JPH0441498A - Production of phosphate - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to an improvement in a method for producing a phosphoric acid ester. More specifically, the present invention relates to a method for producing a highly pure phosphoric acid ester in high yield without using a dehydrohalogenating agent or a solvent.

(Prior art and its problems) Phosphate esters of organic hydroxyl compounds can be used as detergents,
It is widely used as an emulsifier, antistatic agent, textile oil agent, etc., but in these applications, it is usually used as a mixture of phosphoric acid monoester, phosphoric diester, phosphoric triester, or condensed phosphoric ester. ing.

By the way, among these phosphoric acid esters, phosphoric acid diesters and triesters, such as di-2-ethylhexyl phosphoric acid, are used as liquid ion exchangers for scouring of uranium ore, recovery of uranium from wet phosphoric acid, and nickel. It is used for applications such as separation of cobalt or rare earth elements, and recovery of organic metals from waste liquids.

Until now, phosphate esters of organic hydroxyl compounds have been
It is produced by reacting a specific hydroxyl compound with phosphorus oxyhalide, phosphorus pentoxide, polyphosphoric acid, etc., but in such a method, a mixture of phosphoric acid monoesters and diesters is obtained, and a monoester is produced. It is difficult to selectively obtain only one ester.

If high-purity phosphoric esters are required, the product obtained by the above method may be separated by a method such as recrystallization, or phosphoric esters other than the phosphoric esters needed may be hydrolyzed. This is done by removing the particles (Japanese Unexamined Patent Publication No. 13791/1983).

Such a method requires complicated operations and inevitably reduces the yield.

In order to improve the shortcomings of such methods, a method has been proposed in which an organic hydroxyl compound and phosphorus trichloride are reacted, the reaction product is then chlorinated with chlorine, and then hydrolyzed (Japanese Patent Application Laid-Open No. 1983-1993). -103188). Such a method requires a multi-step process and requires complicated reaction operations and reaction equipment.

The present inventors have also discovered a method for obtaining high-purity phosphoric acid ester in high yield by controlling the reaction temperature and dropping method in the reaction between an organic hydroxyl compound and phosphorus oxyhalide (Japanese Patent Application Laid-Open No. 64-1979-1). According to these methods (No. 143880, JP-A-64-143881), highly pure phosphoric esters can be obtained in high yield;
Since it is necessary to use a dehydrohalogenating agent such as an amine, an organic solvent, and an amine salt treatment step after the reaction, there has been a desire for a process for producing phosphate esters at a lower cost and more easily.

(Problem of the Invention) An object of the present invention is to provide a new method that can produce phosphoric acid diester and phosphoric acid triester with high purity and at low cost.

(Means for Solving the Problems) In order to solve the above problems, the present inventors have conducted intensive research and found that when reacting an organic hydroxyl compound with phosphorus oxyhalide, the alkoxy group of phosphorus By changing the reaction temperature stepwise depending on the degree of substitution, the process can be carried out without using dehydrohalogenation agents or solvents.
Discovered that it was possible to synthesize highly pure phosphate esters,
The present invention has now been completed.

That is, according to the present invention, when producing a phosphoric acid ester by reacting phosphorus oxyhalide and an organic hydroxyl compound and then hydrolyzing if necessary, substantially the same equivalent amount of organic hydroxyl to phosphorus oxyhalide is used. The compounds are added and reacted while maintaining the reaction temperature below 15°C, and then substantially the same or twice the equivalent of the same or different organic hydroxyl compound as above is added for 30 minutes.
The present invention provides a method for producing a phosphoric acid ester, which is characterized in that the addition reaction is carried out at a temperature of .degree. C. or higher.

The present invention will be explained in detail below.

The organic hydroxyl compound used in the method of the present invention is an organic compound having a hydroxyl group, such as an unsubstituted or substituted alcohol, an unsubstituted or substituted phenol, or an alkylene oxide adduct thereof, and examples of such compounds include: Ethyl alcohol, propyl alcohol, butyl alcohol, pentyl alcohol, hexyl alcohol 22-ethylhexyl alcohol, heptyl alcohol, octyl alcohol, nonyl alcohol, decyl alcohol, undecyl alcohol, dodecyl alcohol, tridecyl alcohol, tetradecyl alcohol, pentadecyl alcohol, Straight-chain alcohols having 2 to 24 carbon atoms, such as hexadecyl alcohol, heptadecyl alcohol, octadecyl alcohol, oleyl alcohol, eicol alcohol, eicosyl alcohol, isostearyl alcohol, or higher alcohols obtained by the oxo method, Ziegler method, or Guerbet method. Branched saturated or unsaturated alcohols, or their alkylene oxide adducts (p≦50), as well as phenol, alkylphenols such as butylphenol, octylphenol, nonylphenol, dodecylphenol, or their alkyleneoxide adducts (p
≦50).

