WO1995014660A1 - Process for producing aqueous solutions of ether sulphate salts with a reduced 1,4 dioxane content - Google Patents

Process for producing aqueous solutions of ether sulphate salts with a reduced 1,4 dioxane content Download PDF

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Publication number
WO1995014660A1
WO1995014660A1 PCT/EP1994/003793 EP9403793W WO9514660A1 WO 1995014660 A1 WO1995014660 A1 WO 1995014660A1 EP 9403793 W EP9403793 W EP 9403793W WO 9514660 A1 WO9514660 A1 WO 9514660A1
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WIPO (PCT)
Prior art keywords
dioxane
aqueous solutions
solution
aqueous
ether
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PCT/EP1994/003793
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German (de)
French (fr)
Inventor
Christoph Breucker
Günter Hendricks
Helmut Jenne
Günter PANTHEL
Wolfgang Schmidt
Roland Spörer
Norbert Wrede
Original Assignee
Henkel Kommanditgesellschaft Auf Aktien
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Publication of WO1995014660A1 publication Critical patent/WO1995014660A1/en

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    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K8/00—Cosmetics or similar toiletry preparations
    • A61K8/18—Cosmetics or similar toiletry preparations characterised by the composition
    • A61K8/30—Cosmetics or similar toiletry preparations characterised by the composition containing organic compounds
    • A61K8/46—Cosmetics or similar toiletry preparations characterised by the composition containing organic compounds containing sulfur
    • A61K8/463—Cosmetics or similar toiletry preparations characterised by the composition containing organic compounds containing sulfur containing sulfuric acid derivatives, e.g. sodium lauryl sulfate
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61Q—SPECIFIC USE OF COSMETICS OR SIMILAR TOILETRY PREPARATIONS
    • A61Q5/00—Preparations for care of the hair
    • A61Q5/02—Preparations for cleaning the hair
    • 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
    • C07C303/24—Preparation of esters or amides of sulfuric acids; Preparation of sulfonic acids or of their esters, halides, anhydrides or amides of esters of sulfuric acids
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K23/00—Use of substances as emulsifying, wetting, dispersing, or foam-producing agents
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K23/00—Use of substances as emulsifying, wetting, dispersing, or foam-producing agents
    • C09K23/04—Sulfonates or sulfuric acid ester salts derived from polyhydric alcohols or amino alcohols or derivatives thereof

Definitions

  • the invention relates to a process for the preparation of aqueous solutions of ether sulfate salts with a reduced content of 1,4-dioxane, in which the aqueous solutions are first treated with superheated steam and then placed on the turntable of an evacuated defoaming vessel.
  • Fatty alcohol polyglycol ether sulfates and alkylphenol polyglycol ether sulfates which are subsumed under the collective name "ether sulfates", are anionic surfactants which, because of their intensive foaming power, low sensitivity to hardness, good cleaning performance and advantageous skin cosmetic tolerance, are often used to produce manual dishwashing detergents, other hair-treatment agents and other surface-active agents Products that come into contact with human skin are used.
  • the preparation of the ether sulfates is based on the corresponding hydroxy compounds - preferably fatty alcohols or alkylphenols - which are first reacted with alkylene oxides to give the polyglycol ethers, then sulfated with sulfur trioxide or chlorosulfonic acid and finally neutralized with aqueous bases.
  • a problem in the production of ether sulfates is the proportion of impurities, in particular 1,4-dioxane, which results from an autocatalytic degradation of the polyglycol ether chain at the stage of the non-neutralized sulfation products.
  • NRE narrow range ethoxylates
  • US Pat. No. 4,285,881 describes a process in which 1,4-dioxane is separated from ether sulfate solutions with water vapor at temperatures from 25 to 150 ° C. in a thin film evaporator.
  • ether sulfate solutions with a solids content of 60 to 80% by weight are deodorized by heat treatment at 50 to 130 ° C. under reduced pressure, 1,4-dioxane also being removed .
  • DE-A1 30 44 488 (Henkel) reports on a process for reducing the dioxane content in ether sulfates, in which ether sulfate solutions with a solids content of 50 to 80% by weight are first prepared and an azeotrope is produced therefrom Water and 1,4-dioxane evaporated.
  • DE-Al 34 47 867 also relates to a process for separating 1,4-dioxane from ether sulfates, in which the aqueous solutions are treated with steam at 110 ° C. in the presence of a silicone defoamer; a similar process is also known from EP-Bl 0 283 862 (Henkel). Without exception, the methods mentioned are associated with a high technical outlay, are not very economical and their results are not always satisfactory.
  • DE-C2 37 40 695 describes a process for removing 1,4-dioxane in which the ether sulfate solutions are treated with zeolites.
  • ether sulfates with a low content of 1,4-dioxane can be obtained by sulfating the polyglycol ethers in the presence of ethoxylated fatty acid amides or Performs thiourea and other amine compounds.
  • EP-Bl 0327 007 Hoechst water
  • the acidic sulfation products before neutralization or add short chain alcohols In this way, however, mixtures of ether sulfates with other substances are obtained which are undesirable from an application point of view.
  • the object of the invention was therefore to develop a new, continuous process for the production of aqueous, highly concentrated solutions of ether sulfate salts with a reduced content of 1,4-dioxane, which is free from the disadvantages described.
  • the invention relates to a process for the preparation of aqueous solutions of ether sulfate salts with a reduced content of 1,4-dioxane, in which process continuously
  • an aqueous ether sulfate solution is heated to a temperature of 80 to 120 ° C by direct admixing of superheated steam in a continuous intensive mixer of the rotor-stator type, b) the heated solution is placed on the turntable of an evacuated defoaming vessel and c) the concentrated solution, which is largely freed of 1,4-dioxane, is separated off.
