DK152116B - PROCEDURE FOR REDUCING NITROSAMINE CONTENT IN DINITROANILINES - Google Patents
PROCEDURE FOR REDUCING NITROSAMINE CONTENT IN DINITROANILINES Download PDFInfo
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- C07C211/00—Compounds containing amino groups bound to a carbon skeleton
- C07C211/43—Compounds containing amino groups bound to a carbon skeleton having amino groups bound to carbon atoms of six-membered aromatic rings of the carbon skeleton
- C07C211/44—Compounds containing amino groups bound to a carbon skeleton having amino groups bound to carbon atoms of six-membered aromatic rings of the carbon skeleton having amino groups bound to only one six-membered aromatic ring
- C07C211/52—Compounds containing amino groups bound to a carbon skeleton having amino groups bound to carbon atoms of six-membered aromatic rings of the carbon skeleton having amino groups bound to only one six-membered aromatic ring the carbon skeleton being further substituted by halogen atoms or by nitro or nitroso groups
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- C07C201/06—Preparation of nitro compounds
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- C07C205/07—Compounds containing nitro groups bound to a carbon skeleton the carbon skeleton being further substituted by halogen atoms
- C07C205/11—Compounds containing nitro groups bound to a carbon skeleton the carbon skeleton being further substituted by halogen atoms having nitro groups bound to carbon atoms of six-membered aromatic rings
- C07C205/12—Compounds containing nitro groups bound to a carbon skeleton the carbon skeleton being further substituted by halogen atoms having nitro groups bound to carbon atoms of six-membered aromatic rings the six-membered aromatic ring or a condensed ring system containing that ring being substituted by halogen atoms
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- C07—ORGANIC CHEMISTRY
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- C07C209/00—Preparation of compounds containing amino groups bound to a carbon skeleton
- C07C209/04—Preparation of compounds containing amino groups bound to a carbon skeleton by substitution of functional groups by amino groups
- C07C209/06—Preparation of compounds containing amino groups bound to a carbon skeleton by substitution of functional groups by amino groups by substitution of halogen atoms
- C07C209/10—Preparation of compounds containing amino groups bound to a carbon skeleton by substitution of functional groups by amino groups by substitution of halogen atoms with formation of amino groups bound to carbon atoms of six-membered aromatic rings or from amines having nitrogen atoms bound to carbon atoms of six-membered aromatic rings
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- C07C209/30—Preparation of compounds containing amino groups bound to a carbon skeleton by reduction of nitrogen-to-oxygen or nitrogen-to-nitrogen bonds
- C07C209/32—Preparation of compounds containing amino groups bound to a carbon skeleton by reduction of nitrogen-to-oxygen or nitrogen-to-nitrogen bonds by reduction of nitro groups
- C07C209/36—Preparation of compounds containing amino groups bound to a carbon skeleton by reduction of nitrogen-to-oxygen or nitrogen-to-nitrogen bonds by reduction of nitro groups by reduction of nitro groups bound to carbon atoms of six-membered aromatic rings in presence of hydrogen-containing gases and a catalyst
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- C07—ORGANIC CHEMISTRY
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- C07C211/43—Compounds containing amino groups bound to a carbon skeleton having amino groups bound to carbon atoms of six-membered aromatic rings of the carbon skeleton
- C07C211/44—Compounds containing amino groups bound to a carbon skeleton having amino groups bound to carbon atoms of six-membered aromatic rings of the carbon skeleton having amino groups bound to only one six-membered aromatic ring
- C07C211/49—Compounds containing amino groups bound to a carbon skeleton having amino groups bound to carbon atoms of six-membered aromatic rings of the carbon skeleton having amino groups bound to only one six-membered aromatic ring having at least two amino groups bound to the carbon skeleton
- C07C211/50—Compounds containing amino groups bound to a carbon skeleton having amino groups bound to carbon atoms of six-membered aromatic rings of the carbon skeleton having amino groups bound to only one six-membered aromatic ring having at least two amino groups bound to the carbon skeleton with at least two amino groups bound to carbon atoms of six-membered aromatic rings of the carbon skeleton
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Description
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Den foreliggende opfindelse angår en fremgangsmåde til formindskelse af nitrosaminindholdet i dinitroaniliner.The present invention relates to a process for reducing the nitrosamine content of dinitroanilines.
I Russian Chem. Rev., 4£ (1), 34-50 (1971) (eng.), gøres der generelt rede for kemien af aliphatiske N-nitrosaminer. Blandt andre emner beskrives reaktiviteten af nitrosaminer. Artiklen omtaler reaktionen af brom og svovlsyre med nitrosaminer. En artikel i Lieb. Ann., 151, 366 (1.869), beskriver, at nitrosodibenzylamin opløstes i brom. Produkterne var mono- og dibromerede dibenzylaminer. Det angives, at hydrogenbromid er et effektivt denitroseringsmiddel (Chem. Abst. , (5, 2434-2435 (1912), og Arzneimittel Forsch., 20^, 1513 (1970).In Russian Chem. Rev., £ 4 (1), 34-50 (1971) (eng.), Generally explains the chemistry of aliphatic N-nitrosamines. Among other topics, the reactivity of nitrosamines is described. The article discusses the reaction of bromine and sulfuric acid with nitrosamines. An article in Lieb. Ann., 151, 366 (1,869), disclose that nitrosodibenzylamine dissolved in bromine. The products were mono- and dibromized dibenzylamines. It is stated that hydrogen bromide is an effective denitrifying agent (Chem. Abst., (5, 2434-2435 (1912), and Arzneimittel Forsch., 20, 1513 (1970).
Klassen af dinitroanilinforbindelser indbefatter talrige kommercielle herbicider. I den senere tid er der udvikThe class of dinitroaniline compounds includes numerous commercial herbicides. Lately there has been development
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2 let et hidtil ukendt analytisk apparatur, kendt som et termisk energianalyseapparat (TEA) [J. Chromatogr., 107 (1975), 351, og de deri citerede referencer, samt "N-Nitroso Compounds in the Environment", IARC Scientific Publication nr. 9 (International Agency for Research on Cancer, Lyon, 1974), side 40].2 readily a novel analytical apparatus known as a thermal energy analyzer (TEA) [J. Chromatogr., 107 (1975), 351, and the references cited therein, as well as "N-Nitroso Compounds in the Environment", IARC Scientific Publication No. 9 (International Agency for Research on Cancer, Lyon, 1974), page 40].
