WO1993021362A2 - Concentrate for the preparation of metal mordants - Google Patents

Concentrate for the preparation of metal mordants Download PDF

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Publication number
WO1993021362A2
WO1993021362A2 PCT/EP1993/000906 EP9300906W WO9321362A2 WO 1993021362 A2 WO1993021362 A2 WO 1993021362A2 EP 9300906 W EP9300906 W EP 9300906W WO 9321362 A2 WO9321362 A2 WO 9321362A2
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WO
WIPO (PCT)
Prior art keywords
water
acid
concentrate
compound
nitrate
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Application number
PCT/EP1993/000906
Other languages
German (de)
French (fr)
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WO1993021362A3 (en
Inventor
Rolf Spiekermann
Norbert Scheer
Original Assignee
Metasco Chemisch-Technische Produkte Gmbh
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
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Publication date
Application filed by Metasco Chemisch-Technische Produkte Gmbh filed Critical Metasco Chemisch-Technische Produkte Gmbh
Priority to EP93908942A priority Critical patent/EP0589028B1/en
Priority to DE59301633T priority patent/DE59301633D1/en
Publication of WO1993021362A2 publication Critical patent/WO1993021362A2/en
Publication of WO1993021362A3 publication Critical patent/WO1993021362A3/en

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
    • C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
    • C23G1/02—Cleaning or pickling metallic material with solutions or molten salts with acid solutions
    • C23G1/08—Iron or steel
    • C23G1/086—Iron or steel solutions containing HF
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
    • C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
    • C23G1/02—Cleaning or pickling metallic material with solutions or molten salts with acid solutions

Definitions

  • the invention relates to a solid concentrate for the production of an acidic aqueous pickling agent for metal surfaces and its use in the form of portion packs for the production of a defined amount of pickling agent.
  • metal surfaces e.g. made of steel and / or aluminum and their alloy
  • unsightly and corrosion-demanding oxide layers such as those e.g. in the heat treatment of metals (welding) or caused by the influence of the environment.
  • acid solutions for example based on hydrochloric acid, sulfuric acid, phosphoric acid or hydrofluoric acid.
  • Acidic pastes can also be applied to the areas to be cleaned, especially for large parts or local oxide formation. This dissolves part of the oxides and the base metal attached to them, so that the oxides lose their adhesion to the metal surface. After an appropriate time, they are rinsed off with water or removed by brushing.
  • Such a pickling or rust removal paste based on phosphoric acid contains e.g. as a thickener, saponifiable oil or a fatty acid that can be converted into soap (DE-AS 10 82 475).
  • Another known cleaning and etching agent consists of hydrofluoric acid, a magnesium compound, at least one acid from the group of nitric acid, phosphoric acid and sulfuric acid in the form of free acid or in the form -2-
  • pickling and rust removal pastes have been proposed which, in addition to fluoride ions, contain a mixture of compounds of calcium and trivalent iron and / or aluminum and have an acidity corresponding to at least 10% by weight of free acid (calculated as 100% HF) ( DE-OS 31 05 508).
  • Such pickling pastes are primarily intended for the treatment of alloyed steels.
  • the object of the invention is to take suitable measures for formulating pickling agents with which the known, in particular the aforementioned disadvantages are eliminated and which in particular solve the transport problem.
  • the object is achieved by formulating the mordant as a solid concentrate, the components of which are solid, water- and / or acid-soluble
  • magnesium compound or b2) calcium and / or aluminum compound and possibly
  • solid agents suitable for the production of pickling baths for stainless steel and the like consist of soluble inorganic fluoride, soluble phosphate and optionally organic base and are added in such quantities of dilute nitric acid that pickling baths of a certain fluoride concentration are formed (DE- B-1546138).
  • these are not solid pickling agent concentrates in the strict sense, i.e. concentrates that only need water as a solvent or dispersant. Because of the need to dissolve the solid agent in nitric acid, the problem of transporting aggressive liquids ultimately remains unsolved.