  • ether sulfates is used to sum up anionic surfactants which have an anionic sulfate group in direct connection with a nonionic polyglycol ether chain and follow the formula (I),
  • R 1 is a linear or branched aliphatic hydrocarbon radical having 6 to 22 carbon atoms and 0 and / or 1 to 3 double bonds or an alkylphenyl radical having 6 to 10 carbon atoms in the alkyl radical, m for numbers from 1 to 20, n for numbers from 0 to 20 and X represents an alkali and / or alkaline earth metal, ammonium, alkylammonium, alkanolammonium or glucammonium.
  • fatty alcohol ether sulfates of the formula (I) in which R 1 is an alkyl and / or alkenyl radical having 6 to 22, preferably 12 to 18 carbon atoms, m is a number from 1 to 10, n is 0 and X is sodium or Magnesium stands.
  • R 1 is an alkyl and / or alkenyl radical having 6 to 22, preferably 12 to 18 carbon atoms
  • m is a number from 1 to 10
  • n is 0
  • X sodium or Magnesium stands.
  • examples are the sulfates of the adducts of on average 1 to 10, preferably 2 to 5, moles of ethylene oxide
  • the fatty alcohol ether sulfates can have both a conventional and a narrow homolog distribution with regard to their polyglycol ether chain.
  • ether sulfates are the alkylaryl ether sulfates, in particular the alkylphenol ether sulfates, such as the sulfates of the adducts of ethylene oxide with alkylphenols.
  • alkylphenol ether sulfates such as the sulfates of the adducts of ethylene oxide with alkylphenols.
  • Typical examples are the sulfates of the adducts of 1 to 10 moles of ethylene oxide with octyl and nonylphenol in the form of their sodium and / or magnesium salts.
  • the ether sulfates can be used in the form of aqueous solutions with a solids content in the range from 5 to 75% by weight.
  • the solids content of the starting solutions is preferably from 60 to 70% by weight.
  • the content of 1,4-dioxane in the ether sulfate solutions to be purified can be 10 to 100 ppm and is typically 10 to 25 ppm, based on solutions with a solids content of 60 to 70% by weight.
  • the aqueous ether sulfate solutions are preferably heated to a temperature of 80 to 120 by continuously blowing in superheated water vapor by means of a continuous-intensive mixer of the rotor-stator type, for example in a Supraton or Cavitron 95 to 105 ° C heated.
  • a defoaming device consisting of an evacuable vessel (for example a cyclone) with a turntable and vacuum pump, applied to the turntable at a reduced pressure of 10 to 200 mbar, divided into fine droplets and via a second pump located at the outlet Plant continuously separated; the 1,4-dioxane and the other volatile impurities, for example ethylene oxide, propylene oxide or short-chain aldehydes, are removed together with the water vapor via the vacuum pump.
  • an evacuable vessel for example a cyclone
  • a turntable and vacuum pump applied to the turntable at a reduced pressure of 10 to 200 mbar, divided into fine droplets and via a second pump located at the outlet Plant continuously separated;
  • the 1,4-dioxane and the other volatile impurities for example ethylene oxide, propylene oxide or short-chain aldehydes
  • the apparatus for performing the method according to the invention is shown in Fig.l. It essentially consists of a feed pump (1), the intensive mixer (2), the evacuation vessel with a turntable (3), the draw-off pump (4) and the vacuum pump (5).
  • the aqueous ether sulfate solution is fed to the intensive mixer via the feed pump (1). Steam from 2 to 6 bar is introduced into the liquid flow through a pipe leading into the product line in front of the inlet connector of the intensive mixer and mixed intensively with the anionic surfactant solution in the mixer. As a result of this measure, the temperature of the solution rises to the optimum temperature of 80 to 120 ° C. for the separation of the 1,4-dioxane. At the same time, the ether sulfate solution is diluted by about 5% by weight, so that the water loss which occurs during evaporation in vacuo can be compensated for. Surprisingly, it was found that the temperature load of a maximum of 120 ° C.
  • both the optimal temperature for removing 1,4-dioxane and the desired solids concentration of the resulting ether sulfate solution can be set exactly.
  • the ether sulfate solution heated by means of direct steam then reaches the evacuation vessel (3) with a rotary dial.
  • This preferably has a perforated plate standing vertically at the edge, which is arranged in the form of a ring through which the solution is pressed and finely distributed due to the centrifugal effect of the turntable.
  • the droplet spectrum is independent of the throughput and has a narrow distribution.
  • the droplets collect in the conical lower part of the evacuation vessel.
  • the purified ether sulfate solution can then be separated off with the aid of a suitable pump without any further stirring device.
  • the ether sulfate solutions obtainable by the process according to the invention have an increased solids content, which is preferably between 60 and 75% by weight, and a significantly reduced content of 1,4-dioxane. Based on 10% by weight application concentrations of the aqueous ether sulfate solution, 1,4-dioxane contents of less than 1 ppm are reliably reached or undercut.
  • the ether sulfate solutions obtainable by the process according to the invention can be used to prepare top surface-active agents, in particular manual dishwashing agents and hair treatment agents are used, which in turn can be characterized as "dioxane-free".
  • a mass flow of 2,000 kg / h of an aqueous solution of a Ci2 / 14 ⁇ ⁇ ° ko s fatty alcohol-2EO sulfate sodium salt with a solids content of 68 wt .-% and a content of 1,4-dioxane of 20 ppm was introduced from 125 kg / h superheated 6 bar steam in an intensive mixer of the rotor-stator type to a temperature of 95 ° C. and placed on the turntable of a vacuum defoaming vessel; the vacuum was 65 mbar (see Fig. 1).