TEA analyserer specifikt for nitroso- (-NO)-gruppen, og det er i stand til at påvise nitrosogruppen i så lave koncentrationer som 0,02 ppm - meget lavere end tidligere kendt analyseteknik. En analyse af forskellige dinitroaniliner med TEA afslører, at nogle af dinitroanilinerne indeholder meget små mængder nitrosaminer. Tilstedeværelsen af endog en meget ringe mængde nitrosamin betragtes som uønskelig, fordi visse af nitrosaminerne har vist sig at være carcinogene ved dyr.TEA specifically analyzes for the nitroso (-NO) group, and it is able to detect the nitroso group at concentrations as low as 0.02 ppm - much lower than previously known assay techniques. An analysis of various dinitroanilines with TEA reveals that some of the dinitroanilines contain very small amounts of nitrosamines. The presence of even a very small amount of nitrosamine is considered undesirable because some of the nitrosamines have been found to be carcinogenic in animals.
Fjernelsen af nitrosaminer fra dinitroaniliner, som er fremstillet kommercielt med henblik på anvendelse som herbicider, frembyder imidlertid specielle problemer, fordi der på den ene side er tale om meget store kvantiteter, som skal behandles, medens der på den anden side er tale om, at nitrosaminindholdet skal formindskes fra meget lavt til yderst lavt. Forsøg har vist, at mange kendte nitrosaminfjernelsesreagenser, som er effektive ved højere nitrosaminkoncentrationer, er aldeles ineffektive ved de lave koncentrationer, som dinitroanilinherbicidfremstilling opererer med. Dertil kommer, at mange af disse reagenser skal anvendes under betingelser, som ikke kan overføres til industriel målestok, f.eks. af økonomiske grunde.However, the removal of nitrosamines from dinitroanilines commercially prepared for use as herbicides presents special problems because, on the one hand, they are very large quantities that must be treated, while on the other hand, the nitrosamine content must be reduced from very low to extremely low. Studies have shown that many known nitrosamine removal reagents which are effective at higher nitrosamine concentrations are completely ineffective at the low concentrations at which dinitroaniline herbicide production operates. In addition, many of these reagents must be used under conditions which cannot be transferred to an industrial scale, e.g. for financial reasons.
Formålet med den foreliggende opfindelse er derfor at tilvejebringe en fremgangsmåde til formindskelse af nitrosaminindholdet i dinitroaniliner, og denne fremgangsmåde skal ydermere være effektiv ved de ovenfor omtalte, specielle forhold i forbindelse med dinitroanilinherbicidfremstillingen. Fjernelse af nitrosaminerne fra disse herbicider anses for at være en ønskelig forsigtighedsforanstaltning ved beskyttelsen af mennesker og husdyrbestande mod en mulig kilde for dinitrosaminer.The object of the present invention is therefore to provide a process for reducing the nitrosamine content of dinitroanilines, and this method is further effective in the above-mentioned special conditions associated with dinitroaniline herbicide preparation. Removal of the nitrosamines from these herbicides is considered a desirable precaution in protecting humans and livestock from a possible source of dinitrosamines.
Den foreliggende opfindelse tilvejebringer en fremgangsmåde til formindskelse af nitrosaminindholdet i de nedenfor specifikt angivne dinitroaniliner, hvilken fremgangsmåde er ejendommelig ved, at det nitrosaminholdige dinitroanilin i fly 3The present invention provides a process for reducing the nitrosamine content of the dinitroanilines specifically specified below, which is characterized in that the nitrosamine-containing dinitroaniline in aircraft 3
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dende fase og ved en temperatur mellem stuetemperatur og 140°C bringes i kontakt med et reagens valgt blandt molekylært brom, molekylært chlor, N-bromsuccinimid, N-chlorsuccinimid, bromchlo-rid, pyridinperbromid og pyridiniumbromidperbromid, indtil koncentrationen af nitrosaminen er blevet formindsket.at that temperature and at a temperature between room temperature and 140 ° C are contacted with a reagent selected from molecular bromine, molecular chlorine, N-bromosuccinimide, N-chlorosuccinimide, bromochloride, pyridine perbromide and pyridinium bromide perbromide until the concentration of the nitrosamine has been reduced.
Dinitroaniliner, hvorpå den her omhandlede fremgangsmåde kan udøves (og deres generiske navne, hvor sådanne forefindes), er 1) 4-trifluormethyl-2,6-dinitro-N,N-di-n-propylanilin (triflur-alin), 2) 4-isopropyl-2,6-dinitro-N,N-di-n-propylanilin (isopropalin), 3) 4-trifluormethyl-2,6-dinitro-N-n-butyl-N-ethylanilin (bene-fin) , 4) trifluormethyl-2,6-dinitro-N-propyl-N-(2-chlorethyl)-anilin (fluchloralin), 5) 4-trifluormethyl-2,6-dinitro-N-propyl-N-(cyclopropylmethyl)--anilin (profluralin), 6) 4-trifluormethyl-2,6-dinitro-3-amino-N,N-diethylanilin (dinitramin), 7) 4-trifluormethyl-2,6-dinitro-3-chlor-N,N-diethylanilin (mellemprodukt til dinitramin) og 8) 4-methyl-2,6-dinitro-N,N-bis-(2-chlorethyl)-anilin.Dinitroanilines to which the present process may be practiced (and their generic names where available) are 1) 4-trifluoromethyl-2,6-dinitro-N, N-di-n-propylaniline (trifluramine), 2) 4-isopropyl-2,6-dinitro-N, N-di-n-propylaniline (isopropaline), 3) 4-trifluoromethyl-2,6-dinitro-Nn-butyl-N-ethylaniline (benzene), 4) trifluoromethyl-2,6-dinitro-N-propyl-N- (2-chloroethyl) -aniline (fluchloraline), 5) 4-trifluoromethyl-2,6-dinitro-N-propyl-N- (cyclopropylmethyl) -aniline ( (6) 4-trifluoromethyl-2,6-dinitro-3-amino-N, N-diethylaniline (dinitramine), 7) 4-trifluoromethyl-2,6-dinitro-3-chloro-N, N-diethylaniline ( intermediate for dinitramine) and 8) 4-methyl-2,6-dinitro-N, N-bis- (2-chloroethyl) -aniline.