  • the solid concentrate according to the invention does not contain any ineffective sorbents, and at most water is required as an auxiliary to prepare the mordant.
  • the formulation of the concentrate components with a), bl) or b2) and optionally c) chosen above is intended to clarify that in addition to components a) and optionally c) either component bl) or component b2) is present. This does not rule out the fact that minor amounts of calcium and / or aluminum compound, or minor amounts of magnesium compound when component b2 is used, may be present in the mordant. If component b2 is present, calcium and aluminum compounds can of course be used together.
  • the fluoride is introduced as an acid salt with component a), it simultaneously represents a compound in component c) which is acidic in water, so that a separate addition of a compound which is acidic in water may be unnecessary.
  • the concentrate contains, in addition to a f bl or b2 and optionally c, as an additional component d) solid, water- and / or acid-soluble oxidizing agent.
  • oxidizing agent content causes a higher aggressiveness of the pickling agent and thus an accelerated dissolution or detachment of rust and scale and possibly increases the metal removal.
  • Another advantageous embodiment of the invention provides for the concentrate to be formulated with component bl.
  • the use of magnesium compound leads to a better thickening in the preparation of the mordant than the use of component b2, ie than the use of calcium and / or aluminum compound.
  • a concentrate is particularly advantageous
  • the free acid content to be set depends essentially on the aim pursued by the pickling process. If removal or dissolution of thin layers of scale is required, contents of 3.5% by weight (calculated as HF) or slightly more are sufficient. However, if thick layers of scale are to be removed or a certain metal removal is intended, the free acid content should be at least 10% by weight HF. If the concentrate according to the invention contains solid, water- and / or acid-soluble oxidizing agent (component d) according to the aforementioned preferred embodiment, a dimensioning which leads to a content of 1 to 10% by weight in the concentrate is particularly advantageous. As a rule, when using weak oxidizing agents, the content is in the upper range, when using strong oxidizing agents in the lower range mentioned above.
  • Further preferred embodiments of the invention consist of using permanganate and / or peroxide, in particular peroxydisulfate and / or carbamide peroxide, as component d). These substances are characterized by a particularly high effectiveness and also have the advantage of considerable resistance - even when mixed with the other components of the concentrate.
  • the concentrate should be the component
  • the individual components of the concentrate are mixed thoroughly. In order to prevent segregation of the individual components - especially during transport - it is advisable to use them with the same and expediently small particle size.
  • the shelf life of the concentrate according to the invention depends essentially on the crystal water content of the components used. When using largely water-free components, it is at least one month.
  • the shelf life can be increased considerably if, in accordance with a particular embodiment of the invention, the components containing water of crystallization and those free of water of crystallization are kept separate, i.e. only crystal water-containing and crystal water-free components are mixed with each other (if several substances of one type or another are used at all).
  • a certain disadvantage of the aforementioned separation is, however, that two doses have to be carried out to produce the mordant.
  • a special case of the present invention with separate keeping of only crystal water-free and only crystal water-containing components of the pickling agent, in which the crystal water-containing component has a relatively large amount of crystal water, consists in applying a pickling paste without additional use of water.
  • one of the two components brings the amount of water required to form the pickling paste in a chemically bound form.
  • a particularly advantageous, user-oriented embodiment of the invention which also eliminates the aforementioned disadvantage of the need for double dosing, consists in using the concentrate in the form of portion packs for the production of defined amounts of mordant.
  • the packaged portions can be graduated to different sizes and can be used, for example, to produce 1, 2, 5 or 10 1 pickling agents. This applies equally to the case of the separation of concentrate components containing water of crystallization and water free of water of crystallization, in which case the contents of two packs in each case must be dissolved and / or dispersed in water.
  • the concentrate is mixed with water, the amount of water depending in particular on the desired viscosity of the mordant and this in turn on the form of application, for example by spraying or brushing.
  • the amount of water required to produce the mordant can be up to 60% by weight (based on the finished mordant).
