olive oil is e.g. B. usually greenish to brownish green colored, while die'Inclustrie, especially for hair washing agents, prefers a lighter colored product. Sulphonated sebum is often very yellow in color and in this case cannot be used with other softening agents for soap of the color we-en.

The task of bleaching sulfonated oils and fats had to take into account that the previously common bleaching with strong bleaching agents and at elevated temperatures and prolonged treatment times, deleterious and corrosive effects on these sulfonated Products.

It has been found that sulfonation products of glycerides of higher fatty acids economically and effectively in a manner known per se with solutions of hydrogen peroxide and substances that supply such, if one can works in the presence of cobalt catalysts.

It is preferable to use the commercially available 300-oil solution of hydrogen peroxide, but it is also possible to use water peroxide solutions of other concentrations. For example, a 15 %, 7.59 or 3% solution can be used, whereby the corresponding amount must be used compared to the 30000 solution.

It is also possible, instead of hydrogen peroxide solutions, to use solder in which water peroxide is formed under the conditions of bleaching. Thus a lustrous metal peroxide or a solution containing aliperoxide such as sodium peroxide and an acid such as sulfuric acid or hydrochloric acid can be used. In the same way , a vain solution - of a persalt, such as alkali percarbonate, all-caliper sulfate, can be used. Hydrogen peroxide, however, is the preferred bleaching agent because glass. it is commercially available in high concentrations, adjustment of the pH value is not necessary and no undesirable residues in the form of compounds or salts are left on decomposition with evolution of active oxygen which causes the bleaching. When using 30% hydrogen peroxide solutions, only a little water is added to the sulfonated product. This is an advantage as otherwise large amounts of water would have to be removed.

Cobalt salts, especially those of high water solubility, such as cobalt chloride, cobalt nitrate, cobalt sulfate and cobalt acetate, are used as cobalt compounds. However, less soluble cobalt compounds such as cobalt oxide and cobalt 2 can also be used, since the presence of only very small amounts of the accelerator or catalyst in the solution is necessary. It was determined, . that amounts of cobalt on the order of i to io parts per million parts of the substance to be bleached give very good results. When using a small amount of cobalt salt, e.g. B. 0.5 parts per million parts of bleached material, the time required for bleaching is longer than with larger amounts of cobalt salt, such as. B. 10 or 15 parts / million.

The cobalt salt is preferred to the sulfonated product to be bleached in the form of a solution, a compound. or a salt in water or another suitable solvent added.

After the cobalt compound has been thoroughly distributed in the sulfonated oil or fat by stirring, the hydrogen peroxide solution is added to the mixture. In general, about 0.5 to 5% of 30% hydrogen peroxide solutions or corresponding amounts of solutions of other concentrations, based on the weight of the sulfonated oil or fat, are used. In the case of relatively smaller quantities, higher temperatures and a longer bleaching time are necessary, while in the case of quantities of more than 5010 bleaching takes place quickly and an elevated temperature is not necessary. In most cases, however, it is preferred to use a lenae of 0.75 to 1.0 0.11.

Although the bleaching effect also occurs at room temperature when using these amounts, it is preferred to work at "temperatures between about 30 and 50". Sulphonated tallow is heated to at least he liquefies himself. At over 50- a darkening of the oil or fat can occur. Therefore it is preferable to avoid temperatures well above this value. For some oils, however, temperatures above 50 ° can be used with good success without the products becoming darker. When relatively large amounts of the accelerator and a relatively high concentration of the peroxide solution are used, bleaching occurs rapidly even at room temperature.

During bleaching, it is advisable to keep the mixture agitated either from time to time or continuously in order to achieve a good distribution of the bleaching agent and the accelerator in the sulfonate; in some cases it may be desirable to stir only at the beginning. The treatment is preferably continued until an analysis of the mixture shows that only a little decomposed hydrogen peroxide is still present. The bleaching is generally complete in less than 24 hours, if elevated temperatures and / or relatively large amounts of bleaching agent and accelerator are used after 5 to 12 hours. Example ii kg of sulfonated castor oil is placed in a 2 liter beaker. 5 cc of a solution of ¢, 769 g-Co SOE # 7 ILS O- in 1 l of water are added to the oil. This amount corresponds to a ratio of 5 parts of cobalt to 1 million parts of bleach. The t_11 and the cobalt sulphate solution are carefully stirred, then 10 g of a 3oo'o solution of water peroxide are added. The mixture is stirred thoroughly and then left to stand at room temperature for about 24 hours. After this time the oil is bleached and has a sufficiently light color. The small amount of cobalt salt is left in the oil as it is not detrimental. If the same batch is heated to 50 ° and this temperature is maintained for approximately 3 hours, the mixture being constantly stirred thoroughly, after this time the oil is bleached and has a sufficiently light color. Example ei kg of sulfonated castor oil are in a 2 l Beclier 3 ccm of a solution of 4.769 g of Co SO i #; 11_O in 1 1 of water was added. This amount corresponds to 3 parts of cobalt to 1 millioil parts of bleaching ut. The cobalt salt and ü1 %% - Earth thoroughly stirred overall to the I3eschleuni-er well in <'ll distribute. Be on it. the sulfonated i ') 1 loo:; added to a 300% hydrogen peroxide solution. The mixture is kept in I3eweun® for about 30 hours. After this time the (il is bleached and has a sufficiently light color. The bleaching effect achieved is somewhat better than after the procedure according to Example I. However, the required treatment time is somewhat longer Solution of .1.76t) g of Co S 0.i # 7 H. O in r 1 of water was added. This amount corresponds to one part of cobalt for every million parts of bleach. The cobalt salt is well distributed in the mixture by stirring. Then -io g of a 300% hydrogen peroxide solution are added and a temperature of 50 ° is maintained. After 24 hours the oil is completely bleached and analyzes show that the peroxide has completely decomposed.

