JPS6049186B2 - Method for producing magnesium salt of organic sulfonic acid or sulfuric acid ester - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing organic sulfonic acid magnesium salts and sulfuric acid ester magnesium salts useful as detergent bases, particularly liquid detergent bases.

More specifically, the present invention provides stabilized organic sulfonate magnesium salts and sulfate ester magnesium salts that are stabilized so that colloidal impurities do not precipitate over time during use as a component of a liquid composition. This relates to a manufacturing method. Magnesium salts of organic sulfonic acids and sulfuric esters are surfactants with excellent detergency and foaming power, and have recently attracted attention as components of detergents. The method for producing this product is usually a method in which an organic sulfonic acid or sulfuric acid ester is reacted with magnesium hydroxide or magnesium oxide in an aqueous medium.

However, in this method, if magnesium hydroxide or magnesium oxide is of industrial purity,
There is a tendency for colloidal suspended matter to form in the resulting neutralized reaction solution over time. Therefore, when the magnesium salt of an organic sulfonic acid or sulfuric acid ester produced by such a method is used in a cleaning agent, such as a liquid detergent composition, the colloidal suspended matter formed over time will gradually aggregate. , ultimately forming a precipitate, so even if there is no change in its detergency, its commercial value is inevitably reduced significantly.

Removing solid impurities from the neutralized reaction solution immediately after production by filtration or other means also solves this problem.

It is not possible to suppress the occurrence of floating matter and precipitation during storage. In addition, this problem can be solved to some extent by storing the product for a long time to completely precipitate the impurities before use, but this requires a long time and requires special storage equipment. Moreover, there is a problem that the operation is complicated because the colloidal precipitate is filtered. The present inventors have conducted intensive research to overcome the drawbacks of magnesium salts of organic sulfonic acids or sulfuric esters obtained by such conventional methods.
The above-mentioned condition 5 is unique when a product obtained by reacting seawater with milk of lime or milk of dolomite is used as a raw material for magnesium hydroxide i or magnesium oxide, so this is derived from seawater and limestone. We discovered that this phenomenon is caused by impurities such as silica, alumina, and iron oxide, and that this phenomenon can be suppressed by carrying out a neutralization reaction in the presence of certain substances. The present invention has been completed based on this.

That is, the present invention provides stabilization of at least one selected from ethylenediaminetetraacetic acid, nitrilotriacetic acid, tartaric acid, succinic acid, gluconic acid, oxalic acid, their sodium salts, and maleic anhydride in an aqueous medium. The present invention provides a method for producing a magnesium salt of an organic sulfonic acid or sulfuric acid ester, which comprises neutralizing the organic sulfonic acid or sulfuric acid ester with magnesium oxide or magnesium hydroxide in the presence of an agent. The organic sulfonic acids and sulfuric esters used as raw materials in the present invention are generally well known as raw materials for anionic surfactants.

Examples of such substances include linear alkylbenzene sulfonic acid having an alkyl group of 10 to 15 carbon atoms, alkyl sulfate ester having an alkyl group of 8 to 22 carbon atoms, and alkylene oxide having an alkyl group of 8 to 22 carbon atoms. Alkyl ether sulfuric acid ester having an average addition mole number of 1 to 10, alkenyl sulfonic acid having 8 to 22 carbon atoms, and 8 to 2 carbon atoms
2 hydroxyalkanesulfonic acids can be mentioned. In addition, the magnesium oxide and magnesium hydroxide used to neutralize such organic sulfonic acids or sulfuric esters are those that are commercially available as having industrial purity. Let the milk work, then add the water. There are those that form a precipitate of magnesium oxide, which is filtered, washed with water, and dried, or those that are calcined.

This industrial purity product may be further refined to remove impurities, but such a high purity product may be used. When using pure magnesium hydroxide or magnesium oxide, no suspended matter or precipitate is formed, so there is no particular advantage.

Magnesium hydroxide and magnesium oxide used in the present invention contain ferric oxide and alumina of 0.01-0.0% as impurities. % of seeds and 0.01 to 0.1% by weight of acid-insoluble matter. Next, in the present invention, substances added to impart stability to the product include ethylenediaminetetraacetic acid and its sodium salt, nitrilotriacetic acid and its sodium salt, tartaric acid and its sodium salt, and succinic acid and its sodium salt. , gluconic acid and its sodium salt, oxalic acid and its sodium salt, maleic anhydride, etc.

These substances are used in amounts of 0.1 to 2 per 100 parts by weight of magnesium hydroxide or magnesium oxide, calculated as MgO.
It is added at the proportion of the weight. If this amount is less than 0.1% by weight, the effect of imparting stability will be insufficient, and if this amount is less than 0.1% by weight,
Even if a larger amount is used, the stability will not improve and it will be uneconomical. Further, these substances need to be present during the neutralization reaction, and there is no effect even if they are added to the reaction product after the reaction.

The neutralization reaction of the present invention is carried out in an aqueous medium, usually in water, but can also be carried out in a mixture of water and a water-miscible solvent if necessary.

In order to suitably carry out the present invention, the quantitative relationship between water, organic sulfonic acid or sulfuric acid ester, magnesium hydroxide (in terms of MgO), or magnesium oxide should be approximately MgO/H
2O=31200~3no20, stabilizing agent/MgO=
1 ha 000-115. The organic sulfonic acid or sulfuric acid ester and magnesium hydroxide (in terms of MgO) or magnesium oxide are selected in approximately equivalent amounts.

Furthermore, during the reaction, it is preferable to disperse magnesium hydroxide or magnesium oxide in water in advance, and then add the organic sulfonic acid or alkyl sulfate to this. By substantially performing the neutralization reaction in this manner, a reaction solution containing the desired magnesium salt can be formed.

In this case it is advantageous to add a small amount of caustic soda near the end of the reaction in order to complete the neutralization. If this neutralization produces coarse impurities, they are removed by filtration and used as the required base material. In the present invention, when the reaction mixture is allowed to stand still, a lower layer containing a large amount of magnesium salt is separated into an upper layer containing less magnesium salt. A large amount of suspended matter is generated. The neutralized reaction solution obtained by the present invention maintains a clear state without producing colloidal suspended matter even if it is left as it is for a long period of time, so it is suitable as a detergent base.

Next, the present invention will be explained in more detail with reference to Examples.

The magnesium hydroxide used in each example was manufactured from slaked lime milk and seawater, and had a Mg(0H) content of 296.25%.
, R2O3O. 15%, acid insoluble part 0.02%, CaOO
．． 39%, H2OO. Magnesium oxide has a composition of 63% and is a calcined product of this.

Example The neutralizing agent and additives shown in the following table are dispersed in water in the amounts shown, respectively, to prepare an aqueous dispersion having a concentration of 30% in terms of Mg(0H)2.

Next, two amounts of the organic sulfonic acid or sulfuric ester shown in the following table were added to this aqueous dispersion, and a neutralization reaction was carried out at a temperature of 40 to 50°C. Ta. The amount of organic sulfonic acid or sulfuric acid ester used in this case was selected to be slightly in excess of the amount of magnesium compound contained. When the pH of the liquid was stabilized on the acidic side of 2 to 4 by this slightly excessive amount of organic sulfonic acid or sulfuric ester, a small amount of 1N aqueous sodium hydroxide solution was added to the reaction mixture to adjust the pH to 7 to 8. The time required during this period was approximately 4 hours from the start of the neutralization reaction. After the reaction mixture thus obtained was left at 40° C. for 3 days, the presence or absence of precipitate formation was visually determined and the turbidity was measured.

This turbidity measurement was performed by adding a mixture of equal amounts of ethanol and ethylene glycol to the neutralization reaction solution, and adjusting the amount of the active agent component in the solution to 2% by volume.
Measure the absorbance at a wavelength of 600 mμ using a W$L glass cell (
(manufactured by Hitachi, Ltd., using a spectrophotometer) and calculated according to the following formula.

Turbidity = -10gτKari000 The results are shown in the table below.

For comparison, when the stabilizing agent was added after neutralization was completed, and when sodium benzoate was used as the additive,
Examples with no additives are also shown.

Claims (1)

[Claims] 1 In an aqueous medium, in the presence of at least one stabilizing agent selected from ethylenediaminetetraacetic acid, nitrilotriacetic acid, tartaric acid, succinic acid, gluconic acid, oxalic acid, their sodium salts, and maleic anhydride, A method for producing a magnesium salt of an organic sulfonic acid or sulfuric acid ester, which comprises neutralizing the organic sulfonic acid or sulfuric acid ester with magnesium oxide or magnesium hydroxide.