JP4624914B2 - Hydroxylamine stabilizer, stabilization method and stabilized hydroxylamine solution - Google Patents

Description

  The present invention relates to a hydroxylamine stabilizer, a stabilization method, and a stabilized hydroxylamine solution.

  Hydroxylamines are used in a wide range of industrial applications such as raw materials for pharmaceutical and agrochemical intermediates, reducing agents, metal surface treatment agents, fiber treatment, and dyeing. In general, a relatively stable salt of hydroxylamine is produced and used because it has very unstable properties such as being easily decomposed under conditions such as high temperature or high concentration in the presence of heavy metal ions). Yes.

  However, in many applications, hydroxylamine is preferred over hydroxylamine salts, and further handling of aqueous hydroxylamine at high temperatures or concentrations is often required. For this reason, attempts have been made to stabilize hydroxylamine under conditions such as high temperature, high concentration, and conditions in which metal impurities such as Fe are mixed.

  For example, Patent Document 1 (Japanese Patent Publication No. 52-48118) discloses a hydroxyl group and / or a salt thereof, or a hydroxyl group in each of two or more consecutive carbon atoms on an aromatic ring in a solution containing hydroxylamine. A stabilizing method is described in which an aromatic compound substituting is added as a stabilizer.

  However, a hydroxylamine solution containing pyrogallol, catechol, 4-tert-butylcatechol, 2,3-dihydroxynaphthalene, 2,3-dihydroxybenzoic acid as a stabilizer has high temperature, high concentration, and metal impurities such as Fe. When mixed, there was a problem that the effect of suppressing the decomposition of hydroxylamine was insufficient.

Furthermore, the hydroxylamine solution containing the stabilizer described in Patent Document 1 has a problem that it is colored at a high temperature or a high concentration.
Japanese Patent Publication No. 52-48118

  It is an object of the present invention to provide a hydroxylamine stabilizer, a stabilization method, and a stabilized hydroxylamine solution.

  As a result of intensive studies to solve the above problems, the present inventors have found that the hydroxylamine solution can be stabilized by adding 3,4-dihydroxybenzoic acid to the hydroxylamine solution.

  Furthermore, by adding 3,4-dihydroxybenzoic acid and an antioxidant to the hydroxylamine solution, it was found that the hydroxylamine solution was further stabilized, and the present invention was completed. These findings have been found for the first time by the present inventors.

This invention is made | formed based on the said knowledge, and relates to the following (1)-( 9 ).
(1) A method for stabilizing hydroxylamine, comprising adding 3,4-dihydroxybenzoic acid as a storage stabilizer to a hydroxylamine solution.
(2) The method for stabilizing hydroxylamine according to (1), wherein an antioxidant is further added.
(3) The antioxidant is alcohol, phenol derivative, ethylenic double bond-containing compound, acetylenic triple bond-containing compound, nitrile compound, sulfur-containing compound (sulfur-containing organic compound) , nitrogen-containing compound (nitrogen-containing organic compound) ) And a phosphorus-containing compound (phosphorus-containing organic compound) . The method for stabilizing hydroxylamine according to (2), which is at least one compound selected from the group consisting of:
(4) The sulfur-containing organic compound is phenothiazine, 2,2′-dibenzothiazolyl disulfide, 2-mercaptobenzothiazole, 2-mercaptobenzimidazole, 2-mercaptobenzothiazole sodium salt, thiouric acid, bismuthiol, distearyl. −3,3′-thiodipropionate, dilauryl-3,3′-thiodipropionate, dimyristyl-3,3′-thiodipropionate, cysteine, cystine, dimercaptosuccinic acid, 2-aminoethanethiol, At least one selected from toluene-3,4-dithiol and furfuryl mercaptan;
The nitrogen-containing organic compound is 1,1-diphenyl-2-picryl-hydrazyl, N-nitroso-diphenylamine, 4-nitrosodiphenylamine, 2-methyl-2-nitrosopropane, α-phenyl (t-butyl) nitrone, N -Phenyl-N'-i-propylphenylenediamine, 5,5-dimethyl-N-phenyl-N'-i-propylphenylenediamine, 1-nitroso-2-naphthol, 2-nitroso-1-naphthol, nitrosobenzene and At least one selected from diphenylamine,
The phosphorus-containing organic compound is triethylphosphine, triphenylphosphine, trimethylphosphite, triethylphosphite, triphenylphosphite, distearylpentaerythritol diphosphite, diphenyl-i-octylphosphite and tris (2,4 -The method for stabilizing hydroxylamine according to (3), which is at least one selected from di-t-butylphenyl) phosphite.
( 5 ) A stabilized hydroxylamine solution comprising hydroxylamine and 3,4-dihydroxybenzoic acid.
( 6 ) The stabilized hydroxylamine solution according to ( 5 ), further comprising an antioxidant.
( 7 ) The antioxidant is an alcohol, a phenol derivative, an ethylenic double bond-containing compound, an acetylenic triple bond-containing compound, a nitrile compound, a sulfur-containing compound (a sulfur-containing organic compound) , a nitrogen-containing compound (a nitrogen-containing organic compound) ) And a phosphorus-containing compound (phosphorus-containing organic compound) . The stabilized hydroxylamine solution according to ( 6 ), which is at least one compound selected from the group consisting of:
( 8 ) The sulfur-containing organic compound is phenothiazine, 2,2′-dibenzothiazolyl disulfide, 2-mercaptobenzothiazole, 2-mercaptobenzimidazole, 2-mercaptobenzothiazole sodium salt, thiouric acid, bismuthiol, distearyl. −3,3′-thiodipropionate, dilauryl-3,3′-thiodipropionate, dimyristyl-3,3′-thiodipropionate, cysteine, cystine, dimercaptosuccinic acid, 2-aminoethanethiol, At least one selected from toluene-3,4-dithiol and furfuryl mercaptan, and the nitrogen-containing organic compound is 1,1-diphenyl-2-picryl-hydrazyl, N-nitroso-diphenylamine, 4-nitroso Diphenylamine, 2-methyl-2 Nitrosopropane, α-phenyl (t-butyl) nitrone, N-phenyl-N′-i-propylphenylenediamine, 5,5-dimethyl-N-phenyl-N′-i-propylphenylenediamine, 1-nitroso-2 -At least one selected from naphthol, 2-nitroso-1-naphthol, nitrosobenzene and diphenylamine, and the phosphorus-containing organic compound is triethylphosphine, triphenylphosphine, trimethylphosphite, triethylphosphite, triphenyl (7) which is at least one selected from phosphite, distearyl pentaerythritol diphosphite, diphenyl-i-octyl phosphite and tris (2,4-di-t-butylphenyl) phosphite Stabilized hydroxy as described Amine solution.
( 9 ) A hydroxylamine stabilizer comprising 3,4-dihydroxybenzoic acid as an active ingredient.

  According to the present invention, a hydroxylamine solution can be stabilized and a stabilized hydroxylamine solution can be obtained.

Hereinafter, the hydroxylamine solution stabilizer, the stabilization method, and the stabilized hydroxylamine solution according to the present invention will be described in more detail.
The method for stabilizing hydroxylamine of the present invention is a method for stabilizing hydroxylamine by adding 3,4-dihydroxybenzoic acid as a storage stabilizer to a hydroxylamine solution.

Moreover, the stabilized hydroxylamine solution according to the present invention contains hydroxylamine and 3,4-dihydroxybenzoic acid.
In addition, the hydroxylamine stabilizer according to the present invention is characterized by using 3,4-dihydroxybenzoic acid as an active ingredient.

  The method for stabilizing hydroxylamine according to the present invention can be achieved by adding 3,4-dihydroxybenzoic acid to a hydroxylamine solution at a high temperature, a high concentration, and / or a condition in which metal impurities such as Fe are mixed. The decomposition of hydroxylamine can be suppressed. Moreover, coloring of the hydroxylamine solution at high temperature or high concentration can be prevented.

  The 3,4-dihydroxybenzoic acid used in the method of the present invention is not particularly limited as long as it is commercially available or industrially available, but preferably has few metal impurities. This is because the presence of metal impurities may accelerate the decomposition of hydroxylamine. Further, in the electronic industry, high-purity hydroxylamine with less metal impurities is preferable. Hydrates may be used for 3,4-dihydroxybenzoic acid.

The mass ratio of 3,4-dihydroxybenzoic acid to hydroxylamine (3,4-dihydroxybenzoic acid / hydroxylamine) is 1.0 × 10 ^{−9 to} 1.0, preferably 1.0 × 10 ⁻⁸ to 0.1 is suitable. When the mass ratio is smaller than 1.0 × 10 ^{−9, the} effect of suppressing the decomposition reaction of hydroxylamine may not be obtained. When the mass ratio is larger than 1.0, an excess of 3,4- Removal and recovery of dihydroxybenzoic acid may be necessary.

As a method of adding 3,4-dihydroxybenzoic acid to hydroxylamine, it may be added as a solid, or may be added after dissolved or suspended in a solvent. As such a solvent, water and / or an organic solvent can be used. Examples of the organic solvent include hydrocarbons, ethers, esters, alcohols and the like capable of dissolving 3,4-dihydroxybenzoic acid, but are not limited to these as long as the use is not affected. . In these, it is preferable to use water and / or alcohol. Further, it may be added by dissolving in a hydroxylamine solution. The solvent can be selected from the same type as the hydroxylamine solution or a different type depending on the situation and use. It is preferable to add it by dissolving in the same kind of solvent. And the quantity of a solvent can be selected suitably.

  In the method for stabilizing hydroxylamine of the present invention, 3,4-dihydroxybenzoic acid is added to a hydroxylamine solution together with an antioxidant to further suppress the decomposition of hydroxylamine under conditions such as high temperature or high concentration. can do. Furthermore, the decomposition of hydroxylamine by metal impurities such as Fe can be further suppressed.

This is considered to suppress 3,4-dihydroxybenzoic acid from being oxidized and deteriorated by hydroxylamine or air by adding an antioxidant.
Antioxidants that can be used in the method for stabilizing hydroxylamine of the present invention include alcohols, phenol derivatives, ethylenic double bond-containing compounds, acetylenic triple bond-containing compounds, nitrile compounds, sulfur-containing compounds, and nitrogen-containing compounds. And phosphorus-containing compounds.

The antioxidant used in the stabilization method of the present invention may be added singly or in combination of two or more.
The antioxidant used in the stabilization method of the present invention is not particularly limited as long as it is commercially available or industrially available, but preferably has few metal impurities. This is because the presence of metal impurities may accelerate the decomposition of hydroxylamine. Further, in the electronic industry, high-purity hydroxylamine with less metal impurities is preferable.

The mass ratio of antioxidant to hydroxylamine (antioxidant / hydroxylamine) is 1.0 × 10 ^{−9 to} 1.0, preferably 1.0 × 10 ^{−8 to} 0.1. When the mass ratio is smaller than 1.0 × 10 ^{−9, the} effect of suppressing the decomposition reaction of hydroxylamine may not be obtained. When the mass ratio is larger than 1.0, an excessive amount of antioxidant Removal or recovery may be required. In addition, since alcohol can also be used as a solvent capable of dissolving 3,4-dihydroxybenzoic acid added as a storage stabilizer, for example, when alcohol is used as such a solvent, The mass ratio is not limited to the above range.

The method of adding the antioxidant to hydroxylamine may be added as it is, or may be added after being dissolved or suspended in a solvent. As such a solvent, water and / or an organic solvent can be used. Examples of the organic solvent include hydrocarbons, ethers, esters, alcohols, and the like that can dissolve the antioxidant, but are not limited to these as long as the use is not affected. In these, it is preferable to use water and / or alcohol. Further, it may be added by dissolving in a hydroxylamine solution. The solvent can be selected from the same type as the hydroxylamine solution or a different type depending on the situation and use. It is preferable to add it by dissolving in the same kind of solvent. Furthermore, the same kind as what was used as a solvent of 3, 4- dihydroxy benzoic acid, or a different kind can be selected according to the condition, a use, etc. It is preferable to add it by dissolving together in the same type of solvent. And the quantity of a solvent can be suitably selected according to conditions, such as the kind and quantity of antioxidant to be used.

  Examples of alcohols that can be used as antioxidants in the method for stabilizing hydroxylamine of the present invention include methanol, ethanol, propanol, butanol, pentanol, cyclohexyl alcohol, furfuryl alcohol, tetrahydrofurfuryl alcohol, benzyl alcohol, and glycolic acid. And polyhydric alcohols such as ethylene glycol, propylene glycol, butanediol, hexanediol, cyclohexanediol, and glycerin. Also, glyceraldehyde, erythrose, threose, ribose, arabinose, xylose, lyxose, allose, altrose, glucose, mannose, gulose, idose, galactose, talose, dihydroxyacetone, erythrulose, ribulose, xylulose, psicose, fructose, sorbose, Monosaccharides such as tagatose, disaccharides such as maltose, cellobiose, lactose, sucrose, trehalose and saccharose can also be mentioned as polyhydric alcohols. Furthermore, erythritol, threitol, ribitol, arabinitol, xylitol, allitol, altritol, glucitol, mannitol, iditol, galactitol and the like, which are derivatives of the above monosaccharides and disaccharides, are also exemplified as polyhydric alcohols.

  Similarly, phenol derivatives that can be used as antioxidants include phenol, 4-t-butylphenol, 4-methoxyphenol, 2,6-di-t-butyl-4-methylphenol, 2-t- Butyl-4-methoxyphenol, 3-t-butyl-4-methoxyphenol, 2-t-butyl-4-methylphenol, 2,6-di-t-butylphenol, 2,4,6-trimethylphenol, 2- i-propyl-5-methylphenol, n-octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, tetrakis (methylene-3 (3 ′, 5′-di-t-butyl) -4′-hydroxyphenyl) propionate) methane, tris (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate DOO, hydroquinone, 2,5-di -t- butyl hydroquinone, 2,5-di -t- amyl hydroquinone, etc. tocopherol.

  Examples of the ethylenic double bond-containing compound include styrene, o-nitrostyrene, m-nitrostyrene, p-nitrostyrene, o-cyanostyrene, m-cyanostyrene, p-cyanostyrene, divinylbenzene, and p-styrene. Sulfonic acid, 2-vinylpyridine, 4-vinylpyridine, 2-vinyl-5-ethylpyridine, 2-methyl-5-vinylpyridine, acrylamide, methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate, allyl Alcohol, allyl acetate, acrylonitrile, etc. are mentioned.

  Examples of the acetylenic triple bond-containing compound include propargyl alcohol, 1-butyn-1-ol, 2-butyn-1-ol, 3-butyn-1-ol, 3-butyn-2-ol, and 2-butyne. -1,4-diol, 2-butyne-1,4-diol diacetate and the like.

  Examples of the nitrile compound include propionitrile, butyronitrile, isobutyronitrile, 3-methoxypropionitrile, malononitrile, adiponitrile, 1,6-dicyanohexane, 3-dimethylaminopropionitrile, benzonitrile, phthalonitrile, Examples include isophthalonitrile and terephthalonitrile.

Examples of the sulfur-containing compound include phenothiazine, 2,2′-dibenzothiazolyl disulfide, 2-mercaptobenzothiazole, 2-mercaptobenzimidazole, 2-mercaptobenzothiazole sodium salt, thiouric acid, bismuthiol, and distearyl-3. , 3′-thiodipropionate, dilauryl-3,3′-thiodipropionate, dimyristyl-3,3′-thiodipropionate, cysteine, cystine, dimercaptosuccinic acid, 2-aminoethanethiol, toluene- Examples include 3,4-dithiol and furfuryl mercaptan.

  Examples of nitrogen-containing compounds include 1,1-diphenyl-2-picryl-hydrazyl, N-nitroso-diphenylamine, 4-nitrosodiphenylamine, 2-methyl-2-nitrosopropane, α-phenyl (t-butyl) nitrone, N-phenyl-N′-i-propylphenylenediamine, 5,5-dimethyl-N-phenyl-N′-i-propylphenylenediamine, 1-nitroso-2-naphthol, 2-nitroso-1-naphthol, nitrosobenzene And diphenylamine.

  Examples of phosphorus-containing compounds include triethylphosphine, triphenylphosphine, trimethylphosphite, triethylphosphite, triphenylphosphite, distearylpentaerythritol diphosphite, diphenyl-i-octylphosphite, tris (2, 4-di-t-butylphenyl) phosphite.

  The hydroxylamine that can be used in the stabilization method of the present invention is not particularly limited as long as it is commercially available or industrially available, but preferably has few metal impurities. This is because the presence of metal impurities may accelerate the decomposition of hydroxylamine. Further, in the electronic industry, high-purity hydroxylamine with less metal impurities is preferable.

  In the stabilization method of the present invention, hydroxylamine may be used as a solid or may be used after being dissolved in a solvent. As such a solvent, water and / or an organic solvent can be used. Examples of the organic solvent include hydrocarbons, ethers, esters, alcohols and the like, but are not limited to these as long as the use is not affected. In these, it is preferable to use water and / or alcohol.

  The concentration of hydroxylamine in the hydroxylamine solution can be adjusted by appropriately selecting the amount of the solvent, and is not particularly limited, but is preferably 0.1% by mass to 90% by mass, and more preferably, It is 1.0 mass%-70 mass%.

Hydroxylamine that can be used in the stabilization method of the present invention can be produced, for example, by the following production method.
Reaction Step The method for producing hydroxylamine includes, for example, a reaction step in which a hydroxylamine salt is reacted with an alkali compound to obtain hydroxylamine.

Hydroxylamine salts include inorganic salts such as hydroxylamine sulfate, hydrochloride, nitrate, phosphate, hydrobromide, sulfite, phosphite, perchlorate, carbonate, bicarbonate, etc. Examples include salts of acids, and salts of organic acids such as formate, acetate, and propionate. Among these, hydroxylamine sulfate (NH ₂ OH · 1 / 2H ₂ SO ₄ ), hydrochloride (NH ₂ OH · HCl), nitrate (NH ₂ OH · HNO ₃ ) and phosphate (NH ₂ OH) • At least one salt selected from the group consisting of 1 / 3H ₃ PO ₄ ) is preferred.

The hydroxylamine salt is not particularly limited as long as it is commercially available or industrially available, but preferably has a small amount of metal impurities. This is because the presence of metal impurities may promote the decomposition of the hydroxylamine salt or hydroxylamine formed. However, impurities may be contained as long as they do not affect the decomposition of the hydroxylamine salt or hydroxylamine and can be removed by a purification process or the like, or have no problem in using hydroxylamine.

  The hydroxylamine salt may be used as a solid, or may be used by dissolving or suspending in a solvent. As such a solvent, water and / or an organic solvent can be used. Examples of the organic solvent include hydrocarbons, ethers, alcohols and the like, but are not limited to these as long as the reaction is not affected. In these, the solvent containing water and / or alcohol is preferable. Moreover, you may use at least one part of the filtrate which isolate | separated the insoluble salt etc. which arose in reaction as a solvent.

  The amount of the solvent may be appropriately selected according to the conditions such as the amount of hydroxylamine salt used and the reaction temperature. Usually, the mass ratio of the solvent to the hydroxylamine salt (solvent / hydroxylamine salt) is It is in the range of 0.1 to 1000, preferably 1 to 100.

The alkali compound is preferably at least one compound selected from the group consisting of compounds containing alkali metals, compounds containing alkaline earth metals, ammonia and amines.
Examples of the compound containing an alkali metal include oxides, hydroxides and carbonates of lithium, sodium, potassium, rubidium or cesium, preferably sodium or potassium hydroxides or carbonates.

  Examples of the compound containing an alkaline earth metal include oxides, hydroxides and carbonates of beryllium, magnesium, calcium, strontium or barium, and preferably oxides or hydroxides of magnesium, calcium, strontium or barium. It is a thing.

Ammonia may be used as a gas or a solution in which ammonia is dissolved, for example, an aqueous ammonia solution.
As amines, primary amines, secondary amines and tertiary amines can be used. The amine may be a monoamine, a polyamine such as a diamine or triamine having two or more amino groups in the molecule, and a cyclic amine.

Examples of the monoamine include methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, n-propylamine, di-n-propylamine, tri-n-propylamine, i-propylamine, and di-i-propylamine. , Tri-i-propylamine, n-butylamine, di-n-butylamine, tri-n-butylamine, i-butylamine, di-i-butylamine, tri-i-butylamine, sec-butylamine, di-sec-butylamine, Tri-sec-butylamine, tert-butylamine, di-tert-butylamine, tri-tert-butylamine, allylamine, diallylamine, triallylamine, cyclohexylamine, dicyclohexylamine, tricyclohexylamine , N-octylamine, di-n-octylamine, tri-n-octylamine, benzylamine, dibenzylamine, tribenzylamine, diaminopropylamine, 2-ethylhexylamine, 3- (2-ethylhexyloxy) propyl Amine, 3-methoxypropylamine, 3-ethoxypropylamine, 3- (diethylamino) propylamine, bis (2-ethylhexyl) amine, 3- (dibutylamino) propylamine, α-phenylethylamine, β-phenylethylamine, aniline N-methylaniline, N, N-dimethylaniline, diphenylamine, triphenylamine, o-toluidine, m-toluidine, p-toluidine, o-anisidine, m-anisidine, p-anisidine, o-chloroaniline, m- Chloroa Phosphorus, p-chloroaniline, o-bromoaniline, m-bromoaniline, p-bromoaniline, o-nitroaniline, m-nitroaniline, p-nitroaniline, 2,4-dinitroaniline, 2,4,6- Examples thereof include trinitroaniline, p-aminobenzoic acid, sulfanilic acid, sulfanilamide, monoethanolamine, diethanolamine, and triethanolamine.

  Examples of the diamine include 1,2-diaminoethane, N, N, N ′, N′-tetramethyl-1,2-diaminoethane, N, N, N ′, N′-tetraethyl-1,2-diamino. Ethane, 1,3-diaminopropane, N, N, N ′, N′-tetramethyl-1,2-diaminopropane, N, N, N ′, N′-tetraethyl-1,2-diaminopropane, 1, 4-diaminobutane, N-methyl-1,4-diaminobutane, 1,2-diaminobutane, N, N, N ′, N′-tetramethyl-1,2-diaminobutane, 3-aminopropyldimethylamine, Examples include 1,6-diaminohexane, 3,3-diamino-N-methyldipropylamine, 1,2-phenylenediamine, 1,3-phenylenediamine, 1,4-phenylenediamine, and benzidine.

  Examples of the triamine include 2,4,6-triaminophenol, 1,2,3-triaminopropane, 1,2,3-triaminobenzene, 1,2,4-triaminobenzene, 1,3, 5-triaminobenzene and the like can be mentioned.

Examples of tetraamine include β, β ′, β ″ -triaminotriethylamine and the like.
Examples of the cyclic amine include pyrrole, pyridine, pyrimidine, pyrrolidine, piperidine, purine, imidazole, oxazole, thiazole, pyrazole, 3-pyrroline, quinoline, isoquinoline, carbazole, piperazine, pyridazine, 1,2,3-triazine, 1,2,4-triazine, 1,3,5-triazine, 1,2,3-triazole, 1,2,5-triazole, 1,2,4-triazole, 1,3,4-triazole, morpholine, etc. Is mentioned.

  The amine that can be used as the alkali compound is not limited to the above-mentioned compound, and may be an asymmetric compound having different types of substituents, such as ethylmethylamine. Moreover, an amine may be used individually by 1 type and may be used in combination of 2 or more type.

The alkali compound is not particularly limited as long as it is commercially available or industrially available, but preferably has a small amount of metal impurities like the hydroxylamine salt.
The equivalent ratio of the alkali compound to the hydroxylamine salt (alkali compound / hydroxylamine salt) is in the range of 0.1 to 100, preferably 0.5 to 10, and more preferably 1 to 2. The equivalent weight is calculated as 1 for an alkali metal, 1 for an alkaline metal, 2 for an alkaline earth metal, 1 for ammonia, 1 for an amine, and 2 for a diamine, for example. .

  If the equivalent ratio is greater than 100, problems such as decomposition of hydroxylamine by excess alkali compounds and recovery of many unreacted alkali compounds may occur. On the other hand, if the equivalent ratio is less than 0.1, there may be a problem that a large amount of unreacted hydroxylamine salt needs to be recovered.

  The alkaline compound can be used by dissolving or suspending it in a solvent. As such a solvent, water and / or an organic solvent can be used. Examples of the organic solvent include hydrocarbons, ethers, alcohols and the like, but are not limited to these as long as the reaction is not affected. In these, it is preferable to use water and / or alcohol. Moreover, you may use at least one part of the filtrate which isolate | separated the insoluble salt etc. which arose in reaction as a solvent.

  The amount of the solvent may be appropriately selected according to conditions such as the amount of the alkali compound to be used and the reaction temperature, and the mass ratio of the solvent to the alkali compound (solvent / alkali compound) is usually 0.5 to 1000, Preferably it is 0.8-100.

In the method for producing hydroxylamine, the reaction step for obtaining hydroxylamine by reacting a hydroxylamine salt with an alkali compound and the separation step, purification step and concentration step described later can be carried out in the presence of a stabilizer. A well-known thing can be used for a stabilizer. For example, 8-hydroxyquinoline, N-hydroxyethylethylenediamine-N, N, N′-triacetic acid, glycine, ethylenediaminetetraacetic acid, cis-1,2-diaminocyclohexane-N, N, N ′, N′-tetraacetic acid , Trans-1,2-diaminocyclohexane-N, N, N ′, N′-tetraacetic acid, N, N′-di (2-hydroxybenzyl) ethylenediamine-N, N′-diacetic acid, N-hydroxyethylimino Diacetic acid, N, N′-dihydroxyethylglycine, diethylenetriaminepentaacetic acid, ethylenebis (oxyethylenenitrilo) tetraacetic acid, bishexamethylenetriaminepentaacetic acid, hexamethylenediaminetetraacetic acid, triethylenetetraminehexaacetic acid, tris Ethyl) amine hexaacetic acid, iminodiacetic acid, polyethyleneimine, polypropyleneimine, -Aminoquinoline, 1,10-phenanthroline, 5-methyl-1,10-phenanthroline, 5-chloro-1,10-phenanthroline, 5-phenyl-1,10-phenanthroline, hydroxyanthraquinone, 8-hydroxyquinoline-5 Sulfonic acid, 8-hydroxymethylquinoline, thioglycolic acid, thiopropionic acid, 1-amino-2-mercapto-propionic acid, 2,2-dipyridyl, 4,4-dimethyl-2,2-dipyridyl, ammonium thiosulfate, benzo Triazole, flavone, morin, quercetin, gossypetin, robitinen, luteolin, fisetin, apigenin, galangin, chrysin, flavonol, pyrogallol, oxyanthraquinone, 1,2-dioxyanthraquinone, 1,4-dioxyanthraki 1,2,4-trioxyanthraquinone, 1,5-dioxyanthraquinone, 1,8-dioxyanthraquinone, 2,3-dioxyanthraquinone, 1,2,6-trioxyanthraquinone, 1,2, 7-trioxyanthraquinone, 1,2,5,8-tetraoxyanthraquinone, 1,2,4,5,8-pentaoxyanthraquinone, 1,6,8-dioxy-3-methyl-6-methoxyanthraquinone, quinalizarin , Flavan, lactone, 2,3-dihydrohexono-1,4-lactone, 8-hydroxyquinaldine, 6-methyl-8-hydroxyquinaldine, 5,8-dihydroxyquinaldine, anthocyan, pelargonidin, cyanidin, delphinidin, peonidin , Petunidin, malvidin, catechin, sodium thiosulfate, Trilotriacetic acid, 2-hydroxyethyl disulfide, 1,4-dimercapto-2,3-butanediol, thiamine hydrochloride, catechol, 4-t-butylcatechol, 2,3-dihydroxynaphthalene, 2,3-dihydroxybenzoic acid Acid, 2-hydroxypyridine-N-oxide, 1,2-dimethyl-3-hydroxypyridin-4-one, 4-methylpyridine-N-oxide, 6-methylpyridine-N-oxide, 1-methyl-3- Hydroxypyridin-2-one, 2-mercaptobenzothiazole, 2-mercaptocyclohexylthiazole, 2-mercapto-6-t-butylcyclohexylthiazole, 2-mercapto-4,5-dimethylthiazoline, 2-mercaptothiazoline, 2-mercapto -5-t-butylthiazoline, tetrame Ruthiuram disulfide, tetra-n-butylthiuram disulfide, N, N'-diethylthiuram disulfide, tetraphenylthiuram disulfide, thiuram disulfide, thiourea, N, N'-diphenylthiourea, di-o-tolylthiourea, ethylenethiourea Thiocetamide, 2-thiouracil, thiocyanuric acid, thioformamide, thioacetamide, thiopropionamide, thiobenzamide, thionicotinamide, thioacetanilide, thiobenzanilide, 1,3-dimethylthiourea, 1,3-diethyl-2-thio Urea, 1-phenyl-2-thiourea, 1,3-diphenyl-2-thiourea, thiocarbazide, thiosemicarbazide, 4,4-dimethyl-3-thiosemicarbazide, 2-mercaptoimidazoline, 2-thiohydra Knights Inn, 3- Chiourazoru, 2- Chiouramiru, 4 Chiouramiru, thio pentanol, 2
-Thiobarbituric acid, thiocyanuric acid, 2-mercaptoquinoline, thiocoumazone, thiocomothiazone, thiosaccharin, 2-mercaptobenzimidazole, trimethylphosphite, triethylphosphite, triphenylphosphite, trimethylphosphine, triethylphosphine, triphenylphosphine, etc. Is mentioned. Moreover, 3,4-dihydroxybenzoic acid can also be used as a stabilizer.

  The said stabilizer may be used individually by 1 type, and may be used in combination of 2 or more type. By adding a stabilizer, the decomposition of the hydroxylamine salt or hydroxylamine by metal impurities or the like can be suppressed.

The stabilizer is not particularly limited as long as it is commercially available or industrially available. However, like the hydroxylamine salt, the stabilizer preferably has few metal impurities.
The mass ratio between the stabilizer and the hydroxylamine salt (stabilizer / hydroxylamine salt) is suitably 1.0 × 10 ^{−9 to} 1.0, preferably 1.0 × 10 ^{−8 to} 0.1. Yes. When the mass ratio is smaller than 1.0 × 10 ^{−9, the} effect of suppressing the decomposition reaction of the hydroxylamine salt or hydroxylamine by metal impurities may not be obtained, and the mass ratio is larger than 1.0. In some cases, it may be necessary to remove or recover excess stabilizer.

  The stabilizer may be used as a solid or may be used after being dissolved in a solvent. As such a solvent, water and / or an organic solvent can be used. Examples of the organic solvent include hydrocarbons, ethers, esters, alcohols and the like, but are not limited to these as long as the reaction is not affected. In these, it is preferable to use water and / or alcohol. The amount of the solvent can be appropriately selected according to conditions such as the type and amount of the stabilizer used and the reaction temperature.

  The method for producing hydroxylamine is preferably a reaction step in which a salt of hydroxylamine is added to react with a reaction solution in which an alkali compound is dissolved or suspended in a solvent. Thus, by using a method of adding a hydroxylamine salt to a reaction solution containing an alkali compound, it is difficult for the produced hydroxylamine to form a complex with a by-product salt, and a by-product is insoluble. It becomes difficult to be adsorbed or taken in by the salt.

  Furthermore, when adding a hydroxylamine salt to a reaction solution containing an alkali compound, the pH of the reaction solution is preferably 7 or more, more preferably 7.5 or more, and even more preferably 8 or more, while the hydroxylamine salt is maintained. It is desirable to add. By maintaining the pH of the reaction solution in the above range, the produced hydroxylamine is less likely to form a complex with the by-produced salt, and is difficult to be adsorbed or incorporated into the by-produced insoluble salt.

However, the reaction step may be performed by adding an alkali compound to a reaction solution in which a hydroxylamine salt is dissolved or suspended.
Furthermore, the reaction step in the method for producing hydroxylamine may be a reaction step in which a hydroxylamine salt and an alkali compound are simultaneously supplied and reacted. At that time, it is desirable to adjust the addition amount of the hydroxylamine salt and the alkali compound while keeping the pH of the reaction solution at preferably 7 or more, more preferably 7.5 or more, and even more preferably 8 or more. The hydroxylamine salt and the alkali compound may be added as they are, or may be added after dissolved or suspended in a solvent. Further, when the alkali compound is ammonia or the like, it may be introduced by gas.

The method for adding the stabilizer in the reaction step in the method for producing hydroxylamine is not particularly limited, and can be performed by a known method. For example, it may be introduced into the reactor in advance to start the reaction, or may be added during the reaction as necessary. Further, the stabilizer may be added by dissolving or suspending it in a solvent together with an alkali compound and a salt of hydroxylamine.

  In the reaction step, the reaction temperature is preferably from 0 ° C to 80 ° C, more preferably from 5 ° C to 50 ° C. When the reaction temperature is higher than 80 ° C., problems such as decomposition of hydroxylamine may occur. On the other hand, when the reaction temperature is lower than 0 ° C., the reaction rate becomes slow and problems such as a decrease in productivity may occur.

  The reaction heat generated with the reaction between the salt of hydroxylamine and the alkali compound can be kept out of the system with water, hot water or a heat medium, so that the reaction temperature can be kept within a certain range. Moreover, it is preferable to use the heat | fever discharged | emitted out of the system with water, warm water, or a heat medium as a heat source of another installation.

The reaction step in the method for producing hydroxylamine can be performed by a known method, for example, a batch system, a semi-batch system, a continuous system, or the like.
Separation step The method for producing hydroxylamine may include, for example, a step of separating hydroxylamine from an insoluble substance.

This insoluble substance is, for example, an insoluble substance deposited in the reaction solution in the above reaction step.
Examples of the insoluble substance include a salt produced by the reaction of a hydroxylamine salt with an alkali compound in the above reaction step, a hydroxylamine salt, an alkali compound, and the like.

  That is, in the case where the salt formed by the reaction of hydroxylamine salt and alkali compound in the above reaction step, hydroxylamine salt, alkali compound, etc. is precipitated as an insoluble substance due to its concentration higher than the solubility, it is insoluble. A separation step of separating the substance may be included.

  As a separation method, known methods such as filtration, squeezing, centrifugation, sedimentation separation, and flotation separation can be used. For example, the separation by filtration may be performed by any of natural filtration, pressure filtration, or vacuum filtration, and the separation by sedimentation separation may be performed by any of clarification separation or precipitation concentration, by floating separation. Separation may be performed by any method of pressure levitation and ionization levitation.

In addition, by washing the insoluble material separated in the separation step with a solvent, hydroxylamine attached to or taken in by the insoluble material can be recovered.
As the solvent for washing the insoluble substance, the same solvent as that used in the reaction step may be used, or another solvent may be used. As such a washing solvent, water and / or an organic solvent can be used. Examples of the organic solvent include hydrocarbons, ethers, esters, alcohols and the like, but are not limited to these as long as the recovery of hydroxylamine is not affected. In these, it is preferable to use water and / or alcohol as a washing | cleaning solvent. The amount of the washing solvent can be appropriately selected according to the type and amount of the insoluble substance, conditions such as separation.

The temperature at which the insoluble material is separated in the separation step is preferably 0 ° C to 80 ° C, more preferably 5 ° C to 50 ° C. When the temperature at the time of separation is higher than 80 ° C., problems such as decomposition of hydroxylamine may occur. On the other hand, when the temperature of the reaction solution is lower than 0 ° C., there may be a problem that energy required for cooling increases. A part or all of the filtrate from which the insoluble substances have been separated in the separation step and / or the filtrate from which the insoluble substances have been washed may be used as a solvent for dissolving or suspending the hydroxylamine salt and / or alkali compound as the reaction raw material. Good.

  The separation step is preferably performed in the presence of a hydroxylamine stabilizer as in the reaction step. A new stabilizer may be added in the separation step, or the stabilizer from the previous step may be used as it is.

  As the stabilizer, the same type as the stabilizer used in the reaction step or a different type can be selected according to the situation and use. By adding a stabilizer, side reactions such as decomposition of hydroxylamine due to metal impurities and the like are suppressed, and the production efficiency of hydroxylamine is improved.

The amount of stabilizer is such that the mass ratio of stabilizer to hydroxylamine (stabilizer / hydroxylamine) is in the range of 1.0 × 10 ^{−9 to} 1.0, preferably 1.0 × 10 ^{−8 to} 0.1. It is suitable to use so that it becomes inside. When the mass ratio is less than 1.0 × 10 ^{−9, the} effect of suppressing the decomposition reaction of hydroxylamine by metal impurities may not be obtained. When the mass ratio is greater than 1.0, excessive stability Removal or recovery of the agent may be necessary.

The separation step in the method for producing hydroxylamine can be performed by a known method, for example, a batch system, a semi-batch system, a continuous system, or the like.
Purification Step The method for producing hydroxylamine includes, for example, a purification step in which the hydroxylamine solution obtained as described above is purified by ion exchange.

As a method of ion exchange, it can be performed by a known method such as cation exchange, anion exchange, or chelate exchange.
Purification by cation exchange can be performed by a known method using a strong acid cation exchange resin, a weak acid cation exchange resin, or the like. It is preferable to use the cation exchange resin in an H-type by performing an acid treatment in advance.

  Purification by anion exchange can be performed by a known method using a strongly basic anion exchange resin, a weakly basic anion exchange resin, or the like. It is preferable that the anion exchange resin is used after being alkali-treated in advance to form an OH type.

  Purification by chelate exchange can be performed by a known method using a chelate exchange resin or the like. The chelate exchange resin is preferably subjected to acid treatment in advance and used as an H type.

  You may refine | purify combining cation exchange, anion exchange, and chelate exchange. For example, anion exchange may be performed after cation exchange, and cation exchange may be performed after anion exchange. Moreover, it is also possible to use a monobed resin or a mixed bed resin in which a cation exchange resin and an anion exchange resin are mixed.

  The ion exchange temperature is preferably 0 ° C to 70 ° C, more preferably 5 ° C to 50 ° C. When the temperature of ion exchange is higher than 70 ° C., problems such as decomposition of hydroxylamine may occur. On the other hand, when the ion exchange temperature is lower than 0 ° C., there may be a problem that energy required for cooling becomes large.

  A part of the hydroxylamine solution obtained in the purification step may be used as a solvent for dissolving or suspending the hydroxylamine salt and / or alkali compound as a reaction raw material.

  The purification step is preferably performed in the presence of a hydroxylamine stabilizer as in the reaction step. A stabilizer may be newly added in the purification step, or the stabilizer from the previous step may be used as it is.

  As the stabilizer, the same type as the stabilizer used in the reaction step or a different type can be selected according to the situation and use. By adding a stabilizer, side reactions such as decomposition of hydroxylamine due to metal impurities and the like are suppressed, and the production efficiency of hydroxylamine is improved.

The amount of stabilizer is such that the mass ratio of stabilizer to hydroxylamine (stabilizer / hydroxylamine) is in the range of 1.0 × 10 ^{−9 to} 1.0, preferably 1.0 × 10 ^{−8 to} 0.1. It is suitable to use so that it becomes inside. When the mass ratio is less than 1.0 × 10 ^{−9, the} effect of suppressing the decomposition reaction of hydroxylamine by metal impurities may not be obtained. When the mass ratio is greater than 1.0, excessive stability Removal or recovery of the agent may be necessary.

The step of purification by ion exchange in the method for producing hydroxylamine can be performed by a known method, for example, a batch system, a semi-batch system, a continuous system, or the like.
Concentration process Furthermore, the manufacturing method of hydroxylamine includes the process of concentrating hydroxylamine by tower distillation by distillation, for example.

The distillation can be performed by a known method such as simple distillation, multistage distillation, steam distillation, or flash distillation.
For example, a hydroxylamine solution having a high hydroxylamine concentration can be obtained from the bottom of the column by simple distillation or multistage distillation.

As the distillation column, a general plate column such as a bubble bell tray column, a stitch plate column, or a general packing such as a Raschig ring, a pearl ring, and a saddle body may be provided.
The distillation temperature is preferably 0 to 70 ° C., more preferably 5 to 60 ° C. at the bottom of the column. When the temperature at the bottom of the column is higher than 70 ° C., problems such as decomposition of hydroxylamine may occur. On the other hand, when the temperature at the bottom of the column is lower than 0 ° C., there may be a problem that a large amount of cooling energy is required.

Although the distillation pressure is determined by the relationship with temperature, the pressure at the bottom of the column is preferably 0.5 to 60 kPa, more preferably 0.8 to 40 kPa.
A part of the hydroxylamine solution obtained in the concentration step may be used as a solvent for dissolving or suspending the hydroxylamine salt and / or alkali compound as a reaction raw material.

  In addition, a low concentration hydroxylamine solution may be obtained from the top or side of the distillation column, but a part or all of this dissolves or suspends the hydroxylamine salt and / or alkali compound as a reaction raw material. It may be used as a solvent.

  The concentration step is preferably performed in the presence of a hydroxylamine stabilizer as in the reaction step. A stabilizer may be newly added in the concentration step, or the stabilizer from the previous step may be used as it is.

As the stabilizer, the same type as the stabilizer used in the reaction step or a different type can be selected according to the situation and use. By adding a stabilizer, side reactions such as decomposition of hydroxylamine due to metal impurities and the like are suppressed, and the production efficiency of hydroxylamine is improved.

The amount of stabilizer is such that the mass ratio of stabilizer to hydroxylamine (stabilizer / hydroxylamine) is in the range of 1.0 × 10 ^{−9 to} 1.0, preferably 1.0 × 10 ^{−8 to} 0.1. It is suitable to use so that it becomes inside. When the mass ratio is less than 1.0 × 10 ^{−9, the} effect of suppressing the decomposition reaction of hydroxylamine by metal impurities may not be obtained. When the mass ratio is greater than 1.0, excessive stability Removal or recovery of the agent may be necessary.

The concentration step of concentrating at the bottom of the column by distillation in the method for producing hydroxylamine can be performed by a known method, for example, a batch method, a semi-batch method, a continuous method, or the like.
Furthermore, the method for producing hydroxylamine may include a purification step for purifying the hydroxylamine obtained in the concentration step by ion exchange.

As a method of ion exchange, it can be performed by a known method such as cation exchange, anion exchange, or chelate exchange.
Purification by cation exchange can be performed by a known method using a strong acid cation exchange resin, a weak acid cation exchange resin, or the like. It is preferable to use the cation exchange resin in an H-type by performing an acid treatment in advance.

  Purification by anion exchange can be performed by a known method using a strongly basic anion exchange resin, a weakly basic anion exchange resin, or the like. It is preferable that the anion exchange resin is used after being alkali-treated in advance to form an OH type.

  Purification by chelate exchange can be performed by a known method using a chelate exchange resin or the like. The chelate exchange resin is preferably subjected to acid treatment in advance and used as an H type.

  You may refine | purify combining cation exchange, anion exchange, and chelate exchange. For example, anion exchange may be performed after cation exchange, and cation exchange may be performed after anion exchange.

Moreover, it is also possible to use a monobed resin or a mixed bed resin in which a cation exchange resin and an anion exchange resin are mixed.
The ion exchange temperature is preferably 0 ° C to 70 ° C, more preferably 5 ° C to 50 ° C. When the temperature of ion exchange is higher than 70 ° C., problems such as decomposition of hydroxylamine may occur. On the other hand, when the ion exchange temperature is lower than 0 ° C., there may be a problem that energy required for cooling becomes large.

  A part of the hydroxylamine solution obtained in the purification step may be used as a solvent for dissolving or suspending the hydroxylamine salt and / or alkali compound as a reaction raw material.

  The purification step is preferably performed in the presence of a hydroxylamine stabilizer as in the reaction step. A stabilizer may be newly added in the purification step, or the stabilizer from the previous step may be used as it is.

As the stabilizer, the same type as the stabilizer used in the reaction step or a different type can be selected according to the situation and use. By adding a stabilizer, side reactions such as decomposition of hydroxylamine by metal ions and the like are suppressed, and the production efficiency of hydroxylamine is improved.

The amount of stabilizer is such that the mass ratio of stabilizer to hydroxylamine (stabilizer / hydroxylamine) is in the range of 1.0 × 10 ^{−9 to} 1.0, preferably 1.0 × 10 ^{−8 to} 0.1. It is suitable to use so that it becomes inside. When the mass ratio is less than 1.0 × 10 ^{−9, the} effect of suppressing the decomposition reaction of hydroxylamine by metal impurities may not be obtained. When the mass ratio is greater than 1.0, excessive stability Removal or recovery of the agent may be necessary.

As described above, the method for producing hydroxylamine that can be used in the stabilization method of the present invention includes, for example,
(1) A reaction step in which a hydroxylamine salt is reacted with an alkali compound to obtain hydroxylamine.
(2) A step of separating hydroxylamine and insoluble substances.
(3) A purification step for purifying hydroxylamine by ion exchange.
(4) A concentration step in which hydroxylamine is concentrated at the bottom of the column by distillation.
These steps are preferably performed in the order of a reaction step, a separation step, a purification step, and a concentration step. Moreover, each process of (1)-(4) may be performed in any order after performing the process of (1), and the same process may be performed twice or more.

  For example, the concentration of hydroxylamine obtained by using the above method is 10% by mass or more. Moreover, the hydroxylamine of the density | concentration of 20 mass% or more can be obtained, and the hydroxylamine of the density | concentration of 40 mass% or more can also be obtained.

  For example, the hydroxylamine obtained by using the above method has a content of each metal contained as an impurity of 1 mass ppm or less. Moreover, the hydroxylamine whose content of each metal is 0.1 mass ppm or less can be obtained, and the hydroxylamine whose content of each metal is 0.01 mass ppm or less can also be obtained. Examples of the metal include an alkali metal derived from the alkali compound used in the reaction step, an alkaline earth metal, and Fe that significantly accelerates the decomposition of hydroxylamine.

  For example, the hydroxylamine obtained by using the above method has a content of each anion contained as an impurity of 100 mass ppm or less. Moreover, the hydroxylamine whose content of each anion is 10 mass ppm or less can be obtained, and the hydroxylamine whose content of each anion is 1 mass ppm or less can also be obtained. Examples of the anion include sulfate ion, chloride ion, nitrate ion and the like derived from a salt of hydroxylamine as a raw material.

  In any of the above steps (1) to (4), when 3,4-dihydroxybenzoic acid is used, it is not necessary to remove and recover it, and it may be used as a storage stabilizer. In this case, the amount of 3,4-dihydroxybenzoic acid added as a storage stabilizer is set by adding the amount of 3,4-dihydroxybenzoic acid already present in the solution.

<Example>
Hereinafter, although it demonstrates more concretely using an Example and a comparative example, this invention is not limited to these Examples.
(Examples 1-3)
3,4-dihydroxybenzoic acid as a storage stabilizer was added to a 50 mass% hydroxylamine aqueous solution having an Fe concentration of 0.01 mass ppm or less so as to have a predetermined concentration with respect to the 50 mass% hydroxylamine aqueous solution.

100 g of the 50 mass% hydroxylamine aqueous solution prepared above was filled in a PFA 500 ml lidded container, covered, and placed in a 50 ° C. thermostat.
The coloring of the hydroxylamine aqueous solution after 30 days was visually confirmed. Then, the concentration of hydroxylamine was measured by hydrochloric acid titration, and the decomposition rate of hydroxylamine was determined from the following formula.

Hydroxylamine decomposition rate (%) = (50−A) / 50 × 100
A = hydroxylamine concentration after 30 days (mass%)
The results are summarized in Table 1.
(Comparative Examples 1-6)
As a storage stabilizer, it carried out like Examples 1-3 except having added the storage stabilizer of Table 1 instead of 3,4-dihydroxybenzoic acid.

  The results are summarized in Table 1.

From the above Examples and Comparative Examples, it can be seen that 3,4-dihydroxybenzoic acid is effective in stabilizing the hydroxylamine aqueous solution as a storage stabilizer and no coloring is observed.
(Examples 4 to 12)
3,4-dihydroxybenzoic acid as a storage stabilizer was added to a 50 mass% hydroxylamine aqueous solution having an Fe concentration of 0.01 mass ppm or less so as to have a predetermined concentration with respect to the 50 mass% hydroxylamine aqueous solution. Furthermore, the antioxidant was similarly added with respect to 50 mass% hydroxylamine aqueous solution so that it might become a predetermined density | concentration.

100 g of the 50 mass% hydroxylamine aqueous solution prepared above was filled in a PFA 500 ml lidded container, covered, and placed in a 50 ° C. thermostat.
The coloring of the hydroxylamine aqueous solution after 30 days was visually confirmed. Then, the concentration of hydroxylamine was measured by hydrochloric acid titration, and the decomposition rate of hydroxylamine was determined from the following formula.

Hydroxylamine decomposition rate (%) = (50−A) / 50 × 100
A = hydroxylamine concentration after 30 days (mass%)
The results are summarized in Table 2.

From the above Examples, it can be seen that addition of an antioxidant to 3,4-dihydroxybenzoic acid is more effective in stabilizing the hydroxylamine aqueous solution and no coloring is observed.
(Examples 13 to 15)
3,4-dihydroxybenzoic acid as a storage stabilizer was added to a 50 mass% hydroxylamine aqueous solution having an Fe concentration of 0.01 mass ppm or less so as to have a predetermined concentration with respect to the 50 mass% hydroxylamine aqueous solution.

20 g of the 50 mass% hydroxylamine aqueous solution prepared above was filled in a 500 ml lidded container made of PFA.
To this, a 1,000 mg / L standard solution of Fe (III) was added to a 50% by mass hydroxylamine aqueous solution so that the Fe concentration was a predetermined concentration, and then a lid was placed on a 50 ° C. constant temperature bath. installed.

After 7 days, the concentration of hydroxylamine was measured by hydrochloric acid titration, and the decomposition rate of hydroxylamine was determined from the following formula.
Hydroxylamine decomposition rate (%) = (50−B) / 50 × 100
B = hydroxylamine concentration after 7 days (mass%)
The results are summarized in Table 3.
(Comparative Examples 7-12)
As storage stabilizer, it carried out similarly to Examples 13-15 except having added the storage stabilizer of Table 3 instead of 3, 4- dihydroxy benzoic acid (however, Comparative Example 7 had no storage stabilizer, Fe (III) Performed at a concentration of 1 ppm by mass) .

  The results are summarized in Table 3.

From the above examples and comparative examples, 3,4-dihydroxybenzoic acid is used as a storage stabilizer.
It can be seen that there is an effect in stabilizing the hydroxylamine aqueous solution in the presence of Fe.
(Examples 16 to 24)
3,4-dihydroxybenzoic acid as a storage stabilizer was added to a 50 mass% hydroxylamine aqueous solution having an Fe concentration of 0.01 mass ppm or less so as to have a predetermined concentration with respect to the 50 mass% hydroxylamine aqueous solution. Furthermore, the antioxidant was similarly added with respect to 50 mass% hydroxylamine aqueous solution so that it might become a predetermined density | concentration.

20 g of the 50 mass% hydroxylamine aqueous solution prepared above was filled in a 500 ml lidded container made of PFA.
To this, a 1,000 mg / L standard solution of Fe (III) was added to a 50% by mass hydroxylamine aqueous solution so that the Fe concentration was a predetermined concentration, and then a lid was placed on a 50 ° C. constant temperature bath. installed.

After 7 days, the concentration of hydroxylamine was measured by hydrochloric acid titration, and the decomposition rate of hydroxylamine was determined from the following formula.
Hydroxylamine decomposition rate (%) = (50−B) / 50 × 100
B = hydroxylamine concentration after 7 days (mass%)
The results are summarized in Table 4.

  From the above Examples, it can be seen that the addition of an antioxidant to 3,4-dihydroxybenzoic acid is more effective in stabilizing the hydroxylamine aqueous solution in the presence of Fe.

  According to the present invention, a hydroxylamine solution can be stabilized and a stabilized hydroxylamine solution can be obtained. In particular, according to the present invention, the stability of hydroxyamine is significantly improved at high temperatures, high concentrations and / or in the presence of metal impurities, thereby expanding the scope of application of hydroxyamine to various uses.

Claims (9)

  A method for stabilizing hydroxylamine, comprising adding 3,4-dihydroxybenzoic acid as a storage stabilizer to a hydroxylamine solution.   The method for stabilizing hydroxylamine according to claim 1, wherein an antioxidant is further added. The antioxidant, alcohols, phenol derivatives, ethylenic double bond-containing compounds, acetylenic triple bond-containing compounds, nitrile compounds, sulfur-containing organic compound, at least selected from the group consisting of nitrogen-containing organic compounds and phosphorus-containing organic compounds The method for stabilizing hydroxylamine according to claim 2, which is a single compound. The sulfur-containing organic compound is phenothiazine, 2,2′-dibenzothiazolyl disulfide, 2-mercaptobenzothiazole, 2-mercaptobenzimidazole, 2-mercaptobenzothiazole sodium salt, thiouric acid, bismuthiol, distearyl-3, 3′-thiodipropionate, dilauryl-3,3′-thiodipropionate, dimyristyl-3,3′-thiodipropionate, cysteine, cystine, dimercaptosuccinic acid, 2-aminoethanethiol, toluene-3 , 4-dithiol and furfuryl mercaptan,
The nitrogen-containing organic compound is 1,1-diphenyl-2-picryl-hydrazyl, N-nitroso-diphenylamine, 4-nitrosodiphenylamine, 2-methyl-2-nitrosopropane, α-phenyl (t-butyl) nitrone, N -Phenyl-N'-i-propylphenylenediamine, 5,5-dimethyl-N-phenyl-N'-i-propylphenylenediamine, 1-nitroso-2-naphthol, 2-nitroso-1-naphthol, nitrosobenzene and At least one selected from diphenylamine,
The phosphorus-containing organic compound is triethylphosphine, triphenylphosphine, trimethylphosphite, triethylphosphite, triphenylphosphite, distearylpentaerythritol diphosphite, diphenyl-i-octylphosphite and tris (2,4 The method for stabilizing hydroxylamine according to claim 3, which is at least one selected from among (-di-t-butylphenyl) phosphite.   A stabilized hydroxylamine solution comprising hydroxylamine and 3,4-dihydroxybenzoic acid. 6. The stabilized hydroxylamine solution of claim 5 , further comprising an antioxidant. The antioxidant, alcohols, phenol derivatives, ethylenic double bond-containing compounds, acetylenic triple bond-containing compounds, nitrile compounds, sulfur-containing organic compound, at least selected from the group consisting of nitrogen-containing organic compounds and phosphorus-containing organic compounds The stabilized hydroxylamine solution of claim 6 which is a compound. The sulfur-containing organic compound is phenothiazine, 2,2′-dibenzothiazolyl disulfide, 2-mercaptobenzothiazole, 2-mercaptobenzimidazole, 2-mercaptobenzothiazole sodium salt, thiouric acid, bismuthiol, distearyl-3, 3′-thiodipropionate, dilauryl-3,3′-thiodipropionate, dimyristyl-3,3′-thiodipropionate, cysteine, cystine, dimercaptosuccinic acid, 2-aminoethanethiol, toluene-3 , 4-dithiol and furfuryl mercaptan,
The nitrogen-containing organic compound is 1,1-diphenyl-2-picryl-hydrazyl, N-nitroso-diphenylamine, 4-nitrosodiphenylamine, 2-methyl-2-nitrosopropane, α-phenyl (t-butyl) nitrone, N -Phenyl-N'-i-propylphenylenediamine, 5,5-dimethyl-N-phenyl-N'-i-propylphenylenediamine, 1-nitroso-2-naphthol, 2-nitroso-1-naphthol, nitrosobenzene and At least one selected from diphenylamine,
The phosphorus-containing organic compound is triethylphosphine, triphenylphosphine, trimethylphosphite, triethylphosphite, triphenylphosphite, distearylpentaerythritol diphosphite, diphenyl-i-octylphosphite and tris (2,4 The stabilized hydroxylamine solution according to claim 7, which is at least one member selected from among (di-t-butylphenyl) phosphite.   A hydroxylamine stabilizer comprising 3,4-dihydroxybenzoic acid as an active ingredient.