JPS59111906A - Production of nitrosodisulfonate - Google Patents

Abstract

PURPOSE:The reaction between hydroxylamine disulfonate and a nitrite salt is effected in a reaction system whose pH is kept at a specific value by addition of an inorganic acid and the resultant reaction mixture is combined with an alkaline substance to enable easy and inexpensive production of the titled compound through simple oprations. CONSTITUTION:As the reaction system is kept in pH at 1-5 by addition of an inorganic acid, the reaction between a hydroxylamine disulfonate of formula I (X is ammonium ion, alkali or alkaline earth metal; m is 2, when X is ammonium ion or alkali metal, or 1, when X is alkaline earth metal) and a nitrite salt. Then, the resultant reaction mixture containing O-nitroso-disulfonate is combined with an alkaline substance to give a nitrosodisulfonate of formula II.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a process for making dil-Lodge sulfonates.

Nitrosodisulfonates are useful as oxidizing agents, such as oxidizing agents for phenols.

The conventional method for producing nitrone disulfonates is as follows.

For example, a method of oxidizing hydroxylamine disulfonates with a strong oxidizing agent such as lead dioxide, silver oxide, or potassium permanganate, a method of electrolyzing hydroxylamine disulfonates (Japanese Patent Publication No. 47-27633), etc. It has been known.

The present inventors have conducted extensive research with the aim of developing an economical method for producing nitrone disulfonates without the need for strong oxidizing agents or electrolytic equipment as in conventional methods. reached.

In the present invention, an inorganic acid is added to the reaction system, the pH is maintained at 1 to 5, and hydroxylamine disulfonates and nitrite are reacted, resulting in a reaction solution containing ○-nitrosohydroxylamine disulfonates. The present invention relates to a method for producing nitrosodisulfonates, which comprises adding an alkaline substance to produce nitrosodisulfonates.

According to the present invention, without using a strong oxidizing agent or electrolytic equipment,
Nitrosodisulfonates can be easily produced by simple operations.

The hydroxylamine disulfonates used in the present invention can be represented by formula (1).

HON(SO2)2Xm ---'---- (
1) (In the formula, X represents an ammonium ion, an alkali metal or an alkaline earth metal, and 9m is 2 when X is an ammonium ion or an alkali metal.

When X is an alkaline earth metal, it is 1. ) Hydroxylamine disulfonates can be obtained by absorbing sulfur dioxide gas into an aqueous solution of nitrite 1, such as ammonium nitrite, alkali metal nitrite, alkaline earth metal nitrite, etc., according to a conventionally known method. 9
In the present invention, the absorption liquid containing the produced hydroxylamine disulfonates may be used as is.

Examples of nitrites to be reacted with hydroxylamine disulfonates include ammonium nitrite, nitrites of alkali metals such as sodium, potassium, and rubidium, calcium, and strontium.

Nitrites of alkaline earth metals such as barium and magnesium are effective, and ammonium nitrite and nitrites of alkali metals are particularly preferred.

The appropriate amount of nitrite to be used is generally 0.05 to 1 mole per mole of hydroxylamine disulfonate, since nitrogen oxide gas will be generated if the amount is too large.

As the inorganic acid added to the reaction system, mineral acids such as phosphoric acid, hydrochloric acid, nitric acid, and sulfuric acid are effective. The amount of inorganic acid added is 9. The pH of the reaction system is 1 to 5. Preferably, the amount may be such that it can be maintained at 1.5 to 4. If an inorganic acid is not added or its amount is too small, the pH of the reaction system will shift to the alkaline side due to alkali hydroxide produced as a by-product in the reaction between hydroxylamine disulfonates and nitrites.
Not only does the reaction rate slow down, but one reaction takes a long time, and hydroxylamine disulfonates may decompose.
Since nitrite may be decomposed, it is preferable to add an inorganic acid so that the two reaction system can be maintained at the above pH.

The reaction temperature when reacting hydroxylamine disulfonates and nitrite is -10 to 40°C.

Preferably, it is appropriate to maintain the temperature at -10 to 25°C.

If the reaction temperature is too high, hydrolysis reaction of hydroxylamine disulfonates tends to occur, and it is also uneconomical to lower the reaction temperature too much. Although the reaction time depends on the pH of the reaction system, generally about 10 to 300 seconds is appropriate.

When hydroxylamine disulfonates and nitrite are reacted, 0-nitrone hydroxylamine disulfonates are produced.