  • the product discharged had a solids content of 70% by weight and a 1,4-dioxane content of 6 ppm.
  • Example 1 was an aqueous using 2,000 kg / h

Abstract

Aqueous solutions of ether sulphate salts with a reduced 1,4 dioxane content are obtained if, continuously: a) an aqueous ether sulphate solution is heated to a temperature of 80 to 120 °C by the direct admixture of superheated steam in a circulation-intensive mixer of the rotor-stator type; b) the heated solution is passed to the turntable of an evacuated defoaming vessel; and c) the concentrated solution, largely freed of 1,4 dioxane, is separated out.

Description

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Verfahren zur Herstellung wäßriger» Lösungen von Ethersulfat-Salzen mit vermindertem Gehalt an 1,4-DioxanProcess for the preparation of aqueous solutions of ether sulfate salts with a reduced content of 1,4-dioxane
Gebiet der ErfindungField of the Invention
Die Erfindung betrifft ein Verfahren zur Herstellung wäßriger Lösungen von Ethersulfat-Salzen mit vermindertem Gehalt an 1,4-Dioxan, bei dem man die wäßrigen Lösungen zunächst mit überhitztem Wasserdampf behandelt und dann auf den Drehteller eines evakuierten Entschäumungsgefaßes aufgibt.The invention relates to a process for the preparation of aqueous solutions of ether sulfate salts with a reduced content of 1,4-dioxane, in which the aqueous solutions are first treated with superheated steam and then placed on the turntable of an evacuated defoaming vessel.
Stand der TechnikState of the art
Fettalkoholpolyglycolethersulfate und Alkylphenolpolyglycol- ethersulfate, die unter der Sammelbezeichnung "Ethersulfate" subsummiert werden, stellen anionische Tenside dar, die wegen intensiven Schaumvermögens, geringer Härteempfindlichkeit, guter Reinigungsleistung und vorteilhafter hautkosmetischer Verträglichkeit vielfach zur Herstellung von manuellen Ge¬ schirrspülmitteln, Haarbehandlungsmitteln und anderen ober¬ flächenaktiven Produkten verwendet werden, die mit der menschlichen Haut in Kontakt treten. Zur Herstellung der Ethersulfate geht man von den entspre¬ chenden Hydroxyverbindungen - vorzugsweise Fettalkoholen oder Alkylphenolen - aus, die zunächst mit Alkylenoxiden zu den Polyglycolethern umgesetzt, anschließend mit Schwefeltrioxid oder Chlorsulfonsäure sulfatiert und schließlich mit wäßrigen Basen neutralisiert werden. Ein Problem bei der Herstellung von Ethersulfaten stellt der Anteil an Verunreinigungen, ins¬ besondere an 1,4-Dioxan dar, der aus einem autokatalytischen Abbau der Polyglycoletherkette auf der Stufe der nichtneutra- lisierten Sulfatierungsprodukte resultiert. Die Gehalte lie¬ gen üblicherweise auch bei konzentrierten wäßrigen Ethersul- fat-Lösungen deutlich unter 100 ppm und sind in diesen Mengen wie eine Vielzahl von Studien belegen, toxikologisch unbe¬ denklich. Es besteht aber dennoch ein Marktbedürfnis nach Ethersulfaten mit weiter minimiertem Gehalt an 1,4-Dioxan. Insbesondere sind solche Produkte erwünscht, die in 10 Gew.- %iger Verdünnung weniger als 1 ppm 1,4-Dioxan enthalten und damit als "dioxanfrei" gekennzeichnet werden dürfen.Fatty alcohol polyglycol ether sulfates and alkylphenol polyglycol ether sulfates, which are subsumed under the collective name "ether sulfates", are anionic surfactants which, because of their intensive foaming power, low sensitivity to hardness, good cleaning performance and advantageous skin cosmetic tolerance, are often used to produce manual dishwashing detergents, other hair-treatment agents and other surface-active agents Products that come into contact with human skin are used. The preparation of the ether sulfates is based on the corresponding hydroxy compounds - preferably fatty alcohols or alkylphenols - which are first reacted with alkylene oxides to give the polyglycol ethers, then sulfated with sulfur trioxide or chlorosulfonic acid and finally neutralized with aqueous bases. A problem in the production of ether sulfates is the proportion of impurities, in particular 1,4-dioxane, which results from an autocatalytic degradation of the polyglycol ether chain at the stage of the non-neutralized sulfation products. The contents are usually well below 100 ppm even in the case of concentrated aqueous ether sulfate solutions and, as a large number of studies have shown, these amounts are toxicologically harmless. However, there is still a market need for ether sulfates with a further minimized 1,4-dioxane content. In particular, those products are desired which, in a 10% by weight dilution, contain less than 1 ppm 1,4-dioxane and can therefore be labeled as "dioxane-free".
In der Vergangenheit hat es eine Vielzahl von Versuchen ge¬ geben, das Problem der Dioxanbildung in Ethersulfaten zu verhindern bzw. zu minimieren.In the past there have been numerous attempts to prevent or minimize the problem of dioxane formation in ether sulfates.