Foretrukne dinitroaniliner, med hvilke den foreliggende opfindelse gennemføres, er trifluralin, isopropalin og benefin.Preferred dinitroanilines with which the present invention is carried out are trifluralin, isopropaline and benefin.
Generelt fremstilles dinitroanilinerne ved en reaktionsvej, for hvilken nedenstående er typisk for trifluralin.Generally, the dinitroanilines are prepared by a reaction pathway for which the following is typical of trifluralin.
• nr /*~~*\ π h®3- \ rr HaO \ /»—.-NOa CF3‘\ A01 H2SO4 / CF3~*\. .A01 ~W-7 CFa~\ AN(""C3H7)a HN(n-C3H,)2 •"-N02• nr / * ~~ * \ π h®3- \ rr HaO \ / »—.-NOa CF3 '\ A01 H2SO4 / CF3 ~ * \. .A01 ~ W-7 CFa ~ \ AN ("" C3H7) and HN (n-C3H, 2) "-N02
Det antages, at ringe mængder af nitrogenoxider, der er tilbage fra nitreringstrinet, reagerer med en del af aminen under amineringstrinet, hvilket frembringer ringe mængder nitrosamin, der kan forekomme i dinitroanilinslutproduktet. Derfor forventes en hvilken som helst nitrosamin-forurening at være nitrosoderivatet af den anvendte alkylamin. Det gisnes imidlertid, at der også kan dannes -yderst små mængder også af andre nitrosaminer.It is believed that small amounts of nitrogen oxides remaining from the nitration step react with a portion of the amine during the amination step, producing small amounts of nitrosamine that may be present in the dinitroanil end product. Therefore, any nitrosamine contamination is expected to be the nitroso derivative of the alkylamine used. However, it is believed that extremely small amounts of other nitrosamines can also be formed.
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Fjernelsen af nitrosaminer er ønskelig-, uanset disses identitet, og den her omhandlede fremgangsmåde opfylder dette formål.The removal of nitrosamines is desirable, regardless of their identity, and the process of the present invention fulfills this purpose.
Den mekanisme., hvorved den her omhandlede fremgangsmåde arbejder, er ikke kendt med sikkerhed. Det er imidlertid kendt, at nitrosaminen omdannes, "denitroseres", til en forbindelse, der Ikke indeholder nitrosamingruppen, og det menes, men er endnu ikke bevist, at der kan udvikles NOBr eller N0C1 som en del af denitroseringen.The mechanism by which this process works is not known with certainty. However, it is known that the nitrosamine is converted, "denitosed," into a compound that does not contain the nitrosamine group, and it is believed, but has not yet been proven, that NOBr or NOC1 can be developed as part of the denitrosation.
Den her omhandlede fremgangsmåde tilvejebringer en væsentlig reduktion i nitrosaminkoncentrationen, uanset begyndelsesmængden af nitrosamin. Fremgangsmåden er blevet gennemført med dinitroaniliner indeholdende fra så lidt som 10 ppm nitrosamin til så meget som adskillige tusinde ppm nitrosamin. Nitrosaminkoncentrationen reduceres almindeligvis til ca. en tiendedel af begyndelsesmængden eller derunder. I mange tilfælde reduceres nitrosaminkoncentrationen til under ca. 1 ppm.The process of the present invention provides a substantial reduction in the concentration of nitrosamine, irrespective of the initial amount of nitrosamine. The process has been carried out with dinitroanilines containing from as little as 10 ppm nitrosamine to as much as several thousand ppm nitrosamine. The nitrosamine concentration is generally reduced to about one-tenth of the initial amount or less. In many cases, the nitrosamine concentration is reduced to below approx. 1 ppm.
Den her omhandlede fremgangsmåde gennemføres i væskefase. Ved de dinitroaniliner, der smelter ved lavere temperaturer, såsom under 140°C, opnås denne fortrinsvis ved opvarmning af det nitros-aminholdige dinitroanilin til dets smeltetemperatur eller noget højere. Trifluralin smelter ved 54-55°C, og benefin smelter ved 65-66°C. Isopropalin smelter ved ca. 30°C, men på grund af mindre urenheder er det almindeligvis flydende ved stuetemperatur. Væskefase kan yderligere opnås ved opløsning af det nitrosaminholdige dinitroanilin i et opløsningsmiddel. Egnede opløsningsmidler indbefatter aliphatiske alkoholer, såsom methanol og ethanol, og halogenerede aliphatiske carbonhydrider, såsom chloroform, methylen-chlorid og carbontetrachlorid. Opløsningsmidler, der er yderst reaktive med molekylært brom eller chlor, er uegnede.The process of the present invention is carried out in liquid phase. For the dinitroanilines which melt at lower temperatures, such as below 140 ° C, this is preferably obtained by heating the nitrosamine-containing dinitroaniline to its melting temperature or slightly higher. Trifluralin melts at 54-55 ° C and benefin melts at 65-66 ° C. Isopropaline melts at approx. 30 ° C, but due to minor impurities it is usually liquid at room temperature. Liquid phase can be further obtained by dissolving the nitrosamine-containing dinitroaniline in a solvent. Suitable solvents include aliphatic alcohols such as methanol and ethanol, and halogenated aliphatic hydrocarbons such as chloroform, methylene chloride and carbon tetrachloride. Solvents that are highly reactive with molecular bromine or chlorine are unsuitable.