  • the pickling agent is expediently produced using a stirrer until homogeneous distribution. Depending on the amount of mordant to be produced and the mixing intensity of the stirrer, the required stirring times are between about 1 and 5 minutes.
  • the pickling agent was produced from two separate solid substances I and II.
  • Substance I consisted of ammonium hydrogen fluoride (NH.HF,)
  • substance II consisted of a mixture of magnesium nitrate (Mg (N0 3 ) 2 «6H 2 0) and potassium nitrate (KN0 3 ) in a weight ratio of 2: 1.
  • the pickling agent was again produced from two separate substances I and II.
  • Substance I was a mixture of ammonium hydrogen fluoride (NH.HF «) and ammonium peroxydisulfate ((NH 4 ) -S_0 8 ) in a weight ratio of 3.5: 1, substance II one Mixture of magnesium nitrate (Mg (N0 _) _ «6H_0) and potassium nitrate (KN0_) in a weight ratio of 2: 1.

Abstract

A solid concentrate used to prepare an acid aqueous mordant for metal surfaces contains solid, water-and/or acid-solulble (a) fluoride and nitrate compounds, preferably as an alkali and/or ammonium salt; (b) magnesium compounds, preferably as nitrate, sulphate and/or citrate salts, or (b2) calcium and/or aluminium compounds, preferably as nitrate and/or citrate salt, and possibly (c) an in water acid-reacting compound, preferably as citric acid, amidosulphuric acid and/or alkali/ammonium dihydrogen phosphate. In a preferred embodiment, the concentrate may further contain a solid, water- and/or acid-soluble oxidizing agent. It is particularly appropriate to keep the components that contain constitutional water apart from constitutional water-free components. The concentrate may be made available for use as portion packages for preparing a defined amount of mordant.

Description

BESCHREIBUNG DESCRIPTION
Konzentrat zur Herstellung von MetallbeizmittelnConcentrate for the manufacture of metal mordants
Die Erfindung betrifft ein festes Konzentrat zur Herstellung eines sauren wässrigen Beizmittels für Metalloberflächen sowie dessen Anwendung in Form von Portionspackungen zur Herstellung einer definierten Beizmittelmenge.The invention relates to a solid concentrate for the production of an acidic aqueous pickling agent for metal surfaces and its use in the form of portion packs for the production of a defined amount of pickling agent.
Es ist üblich, von Metalloberflächen, z.B. aus Stahl und/oder Aluminium und deren Legierung, unansehnliche und korrosionsfordernde Oxidschichten, wie sie z.B. bei der Wärmebehandlung von Metallen (Schweißen) oder durch Einwirkung der Umgebung entstehen, zu beseitigen. Dies geschieht überwiegend mit Säurelösungen beispielsweise auf Basis Salzsäure, Schwefelsäure, Phosphorsäure oder auch Flußsäure.It is common for metal surfaces, e.g. made of steel and / or aluminum and their alloy, unsightly and corrosion-demanding oxide layers, such as those e.g. in the heat treatment of metals (welding) or caused by the influence of the environment. This is mainly done with acid solutions, for example based on hydrochloric acid, sulfuric acid, phosphoric acid or hydrofluoric acid.
Insbesondere bei großen Teilen oder örtlicher Oxidbildung können auf die zu reinigenden Stellen auch säurehaltige Pasten aufgebracht werden. Dadurch wird ein Teil der Oxide und das mit ihnen verhaftete Grundmetall aufgelöst, so daß die Oxide die Haftung zur Metalloberfläche verlieren. Sie werden nach angemessener Zeit mit Wasser abgespült bzw. durch Bürsten entfernt.Acidic pastes can also be applied to the areas to be cleaned, especially for large parts or local oxide formation. This dissolves part of the oxides and the base metal attached to them, so that the oxides lose their adhesion to the metal surface. After an appropriate time, they are rinsed off with water or removed by brushing.
