EP0000495B1 - Procédé pour la préparation d'acide amino-1-hydroxy-8-naphtalènedisulfonique-3,6 (acide-H). - Google Patents

Procédé pour la préparation d'acide amino-1-hydroxy-8-naphtalènedisulfonique-3,6 (acide-H). Download PDF

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Publication number
EP0000495B1
EP0000495B1 EP78100358A EP78100358A EP0000495B1 EP 0000495 B1 EP0000495 B1 EP 0000495B1 EP 78100358 A EP78100358 A EP 78100358A EP 78100358 A EP78100358 A EP 78100358A EP 0000495 B1 EP0000495 B1 EP 0000495B1
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EP
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Prior art keywords
acid
reaction
process according
naphthylamine
carried out
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EP78100358A
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German (de)
English (en)
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EP0000495A1 (fr
Inventor
Willi Dr. Schössler
Rolf Dr. Pütter
Horst Dr. Behre
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Bayer AG
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Bayer AG
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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C303/00—Preparation of esters or amides of sulfuric acids; Preparation of sulfonic acids or of their esters, halides, anhydrides or amides
    • C07C303/02—Preparation of esters or amides of sulfuric acids; Preparation of sulfonic acids or of their esters, halides, anhydrides or amides of sulfonic acids or halides thereof
    • C07C303/22—Preparation of esters or amides of sulfuric acids; Preparation of sulfonic acids or of their esters, halides, anhydrides or amides of sulfonic acids or halides thereof from sulfonic acids, by reactions not involving the formation of sulfo or halosulfonyl groups; from sulfonic halides by reactions not involving the formation of halosulfonyl groups