Molekylært brom og molekylært chlor er de mest egnede reagenser, og af disse er brom særlig foretrukket. N-Bromsuccin-imid, N-chlorsuccinimid, bromchlorid, pyridinperbromid og pyridi-niumbromidperbromid kan imidlertid også anvendes. Den mængde reagens, der skal anvendes, er ikke kritisk, sålænge mængden er tilstrækkelig til at reducere begyndelsesmængden af nitrosamin til en mindre mængde. Når der anvendes brom, er 0,02-2,0 g reagens pr.Molecular bromine and molecular chlorine are the most suitable reagents, and of these bromine is particularly preferred. However, N-bromosuccin imide, N-chlorosuccinimide, bromochloride, pyridine perbromide and pyridinium bromide perbromide may also be used. The amount of reagent to be used is not critical as long as the amount is sufficient to reduce the initial amount of nitrosamine to a smaller amount. When bromine is used, 0.02-2.0 g of reagent per
100 g dinitroanilin tilfredsstillende, 0,2 g reagens pr. 100 g di- 5100 g dinitroaniline satisfactory, 0.2 g reagent per ml. 100 g of di-5
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nitroanilin viser sig at være optimalt. Når der anvendes chlor, er 15-100 ml/min. chlorgas pr. 100 g dinitroanilin tilfredsstillende, og 35 ml/min. chlorgas pr. 100 g dinitroanilin viser sig at være optimalt. Når der anvendes N-bromsuccinimid, N-chlorsuccin-imid, bromchlorid, pyridinperbromid eller pyridiniumbromidperbromid, er mængder på 0,05-5,0 g reagens pr. 100 g dinitroanilin egnede. · Reaktionen gennemføres ved temperaturer fra stuetemperatur og til 140°C, og temperaturer på under 120°C foretrækkes på grund af den større risiko for sidereaktioner ved højere temperaturer. Når fremgangsmåden gennemføres uden opløsningsmiddel, gennemføres reaktionen ved temperaturer på over det specifikke dinitro-anilins smeltetemperatur. Når fremgangsmåden gennemføres med trifluranilin, isopropalin ogbenefin uden anvendelse af opløsningsmiddel, er der opnået gode resultater ved temperaturer på fra 70 til 90°C for alle reagenser undtagen chlor. Ved chlor foretrækkes temperaturer på 90-120°C. Reaktionen kan gennemføres ved atmosfæriske tryk eller ved forhøjede tryk.nitroaniline proves to be optimal. When chlorine is used, 15-100 ml / min. chlorine gas per 100 g dinitroaniline satisfactorily, and 35 ml / min. chlorine gas per 100 g dinitroaniline proves to be optimal. When N-bromosuccinimide, N-chlorosuccinimide, bromochloride, pyridine perbromide or pyridinium bromide perbromide are used, amounts of 0.05-5.0 g of reagent per liter are used. 100 g dinitroaniline are suitable. · The reaction is carried out at temperatures from room temperature to 140 ° C and temperatures below 120 ° C are preferred due to the higher risk of side reactions at higher temperatures. When the process is carried out without solvent, the reaction is carried out at temperatures above the melting temperature of the specific dinitro-aniline. When carried out with trifluraniline, isopropaline and benefin without the use of solvent, good results have been obtained at temperatures of 70 to 90 ° C for all reagents except chlorine. For chlorine, temperatures of 90-120 ° C are preferred. The reaction can be carried out at atmospheric pressure or at elevated pressure.
Den hastighed, hvormed den her omhandlede fremgangsmåde skrider frem, varierer med koncentrationen af nitrosaminen, temperaturen, reagenset, dets tilsætningshastighed og andre faktorer. Hverken tilstedeværelsen af vand alene eller tilstedeværelsen af vand ved en neutral eller sur pH-værdi er skadelig. Tilstedeværelsen af vand med en alkalisk pH-værdi er imidlertid ufordelagtig, således at der foretrækkes en pH-værdi på under 8, når der er en betydelig mængde vand til stede i reaktionsblandingen. Nitrosaminfjernelsens fremadskriden kan overvåges ved gaschromatografi eller ved TEA-analyse. Denitroseringen er almindeligvis endt på under 1 time. Tidsstudier af den her omhandlede fremgangsmåde har vist et tidligt fald i mængderne af nitrosamin, efterfulgt i nogle tilfælde af en let stigning i nitrosaminmængderne efter langvarig reaktionstid. Det menes, at en langvarig udsættelse af (1) dinitro-anilinet og (2) denitroseringsprodukterne for reaktionsbetingelserne kan resultere i yderligere nitrosamindannelse. Det er derfor ønskeligt at minimalisere reaktionstiderne.The rate at which the present process proceeds varies with the concentration of the nitrosamine, the temperature, the reagent, its rate of addition and other factors. Neither the presence of water alone nor the presence of water at a neutral or acidic pH is harmful. However, the presence of water with an alkaline pH is disadvantageous, so that a pH of less than 8 is preferred when a significant amount of water is present in the reaction mixture. The progress of nitrosamine removal can be monitored by gas chromatography or by TEA analysis. The denitrification usually ends in less than 1 hour. Time studies of the present process have shown an early decrease in the amounts of nitrosamine, followed in some cases by a slight increase in the amounts of nitrosamine after prolonged reaction time. It is believed that prolonged exposure of (1) the dinitro-aniline and (2) denitrosation products to the reaction conditions may result in further nitrosamine formation. Therefore, it is desirable to minimize the reaction times.
Når reaktionen gennemføres uden opløsningsmiddel, kræves der ingen oparbejdning. Hvis der ønskes oparbejdning, er denne konventionel og tager form af bobling af luft gennem reaktionsbian-When the reaction is carried out without solvent, no reprocessing is required. If reprocessing is desired, it is conventional and takes the form of bubbling of air through the reaction binder.
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dingen eller blæsning af luft over reaktionsblandingens overflade, efterfulgt af vask med carbonat.or blowing air over the surface of the reaction mixture, followed by washing with carbonate.
Nedenstående eksempler illustrerer den foreliggende opfindelse, og de vil sætte en fagmand i stand til at udøve opfindelsen.The following examples illustrate the present invention and will enable one skilled in the art to practice the invention.