Eine derartige Beiz- oder Entrostungspaste auf Basis Phosphorsäure enthält z.B. als Verdickungsmittel verseifbares Öl oder eine in Seife überführbare Fettsäure (DE-AS 10 82 475) .Such a pickling or rust removal paste based on phosphoric acid contains e.g. as a thickener, saponifiable oil or a fatty acid that can be converted into soap (DE-AS 10 82 475).
Ein anderes bekanntes Reinigungs- und Ätzmittel besteht aus Flußsäure, einer Magnesiumverbindung, mindestens einer Säure aus der Gruppe Salpetersäure, Phosphorsäure und Schwefelsäure in Form von freier Säure oder in Form -2-Another known cleaning and etching agent consists of hydrofluoric acid, a magnesium compound, at least one acid from the group of nitric acid, phosphoric acid and sulfuric acid in the form of free acid or in the form -2-
ihrer Salze sowie einer bestimmten Sulfonsäure (DE-AS 19 59 560) .their salts and a certain sulfonic acid (DE-AS 19 59 560).
Schließlich sind Beiz- und Entrostungspasten vorgeschlagen worden, die neben Fluoridionen eine Mischung von Verbindungen des Calciums sowie des dreiwertigen Eisens und/oder Aluminiums enthalten und eine Acidität entsprechend wenigstens 10% Gew.-% freier Säure (berechnet als 100%iges HF) aufweist (DE-OS 31 05 508) . Derartige Beizpasten sind vornehmlich zur Behandlung von legierten Stählen vorgesehen.Finally, pickling and rust removal pastes have been proposed which, in addition to fluoride ions, contain a mixture of compounds of calcium and trivalent iron and / or aluminum and have an acidity corresponding to at least 10% by weight of free acid (calculated as 100% HF) ( DE-OS 31 05 508). Such pickling pastes are primarily intended for the treatment of alloyed steels.
Obgleich sich insbesondere die Beiz- und Entrostungpasten der letztgenannten Art bewährt haben, haftet ihnen insofern ein Nachteil an, als zum Transport aufwendige Verpackungen erforderlich sind. Sie müssen säurebeständig sowie bruch- und reißfest sein, und zwar bei tiefen wie bei hohen Temperaturen. Ein besonderes Problem besteht häufig auch darin, daß derartige Beizmittel zur Entwicklung von korrosiven und gesundheitsgefährdenden Dämpfen neigen.Although in particular the pickling and rust removal pastes of the latter type have proven themselves, they have a disadvantage in that complex packaging is required for transport. They must be acid-resistant, break-proof and tear-resistant, both at low and high temperatures. A particular problem is often that such mordants tend to develop corrosive and health-endangering vapors.
Aufgabe der Erfindung ist es, geeignete Maßnahmen zur Formulierung von Beizmitteln zu ergreifen, mit denen die bekannten, insbesondere vorgenannten Nachteile behoben werden und die insbesondere das Transportproblem lösen.The object of the invention is to take suitable measures for formulating pickling agents with which the known, in particular the aforementioned disadvantages are eliminated and which in particular solve the transport problem.
Die Aufgabe wird gelöst, indem das Beizmittel als festes, Konzentrat formuliert wird, das als Komponenten jeweils feste, wasser- und/oder säurelöslicheThe object is achieved by formulating the mordant as a solid concentrate, the components of which are solid, water- and / or acid-soluble
a) Fluorid- und Nitratverbindung,a) fluoride and nitrate compound,
bl) Magnesiumverbindung oder b2) Kalzium- und/oder Aluminiumverbindung sowie ggf.bl) magnesium compound or b2) calcium and / or aluminum compound and possibly
c) in Wasser sauer reagierende Verbindungc) Acid-reacting compound in water
enthält.contains.