So wird beispielsweise in der WO 91/05764 (Henkel) vorge¬ schlagen, Ethersulfate mit vermindertem Gehalt an 1,4-Dioxan herzustellen, indem man Fettalkoholpolyglycolether mit einer eingeengten Homologenverteilung (NRE = narrow ränge ethoxy- lates) einsetz . Die Herstellung von NRE-Polyglycolethern ist jedoch technisch aufwendig und kostspielig. In der US 4,285,881 (Conoco) wird ein Verfahren beschrieben, bei dem man 1,4-Dioxan aus Ethersulfatlösungen mit Wasser¬ dampf bei Temperaturen von 25 bis 150°C in einem Dünnschicht¬ verdampfer abtrennt. Gemäß der DE-Al 31 26 175 werden Ether- sulfat-Lösungen mit einem Feststoffgehalt von 60 bis 80 Gew.-% durch eine Wärmebehandlung bei 50 bis 130°C unter ver¬ mindertem Druck desodoriert, wobei auch 1,4-Dioxan entfernt wird. In der DE-Al 30 44 488 (Henkel) wird über ein Verfahren zur Erniedrigung des Dioxangehaltes in Ethersulfaten berich¬ tet, bei dem man zunächst Ethersulfat-Lösungen mit einem Feststoffgehalt von 50 bis 80 Gew.-% herstellt und aus diesen ein Azeotrop aus Wasser und 1,4-Dioxan verdampft. Gegenstand der DE-Al 34 47 867 (Henkel) ist ebenfalls ein Verfahren zur Abtrennung von 1,4-Dioxan aus Ethersulfaten, bei dem man die wäßrigen Lösungen in Gegenwart eines Siliconentschäumers bei 110°C mit Wasserdampf behandelt; ein ähnliches Verfahren ist auch aus der EP-Bl 0 283 862 (Henkel) bekannt. Die genannten Verfahren sind jedoch ohne Ausnahme mit einem hohen techni¬ schen Aufwand verbunden, wenig wirtschaftlich und in ihrem Ergebnis nicht immer zufriedenstellend.For example, WO 91/05764 (Henkel) proposes to produce ether sulfates with a reduced 1,4-dioxane content by using fatty alcohol polyglycol ethers with a narrow homolog distribution (NRE = narrow range ethoxylates). However, the production of NRE polyglycol ethers is technically complex and costly. US Pat. No. 4,285,881 (Conoco) describes a process in which 1,4-dioxane is separated from ether sulfate solutions with water vapor at temperatures from 25 to 150 ° C. in a thin film evaporator. According to DE-Al 31 26 175, ether sulfate solutions with a solids content of 60 to 80% by weight are deodorized by heat treatment at 50 to 130 ° C. under reduced pressure, 1,4-dioxane also being removed . DE-A1 30 44 488 (Henkel) reports on a process for reducing the dioxane content in ether sulfates, in which ether sulfate solutions with a solids content of 50 to 80% by weight are first prepared and an azeotrope is produced therefrom Water and 1,4-dioxane evaporated. DE-Al 34 47 867 (Henkel) also relates to a process for separating 1,4-dioxane from ether sulfates, in which the aqueous solutions are treated with steam at 110 ° C. in the presence of a silicone defoamer; a similar process is also known from EP-Bl 0 283 862 (Henkel). Without exception, the methods mentioned are associated with a high technical outlay, are not very economical and their results are not always satisfactory.
In der DE-C2 37 40 695 (Rewo) wird ein Verfahren zur Entfer¬ nung von 1,4-Dioxan beschrieben, bei dem man die Ethersulfat- Lösungen mit Zeolithen behandelt. Gemäß der Lehren der EP-AI 0 321 854 (Hoechst) bzw. EP-AI 0 377 916 (Stamicarbon) lassen sich Ethersulfate mit geringem Gehalt an 1,4-Dioxan erhalten, indem man die Sulfatierung der Polyglycolether in Gegenwart von ethoxylierten Fettsauramiden bzw. Thioharnstoff sowie anderen Aminverbindungen durchführt. In der EP-Bl 0327 007 (Hoechst) wird für den gleichen Zweck vorgeschlagen, den sauren Sulfatierungsprodukten vor der Neutralisation Wasser oder kurzkettige Alkohole zuzusetzen. Auf diesem Wege werden jedoch Mischungen von Ethersulfaten mit anderen Stoffen er¬ halten, die aus anwendungstechnischer Sicht unerwünscht sind.DE-C2 37 40 695 (Rewo) describes a process for removing 1,4-dioxane in which the ether sulfate solutions are treated with zeolites. According to the teachings of EP-AI 0 321 854 (Hoechst) and EP-AI 0 377 916 (Stamicarbon), ether sulfates with a low content of 1,4-dioxane can be obtained by sulfating the polyglycol ethers in the presence of ethoxylated fatty acid amides or Performs thiourea and other amine compounds. In EP-Bl 0327 007 (Hoechst) water is proposed for the same purpose, the acidic sulfation products before neutralization or add short chain alcohols. In this way, however, mixtures of ether sulfates with other substances are obtained which are undesirable from an application point of view.
Die Aufgabe der Erfindung hat somit darin bestanden, ein neues, kontinuierliches Verfahren zur Herstellung von wäßri¬ gen, hochkonzentrierten Lösungen von Ethersulfat-Salzen mit vermindertem Gehalt an 1,4-Dioxan zu entwickeln, das frei von den geschilderten Nachteilen ist.The object of the invention was therefore to develop a new, continuous process for the production of aqueous, highly concentrated solutions of ether sulfate salts with a reduced content of 1,4-dioxane, which is free from the disadvantages described.