Medmindre andet er angivet, sker bestemmelsen af nitrosaminkoncentrationen i nedenstående eksempler ved en gaschromatogra-fisk metode, der er følsom ned til ca. 0,5 ppm. En "ikke-påviselig" aflæsning (angivet som "I-P") anses for at repræsentere mindre end ca. 0,5 ppm nitrosamin. Der anvendes en Hewlett-Packard Model 5711A gaschromatograf, men metoden kan gennemføres med et hvilket som helst gaschromatografiapparatur, der er udstyret med en flammeioniseringsdetektor. Søjlen er en glasspiral, 1,2 m høj x 3,2 mm i diameter, der er fyldt med 3% "Carbowax 20M" på 0,125-0,149 mm "AW DMCS Chromosorb G", og der arbejdes ved 100°C. Efter eluering af nitrosaminspidsen opvarmes søjlen til 230°C, og den holdes ved denne temperatur i ca. 15 minutter. Strømningshastigheden for helium er 60 ml pr. minut. Der anvendes en standard med ca. samme koncentration af nitrosamin, som forventes af prøven. Såvel standard som prøve fremstilles i methylenchlorid.Unless otherwise indicated, the determination of the nitrosamine concentration in the examples below is carried out by a gas chromatographic method which is sensitive down to approx. 0.5 ppm. A "non-detectable" reading (designated as "I-P") is considered to represent less than approx. 0.5 ppm nitrosamine. A Hewlett-Packard Model 5711A gas chromatograph is used, but the method can be carried out with any gas chromatography apparatus equipped with a flame ionization detector. The column is a glass coil, 1.2 m high x 3.2 mm in diameter, filled with 3% "Carbowax 20M" of 0.125-0.1149 mm "AW DMCS Chromosorb G" and is operated at 100 ° C. After eluting the nitrosamine peak, the column is heated to 230 ° C and maintained at this temperature for approx. 15 minutes. The flow rate for helium is 60 ml. minute. A standard of approx. the same concentration of nitrosamine expected from the sample. Both standard and sample are prepared in methylene chloride.
I de eksempler, der anvender TEA-analyse, er dette angivet. Analyser ved denne metode gennemføres ved praktisk taget samme fremgangsmåder, som er beskrevet i J. Chromatogr., 109 (1975), 271. I den foreliggende opfindelses sammenhæng anses denne metode for at være følsom over for nitrosaminkoncentrationer, der er så lave som 0,05 ppm. Når ΤΞΑ-analysen af de nedenfor angivne prøver ikke viser noget nitrosamin, angives den som "I-P".In the examples using TEA analysis, this is indicated. Assays by this method are carried out by practically the same procedures described in J. Chromatogr., 109 (1975), 271. In the context of the present invention, this method is considered to be sensitive to nitrosamine concentrations as low as 0. 05 ppm. When the ΤΞΑ analysis of the samples listed below shows no nitrosamine, it is indicated as "I-P".
Eksempel 1Example 1
Nitrosaminfjernelse fra trifluralin, bromNitrosamine removal from trifluralin, bromine
En portion på 30 g fra et parti trifluralin med et gennemsnitsindhold på 68 ppm nitrosamin smeltes, og der tilsættes 0,2 g (ca. 10 dråber) brom. Blandingen opvarmes til 70°C og holdes på denne temperatur i 30 minutter under omrøring. En prøve analyseres for nitrosamin. Der kan ikke påvises noget.A 30 g portion of a portion of trifluralin with an average content of 68 ppm nitrosamine is melted and 0.2 g (about 10 drops) of bromine is added. The mixture is heated to 70 ° C and kept at this temperature for 30 minutes with stirring. A sample is analyzed for nitrosamine. Nothing can be detected.
DK 152116BDK 152116B
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Eksempel 2Example 2
Nitrosaminfjernelse fra trifluralin, mindre mængde bromNitrosamine removal from trifluralin, less amount of bromine
Fremgangsmåden fra eksempel 1 gentages med den undtagelse, at der kun tilsættes 2 dråber (0,04 g) brom. Ved gaschromatografi påvises der intet nitrosamin. TEA-analyse viser 0,03 ppm nitrosamin.The procedure of Example 1 is repeated except that only 2 drops (0.04 g) of bromine are added. Gas chromatography shows no nitrosamine. TEA analysis shows 0.03 ppm nitrosamine.
Eksempel 3Example 3
Nitrosaminfjernelse fra trifluralin, brom, højere temperatur, carbonatvask 30 g af en trifluralinprøve indeholdende 14 ppm nitrosamin opvarmes til 90°C. Der tilsættes 0,1 g brom, og reaktionsblandingen holdes ved 90°C i 30 minutter under omrøring. Reaktionsblandingen vaskes dernæst med 5 ml af en 10% opløsning af natriumcarbonat. Lagene adskilles, og en prøve af det organiske lag analyseres for nitrosaminindhold. Den viser 1,4 ppm nitrosamin. Det vandige lag ekstraheres med 5 ml methylenchlorid. En prøve af ekstrakten analyseres for nitrosaminindhold og viser 0,15 jig/ml.Nitrosamine removal from trifluralin, bromine, higher temperature, carbonate wash 30 g of a trifluralin sample containing 14 ppm nitrosamine is heated to 90 ° C. 0.1 g of bromine is added and the reaction mixture is maintained at 90 ° C for 30 minutes with stirring. The reaction mixture is then washed with 5 ml of a 10% solution of sodium carbonate. The layers are separated and a sample of the organic layer is analyzed for nitrosamine content. It shows 1.4 ppm nitrosamine. The aqueous layer is extracted with 5 ml of methylene chloride. A sample of the extract is analyzed for nitrosamine content and shows 0.15 µg / ml.
Eksempel 4 ..I. — iExample 4 ..I. - i
Nitrosaminfjernelse fra trifluralin, brom, oparbejdning med luft 27 g trifluralinprøve indeholdende 1750 ppm nitrosamin opvarmes til 70°C, og der tilsættes 0,2 g brom. Reaktionsblandingen holdes på 70°C i 55 minutter under omrøring. I de sidste 10 minutter blæses der luft over overfladen. Der udtages dernæst en prøve, og denne analyseres for nitrosaminindhold. Den viser 12 ppm nitrosamin.Nitrosamine removal from trifluralin, bromine, work-up with air 27 g of trifluralin sample containing 1750 ppm nitrosamine are heated to 70 ° C and 0.2 g of bromine is added. The reaction mixture is kept at 70 ° C for 55 minutes with stirring. For the last 10 minutes, air is blown over the surface. A sample is then taken and analyzed for nitrosamine content. It shows 12 ppm nitrosamine.