Zwar ist es bekannt, die eigentlich beizwirksamen Bestandteile von Beizmitteln in Pulverform zu überführen, indem sie an poröse, wasserfreie Silikate wie kalzinierter Perlit oder Zeolith sorptiv gebunden werden (JP-A-86-162599) , jedoch sind hierfür beträchtliche Mengen an Silikaten erforderlich, die letztlich lediglich einen Ballaststoff darstellen. Auςh lassen sich bestimmte, insbesondere Fluorwasserstoff enthaltende Beizmittel auf diese Weise nicht in Pulverform überführen.Although it is known to convert the actually active ingredients of pickling agents into powder form by sorptively binding them to porous, anhydrous silicates such as calcined perlite or zeolite (JP-A-86-162599), this requires considerable amounts of silicates, which are ultimately just a fiber. In addition, certain mordants, in particular those containing hydrogen fluoride, cannot be converted into powder form in this way.
Weiterhin sind feste, zur Herstellung von Beizbädern für nichtrostenden Stahl und dergl. geeignete Mittel bekannt, die aus löslichem anorganischen Fluorid, löslichem Phosphat und ggf. organischer Base bestehen und in solchen Mengen verdünnter Salpetersäure zugesetzt werden, daß Beizbäder einer bestimmten Fluoridkonzentration entstehen (DE-B-1546138) . Hierbei handelt es sich jedoch nicht tun feste Beizmittelkonzentrate im eigentlichen Sinn, d.h. um Konzentrate, die lediglich Wasser als Lösungs- oder Dispergiermittel benötigen. Wegen der Notwendigkeit, das feste Mittel in Salpetersäure lösen zu müssen, bleibt das Problem des Transportes agressiver Flüssigkeiten letztlich ungelöst.Furthermore, solid agents suitable for the production of pickling baths for stainless steel and the like are known which consist of soluble inorganic fluoride, soluble phosphate and optionally organic base and are added in such quantities of dilute nitric acid that pickling baths of a certain fluoride concentration are formed (DE- B-1546138). However, these are not solid pickling agent concentrates in the strict sense, i.e. concentrates that only need water as a solvent or dispersant. Because of the need to dissolve the solid agent in nitric acid, the problem of transporting aggressive liquids ultimately remains unsolved.
Demgegenüber enthält das erfindungsgemäße feste Konzentrat keine beizunwirksamen Sorptionsmittel, und zum Ansatz des Beizmittels bedarf es allenfalls Wasser als Hilfsstoff. -4-In contrast, the solid concentrate according to the invention does not contain any ineffective sorbents, and at most water is required as an auxiliary to prepare the mordant. -4-
Die vorstehend gewählte Formulierung der Konzentratkomponenten mit a) , bl) oder b2) und ggf. c) soll klarstellen, daß neben den Komponenten a) und ggf. c) entweder Komponente bl) oder Komponente b2) vorhanden ist. Das schließt nicht aus, daß bei Verwendung der Komponente bl untergeordnete Mengen an Kalzium- und/oder Aluminiumverbindung, bzw. bei Verwendung der Komponente b2 untergeordnete Mengen an Magnesiumverbindung im Beizmittel vorhanden sein dürfen. Im Fall der Gegenwart von Komponente b2 können selbstverständlich Kalzium- und Aluminiumverbindungen gemeinsam eingesetzt werden.The formulation of the concentrate components with a), bl) or b2) and optionally c) chosen above is intended to clarify that in addition to components a) and optionally c) either component bl) or component b2) is present. This does not rule out the fact that minor amounts of calcium and / or aluminum compound, or minor amounts of magnesium compound when component b2 is used, may be present in the mordant. If component b2 is present, calcium and aluminum compounds can of course be used together.
Sofern mit der Komponente a) das Fluorid als saures Salz eingebracht wird, stellt sie gleichzeitig eine in Wasser sauer reagierende Verbindung gemäß Komponente c) dar, so daß eine gesonderte Zugabe von in Wasser sauer reagierender Verbindung entbehrlich sein kann.If the fluoride is introduced as an acid salt with component a), it simultaneously represents a compound in component c) which is acidic in water, so that a separate addition of a compound which is acidic in water may be unnecessary.