Definitions

  • the present invention relates to a process for the preparation of 1-amino-8-naphthol-3,6-disulfonic acid (H-acid) as the monoalkali salt from 1-naphthylamino-3,6,8-trisulfonic acid by alkaline pressure hydrolysis.
  • H-acid 1-amino-8-naphthol-3,6-disulfonic acid
  • 1-Amino-8-naphthol-3,6-disulfonic acid which is often also referred to as H-acid, is an important intermediate for the production of dyes (see Ullmanns Enzyklopadie der Technischen Chemie, 3rd edition, 12th volume, p . 621).
  • the acidic calcium sodium salt of T-acid (1-naphthylamine-3,6,8-trisulfonic acid) is precipitated, which is filtered off and washed several times.
  • This salt is added to the washing water and soda is added.
  • the chalk that has precipitated is pressed and the salt solution is concentrated.
  • the concentrated trisodium salt solution of the T-acid is reacted with 50% sodium hydroxide solution under pressure.
  • sulfuric acid is added first, then water, and finally the H acid is obtained as the monosodium salt by filtration, washing and drying.
  • T-acid e.g. 1-amino-6-naphthol-3,8-disulfonic acid, an isomer of H-acid known under the name W-acid, and 1,8-dihydroxy-naphthalene-3,6-disulfonic acid, one under the name Chromotrop Acid known secondary product of H acid.
  • W-acid e.g. 1-amino-6-naphthol-3,8-disulfonic acid
  • W-acid 1,8-dihydroxy-naphthalene-3,6-disulfonic acid
  • Chromotrop Acid known secondary product of H acid.
  • the yield of H acid in the process described above is generally only 70 to 72%, based on the T acid used.
  • a method has now been found for the preparation of 1-amino-8-naphthol-3,6-disulfonic acid monoalkali salts by reacting 1-naphthylamine-3,6,8-trisulfonic acid and / or its salts and / or naphthylamine-trisulfonic acid.
  • 1-naphthylamine-3,6,8-trisulfonic acid can be used in pure form and / or in the form of naphthylamine-trisulfonic acid isomer mixtures.
  • the naphthylamine-trisulfonic acid isomer mixtures generally contain more than 65% by weight of 1-naphthylamine-3,6, B-trisulfonic acid, based on the total amount of diazotizable substance. If naphthylamine-trisulfonic acid isomer mixtures are used, preference is given to using those containing 70 to 90% by weight of 1-naphthylamine-3,6-B-trisulfonic acid.
  • a naphthylamine-trisulfonic acid isomer mixture to be used with particular preference contains
  • Naphthylamine-trisulfonic acid isomer mixtures can contain other products in addition to the naphthylamine trisulfonic acids.
  • Such products can in particular be by-products, decomposition products or unreacted intermediates from the production stages for naphthylamine-trisulfonic acid, for example naphthalene-di-, -tri- and -tetra-sulfonic acids, nitronaphthalene-mono-, -di and -trisulfonic acids, naphthylamine-mono- and disulfonic acids, e.g.
  • 1-naphthylamine-3,6- and -5,7-disulfonic acid also dinaphthylsulfonic sulfonic acids and their amino and nitrodivatives, and oxidation products of naphthalene and / or naphthalenesulfonic acids, which can be formed during sulfonation and / or nitration.
  • the 1-naphthylamine-3,6,8-trisulfonic acid or the naphthylamine trisulfonic acid isomer mixtures can be used in free form, in the form of neutral salts or in the form of acid salts will. Mixtures containing free acids and salts can also be used. If all or part of the 1-naphthylamine-3,6,8-trisulfonic acid or the naphthylamine-trisulfonic acid isomer mixtures are present as salts, the alkali and alkaline earth metal salts, in particular the sodium and potassium salts, are preferred.
  • Suitable 1-naphthylamine-3,6,8-trisulfonic acid or salts of this acid for use in the process according to the invention can be obtained by trisulfonating naphthalene, nitriding the resulting mixture, then reducing the nitro-naphthalene-trisulfonic acid mixture present, the acidic Calcium-sodium salt of the T-acid precipitates, this salt is mixed with soda in solution, the precipitated chalk is pressed out and the salt solution is concentrated. These reactions can be carried out according to the FIAT Final Report procedure described at the beginning or in any other way.
  • a naphthylamine-trisulfonic acid isomer mixture suitable for use in the process according to the invention can be obtained in a similar manner if the reaction sequence is terminated after the reduction of the nitro-naphthalenetrisulfonic acid mixture has ended.
  • the 1-naphthylamine-3,6,8-trisulfonic acid and / or its salts and / or the naphthylamine-trisulfonic acid isomer mixture and / or its salts can be, for example, in solid form or as an aqueous solution with a content of, for example, 20 to 50% by weight. -%, preferably 30 to 40% by weight, calculated as the free acid with the molecular weight 383, can be used.
  • Alkali hydroxide solutions for the process according to the invention are in particular aqueous potassium or sodium hydroxide solution.
  • the use of potassium hydroxide leads to better yields compared to sodium hydroxide solution, but sodium hydroxide solution is generally cheaper.
  • the use of 6 to 9 moles of alkali metal hydroxide per mole of diazotizable substance is particularly preferred.
  • the concentration of alkali hydroxide in the reaction mixture can be, for example, 10 to 50% by weight (based on the sum of alkali hydroxide plus water plus alcohol). This concentration is preferably 25 to 35%.
  • An essential aspect of the process according to the invention is that it is carried out in the presence of alcohols and / or alcoholates and in the presence of nitric acid, nitrous acid, nitrogen oxides, nitrates, nitrites, nitro compounds or nitroso compounds.
  • the alcohols to be added can be added to the reaction mixture, for example in pure form, in a mixture with water or in the form of alcoholates, for example in the form of alkali alcoholates.
  • Suitable alcohols are those alcoholic compounds which are miscible with water under the reaction conditions and which undergo no or only minor undesirable side reactions with strong alkali. In this case, the formation of alcoholate is not an undesirable side reaction.
  • Aliphatic alcohols with, for example, 1-6 carbon atoms are preferred.
  • primary, secondary and tertiary monohydric and polyhydric alcohols can be used, the hydroxyl groups of which can also be wholly or partially etherified.
  • Possible monohydric alcohols include: methanol, ethanol, n-propanol, 2-propanol, n-butanol, iso-butanol, tert-butanol.
  • polyhydric alcohols are e.g. in question: ethylene glycol, propanediols, butanediols, glycerol, butanetriols; Monoglyme, Digiyme, Of course, mixtures of alcohols can also be used. Methanol is particularly preferably used.
  • the amount of alcohol or alcoholate to be used can be granted, for example, in such a way that 10 to 80% by weight, preferably 25 to 60% by weight, of alcohol or alcoholate, based on the sum of water plus alcohol, is present.
  • suitable nitrogen oxides are N z 0 5 , N 2 0 4 , N z 0 3 , N0 2 and NO, preferably N 2 0 5 and N 2 0 4 or N0 2 .
  • Suitable nitrates are, for example, alkali metal nitrates, ammonium nitrates, alkaline earth metal nitrates and other metal nitrates, including heavy metal nitrates.
  • Alkali metal nitrates, in particular sodium or potassium nitrate, are preferably used.
  • suitable nitrites are alkali metal nitrites, in particular sodium nitrite.
  • Suitable nitro compounds are aromatic and aliphatic nitro compounds, such as nitrobenzenes, nitronaphthalenes, nitrobenzenesulfonic acid, nitronaphthalene mono-, di- and trisulfonic acids, nitromethane, nitroethane and nitropropane.