Eksempel 5 8Example 5 8
DK 152116BDK 152116B
Nitrosaminfjernelse fra trifluralin, brom, tidsstudieNitrosamine removal from trifluralin, bromine, time trial
En portion på 100 g af et trifluralinparti med et gennemsnitsindhold på 68 ppm nitrosamin opvarmes til 70°C, og der tilsættes 0,2 g brom. Reaktionsblandingen holdes ved 70°C i 2 timer under omrøring. Der udtages prøver periodisk, og disse analyseres for nitrosaminindhold. Resultaterne er som følger:A portion of 100 g of a trifluralin portion having an average content of 68 ppm nitrosamine is heated to 70 ° C and 0.2 g of bromine is added. The reaction mixture is kept at 70 ° C for 2 hours with stirring. Samples are taken periodically and analyzed for nitrosamine content. The results are as follows:
Tid indtil udtagning af prøven_Nitrosaminkoncentration 5 min. 3,2 ppm 15 min. 2,8 ppm 30 min. 2,2 ppm 1 time 14 .ppm 2 timer 27 ppmTime until sampling_Nitrosamine concentration 5 min. 3.2 ppm 15 min. 2.8 ppm 30 min. 2.2 ppm 1 hour 14 .ppm 2 hours 27 ppm
En anden prøve, der udtages efter 2 timer, analyseres for trifluralin ved dampfasechromatografi og bestemmes som 97,2% ren.Another sample taken after 2 hours is analyzed for trifluralin by vapor phase chromatography and determined as 97.2% pure.
Eksempel 6Example 6
Nitrosaminfjernelse fra trifluralin, større mængde bromNitrosamine removal from trifluralin, greater amount of bromine
En portion på 30 g af et trifluralinparti med et gennemsnitsindhold på 68 ppm nitrosamin opvarmes til 70°C, og der tilsættes 3,11 g brom. Reaktionsblandingen holdes ved 70°C i 30 minutter under omrøring. Reaktionsblandingen bliver mørk, og der iagttages noget mørkt, polymert materiale. Prøver analyseres for nitrosamin og trifluralinrenhed. Der påvises intet nitrosamin, renheden er 82,5%.A 30 g portion of a trifluralin portion having an average content of 68 ppm nitrosamine is heated to 70 ° C and 3.11 g of bromine is added. The reaction mixture is kept at 70 ° C for 30 minutes with stirring. The reaction mixture becomes dark and some dark polymeric material is observed. Samples are analyzed for nitrosamine and trifluralin purity. No nitrosamine is detected, the purity is 82.5%.
99
DK 152116 BDK 152116 B
Iflcsempel 7 fra ti if lur alin, tor dm, indvirkning af vandExample 7 from ten if lur alin, tor dm, effect of water
En portion på 30 g af et trifluralinparti med et gennemsnitsindhold på 68 ppm nitrosamin opvarmes til 70°C, og der tilsættes 6 -g vand. Der tilsættes 0,2 g brom. Reaktionsblandingen holdes '-på T0°C >i '30 minutter under omrøring. Lagene adskilles.A 30 g portion of a trifluralin portion having an average content of 68 ppm nitrosamine is heated to 70 ° C and 6 g of water is added. 0.2 g of bromine is added. The reaction mixture is kept at -0 ° C for 30 minutes with stirring. The layers are separated.
En prøve ^af -det'organiske lag, der analyseres for nitrosaminindhold, viser <1 ppm.A sample of the organic layers analyzed for nitrosamine content shows <1 ppm.
Eksempel 8 og 9Examples 8 and 9
Nitrosaminfjernelse fra trifluralin, brom, .Nitrosamine removal from trifluralin, bromine,.
sure betingelseracidic conditions
Der gennemføres to reaktioner under identiske betingelser med den undtagelse, at der ved den ene anvendes 0,5 ml koncentreret saltsyre og ved den anden 0,5 ml 50% svovlsyre.Two reactions are carried out under identical conditions except that 0.5 ml of concentrated hydrochloric acid is used and the other 0.5 ml of 50% sulfuric acid is used.
Ved hver reaktion blandes en portion på 30 g af et tri-fluralinparti med et gennemsnitsindhold på 68 ppm nitrosamin, 3 ml vand og den respektive syre, og blandingen opvarmes til 70°C. Der tilsættes 0,2 g brom, og blandingen holdes ved 70°C i 20 minutter under omrøring. Lagene adskilles dernæst. Syrelaget neutraliseres og ekstraheres med et lige så stort volumen methylenchlorid. Prøver af produktlaget og methylenchloridekstrakten analyseres for nitrosaminindhold. Resultaterne er som følger: N i tro s aminkoncentra ti on Methylenchlorid-For each reaction, a 30 g portion of a trifluralin portion is mixed with an average content of 68 ppm nitrosamine, 3 ml water and the respective acid, and the mixture is heated to 70 ° C. 0.2 g of bromine is added and the mixture is kept at 70 ° C for 20 minutes with stirring. The layers are then separated. The acid layer is neutralized and extracted with an equal volume of methylene chloride. Samples of the product layer and methylene chloride extract are analyzed for nitrosamine content. The results are as follows: N in faith s amine concentrations ten on methylene chloride
Syre_Produkt ekstrakt_Acid_Product Extract_
Eksempel 8 (Koncentreret saltsyre) 4,8 ppm 1,4 pg/mlExample 8 (Concentrated hydrochloric acid) 4.8 ppm 1.4 pg / ml
Eksempel 9Example 9
(50% svovlsyre) I-P I-P(50% sulfuric acid) I-P I-P
10 DK 152116 B10 DK 152116 B
Eksempel 10Example 10
Nitrosaminfjernelse fra trifluralin, chlorNitrosamine removal from trifluralin, chlorine
En portion på 30 g af et trifluralinparti med et gennemsnitsindhold på 68 ppm nitrosamin opvarmes til 70°C. Chlorgas bobles ind i trifluralinet med en hastighed på ca. 35 ml/min. i 30 minutter, og luft bobles dernæst ind i trifluralinet i yderligere 5 minutter. Trifluralinet holdes hele tiden på 70°C. En prøve analyseres og viser 16 ppm nitrosamin.A 30 g portion of a trifluralin portion having an average content of 68 ppm nitrosamine is heated to 70 ° C. Chlorine gas is bubbled into the triflural line at a rate of approx. 35 ml / min. for 30 minutes and then air is bubbled into the trifluralin for another 5 minutes. The trifluralin is kept at 70 ° C all the time. A sample is analyzed and shows 16 ppm nitrosamine.