Gemäß einer bevorzugten Ausgestaltung der Erfindung enthält das Konzentrat neben af bl oder b2 und ggf. c als zusätzliche Komponente d) festes, wasser- und/oder säurelösliches Oxidationsmittel. Der Oxidationsmittelgehalt bewirkt eine höhere Aggressivität des Beizmittels und damit eine beschleunigte Auf- bzw. Ablösung von Rost und Zunder und erhöht gegebenenfalls den Metallabtrag.According to a preferred embodiment of the invention, the concentrate contains, in addition to a f bl or b2 and optionally c, as an additional component d) solid, water- and / or acid-soluble oxidizing agent. The oxidizing agent content causes a higher aggressiveness of the pickling agent and thus an accelerated dissolution or detachment of rust and scale and possibly increases the metal removal.
Eine weitere vorteilhafte Ausführungsform der Erfindung sieht vor, das Konzentrat mit der Komponente bl zu formulieren. Der Einsatz von Magnesiumverbindung führt bei der Herstellung des Beizmittels zu einer besseren Eindickung als die Verwendung der Komponente b2, d.h. als die Verwendung von Kalzium- und/oder Aluminiumverbindung. Besonders vorteilhaft ist ein Konzentrat, dasAnother advantageous embodiment of the invention provides for the concentrate to be formulated with component bl. The use of magnesium compound leads to a better thickening in the preparation of the mordant than the use of component b2, ie than the use of calcium and / or aluminum compound. A concentrate is particularly advantageous
a) Fluoridverbindung in einer Menge von 14 bis 50 Gew.-% (ber. als F) , Nitratverbindung in einer Menge von 10 bis 50 Gew.-% (ber. als N03) ,a) fluoride compound in an amount of 14 to 50% by weight (calculated as F), nitrate compound in an amount of 10 to 50% by weight (calculated as N0 3 ),
bl) Magnesiumverbindung in einer Menge von 1 bis 7 Gew.-% (ber. als Mg) ,bl) magnesium compound in an amount of 1 to 7% by weight (calculated as Mg),
b2) Kalzium- und/oder Aluminiumverbindung in einer Menge von jeweils 1,5 bis 5 Gew.-% (ber. als Ca bzw. AI) , wobei bei Einsatz von Ca- und AI-Verbindung die Summe der Anteile 4 bis 9 Gew.-% beträgt,b2) calcium and / or aluminum compound in an amount of 1.5 to 5 wt .-% (calc. as Ca or Al), with the use of Ca and Al compound, the sum of the proportions 4 to 9 wt .-%,
c) sauer reagierende Verbindungen in einer Menge, daß im mit Wasser angesetzten Beizmittel ein Gehalt an freier Säure entsprechend mindestens 3,5 Gew.-% HF resultiert,c) acid-reacting compounds in an amount such that a free acid content corresponding to at least 3.5% by weight HF results in the mordant added to water,
enthält. Unter den vorgenannten Bedingungen resultiert ein Beizmittel, das bei günstiger Beizwirkung besonders gut applizierbar ist.contains. Under the aforementioned conditions, a pickling agent results which can be applied particularly well with a favorable pickling effect.
Der einzustellende Gehalt an freier Säure richtet sich im wesentlichen nach dem mit dem Beizprozeß verfolgten Ziel. Sofern ein Abtrag bzw. Auflösen von dünnen Zunderschichten erforderlich ist, sind Gehalte von 3,5 Gew.-% (ber. als HF) oder geringfügig mehr ausreichend. Sind jedoch dicke Zunderschichten zu entfernen oder ist ein gewisser Metallabtrag beabsichtigt, sollte der Gehalt an freier Säure entsprechend mindestens 10 Gew.-% HF sein. Sofern das erfindungsgemäße Konzentrat entsprechend der vorgenannten bevorzugten Ausgestaltung festes, wasser- und/oder säurelösliches Oxidationsmittel enthält (Komponente d) , ist besonders vorteilhaft eine Bemessung, die zu einem Gehalt von 1 bis 10 Gew.-% im Konzentrat führt. In der Regel liegt bei Verwendung schwacher Oxidationsmittel der Gehalt im oberen Bereich, bei Verwendung starker Oxidationsmittel im unteren vorgenannten Bereich.The free acid content to be set depends essentially on the aim pursued by the pickling process. If removal or dissolution of thin layers of scale is required, contents of 3.5% by weight (calculated as HF) or slightly more are sufficient. However, if thick layers of scale are to be removed or a certain metal removal is intended, the free acid content should be at least 10% by weight HF. If the concentrate according to the invention contains solid, water- and / or acid-soluble oxidizing agent (component d) according to the aforementioned preferred embodiment, a dimensioning which leads to a content of 1 to 10% by weight in the concentrate is particularly advantageous. As a rule, when using weak oxidizing agents, the content is in the upper range, when using strong oxidizing agents in the lower range mentioned above.