Beschreibung der ErfindungDescription of the invention
Gegenstand der Erfindung ist ein Verfahren zur Herstellung wäßriger Lösungen von Ethersulfat-Salzen mit vermindertem Ge¬ halt an 1,4-Dioxan, bei dem man kontinuierlichThe invention relates to a process for the preparation of aqueous solutions of ether sulfate salts with a reduced content of 1,4-dioxane, in which process continuously
a) eine wäßrige Ethersulfat-Lösung durch direktes Zumischen von überhitztem Wasserdampf in einem Durchlauf-Intensiv- Mischer vom Rotor-Stator-Typ auf eine Temperatur von 80 bis 120°C erhitzt, b) die erhitzte Lösung auf den Drehteller eines evakuierten Entschäumungsgefaßes aufgibt und c) die aufkonzentrierte und von 1,4-Dioxan weitgehend be¬ freite Lösung abtrennt.a) an aqueous ether sulfate solution is heated to a temperature of 80 to 120 ° C by direct admixing of superheated steam in a continuous intensive mixer of the rotor-stator type, b) the heated solution is placed on the turntable of an evacuated defoaming vessel and c) the concentrated solution, which is largely freed of 1,4-dioxane, is separated off.
Überraschenderweise wurde gefunden, daß nach dem erfindungs¬ gemäßen Verfahren Ethersulfat-Lösungen erhalten werden, deren Gehalt an 1,4-Dioxan und anderen unerwünschten Verunreini¬ gungen, die z.B. auch Farbe und Geruch beeinträchtigen kön- nen, substanziell vermindert worden ist und die gleichzeitig einen erhöhten Feststoffanteil aufweisen.Surprisingly, it has been found that ether sulfate solutions are obtained by the process according to the invention, the content of 1,4-dioxane and other undesirable impurities which, for example, can also impair color and smell. NEN, has been substantially reduced and at the same time have an increased solids content.
EthersulfateEther sulfates
Unter dem Begriff Ethersulfate werden anionische Tenside sub- summiert, die eine anionische Sulfatgruppe in direkter Ver¬ bindung mit einer nichtionischen Polyglycoletherkette aufwei¬ sen und der Formel (I) folgen,The term ether sulfates is used to sum up anionic surfactants which have an anionic sulfate group in direct connection with a nonionic polyglycol ether chain and follow the formula (I),
CH3 I Rlθ-(CH2CH2θ)m(CH2CHO)nSθ3X f1)CH 3 I Rl θ - (CH 2 CH2 θ ) m (CH2CHO) n S θ 3X f 1 )
in der R1 für einen linearen oder verzweigten aliphatischen Kohlenwasserstoffreεt mit 6 bis 22 Kohlenstoffatomen und 0 und/oder 1 bis 3 Doppelbindungen oder einen Alkylphenylrest mit 6 bis 10 Kohlenstoff tomen im Alkylrest, m für Zahlen von 1 bis 20, n für Zahlen von 0 bis 20 und X für ein Alkali- und/oder Erdalkalimetall, Ammonium, Alkylammonium, Alkanol- ammonium oder Glucammonium steht.in which R 1 is a linear or branched aliphatic hydrocarbon radical having 6 to 22 carbon atoms and 0 and / or 1 to 3 double bonds or an alkylphenyl radical having 6 to 10 carbon atoms in the alkyl radical, m for numbers from 1 to 20, n for numbers from 0 to 20 and X represents an alkali and / or alkaline earth metal, ammonium, alkylammonium, alkanolammonium or glucammonium.
Typische Beispiele hierfür sind Fettalkoholethersulfate der Formel (I), in der R1 für einen Alkyl- und/oder Alkenylrest mit 6 bis 22, vorzugsweise 12 bis 18 Kohlenstoffatomen, m für Zahlen von 1 bis 10, n für 0 und X für Natrium oder Magnesium steht. Exemplarisch seien die Sulfate der Addukte von durch¬ schnittlich 1 bis 10, vorzugsweise 2 bis 5 Mol Ethylenoxid anTypical examples of these are fatty alcohol ether sulfates of the formula (I) in which R 1 is an alkyl and / or alkenyl radical having 6 to 22, preferably 12 to 18 carbon atoms, m is a number from 1 to 10, n is 0 and X is sodium or Magnesium stands. Examples are the sulfates of the adducts of on average 1 to 10, preferably 2 to 5, moles of ethylene oxide
Ci2/14~κ°kosfettalkohol, Ci2/18~Ko^cos^ettal^0*x°l unc c16/18~ Taigfettalkohol sowie die Addukte von durchschnittlich 2 bis 4 Mol Ethylenoxid an Cg/iQ-Vorlauffettalkohol oder Laurylal- kohol genannt. Die Fettalkoholethersulfate können dabei be¬ züglich ihrer Polyglycoletherkette sowohl eine konventionelle als auch eine eingeengte Homologenverteilung aufweisen.Ci2 / 14 ~ κ ° Kosfettalkohol, Ci2 / 18 ~ Ko ^ cos ^ etta l ^ 0 * x ° l unc c 16/18 ~ Taigfettalkohol as well as the adducts from 2 to 4 moles of ethylene oxide on Cg / i Q -flow fatty alcohol or lauryl alcohol called. The fatty alcohol ether sulfates can have both a conventional and a narrow homolog distribution with regard to their polyglycol ether chain.
Eine zweite Gruppe von Verbindungen, die unter den Begriff Ethersulfate fallen, stellen die Alkylarylethersulfate, ins¬ besondere die Alkylphenolethersulfate dar, wie etwa die Sul¬ fate der Anlagerungsprodukte von Ethylenoxid an Alkylphenole. Typische Beispiele sind die Sulfate der Addukte von 1 bis 10 Mol Ethylenoxid an Octyl- und Nonylphenol in Form ihrer Na¬ trium- und/oder Magnesiumsalze.A second group of compounds which come under the term ether sulfates are the alkylaryl ether sulfates, in particular the alkylphenol ether sulfates, such as the sulfates of the adducts of ethylene oxide with alkylphenols. Typical examples are the sulfates of the adducts of 1 to 10 moles of ethylene oxide with octyl and nonylphenol in the form of their sodium and / or magnesium salts.