  • suitable nitroso compounds are nitrosobenzenes.
  • the process according to the invention is particularly preferably carried out in the presence of sodium nitrate or potassium nitrate.
  • the additives described above can be introduced into the process according to the invention in pure form or as a solution, for example as a solution in water, aqueous alkali or alcohol. Of course, 2 or more of the additives mentioned can also be used.
  • NO-containing substances are present in small amounts in the reaction mixture. You can, for example, use as much of these substances Introduce into the reaction mixture that, based on 1 mol of 1-naphthylamine-3,6,8-trisulfonic acid or 1 mol of naphthylamine-trisulfonic acid isomer mixture or 1 mol of salts of these acids, there are 0.005 to 1 mol of these substances. These substances are preferably present in an amount of 0.01 to 0.5 mol, in particular in an amount of 0.01 to 0.1 mol (reference as above).
  • the process according to the invention can be carried out, for example, at temperatures from 150 to 250 ° C., preferably at 180 to 220 ° C., in a closed vessel.
  • the pressure which arises is generally completely sufficient to carry out the process according to the invention in a satisfactory manner.
  • the method according to the invention can also be carried out with pressures other than those which set themselves in closed vessels. For example, pressures in the range from 5 to 100 bar are possible for the process according to the invention.
  • the reaction time essentially depends on the reaction temperature and the alkali hydroxide concentration. It is shorter at relatively high reaction temperatures and at relatively high alkali hydroxide concentrations and longer at relatively low reaction temperatures and relatively low alkali hydroxide concentrations and is generally from 10 minutes to 10 hours. For example, good results are obtained at a reaction temperature of approx. 200 ° C. and an alkali hydroxide concentration of 30% by weight with a reaction time of 45-60 minutes.
  • the substances to be used in the process according to the invention are most conveniently introduced into the reaction vessel at a temperature such that the desired reaction temperature is present after the heat of mixture and optionally the heat of neutralization has been released.
  • the substances to be entered can also be brought together at lower temperatures and heated to the desired reaction temperature in the reaction vessel.
  • the reaction mixture After the reaction has ended and before the H acid has been separated off as the monoalkali metal salt, it is advantageous to cool the reaction mixture and / or to dilute it with water. You can, for example, on. Cool temperatures in the range of 20 to 150 ° C, preferably to temperatures in the range of 80 to 120 ° C '.
  • the amount of water to be added depends on the reaction conditions, e.g. the type of alkali metal hydroxide, its amount and concentration, and the amount of alcohol that may still be present. It is advantageous to choose the amount of water so that the alkali sulfite formed in the reaction is dissolved or remains dissolved.
  • the H-acid can be separated off as the monoalkali salt by acidifying the reaction mixture with mineral acids.
  • Sulfuric acid is preferably used for this.
  • Sufficient mineral acid is added to form the sparingly soluble monoalkali salt of H-acid.
  • concentration of the mineral acid and / or by adding water before and / or during the addition of the mineral acid it is expediently ensured that the inorganic salt which forms, e.g. Sodium sulfate or potassium sulfate, does not fail.
  • a pH in the range 0 to 4 preferably 0.5 to 2.5
  • the monoalkali salt of the H-acid can be separated off in a customary manner, for example by filtration. Before the monoalkali salt of H-acid is separated off, it is advantageous to set the temperature to less than 80 ° C. by cooling, for example by evaporative cooling, and to carry out the separation at a temperature of less than 80 ° C.
  • the separation is preferably carried out at a temperature in the range from 20 to 60 ° C.
  • the monoalkali salt of H-acid present after the separation is usually washed with water and dried, for example in vacuo.
  • the alcohol can be separated off at various points during the working up of the reaction mixture. It is possible to separate the alcohol from an alkaline, neutral or acidic solution before or after the H-acid has been separated off as the monoalkali salt.
  • the alcohol is preferably separated from alkaline or neutral solution and by distillation. It is particularly preferred to distill off the alcohol directly from the reaction mixture, optionally after cooling and / or dilution with water, via a column. If low-boiling alcohols, for example methanol, are used, it may be sufficient to start the distillation without external heat input by depressurization. If the alcohol used segregates from the reaction mixture at temperatures lower than the reaction temperature, it is also possible to separate the alcohol by phase separation after the reaction mixture has cooled.
  • the separated alcohol is preferably reused in the process according to the invention. It is then only necessary, possibly during the alkaline pressure hydrolysis and / or during the Processing to supplement lost alcohol content.
  • the process according to the invention provides the advantage over the known processes for the preparation of 1-amino-8-naphthol-3,6-disulfonic acid (H-acid) as the monoalkali salt that higher yields can be achieved and the formation of by-products, in particular the formation of 1-Amino-6-naphthol-3,8-disulfonic acid (W-acid) and the formation of 1,8-dihydroxynaphthalene-3,6- . disulfonic acid (chromotropic acid) is significantly reduced.
  • the reduced content of the W-acid which is sparingly soluble in acidic solution, also means that the monoalkali salt of the H-acid can be isolated in a particularly pure form without intensive washing which is associated with losses in yield.
  • the reaction mixtures freed from methanol are acidified at pH 1 to 1.5 in a pH-controlled manner, with about 1000 g of 50% strength by weight sulfuric acid, refluxed for one hour to remove sulfur dioxide, cooled to 40 ° C. under evaporative cooling and kept at 40 ° C for two hours.
  • the product is filtered at 40 ° C, washed with a total of 500 g of water and dried at 80 ° C in a vacuum.
  • the yields and the H-acid quality which was determined by high pressure liquid chromatography, are listed in Table 2.
  • T-acid trisodium salt content 15.3 g of nitrite / 100 g, 85.1% by weight of T-acid MG 383; a total of 69 g of nitrite
  • a total of 69 g of nitrite are placed in a 2.7 I nickel autoclave.
  • 474 g of 70% by weight sodium hydroxide solution (8.3 mol NaOH) are heated to 215 ° C.
  • the contents of the specified acids are calculated on free acids.
  • the salts mentioned in Example 1 are in fact present.
  • the product is washed with a total of 5.4 kg of water and dried in vacuo at 80 ° C.
  • the yield is 82% based on T acid.
  • the qualities of the product determined by high pressure liquid chromatography are listed in Table 5.
  • Reaction products from the isomeric naphthylamine trisulfonic acids are not contained in the isolated product.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Claims (11)