In the present invention, first, substantially the same equivalent amount of the organic hydroxyl compound is added to phosphorus oxyhalide and allowed to react while maintaining the reaction temperature at 15°C or less, preferably from 0 to 10°C. At a reaction temperature of 15° C. or lower, substantially only the monoesterification reaction proceeds selectively. When the reaction temperature is higher than 15°C, diesterification reaction also occurs,
In addition, a decomposition reaction of phosphorus oxyhalide also occurs, so
The yield and selectivity decrease, and it is not possible to obtain a highly pure phosphoric acid ester.

After the phosphorus oxyhalide is converted to the monoester, substantially the same or twice the equivalent amount of organic hydroxyl compound is added to effect diesterification or triesterification.

Diesterification and triesterification progress more slowly than monoesterification, and the reaction temperature is 30°C or higher, preferably 40°C.
It is necessary to carry out the test at temperatures above ℃. If the reaction temperature is lower than 30° C., the monoester remains unreacted and high purity cannot be obtained.

The organic hydroxyl compound used in the diesterification or triesterification step of the present invention is appropriately selected depending on the structure of the desired phosphate ester, and is the same or different from the organic hydroxyl compound used in the monoesterification reaction. can be used in diesterification and triesterification reactions. In other words, if the desired phosphoric ester is a symmetrical phosphoric ester, the same organic hydroxyl compound used in the monoesterification reaction may be used for the diesterization or triesterification, but if the desired phosphoric ester is asymmetrical, In the case of a phosphoric acid ester, a different organic hydroxyl compound from the one used in the monoesterification reaction can be used in the diesterification and triesterification.

In addition, in this specification, "substantially the same equivalent" as used in relation to the amount of organic hydroxyl compound added means that it does not necessarily have to be the same equivalent in a strict sense; for example, 1 mole of phosphorus oxyhalide When adding the same equivalent amount of organic hydroxyl compound to
It can range from 5 to 1.05 moles. If the amount of the organic hydroxyl compound added deviates from this range, the deviated amount will be produced as a by-product.

In the present invention, hydrogen halide gas is produced as a by-product during the reaction, but in order to make the reaction proceed smoothly, an inert gas such as nitrogen gas is flowed into the reaction vessel, and the hydrogen halide gas is mixed into the reaction vessel. It is also possible to remove it from

The product obtained by the reaction of the present invention is subjected to a hydrolysis treatment by adding a required amount of water. This hydrolysis is usually carried out under reflux conditions. In this way, a solution containing a phosphoric acid ester is obtained. After this hydrolysis treatment, excess water is distilled off,
By further drying as necessary, the desired phosphoric ester can be recovered with high purity.

(Effect of the invention) According to the present invention, high purity and high quality phosphoric acid ester
Without the use of dehydrochlorination agents and solvents.

It can be produced with high yield. According to the invention.

For example, phosphoric acid esters suitable as liquid ion exchangers for extraction and separation of rare earth elements, smelting uranium, recovery of useful metals from waste liquids, etc. can be produced at low cost, and have great industrial significance. be.

(Example) The present invention will be explained in more detail with reference to Examples.
The present invention is not limited in any way by these examples.

Example 1 30.7 g (0.20 mol) of phosphorus oxychloride was placed in a three-neck flask equipped with a thermometer and a stirrer, and while maintaining the temperature at 10°C, 2-ethylhexyl alcohol 2
6.0 g (0.20 mol) was slowly added dropwise. After the dropwise addition was completed, the mixture was stirred for an additional 4 hours while maintaining the temperature at 10° C. to completely react the 2-ethylhexyl alcohol.

Next, after heating the reaction solution to 40° C., 26.0 g (0.20 mol) of 2-ethylhexyl alcohol was slowly added dropwise.

After the dropwise addition was completed, the mixture was stirred for an additional 4 hours while maintaining the temperature at 40° C. to completely react the 2-ethylhexyl alcohol. 200 ml of water was added to the reaction solution, and the mixture was heated under reflux for 4 hours for hydrolysis.

Next, after distilling off excess water from the hydrolysis product, the residue was dried under reduced pressure to obtain 58.7 g (yield: 91%) of di-2-ethylhexyl phosphate.

The selectivity at this time was 97%.

Comparative Example 1 30.7 g (0.20 mol) of phosphorus oxychloride was put into a three-necked flask equipped with a thermometer and a stirrer, and after heating to 30°C, 2-ethylhexyl alcohol 2
6.0 g (0.20 mol) was slowly added dropwise. During the dropwise addition, the reaction solution turned brown. After dropping, lower the temperature to 30
The mixture was stirred for 2 hours while maintaining the temperature at 'C. At this time, since the phosphorus oxychloride was decomposed, a considerable amount of unreacted 2-ethylhexyl alcohol remained. Next, after heating the reaction solution to 40°C, 26.0 g of 2-ethylhexyl alcohol (0
, 20 mol) was slowly added dropwise. After the dropwise addition was completed, the mixture was stirred for an additional 2 hours while maintaining the temperature at 40°C.