Die Ethersulfate können in Form wäßriger Lösungen mit einem Feststoffgehalt im Bereich von 5 bis 75 Gew.-% eingesetzt werden. Vorzugsweise beträgt der Feststoffgehalt der Aus¬ gangslösungen jedoch 60 bis 70 Gew.-%. Der Gehalt an 1,4- Dioxan in den zu reinigenden Ethersulfat-Lösungen kann 10 bis 100 ppm betragen und liegt typischerweise - bezogen auf Lö¬ sungen mit einem Feststoffgehalt von 60 bis 70 Gew.-% - bei 10 bis 25 ppm.The ether sulfates can be used in the form of aqueous solutions with a solids content in the range from 5 to 75% by weight. However, the solids content of the starting solutions is preferably from 60 to 70% by weight. The content of 1,4-dioxane in the ether sulfate solutions to be purified can be 10 to 100 ppm and is typically 10 to 25 ppm, based on solutions with a solids content of 60 to 70% by weight.
Abtrennung von 1,4-DioxanSeparation of 1,4-dioxane
Zur Durchführung des erfindungsgemäßen Verfahrens werden die wäßrigen Ethersulfat-Lösungen durch kontinuierliches direktes Einblasen von überhitztem Wassrdfampf mittels eines Durch¬ lauf-Intensiv-Mischers vom Rotor-Stator-Typ, z.B. in einem Supraton oder Cavitron, auf eine Temperatur von 80 bis 120, vorzugsweise 95 bis 105°C erhitzt. Anschließend werden die so vorbehandelten Lösungen in einer Entschäumungseinrichtung, bestehend aus einem evakuierbaren Gefäß (z.B. einem Zyklon) mit Drehteller und Vakuumpumpe, bei einem verminderten Druck von 10 bis 200 mbar auf den Drehteller aufgegeben, in feine Tröpfchen zerteilt und über eine am Auslauf befindliche zwei¬ te Pumpe der Anlage kontinuierlich abgetrennt; das 1,4-Dioxan und die anderen flüchtigen Verunreinigungen, beispielsweise Ethylenoxid, Propylenoxid oder kurzkettige Aldehyde, werden dabei zusammen mit dem Wasserdampf über die Vakuumpumpe ent¬ fernt.To carry out the process according to the invention, the aqueous ether sulfate solutions are preferably heated to a temperature of 80 to 120 by continuously blowing in superheated water vapor by means of a continuous-intensive mixer of the rotor-stator type, for example in a Supraton or Cavitron 95 to 105 ° C heated. Then they are like this pretreated solutions in a defoaming device, consisting of an evacuable vessel (for example a cyclone) with a turntable and vacuum pump, applied to the turntable at a reduced pressure of 10 to 200 mbar, divided into fine droplets and via a second pump located at the outlet Plant continuously separated; the 1,4-dioxane and the other volatile impurities, for example ethylene oxide, propylene oxide or short-chain aldehydes, are removed together with the water vapor via the vacuum pump.
Die Apparatur zur Durchführung des erfindungsgemäßen Verfah¬ rens ist in Abb.l dargestellt. Sie besteht im wesentlichen aus einer Zulaufpumpe (1) , dem Intensiv-Mischer (2) , dem Eva¬ kuierungsgefäß mit Drehteller (3), der Abziehpumpe (4) und der Vakuumpumpe (5) .The apparatus for performing the method according to the invention is shown in Fig.l. It essentially consists of a feed pump (1), the intensive mixer (2), the evacuation vessel with a turntable (3), the draw-off pump (4) and the vacuum pump (5).
Über die Zulaufpumpe (1) wird die wäßrige Ethersulfat-Lösung dem Intensiv-Mischer zugeführt. Durch ein vor dem Einlauf- stutzen des Intensiv-Mischers in die Produktleitung führendes Rohr wird Dampf von 2 bis 6 bar in den Flüssigkeitsstrom ein¬ geleitet und im Mischer intensiv mit der Aniontensidlösung vermischt. Durch diese Maßnahme steigt die Temperatur der Lösung auf die für die Abtrennung des 1,4-Dioxans optimale Temperatur von 80 bis 120°C an. Gleichzeitig findet eine Verdünnung der Ethersulfatlösung um ca. 5 Gew.-% statt, so daß der bei der Verdampfung im Vakuum auftretende Wasserver¬ lust ausgeglichen werden kann. Überraschenderweise wurde ge- -funden, daß die auftretende Temperaturbelastung von maximal 120°C nicht zu einer Farbverschlechterung der Produkte führt. Durch Regelung der Produkttemperatur nach Verlassen des Mischers sowie des Druckes im Evakuierungsgefäß lassen sich sowohl die optimale Temperatur für die Entfernung des 1,4- Dioxans als auch die gewünschte Feststoffkonzentration der resultierenden Ethersulfat-Lösung exakt einstellen.The aqueous ether sulfate solution is fed to the intensive mixer via the feed pump (1). Steam from 2 to 6 bar is introduced into the liquid flow through a pipe leading into the product line in front of the inlet connector of the intensive mixer and mixed intensively with the anionic surfactant solution in the mixer. As a result of this measure, the temperature of the solution rises to the optimum temperature of 80 to 120 ° C. for the separation of the 1,4-dioxane. At the same time, the ether sulfate solution is diluted by about 5% by weight, so that the water loss which occurs during evaporation in vacuo can be compensated for. Surprisingly, it was found that the temperature load of a maximum of 120 ° C. does not lead to a deterioration in the color of the products. By regulating the product temperature after leaving the Mixer and the pressure in the evacuation vessel, both the optimal temperature for removing 1,4-dioxane and the desired solids concentration of the resulting ether sulfate solution can be set exactly.