Eksempel 11Example 11
Nitrosaminfjernelse fra trifluralin, chlor ved forhøjet temperatur og tilsætning af vand 1 ml vand og en portion på 30 g af et trifluralinparti med et gennemsnitsindhold på 68 ppm nitrosamin blandes og opvarmes til 90°C. Chlorgas bobles ind i blandingen med en hastighed på ca. 35 ml/min. i 30 minutter, hvorpå der bobles luft igennem i 10 minutter. Reaktionsblandingen holdes hele tiden på 90°C. En prøve analyseres og viser 13 ppm nitrosamin.Nitrosamine removal from trifluralin, chlorine at elevated temperature and addition of water 1 ml of water and a portion of 30 g of a trifluralin portion having an average content of 68 ppm nitrosamine are mixed and heated to 90 ° C. Chlorine gas is bubbled into the mixture at a rate of approx. 35 ml / min. for 30 minutes, then air is bubbled through for 10 minutes. The reaction mixture is kept at 90 ° C all the time. A sample is analyzed and shows 13 ppm nitrosamine.
Eksempel 12Example 12
Nitrosaminfjernelse fra trifluralin , tidsstudie af chlor ved forhøjet temperatur med carbonatvaskNitrosamine removal from trifluralin, time study of chlorine at elevated temperature with carbonate wash
En portion på 30 g af et trifluralinparti med et gennemsnitsindhold på 68 ppm nitrosamin opvarmes til og holdes på 110°C. Der tilsættes 2 ml 10% natriumcarbonatopløsning, og chlor bobles ind med en hastighed på 15 ml/min. Der udtages prøver periodisk.A 30 g portion of a trifluralin portion having an average content of 68 ppm nitrosamine is heated to and maintained at 110 ° C. 2 ml of 10% sodium carbonate solution is added and chlorine is bubbled at a rate of 15 ml / min. Samples are taken periodically.
I hver prøve adskilles lagene, og produktlaget analyseres for nitrosaminindhold. Resultaterne er som følger:In each sample, the layers are separated and the product layer analyzed for nitrosamine content. The results are as follows:
Tid indtil udtagning af prøven_Nitrosaminkoncentration 30 min. 15 ppm 1 time 28 ppm 2 timer 1,2 ppmTime until sampling_Nitrosamine concentration 30 min. 15 ppm 1 hour 28 ppm 2 hour 1.2 ppm
11 DK 152116 B11 DK 152116 B
Eksemoel 13Example 13
Nitrosaminfjemelse fra trifluralin, N-bromsuccinimidNitrosamine removal from trifluralin, N-bromosuccinimide
En portion på 30 g af et trifluralinparti med et gennemsnitsindhold på 68 ppm nitrosamin opvarmes til 70°C, og der tilsættes 0,5 g N-bromsuccinimid. Reaktionsblandingen holdes på 70°C i 30 minutter. En prøve analyseres og viser 1,7 ppm nitrosamin.A 30 g portion of a trifluralin portion having an average content of 68 ppm nitrosamine is heated to 70 ° C and 0.5 g of N-bromosuccinimide is added. The reaction mixture is kept at 70 ° C for 30 minutes. A sample is analyzed and shows 1.7 ppm nitrosamine.
Eksempel 14Example 14
Nitrosaminfjernelse fra trifluralin, brom med carbonat-forbehandling af trifluralinNitrosamine removal from trifluralin, bromine with carbonate pretreatment of trifluralin
En portion på 30 g af et trifluralinparti med et gennemsnitsindhold på 68 ppm nitrosamin smeltes og vaskes med 15 ml 5% natriumcarbonatopløsning. Lagene adskilles. Der sættes 0,1 g brom til trifluralinlaget ved 70°C, og blandingen holdes på 70°C i 30 minutter. En prøve analyseres for nitrosaminindhold. Der påvises ikke noget.A 30 g portion of a trifluralin portion having an average content of 68 ppm nitrosamine is melted and washed with 15 ml of 5% sodium carbonate solution. The layers are separated. 0.1 g of bromine is added to the trifluralin layer at 70 ° C and the mixture is kept at 70 ° C for 30 minutes. A sample is analyzed for nitrosamine content. Nothing is detected.
Eksempel 15Example 15
Nitrosaminfjernelse fra dinitramin., bromNitrosamine removal from dinitramine., Bromine
Til 10 g dinitraminprøve indeholdende 138 ppm nitrosamin sættes 0,2 g brom under overfladen ved 110°C. Reaktionsblandingen bliver mørk. Den omrøres i 30 minutter, og en prøve på 2 g (betegnet A) udtages. De resterende 8 g sættes langsomt til 60 ml methylenchlorid, og der tilsættes 15 ml 10% natriumcarbonatopløs-ning. Det organiske lag fraskilles, og opløsningsmidlet fjernes på en rotationsfordamper i 15 minutter ved 45°C (prøve B).To 10 g of dinitramine sample containing 138 ppm nitrosamine, 0.2 g of bromine is added below the surface at 110 ° C. The reaction mixture becomes dark. It is stirred for 30 minutes and a sample of 2 g (denoted A) is taken. The remaining 8 g is slowly added to 60 ml of methylene chloride and 15 ml of 10% sodium carbonate solution is added. The organic layer is separated and the solvent removed on a rotary evaporator for 15 minutes at 45 ° C (sample B).
