JPS5940381B2 - Method for stabilizing basic aluminum lactate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for stabilizing basic aluminum lactate solutions.

Basic aluminum lactate is expected to be used in many fields such as various binders, coating agents, cosmetic raw materials such as antiperspirants, catalysts, and paint vehicles.

This basic aluminum lactate is obtained by reacting a water-soluble aluminum salt such as aluminum chloride, a basic aluminum nitrate aqueous solution with an alkali metal hydroxide, carbonate, bicarbonate, ammonium hydroxide, carbonate, bicarbonate, By dissolving the precipitated alumina hydrate in an appropriate amount of lactic acid, or by blowing carbon dioxide into an alkaline aluminate aqueous solution and dissolving the precipitated alumina hydrate in an appropriate amount of lactic acid, or by dissolving the precipitated alumina hydrate in an appropriate amount of lactic acid. It can be produced by adding a compound that produces water-insoluble sulfate, such as a calcium compound or barium compound, to a mixed aqueous solution of lactic acid or aluminum lactate and removing the precipitate. Aluminum lactate aqueous solution depends on concentration and manufacturing method, but Al2O3/lactic acid (
It was confirmed that there was an extremely unstable region in the range of molar ratio) 0.2 to 0.55. When a basic aluminum lactate solution in such an unstable range is produced, cloudiness or precipitates are formed during storage, which not only reduces the commercial value but also causes loss of functionality. As a result of repeated research to solve these problems, the present inventors discovered that the presence of a small amount of an inorganic acid or an acid salt of an inorganic acid significantly improves storage stability. It is completed. Examples of inorganic acids or acid salts of inorganic acids used in the present invention include phosphoric acid, boric acid, nitric acid, sulfuric acid, hydrochloric acid, and their acidic sodium salts, acidic potassium salts, and acidic ammonium salts. As a method for making an inorganic acid or an acid salt of an inorganic acid exist in a basic aluminum lactate solution, they may be added after producing a basic aluminum lactate solution. Calcium compounds such as calcium hydroxide, calcium carbonate, calcium oxide, etc. are added to a mixed aqueous solution of aluminum lactate to remove sulfate ions as water-soluble sulfates. Alternatively, the desired sulfate ion may be present in the aluminum lactate solution. Any other method may be used. Therefore, the proportion of the inorganic acid or acid salt of the inorganic acid is determined by the basicity of the basic aluminum lactate solution,
Although it varies depending on the concentration, the inorganic acid used, the type of acid salt of the inorganic acid, etc., the Al2O3/acid radical (molar ratio) is approximately 1.5.
A range of 25 to 25 is preferable. That is, when Al2O3/acid radical (molar ratio) exceeds 25, the solution stabilizing effect is not sufficient, and 1.5
If the temperature is lower than that, the characteristics of basic aluminum lactate itself, that is, the reactivity and corrosivity increase due to the increase in acid strength, will occur, and the characteristics will be lost.

The basic aluminum lactate that is the object of the present invention has an Al2O3/lactic acid (molar ratio) of 0.2 to 2.0. Another effect of the present invention is that a basic aluminum lactate solution containing an appropriate amount of an inorganic acid or an acidic inorganic acid salt is dried by an appropriate drying method such as spray drying, vacuum drying, hot air drying, sun drying, freeze drying, etc. , when this is redissolved, the resolubility is improved.

In general, basic aluminum lactate solutions with poor solution stability are difficult to dry into powder, and even those with excellent solution stability have a slow dissolution rate. However, according to the present invention, the solubility and The dissolution rate can be improved.

The present invention will be further explained below with reference to Examples.

In the following, all percentages are by weight unless otherwise specified. Example 1 53 parts of aluminum chloride aqueous solution (C1O.2%) was added to 100 parts by weight of ammonium carbonate aqueous solution (NH32.7%). It was gradually added while stirring to produce an alumina hydrate.

Incidentally, the reaction temperature at this time was about 30°C. The generated alumina hydrate was filtered using a centrifuge, and further washed with water to obtain Al2O3ll. 4%, NH3O. O6%,
An alumina hydrate containing Cl=0.01% was obtained. Next, 100 parts by weight of this alumina hydrate and 36 parts by weight of lactic acid (75%) were reacted at 45 to 50°C to obtain 8.8% Al2O3,
A basic aluminum lactate aqueous solution having an Al2O3/lactic acid (molar ratio) of 0.37 was prepared.