ONON(803)2Xm + -X(OH)n (wherein, 2) When adding an alkaline substance to the reaction solution containing O-nitrosohydroxylamine disulfonates to produce nitrone disulfonates, the alkaline substances include ammonia, sodium hydroxide, potassium hydroxide, etc. It is preferable to add hydroxides of alkali metals such as hydroxides of alkali metals, hydroxides of alkaline earth metals such as calcium hydroxide, magnesium hydroxide, etc. to a concentration of 11, preferably 8.5 to 10.5. If the ipH of the reaction solution is too low or too high, it will be difficult to efficiently produce nitrosodisulfonates. The temperature when still adding an alkaline substance to produce nitron disulfonates is -10 to 40°C, preferably 0 to 60°C. If the temperature is too high, the desired product, nitrosodisulfonate, will be easily decomposed, so it is appropriate to maintain the temperature at the above temperature. The production of nitrone disulfonates can be easily confirmed by observing the hue of the two reaction solutions. That is, O-
The reaction solution containing nitrosohydroxylamine disulfonates is brown in color, but as the nitrosodisulfonates are produced, the reaction solution becomes purple.

In the present invention, in order to effectively produce nitrone disulfonates, it is necessary to add an alkaline substance to adjust the pH of the reaction solution to 8 to 11, and then add an inert gas to the reaction.
For example, it is desirable to introduce and bubble an inert gas such as air, nitrogen, helium, or argon into the reaction solution.

In the present invention, when an alkaline substance is added to the reaction solution containing 0-nitrosohydroxylamine disulfonates, No gas is generated and nitrone disulfonates are produced.
This may be isolated from the reaction solution and used as an oxidizing agent, or the reaction solution containing the nidrozzyl sulfonate may be used as an oxidizing agent as it is.

Isolation of nitron disulfonate M from the reaction solution 9 For example, method 1 of cooling the reaction solution to precipitate and separate crystals of nitrosodisulfonates 1 Adding an alkali metal salt such as potassium chloride, potassium nitrate, or potassium sulfate to the reaction solution. In addition, due to the salting-out effect, it can be easily carried out by methods such as precipitating and separating crystals of nitrosodisulfonates.

Nitrosodisulfonates can be represented by formula 6 (2).

ON(803)2Xm ----(2) (wherein, Density 0.4mob/7
100 mg of potassium salt aqueous solution of hydroxylamine disulfonate was prepared, and 1.77 mg of potassium nitrite was added to this.
was added, and further 10 ml of 1N sulfuric acid was added to adjust the pH of the reaction system to 2.7, and the reaction was carried out at 25°C for 60 seconds to produce potassium salt of 0-nitrosohydroquinylamine disulfone-1.

Next, 0.45 f of potassium hydroxide was added to the reaction solution (2
After adjusting the pH at 5°C to 10.5, add 1 part of air into the reaction solution.
Bubbling was carried out for 10 minutes at a flow rate of 0 t/hr.

In the reaction solution, 6 mmot of potassium salt of nitrone disulfonate was produced. The analysis and quantitative determination of nitrosodisulfonate was carried out by measuring the absorbance at a wavelength of 545 nm and 771 nm and determining the concentration of nitron disulfonate from a linear equation.

A = εCd (In the formula, A is the absorbance, ε is the extinction coefficient, d is the thickness of the absorbing layer cell, and C is the concentration of nitrosodisulfonate.) The reaction solution was still cooled to 0°C and the precipitated crystals were filtered. Separately, crystals (yellow brown) of potassium salt of nitrosodisulfonate were obtained.

Example 2 Ammonium salt aqueous solution of hydroxylamine disulfonate (1:1H=2.2) ioo with a concentration of 2rnol/l
Keep the temperature at 0 °C, add 50 Wl of ammonium nitrite aqueous solution with a concentration of 2.5 mol/t, and add 6 ml of concentrated sulfuric acid.
was added, the pH was maintained at 2.5, and the reaction was carried out for 20 seconds at 0°C to produce an ammonium salt of 0-nitrone hydroxylamine disulfonate. Then, at the same temperature, 5 ml of ammonia water with a concentration of 28% by weight was added. to adjust the pH of the reaction solution to 9.1.
Then, 10 tons of air was bubbled into the reaction solution to generate ammonium salt of nitrosodisulfonate. In the reaction solution, 158 mm0/- of ammonium salt of nitrosodisulfonate was produced.

Claims (1)

[Scope of Claims] An inorganic acid is added to the reaction system, the pH is maintained at 1 to 5, and hydroxylamine disulfonates and nitrite are reacted. 1. For the reaction solution containing the group. A method for producing nitrosodisulfonates, which comprises adding an alkaline substance to produce nitrosodisulfonates.