Hver prøve analyseres for nitrosaminindhold med TEA. Resultaterne er som følger:Each sample is analyzed for nitrosamine content with TEA. The results are as follows:
Prøve_Nitrosaminkoncentration A <0,2 B 0,3Sample_Nitrosamine concentration A <0.2 B 0.3
Claims (9)
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US82534577A | 1977-08-17 | 1977-08-17 | |
| US82534577 | 1977-08-17 | ||
| US87883578 | 1978-02-17 | ||
| US05/878,835 US4127610A (en) | 1977-08-17 | 1978-02-17 | Dinitroaniline purification with bromine and chlorine |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| DK362578A DK362578A (en) | 1979-02-18 |
| DK152116B true DK152116B (en) | 1988-02-01 |
| DK152116C DK152116C (en) | 1988-06-20 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DK362578A DK152116C (en) | 1977-08-17 | 1978-08-16 | PROCEDURE FOR REDUCING NITROSAMINE CONTENT IN DINITROANILINES |
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| Country | Link |
|---|---|
| JP (1) | JPS5822101B2 (en) |
| AR (1) | AR221489A1 (en) |
| AU (1) | AU518675B2 (en) |
| BG (1) | BG34332A3 (en) |
| BR (1) | BR7805279A (en) |
| CA (1) | CA1057774A (en) |
| CS (1) | CS222270B2 (en) |
| DD (1) | DD138312A5 (en) |
| DE (1) | DE2835530C2 (en) |
| DK (1) | DK152116C (en) |
| ES (1) | ES472550A1 (en) |
| FR (1) | FR2400503A1 (en) |
| GB (1) | GB2003148B (en) |
| HU (1) | HU179460B (en) |
| IE (1) | IE47178B1 (en) |
| IL (1) | IL55354A (en) |
| IT (1) | IT1098023B (en) |
| MX (1) | MX5204E (en) |
| NL (1) | NL180100C (en) |
| PL (1) | PL120364B1 (en) |
| RO (1) | RO75536A (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2920448C3 (en) * | 1979-05-21 | 1982-02-11 | Hoechst Ag, 6000 Frankfurt | Process for removing nitrosating agent (s) from nitrated aromatic compounds |
| EP0019281B1 (en) * | 1979-05-21 | 1982-12-29 | Hoechst Aktiengesellschaft | Process for the removal of nitrozation agents from nitrated aromatic compounds |
| DE2926947C2 (en) * | 1979-07-04 | 1982-03-18 | Hoechst Ag, 6000 Frankfurt | Process for removing nitrosating agent (s) from nitrated aromatic compounds |
| IT1131182B (en) * | 1980-05-15 | 1986-06-18 | Montedison Spa | PREPARATION PROCESS OF N-DI-N-PROPIL-2,6-DINITRO-4-TRIFLUOROMETILANILINA WITH LOW NITROSAMINE CONTENT |
| IT1195822B (en) * | 1986-08-12 | 1988-10-27 | I Pi Ci Spa | TRIFLURALINE PURIFICATION PROCEDURE |
| US5922915A (en) * | 1998-05-11 | 1999-07-13 | Srm Chemical, Ltd., Co. | Process for removing N-nitroso compounds from organo-amine compositions including dinitroaniline herbicides |
| CN107106970B (en) * | 2015-01-07 | 2020-06-09 | 三菱日立电力系统株式会社 | Method and apparatus for treating nitroso compound |
-
1978
- 1978-08-10 GB GB7832840A patent/GB2003148B/en not_active Expired
- 1978-08-14 MX MX787310U patent/MX5204E/en unknown
- 1978-08-14 ES ES472550A patent/ES472550A1/en not_active Expired
- 1978-08-14 IT IT26768/78A patent/IT1098023B/en active
- 1978-08-14 RO RO7894976A patent/RO75536A/en unknown
- 1978-08-14 IL IL55354A patent/IL55354A/en unknown
- 1978-08-14 PL PL1978209046A patent/PL120364B1/en unknown
- 1978-08-14 AR AR273298A patent/AR221489A1/en active
- 1978-08-14 HU HU78EI804A patent/HU179460B/en not_active IP Right Cessation
- 1978-08-14 DE DE2835530A patent/DE2835530C2/en not_active Expired
- 1978-08-15 CA CA309,416A patent/CA1057774A/en not_active Expired
- 1978-08-15 CS CS785322A patent/CS222270B2/en unknown
- 1978-08-16 BG BG7840680A patent/BG34332A3/en unknown
- 1978-08-16 BR BR7805279A patent/BR7805279A/en unknown
- 1978-08-16 FR FR7823852A patent/FR2400503A1/en active Granted
- 1978-08-16 IE IE1649/78A patent/IE47178B1/en not_active IP Right Cessation
- 1978-08-16 DD DD78207319A patent/DD138312A5/en unknown
- 1978-08-16 DK DK362578A patent/DK152116C/en not_active IP Right Cessation
- 1978-08-16 NL NLAANVRAGE7808479,A patent/NL180100C/en not_active IP Right Cessation
- 1978-08-17 AU AU39028/78A patent/AU518675B2/en not_active Expired
- 1978-08-17 JP JP53100850A patent/JPS5822101B2/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| NL7808479A (en) | 1979-02-20 |
| IL55354A (en) | 1981-05-20 |
| DD138312A5 (en) | 1979-10-24 |
| AU518675B2 (en) | 1981-10-15 |
| DE2835530C2 (en) | 1982-10-21 |
| GB2003148A (en) | 1979-03-07 |
| GB2003148B (en) | 1982-02-10 |
| PL120364B1 (en) | 1982-02-27 |
| IT7826768A0 (en) | 1978-08-14 |
| JPS5822101B2 (en) | 1983-05-06 |
| AR221489A1 (en) | 1981-02-13 |
| PL209046A1 (en) | 1979-05-07 |
| BG34332A3 (en) | 1983-08-15 |
| FR2400503A1 (en) | 1979-03-16 |
| DE2835530A1 (en) | 1979-03-01 |
| JPS5441826A (en) | 1979-04-03 |
| IE781649L (en) | 1979-02-17 |
| CS222270B2 (en) | 1983-06-24 |
| CA1057774A (en) | 1979-07-03 |
| FR2400503B1 (en) | 1980-10-31 |
| ES472550A1 (en) | 1979-10-16 |
| IL55354A0 (en) | 1978-10-31 |
| DK362578A (en) | 1979-02-18 |
| AU3902878A (en) | 1980-02-21 |
| RO75536A (en) | 1980-11-30 |
| DK152116C (en) | 1988-06-20 |
| IE47178B1 (en) | 1984-01-11 |
| NL180100C (en) | 1987-01-02 |
| HU179460B (en) | 1982-10-28 |
| NL180100B (en) | 1986-08-01 |
| IT1098023B (en) | 1985-08-31 |
| MX5204E (en) | 1983-04-25 |
| BR7805279A (en) | 1979-04-10 |
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