10 g of a sample of the untreated oil are rapidly titrated with a 10% potassium permanganate solution in the presence of 20 cc water and 10 cc zoojoiger sulfuric acid. It takes about 0.35 to 0.5 cc of the permanganate solution to produce a faint pink color in the oil. 10 g of a sample of the already bleached oil are titrated in the same way. If no greater lengths of the normal permanganate solution are required to produce a noticeable color in the bleached oil than is necessary to produce a pale pink color in the sample of the untreated oil, it is assumed that this is the case Water stol peroxide is essentially completely decomposed, and that there is no improvement in the bleaching content if the treatment is continued. Example 4 i kg of sulfonated olive oil will add up to one light yellow coloring with the application of i Where 3oüoiäer hydrogen peroxide solution, which is produced electrolytically, bleached. Before the bleaching, the sulfo- ned olive oil spelled; green colored and had the tendency to have a -greenish- to deposit white precipitate. It %% - earth 3 parts million (o, oo3 g) Ko- holding sulphate in the form of a wiißri, # eil @ i.isllilg des Salt added to your sulfonated oil. Thereon \ t'el '(lell about io ccin 3oo @' pi "e water Oxide solution added. The mixture is stirred and ettva 6 hours to about 50 - held. After this time the product will be bleached 1! 1l (1 has vain enough light color the analysis for free, urine-replaced water substance superoxide by addition. of titanium sulfate it is determined that the peroxide is completely constantly decomposed. If a clock v (111 Titanium sulphate in strong sulfuric saturation (, iller If the amount of u1 is added, a yellow color indicates that decomposed hydrogen peroxide is still present in the mixture. EXAMPLE 5 Two samples of sulfonated tallow, each equal to every one ounce, are bleached with 30000 hydrogen peroxide solution using 3 parts / million (0.0003 g) in the form of cobalt nitrate. In one case 0.50'o (0.5 ccm), in the other case i, oo! O (1.0 ccm) 300,000 hydrogen peroxide solution were used.

Both samples are bleached to a sufficiently bark color. The results with the hydrogen peroxide solution in amounts of i °, 'o are somewhat better than with o, 5 0, 'o.

A temperature of about 50 'is maintained during the bleaching and the samples stirred at intervals of r 5 'minutes. After about 7 hours results in both cases a test by adding a little titanium sulfate solution to one small sample of the mixture that the peroxide is completely decomposed. The bleaching is therefore over after this time.

The process of the invention can be used quite generally in the case of sulfonates of the glycerides of the higher fatty acids. The use of a cobalt compound as an accelerator has the effect that (3) the end product is completely free of decomposed water. If decomposed peroxide were to remain in the sulphonate, the development of oxygen in the decomposition of the products results in Scl111 ' Often times, explosions have occurred as a result of the development of oxygen when a bleached product was stored in a closed high-temperature filter and where the oxygen-evolving compounds remained in the product. The use of cobalt as an accelerator in the bleaching of sulfonated oils and Fats excludes the possibility of harmful storage of coarse sulphonates. If hydrous superoxide without cobalt inhibition is used as an accelerator in the treatment of sulphonated oils and fats, mild periods of time vnil i or \ 1) 11a1011 are required #, the sulfomat completely free of tiiizvrsctztetn 1'erux @ '(1 is.

Claims (1)

1 a T n.:; T .v N sul; i: c: it E : t. Method for the corpse of sulfo- nieren i 11 (.1l and fats, inslies (@ lltlc're v "n stilfoili (#rt ('u 1'llanicn @ ilen, like l ,, izinttsiil ulld tllivcnül, and v (111, tlltollici't ('ili "talg 111i! \ 1-a @ aerst (ilt; ulle @ (@@@ (1, thereby gc- indicates that in the presence of isobalt catalysts, it is expedient to bleach in a ratio of from 1 to 10 parts, preferably from 3 to 5 parts, to one million parts of the substance to be bleached. a. Process according to Claim i, characterized in that solutions of hydrogen peroxide are used in quantities. from 0.5 to 5 percent by weight, preferably 0.5 to 1 percent by weight, based on the material to be bleached, of 3oo'oiger hydrogen peroxide solution. 3. The method according to claim i and characterized in that one bleaches at an elevated temperature, preferably between 30 and 50 ".