After the reaction, the reaction mixture was treated in the same manner as in Example 1 to obtain 36.8 g of a brown paste-like substance containing 70% di-2-ethylhexyl phosphate.

Comparative Example 2 30.7 g (0.20 mol) of phosphorus oxychloride was placed in a three-necked flask equipped with a thermometer and a stirrer, and while maintaining the temperature at 10°C, 2-ethylhexyl alcohol 2
6°0 g (0.20 mol) was slowly added dropwise. After completion of the dropwise addition, the mixture was stirred for an additional 4 hours while maintaining the temperature at 10° C. to allow 2 to ethylhexyl alcohol to react completely.

Next, the reaction solution was heated to 20° C., and 26.0 g (0.20 mol) of 2-ethylhexyl alcohol was slowly added dropwise.

After completion of the dropwise addition, the mixture was stirred for an additional 8 hours while maintaining the temperature at 20°C, but unreacted 2-ethylhexyl alcohol remained and the reaction did not occur completely. After the reaction, the same treatment as in Example 1 resulted in 35% monoester and 65% diester.
% mixed ester was obtained.

Example 2 30.7 g (0.20 mol) of phosphorus oxychloride was placed in a three-necked flask equipped with a thermometer and a stirrer, and while maintaining the temperature at 10°C, 26.0 g of 2-octyl alcohol was added.
g (0.20 mol) was slowly added dropwise. After the dropwise addition was completed, the temperature was maintained at 10°C and the mixture was stirred for an additional 4 hours.
The octyl alcohol was completely reacted. Next, after heating the reaction solution to 30°C, 26.0% of 2-octyl alcohol was added.
g (0.20 mol) was slowly added dropwise. After the completion of the dropwise addition, the mixture was stirred for an additional 5 hours while maintaining the temperature at 30°C to completely react the 2-octyl alcohol. 20% water to reaction solution
0ml was added and refluxed for 4 hours for hydrolysis.

Next, after distilling off excess water from the hydrolysis product, the residue was dried under reduced pressure to obtain 60.0 g (yield: 93%) of di-2-octyl phosphate. The selectivity at this time was 97%.

Example 3 Put 30.7 g (0.20 mol) of phosphorus oxychloride into a three-necked flask equipped with a thermometer and a stirrer, and add 31.3 g (0.20 mol) of dl-menthol while keeping the temperature at 10°C.
, 20 mol) was slowly added dropwise. After the dropwise addition, the temperature was maintained at 10'C and the mixture was stirred for an additional 4 hours.
The menthol was completely reacted. Next, after heating the reaction solution to 50°C, 31.3 g (0.20 m
ol) was slowly added dropwise. After completion of the dropwise addition, the mixture was stirred for an additional 4 hours while maintaining the temperature at 50° C. to completely react di-menthol. 300 ml of water was added to the reaction solution, and the mixture was refluxed for 2 hours for hydrolysis.

Next, after distilling off excess water from the hydrolysis product, the residue was dried under reduced pressure to obtain cymentyl phosphate 7.
1.2 g (yield 95.1%) was obtained. The selectivity at this time was 96%.

Example 4 30.7 g (0.20 mol) of phosphorus oxychloride was put into a 7-piece tank equipped with a thermometer and a stirrer, and while maintaining the temperature at 10°C, 2-methylcyclohexanol 2
4.0 g (0.20 mol) was slowly added dropwise. After the dropwise addition was completed, the temperature was maintained at 10°C and the mixture was stirred for 2 hours.
Methylcyclohexanol was completely reacted. Next, after heating the reaction solution to 40° C., 27.3 g (0.20 mol) of 2-ethylhexyl alcohol was slowly added dropwise. After the dropwise addition was completed, the mixture was stirred for an additional 2 hours while maintaining the temperature at 40° C. to completely react the 2-ethylhexyl alcohol. 300 ml of water was added to the reaction solution, and the mixture was refluxed for 2 hours for hydrolysis.

Next, after distilling off excess water from the hydrolysis product, the residue was dried under reduced pressure to obtain 57.6 g of (2-methylcyclohexyl)(2-ethylhexyl)phosphate (
A yield of 93.9%) was obtained. The selectivity at this time was 97%.

Claims (1)

[Claims] (1) In a method of reacting phosphorus oxyhalide and an organic hydroxyl compound and then hydrolyzing if necessary to obtain a phosphoric acid ester, substantially the same equivalent amount of the organic hydroxyl compound to phosphorus oxyhalide is reacted at a reaction temperature. A phosphate ester characterized by adding and reacting while maintaining the temperature at 15°C or lower, and then adding and reacting substantially the same or twice the equivalent of the same or different organic hydroxyl compound as above at 30°C or higher. Production method.