Hydrochloric acid (35 parts) was added to 100 parts of this basic aluminum lactate solution.
%) was mixed and stored at 30° C. for 3 months, but no change was observed in the solution state. On the other hand, a basic aluminum lactate solution to which no hydrochloric acid was added formed a precipitate in two months.

Example 2 Aluminum sulfate solution (Al2O32.6%, SO3/
To 300 parts of Al2O3 (molar ratio) 3.05) was added a sodium aluminate solution (Al2O33.O%Na2O/Al
After adding 500 parts of 2O3 (molar ratio 1.43) and stirring at high speed, the mixture was filtered using a centrifuge.

Further pulp washing was repeated and Al2O3ll. 5%,
SO3l. 8% Na2OO. A 13% alumina hydrate was produced. Next, 100 parts of this alumina hydrate and lactic acid (
75%) at 60-65°C to form Al2O
37.4% Al2O3/lactic acid (molar ratio) 0.24, Al
A basic aluminum lactate aqueous solution having a molar ratio of 2O3/SO3 of 5.0 was produced. This solution was stored at 20°C for 3 months, but no change was observed. Example 3 Aluminum hydroxide (Al2O36O.2%) 1.3k9 obtained by Beyer method, sulfuric acid (95%)
2.37k9 and lactic acid (40%) 5.18k9 were placed in a reaction vessel, heated and reacted at 90 to 95°C, then cooled and maintained at 80°C, to which were added 2.41k9 of calcium carbonate powder and 1.28kg of water. After the addition, the mixture was gradually poured into a bowl, cooled to room temperature, filtered through ▲, and Al2O31O. 4%, Al2O
A basic aluminum lactate solution having a molar ratio of 3/lactic acid (molar ratio) of 0.34 was prepared.

Phosphoric acid (8 parts) was added to 100 parts of this basic aluminum lactate solution.
When 6.5, 4.0, 1.7, and 0.6 parts (5%) were respectively added and stored indoors in a hermetically sealed manner, all were stable for over 4 months. After storage for four months, the basic aluminum lactate solution was left to dry in a dryer set at 100 to 110°C, and the powder obtained was dissolved in water, and all were dissolved extremely well.

The basic aluminum lactate solution without phosphoric acid became cloudy after 5 days, and solidified into a gel after 15 days.

Moreover, the powder obtained by drying this gel-like solidified product at 100 to 110°C was not dissolved in water. Example 4 Aluminum sulfate powder (Al2O3l6%, SO3/Al2O3 (
After mixing 100 parts of molar ratio) 3.28), 50 parts of lactic acid (40%), and 25 parts of water, 54 parts of calcium carbonate was gradually added, and then 18 parts of lactic acid (40%) and 12 parts of water were mixed. After adding and stirring well, it was filtered and Al2O31O. 9%, Al
A basic aluminum lactate solution with a molar ratio of 2O3/lactic acid of 0.52 was prepared.

To 100 parts of this solution, 1 part of sodium dihydrogen phosphate dihydrate
, 4 parts of ammonium hydrogen sulfate and 1.4 parts of ammonium hydrogen sulfate.
All of the compounds to which 1.5% were added were stable at 25°C for more than 3 months. Example 5 Sodium aluminate solution (Na2Ol.O%, Na2
Carbon dioxide gas was blown into O/Al2O3 (molar ratio 1.23) until the solution pH reached 7.4, and the precipitated alumina hydrate was filtered and washed with water to obtain 2.4% Al2O3L, N
a2OO. An alumina hydrate containing 2% O was obtained.

Next, 100 parts of this alumina hydrate and lactic acid (75%)
52 parts of Al2O3 at room temperature, 8.5% of Al2O3, A
A basic aluminum lactate solution having a molar ratio of 12O3/lactic acid of 0.28 was obtained.

Claims (1)

[Claims] 1 An inorganic acid or an acid salt of an inorganic acid is present in a range of Al_2O_3/inorganic acid (molar ratio) of 1.5 to 25 to basic aluminum lactate of Al_2O_3/lactic acid (molar ratio) of 0.2 to 2.0. A method for stabilizing basic aluminum lactate, comprising: