DK162761B

DK162761B - STABILIZED SOLUTIONS OF HYDROXYLAMINE OR SALTS THEREOF METHOD OF PREPARING THESE

Info

Publication number: DK162761B
Application number: DK570284A
Authority: DK
Inventors: Otto-Alfred Grosskinsky; Elmar Frommer; Josef Ritz; Erwin Thomas; Franz-Josef Weiss
Original assignee: Basf Ag
Priority date: 1983-12-02
Filing date: 1984-11-30
Publication date: 1991-12-09
Also published as: DK162761C; JPS60131813A; DK570284D0; DE3460708D1; DK570284A; EP0146016A1; DE3343599A1; EP0146016B1

Description

DK 162761 BDK 162761 B

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Opfindelsen angår stabiliserede opløsninger af hydro-xylamin eller dennes salte i vand eller alkoholer samt en fremgangsmåde til fremstilling af disse.The invention relates to stabilized solutions of hydroxylamine or its salts in water or alcohols and to a process for their preparation.

Opløsninger af hydroxylammoniumsalte sønderdeles langsomt 5 ved stuetemperatur og hurtigere ved forhøjet temperatur. Dette gælder i højere grad for opløsninger af fri hydroxylamin. Det har ikke manglet på forsøg på stabilisering af opløsninger af hydroxylamin og salte af denne med henblik på tilvejebringelse af forbedrede opbeva-10 ringsegenskaber. Ifølge US PS 3 544 270 anvendes urinsto f der i vater som stabiliseringsmiddel. Fra US PS 3 480 391 er det kendt, at amidoximer er egnede som stabilisatorer., og i US PS 3 480 392 anbefales hydroxam-syrer til samme formål. Endelig er anvendelse af chelat-15 dannende midler, såsom natriumsaltet af ethylendiamin-tetraeddikesyre, som stabiliseringsmiddel kendt fra US PS 3 145 082. Det er imidlertid ønskeligt at tilvejebringe stabiliseringsmidler, der er mere effektive end de hidtil anvendte.Solutions of hydroxylammonium salts decompose slowly at room temperature and more rapidly at elevated temperature. This is more true for solutions of free hydroxylamine. It has not been lacking in attempts to stabilize solutions of hydroxylamine and its salts to provide improved storage properties. According to US PS 3 544 270, urea is used in water as a stabilizing agent. It is known from US PS 3 480 391 that amidoximes are suitable as stabilizers and in US PS 3 480 392 hydroxamic acids are recommended for the same purpose. Finally, the use of chelating agents, such as the sodium salt of ethylenediamine tetraacetic acid, as a stabilizing agent is known from US PS 3 145 082. However, it is desirable to provide stabilizing agents which are more effective than those previously used.

20 Den til grund for opfindelsen liggende opgave går ud på at tilvejebringe stabiliserede opløsninger af hydroxylamin eller dennes salte, der er stabile gennem et længere tidsrum og især udmærker sig ved en minimal sønderdeling af fri hydroxylamin.The object of the invention is to provide stabilized solutions of hydroxylamine or its salts which are stable over a longer period of time and are particularly distinguished by a minimal decomposition of free hydroxylamine.

25 Denne opgave løses ifølge opfindelsen ved stabiliserede opløsninger af hydroxylamin eller dennes salte i vand eller alkoholer, som er ejendommelige ved, at de indeholder flavaner med formlen K2 i, 2This object is solved according to the invention by stabilized solutions of hydroxylamine or its salts in water or alcohols, which are characterized in that they contain flavanes of formula K2 in, 2

DK 162761 BDK 162761 B

hvori R^ - hver betyder et hydrogenatom, en hydroxyl-gruppe, en (C^-C^)alkoxygruppe eller en (C^-C^)acyloxy-gruppe, idet mindst én substituent er en hydroxylgruppe.wherein R 1 - each means a hydrogen atom, a hydroxyl group, a (C 1 -C 4) alkoxy group or a (C 1 -C 2) acyloxy group, at least one substituent being a hydroxyl group.

Opfindelsen angår endvidere en fremgangsmåde til frem-5 stilling af stabiliserede opløsninger af hydroxylamin eller dennes salte ved tilsætning af stabilisatorer, som er ejendommelig ved, at man fjerner det i opløst form tilstedeværende molekylære oxygen fra de opløsninger, som ønskes stabiliseret, ved behandling med 10 nitrogen, som ikke indeholder molekylær oxygen, og derpå tilsætter flavaner, der er substitueret med mindst én hydroxylgruppe.The invention further relates to a process for the preparation of stabilized solutions of hydroxylamine or its salts by the addition of stabilizers which are characterized by removing the molecular oxygen present in the dissolved form from the solutions desired to be stabilized by treatment with nitrogen which does not contain molecular oxygen, and then adds flavanes substituted by at least one hydroxyl group.

De ifølge opfindelsen stabiliserede opløsninger af hydroxylamin eller dennes salte udviser den fordel, at de 15 er stabile gennem længere tid end de hidtil kendte stabi liserede opløsninger. Især er sønderdelingen af fri hydroxylamin reduceret til et minimum.The stabilized solutions of hydroxylamine or its salts according to the invention have the advantage of being stable over a longer period of time than the previously known stabilized solutions. In particular, the decomposition of free hydroxylamine is reduced to a minimum.

Ved fremstillingen af opløsningerne ifølge opfindelsen går man ud fra opløsninger af hydroxylamin eller dennes 20 salte i vand eller alkoholer, f.eks. alkanoler med 1 - 4 carbonatomer. Egnede salte af hydroxylamin er f.eks. salte med stærke mineralsyrer, såsom svovlsyre, salpetersyre og saltsyre, eller med fede syrer, f.eks. eddikesyre eller propionsyre. På grund af de forskellige oplø-25 seligheder foreligger hydroxylamin fortrinsvis opløst i vand eller alkoholer, medens saltene fortrinsvis foreligger som vandige opløsninger. Indholdet af hydroxylamin eller dennes salte udgør som regel fra 10 til 70 vægt-?o. Udgangsopløsningerne har som regel en pH-værdi 30 på 8 - 11. Særligt foretrukne er opløsninger af hydroxyl amin i vand.In the preparation of the solutions according to the invention, solutions of hydroxylamine or its salts in water or alcohols are used, e.g. alkanols having 1-4 carbon atoms. Suitable hydroxylamine salts are e.g. salts with strong mineral acids such as sulfuric acid, nitric acid and hydrochloric acid, or with fatty acids, e.g. acetic or propionic acid. Due to the various solubilities, hydroxylamine is preferably dissolved in water or alcohols, while the salts are preferably present as aqueous solutions. The content of hydroxylamine or its salts usually ranges from 10 to 70% by weight. The starting solutions usually have a pH value of 8 - 11. Particularly preferred are solutions of hydroxyl amine in water.

Som stabilisatorer anvendes flavaner indeholdende mindst 1, fortrinsvis mindst 3 hydroxylgrupper i molekylet.As stabilizers, flavanes containing at least 1, preferably at least 3 hydroxyl groups, are used in the molecule.

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Foretrukne flavaner er forbindelser med formlen hvori R* - R ^ hver betyder et hydrogenatom, en hydroxy 1-gruppe, en (C^-C^)alkoxygruppe eller en (-C^)acyloxy-gruppe, idet mindst én substituent er en hydroxylgruppe.Preferred flavanes are compounds of the formula wherein R 1 - R 2 each means a hydrogen atom, a hydroxy 1 group, a (C 1 -C 4) alkoxy group or a (-C 2) acyloxy group, wherein at least one substituent is a hydroxyl group .

5 Særligt foretrukne flavaner med formel (I) er forbin delser, hvori R1 - R° hver betyder et hydrogenatom, en hydroxylgruppe eller en methoxygruppe, idet mindst 3 substituenter er hydroxylgrupper. De hydroxysubsti-tuerede flavaner kan også foreligge som glycosider.Particularly preferred flavanes of formula (I) are compounds wherein R 1 - R 2 each represent a hydrogen atom, a hydroxyl group or a methoxy group, with at least 3 substituents being hydroxyl groups. The hydroxy-substituted flavanes may also be present as glycosides.

10 Egnede flavaner er kendt fra Angewandte Chemie _68 ( 1956 ), side 110 og 111.Suitable flavors are known from Angewandte Chemie _68 (1956), pages 110 and 111.

De hydroxysubstituerede flavaner anvendes fortrinsvis i en mængde fra 0,005 til 1 vægt-%, især fra 0,01 til 0,1 vægt-%, beregnet på den opløsning, som ønskes stabili-15 seret. Det har endvidere vist sig fordelagtigt at medan vende polyhydroxybenzener, især pyrogallol. Polyhydroxy-benzenerne tilsættes fortrinsvis i mængder fra 0,005 til 0,1 vægt-%, beregnet på den opløsning, som ønskes stabiliseret. Det er bemærkelsesværdigt, at der tilveje-20 bringes en synergistisk virkning ved kombineret anvendel se af hydroxylsubstituerede flavaner og polyhydroxybenzener .The hydroxy-substituted flavanes are preferably used in an amount of from 0.005 to 1% by weight, in particular from 0.01 to 0.1% by weight, based on the solution desired to be stabilized. Furthermore, it has been found advantageous to reverse polyhydroxybenzenes, especially pyrogallol. The polyhydroxybenzenes are preferably added in amounts of 0.005 to 0.1% by weight, based on the solution desired to be stabilized. It is noteworthy that a synergistic effect is produced by the combined use of hydroxyl-substituted flavanes and polyhydroxybenzenes.

Stabiliserede opløsninger af hydroxylamin eller dennes ' salte i vand eller alkoholer fremstilles ifølge opfin- 25 delsen på følgende måde: først fortrænges det i opløst form tilstedeværende molekylære oxygen fra de opløsninger, som ønskes stabiliseret, ved behandling med nitrogen, som ikke indeholder molekylær oxygen. Denne behand-Stabilized solutions of hydroxylamine or its salts in water or alcohols are prepared according to the invention in the following way: first, the dissolved molecular oxygen present in the solutions which are desired to be stabilized is displaced by treatment with nitrogen which does not contain molecular oxygen. This treatment

DK 162761BDK 162761B

4 ling kan f.eks. gennemføres ved gennemledning af oxygenfri nitrogen, f.eks. i 5 - 10 minutter. Det anvendte nitrogen indeholder fortrinsvis mindre end 2 ppm 0^·4 ling can e.g. is carried out by passing oxygen-free nitrogen, e.g. for 5 - 10 minutes. The nitrogen used preferably contains less than 2 ppm O

Derefter tilsættes hydroxysubstitueret flavan samt even-5 tuelt polyhydroxybenzener, og disse opløses i den opløs ning, som ønskes stabiliseret. Dette sker fortrinsvis ved en temperatur på 5 - 40 °C. Det er også muligt at tilsætte stabilisatorerne i opløst tilstand, f.eks. opløst i alkanoler med 1-4 carbonatomer.Thereafter, hydroxy-substituted flavan and optionally polyhydroxybenzenes are added and dissolved in the solution which is desired to be stabilized. This is preferably done at a temperature of 5 - 40 ° C. It is also possible to add the stabilizers in the dissolved state, e.g. dissolved in alkanols having 1-4 carbon atoms.

10 Det er klart, at det er fordelagtigt at undgå kontamine ring af opløsningerne med tungmetaller, især kobbereller ædelmetaller, da disse katalyserer sønderdelingen af hydroxylamin. Det er endvidere fordelagtigt at udelukke energirige stråler ved anvendelse af passende 15 farvede glasbeholdere. Endelig er det fordelagtigt at opbevare de stabiliserede opløsninger ved temperaturer mindre end 40 °C, f.eks. ved temperaturer på 5 - 20 °C.Obviously, it is advantageous to avoid contamination of the solutions with heavy metals, especially copper or precious metals, as these catalyze the decomposition of hydroxylamine. Furthermore, it is advantageous to exclude energy-rich rays by using suitable colored glass containers. Finally, it is advantageous to store the stabilized solutions at temperatures less than 40 ° C, e.g. at temperatures of 5 - 20 ° C.

De stabiliserede opløsninger af hydroxylamin eller dennes 20 salte er egnet til fremstilling af oximer. 1 det følgende belyses opfindelsen nærmere ved hjælp af et eksempel.The stabilized solutions of hydroxylamine or its salts are suitable for the production of oxymers. In the following, the invention is further illustrated by way of example.

EKSEMPELEXAMPLE

En vandig opløsning af hydroxylamin blev behandlet med 25 oxygenfri nitrogen i 10 minutter ved 20 °C, hvorefter stabilisatoren blev tilsat. Hydroxylaminkoncentration, tilsat mængde og art af stabilisatoren samt de af tid og temperatur afhængige resultater fremgår af nedenstående tabel.An aqueous solution of hydroxylamine was treated with 25 oxygen-free nitrogen for 10 minutes at 20 ° C, after which the stabilizer was added. Hydroxylamine concentration, amount and type of stabilizer added, as well as the time and temperature dependent results are shown in the table below.

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TABELTABLE

Stabilisator *CStabilizer * C

50 ppm d-Catechin 5 0 743 1198 timer50 ppm d-Catechin 5 0 743 1198 hours

110,88 110,72 110,55 g/1 NH20H110.88 110.72 110.55 g / l NH 2 OH

50 ppm d-Catechin 20 0 404 1195 timer50 ppm d-Catechin 20 0 404 1195 hours

110.25 109,63 109,49 g/1 NH20H110.25 109.63 109.49 g / l NH 2 OH

50 ppm d-Catechin 40 0 359 1194 timer 110.25 109,79 108,57 g/1 NH2oH 150 ppm d-Catechin 40 0 359 1194 hours 110.25 109.79 108.57 g / l NH

Claims

1. Stabilized solutions of hydroxylamine or its salts in water or alcohols, characterized in that they contain as a stabilizing agent flavanes of formula R 2 R 5 wherein R 2 - each means a hydrogen atom, a hydroxyl group, a (C alkoxy group or a (C 1 -C 4) acyloxy group, at least one substituent being a hydroxy group.

Stabilized solutions according to claim 1, characterized in that they contain flavanes of the formula as set forth in claim 1, wherein - R 1 is each a hydrogen atom, a hydroxy group or a methoxy group, at least 3 substituents being hydroxyl groups.

Stabilized solutions according to claims 1 and 2, characterized in that they contain 0.005 - 1 weight-15 flavans of formula (I), calculated on the solution desired to be stabilized.

Stabilized solutions according to claims 1-3, characterized in that they additionally contain pyrogallol.

Process for the preparation of stabilized solutions of hydroxylamine or its salts in water or alcohols by the addition of stabilizers, characterized in that the molecular oxygen present in the dissolved form is removed from the solutions desired to be stabilized by treatment with nitrogen which does not contain molecular oxygen and then adds hydroxy-substituted flavanes.