Die mittels Direktdampf aufgeheizte Ethersulfat-Lösung ge¬ langt anschließend in das Evakuierungsgefäß (3) mit Drehtel¬ ler. Dieser verfügt vorzugsweise über ein am Rand befindli¬ ches senkrecht stehendes Lochblech, das in Form eines Kranzes angeordnet ist, durch das die Lösung aufgrund der Schleuder¬ wirkung des Drehtellers gedrückt und fein verteilt wird. Das anfallende Tröpchenspektrum ist von der Durchsatzleistung unabhängig und besitzt eine enge Verteilung. Die Tröpfchen sammeln sich im konischen Unterteil des Evakuierungsgefäßes. Die gereinigte Ethersulfat-Lösung anschließend kann ohne weitere Rühreinrichtung mit Hilfe einer geeigneten Pumpe ab¬ getrennt werden.The ether sulfate solution heated by means of direct steam then reaches the evacuation vessel (3) with a rotary dial. This preferably has a perforated plate standing vertically at the edge, which is arranged in the form of a ring through which the solution is pressed and finely distributed due to the centrifugal effect of the turntable. The droplet spectrum is independent of the throughput and has a narrow distribution. The droplets collect in the conical lower part of the evacuation vessel. The purified ether sulfate solution can then be separated off with the aid of a suitable pump without any further stirring device.
Gewerbliche AnwendbarkeitIndustrial applicability
Die nach dem erfindungsgemäßen Verfahren erhältlichen Ether¬ sulfat-Lösungen weisen einen erhöhten Feststoffgehalt, der vorzugsweise zwischen 60 und 75 Gew.-% liegt, und einen sig¬ nifikant verminderten Gehalt an 1,4-Dioxan auf. Bezogen auf 10 Gew.-%ige Anwendungskonzentrationen der wäßrigen Ether¬ sulfatlösung werden 1,4-Dioxangehalte von weniger als 1 ppm zuverlässig erreicht bzw. unterschritten.The ether sulfate solutions obtainable by the process according to the invention have an increased solids content, which is preferably between 60 and 75% by weight, and a significantly reduced content of 1,4-dioxane. Based on 10% by weight application concentrations of the aqueous ether sulfate solution, 1,4-dioxane contents of less than 1 ppm are reliably reached or undercut.
Demnach können die nach dem erfindungsgemäßen Verfahren er¬ hältlichen Ethersulfat-Lösungen zur Herstellung von ober- flächenaktiven Mitteln, insbesondere manuellen Geschirrspül¬ mitteln und Haarbehandlungsmitteln eingesetzt werden, die ihrerseits als "dioxanfrei" gekennzeichnet werden können.Accordingly, the ether sulfate solutions obtainable by the process according to the invention can be used to prepare top surface-active agents, in particular manual dishwashing agents and hair treatment agents are used, which in turn can be characterized as "dioxane-free".
Die folgenden Beispiele sollen den Gegenstand der Erfindung näher erläutern, ohne ihn darauf einzuschränken. The following examples are intended to explain the subject matter of the invention in more detail without restricting it.
BeispieleExamples
Beispiel 1:Example 1:
Ein Mengenstrom von 2.000 kg/h einer wäßrigen Lösung eines Ci2/14~κ°kosfettalkohol-2EO-sulfat-Natriumsalzes mit einem Feststoffgehalt von 68 Gew.-% und einem Gehalt an 1,4-Dioxan von 20 ppm wurde unter Einleitung von 125 kg/h überhitztem 6- bar-Dampf in einem Intensivmischer vom Rotor-Stator-Typ auf eine Temperatur von 95°C gebracht und auf den Drehteller ei¬ nes Vakuumentschäumenungsgefäßeε aufgegeben; das Vakuum be¬ trug 65 mbar (vgl.Abb.l) . Das ausgetragene Produkt wies einen Feststoffgehalt von 70 Gew.-% und einen Gehalt an 1,4-Dioxan von 6 ppm auf.A mass flow of 2,000 kg / h of an aqueous solution of a Ci2 / 14 ~ κ ° ko s fatty alcohol-2EO sulfate sodium salt with a solids content of 68 wt .-% and a content of 1,4-dioxane of 20 ppm was introduced from 125 kg / h superheated 6 bar steam in an intensive mixer of the rotor-stator type to a temperature of 95 ° C. and placed on the turntable of a vacuum defoaming vessel; the vacuum was 65 mbar (see Fig. 1). The product discharged had a solids content of 70% by weight and a 1,4-dioxane content of 6 ppm.
Beispiel 2tExample 2t
Beispiel 1 wurde unter Einsatz von 2.000 kg/h einer wäßrigenExample 1 was an aqueous using 2,000 kg / h
Lösung eines Ci2/14-κ°k°sfettalkohol-3,6-EO-Natriumsalzes πάt einem Feststoffgehalt von 65 Gew.-% und einem Gehalt an 1,4-Solution of a Ci2 / 14- κ ° k ° s f etta alcohol-3,6-EO sodium salt πάt with a solids content of 65 wt .-% and a content of 1,4-
Dioxan von 17 ppm wiederholt. Das ausgetragene Produkt wies einen Feststoffgehalt von 68 Gew.-% und einen Gehalt an 1,4- Dioxan von 3 ppm auf. Repeated dioxane of 17 ppm. The product discharged had a solids content of 68% by weight and a 1,4-dioxane content of 3 ppm.