1. Procédé de production de sels mono-alcalins d'acide 1-amino-8-naphtot-3,6-disutfonique par réaction d'acide 1-naphtylamine-3,6,8-trisulfonique et/ou de ses sels et/ou de mélanges d'isomères d'acide naphtylamine-trisulfonique et/ou de leurs sels avec une solution d'hydroxide alcalin sous pression élevée et à température élevée et précipitation des sels mono-alcalins d'acide 1-amino-8-naphtol-3,6-disulfonique par acidification, caractérisé en ce qu'on conduit la réaction en présence d'alcools et/ou d'alcoolates et en présence d'acide nitrique, d'acide nitreux, d'oxydes d'azote, de nitrates, de nitrites, de composés nitrés ou de composés nitroso.
2. Procédé suivant la revendication 1, caractérisé en ce qu'on conduit la réaction en présence d'alcools aliphatiques ayant 1 à 6 atomes de carbone.
3. Procédé suivant les revendications 1 et 2, caractérisé en ce qu'on conduit la réaction en présence de méthanol.
4. Procédé suivant les revendications 1 à 3, caractérisé en ce que 10 à 80% en poids d'alcool et/ou d'alcoolate par rapport à la somme eau plus alcool sont présents pendant la réaction.
5. Procédé suivant les revendications 1 à 4, caractérisé en ce qu'il est mis en oeuvre en présence de nitrate de sodium ou de nitrate de potassium.
6. Procédé suivant les revendications 1 à 5, caractérisé en ce qu'on introduit dans le mélange réactionnel 0,005 à 1 mole d'acide nitrique, d'acide nitreux, d'oxydes d'azote, de nitrates, de nitrites, de composés nitrés ou de composés nitroso par mole d'acide 1-naphtylamÍne-3,6,S-trisulfonique utilisé ou par mole de mélange d'isomères d'acide naphtylamine-trisulfonique utilisé ou par mole de sels de ces acides.
7. Procédé suivant les revendications 1 à 6, caractérisé en ce qu'on conduit la réaction à des températures de 150 à 250°C.
8. Procédé suivant les revendications 1 à 7, caractérisé en ce qu'on conduit la réaction sous pression autogène dans un récipient clos.
9. Procédé suivant les revendications 1 à 7, caractérisé en ce qu'on conduit la réaction à une pression de 5 à 100 bars.
10. Procédé suivant les revendications 1 à 9, caractérisé en ce qu'on sépare l'alcool de la solution alcaline ou neutre par distillation après la réaction.
11. Procédé suivant la revendication 10, caractérisé en ce qu'on réutilise l'alcool séparé.
EP78100358A 1977-07-16 1978-07-11 Procédé pour la préparation d'acide amino-1-hydroxy-8-naphtalènedisulfonique-3,6 (acide-H). Expired EP0000495B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE2732266 1977-07-16
DE19772732266 DE2732266A1 (de) 1977-07-16 1977-07-16 Verfahren zur herstellung von 1-amino-8-naphthol-3,6-disulfonsaeure (h-saeure)