Claims

PatentansprücheClaims
Verfahren zur Herstellung wäßriger Lösungen von Ether¬ sulfat-Salzen mit vermindertem Gehalt an 1,4-Dioxan, bei dem man kontinuierlichProcess for the preparation of aqueous solutions of ether sulfate salts with a reduced content of 1,4-dioxane, in which process
a) eine wäßrige Ethersulfat-Lösung durch direktes Zu¬ mischen von überhitztem Wasserdampf in einem Durchlauf-Intensiv-Mischer vom Rotor-Stator-Typ auf eine Temperatur von 80 bis 120°C erhitzt, b) die erhitzte Lösung auf den Drehteller eines eva¬ kuierten Entschäumungsgefaßes aufgibt und c) die aufkonzentrierte und von 1,4-Dioxan weitgehend befreite Lösung abtrennt.a) an aqueous ether sulfate solution is heated to a temperature of 80 to 120 ° C. by directly admixing superheated steam in a continuous intensive mixer of the rotor-stator type, b) the heated solution is placed on the turntable of an eva¬ gives up the defoaming vessel and c) separates the concentrated and largely freed of 1,4-dioxane solution.
Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß man wäßrige Lösungen von Ethersulfaten der Formel (I) einsetzt,Process according to Claim 1, characterized in that aqueous solutions of ether sulfates of the formula (I) are used,
CH3 I Rlθ-(CH2CH2θ)m(CH2CHO)nSθ3X (*)CH 3 I Rlθ- (CH 2 CH2 θ ) m (CH2CHO) n S θ 3X (*)
in der R1 für einen linearen oder verzweigten aliphati- schen Kohlenwasserstoffrest mit 6 bis 22 Kohlenstoff¬ atomen und 0 und/oder 1 bis 3 Doppelbindungen oder einen Alkylphenylrest mit 6 bis 10 Kohlenstoffatomen im Alkylrest, m für Zahlen von 1 bis 20, n für Zahlen von 0 bis 20 und X für ein Alkali- und/oder Erdalkalimetall, Ammonium, Alkylammonium, Alkanolammonium oder Glucammo- nium steht. 3. Verfahren nach den Ansprüchen 1 und 2, dadurch gekenn¬ zeichnet, daß man wäßrige Lösungen von Ethersulfaten mit einem Feststoffgehalt im Bereich von 5 bis 75 Gew.-% einsetzt.in R 1 for a linear or branched aliphatic hydrocarbon radical with 6 to 22 carbon atoms and 0 and / or 1 to 3 double bonds or an alkylphenyl radical with 6 to 10 carbon atoms in the alkyl radical, m for numbers from 1 to 20, n for Numbers from 0 to 20 and X represents an alkali and / or alkaline earth metal, ammonium, alkylammonium, alkanolammonium or glucammonium. 3. Process according to claims 1 and 2, characterized gekenn¬ characterized in that aqueous solutions of ether sulfates are used with a solids content in the range of 5 to 75 wt .-%.
4. Verfahren nach den Ansprüchen 1 bis 3, dadurch gekenn¬ zeichnet, daß man wäßrige Lösungen von Ethersulfaten mit einem Gehalt an 1,4-Dioxan von 10 bis 100 ppm einsetzt.4. Process according to claims 1 to 3, characterized gekenn¬ characterized in that aqueous solutions of ether sulfates containing 1,4-dioxane from 10 to 100 ppm are used.
5. Verfahren nach den Ansprüchen 1 bis 4, dadurch gekenn¬ zeichnet, daß man die wäßrige Lösung bei einem vermin¬ derten Druck von 10 bis 200 mbar auf den Drehteller aufgibt. 5. The method according to claims 1 to 4, characterized gekenn¬ characterized in that the aqueous solution is given at a reduced pressure of 10 to 200 mbar on the turntable.
PCT/EP1994/003793 1993-11-23 1994-11-14 Process for producing aqueous solutions of ether sulphate salts with a reduced 1,4 dioxane content WO1995014660A1 (en)

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WO2014058791A1 (en) * 2012-10-08 2014-04-17 The Chemithon Corporation Process for removing dioxane from a composition
US8865928B2 (en) 2012-10-08 2014-10-21 The Chemithon Corporation Process for removing dioxane from a composition

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DE19840247B4 (en) * 1997-09-03 2015-10-08 Kao Corp. Process for the preparation of an anionic surfactant slurry
WO2014072840A1 (en) * 2012-11-12 2014-05-15 Galaxy Surfactants Ltd. Flowable, high active, aqueous fatty alkyl sulfates

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WO2014058791A1 (en) * 2012-10-08 2014-04-17 The Chemithon Corporation Process for removing dioxane from a composition
US8865928B2 (en) 2012-10-08 2014-10-21 The Chemithon Corporation Process for removing dioxane from a composition
KR20150067176A (en) * 2012-10-08 2015-06-17 더 케미톤 코포레이션 Process for removing dioxane from a composition
CN104718277A (en) * 2012-10-08 2015-06-17 剑米索恩公司 Process for removing dioxane from a composition
JP2015535852A (en) * 2012-10-08 2015-12-17 ザ・ケミソン・コーポレイション Method for removing dioxane from a composition
CN104718277B (en) * 2012-10-08 2018-11-16 剑米索恩公司 Method for removing dioxane from composition
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