Publications (2)

Publication Number Publication Date
EP0000495A1 EP0000495A1 (fr) 1979-02-07
EP0000495B1 true EP0000495B1 (fr) 1980-11-26

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EP78100358A Expired EP0000495B1 (fr) 1977-07-16 1978-07-11 Procédé pour la préparation d'acide amino-1-hydroxy-8-naphtalènedisulfonique-3,6 (acide-H).

Country Status (6)

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US (1) US4166826A (fr)
EP (1) EP0000495B1 (fr)
JP (1) JPS5419955A (fr)
BR (1) BR7804542A (fr)
DE (2) DE2732266A1 (fr)
IT (1) IT7850308A0 (fr)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4325889A (en) * 1978-08-04 1982-04-20 Bayer Aktiengesellschaft Process for the preparation of 1-amino-8-naphthol-3,6-disulphonic acid (H-acid)
DE2843680A1 (de) * 1978-10-06 1980-04-24 Bayer Ag Verfahren zur herstellung von 1-amino-8-naphthol-4,6-disulfonsaeure (k-saeure)
DE3118147A1 (de) 1981-05-07 1982-12-02 Bayer Ag, 5090 Leverkusen Verfahren zur isolierung von h-saeure und k-saeure
CN1057521C (zh) * 1997-08-16 2000-10-18 吉林化学工业股份有限公司染料厂 1－氨基－8－奈酚－3.6二磺酸单钠盐生产工艺的改进
CN108003071A (zh) * 2017-12-04 2018-05-08 大柴旦乐青科技化学有限公司 一种h酸高压碱熔工艺
CN107986997A (zh) * 2017-12-08 2018-05-04 荆门市熊兴化工有限公司 一种用于h酸生产过程中的碱熔方法
CN109096154A (zh) * 2018-08-16 2018-12-28 山东裕源集团有限公司 一种h酸生产工艺

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1573056A (en) * 1925-05-09 1926-02-16 Newport Co Process of preparing 1, 8-aminonaphthol sulphonic acids
US1670406A (en) * 1925-05-09 1928-05-22 Newport Co Process of preparing h-acid

Also Published As

Publication number Publication date
DE2732266A1 (de) 1979-02-01
US4166826A (en) 1979-09-04
EP0000495A1 (fr) 1979-02-07
JPS5419955A (en) 1979-02-15
DE2860341D1 (en) 1981-02-12
BR7804542A (pt) 1979-03-20
IT7850308A0 (it) 1978-07-14

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