Weitere bevorzugte Ausführungsformen der Erfindung bestehen darin, als Komponente d) Permanganat und/oder Peroxid, insbesondere Peroxidisulfat und/oder Carbamidperoxid einzusetzen. Diese Substanzen zeichnen sich durch eine besonders hohe Wirksamkeit aus und haben zudem den Vorteil einer beträchtlichen Beständigkeit - auch im Gemisch mit den anderen Bestandteilen des Konzentrates.Further preferred embodiments of the invention consist of using permanganate and / or peroxide, in particular peroxydisulfate and / or carbamide peroxide, as component d). These substances are characterized by a particularly high effectiveness and also have the advantage of considerable resistance - even when mixed with the other components of the concentrate.
Entsprechend einer anderen vorteilhaften Ausgestaltung der Erfindung sollte das Konzentrat die KomponenteAccording to another advantageous embodiment of the invention, the concentrate should be the component
a) in Form von Alkali- und/oder Ammoniumsalza) in the form of alkali and / or ammonium salt
bl) in Form von Nitrat-, Sulfat- und/oder Zitratsalz,bl) in the form of nitrate, sulfate and / or citrate salt,
b2) in Form von Nitrat- und/oder Zitratsalzb2) in the form of nitrate and / or citrate salt
c) in Form von Zitronensäure, Amidoschwefelsäure und/oder Alkali-/Ammoniu dihydrogenphosphatc) in the form of citric acid, amidosulfuric acid and / or alkali / ammonium dihydrogen phosphate
enthalten. Die einzelnen Komponenten des Konzentrats werden gründlich vermischt. Um eine Entmischung der einzelnen Komponenten - insbesondere beim Transport - zu unterbinden, empfiehlt es sich, diese mit gleicher und zweckmäßigerweise kleiner Teilchengröße einzusetzen.contain. The individual components of the concentrate are mixed thoroughly. In order to prevent segregation of the individual components - especially during transport - it is advisable to use them with the same and expediently small particle size.
Die Lagerfähigkeit des erfindungsgemäßen Konzentrats richtet sich im wesentlichen nach dem Kristallwassergehalt der verwendeten Komponenten. Bei Verwendung weitgehend wasserfreier Komponenten beträgt sie mindestens einen Monat.The shelf life of the concentrate according to the invention depends essentially on the crystal water content of the components used. When using largely water-free components, it is at least one month.
Sofern erforderlich, läßt sich die Lagerfähigkeit noch erheblich steigern, wenn entsprechend einer besonderen Ausführungsform der Erfindung die kristallwasserhaltigen und kristallwasserfreien Komponenten separat gehalten werden, d.h. jeweils nur kristallwasserhaltige und kristallwasserfreie Bestandteile miteinander vermischt werden (sofern mehrere Substanzen der einen oder anderen Art überhaupt zum Einsatz gelangen) . Ein gewisser Nachteil der vorgenannten Getrennthaltung ist allerdings, daß zur Herstellung des Beizmittels zwei Dosierungen vorgenommen werden müssen.If necessary, the shelf life can be increased considerably if, in accordance with a particular embodiment of the invention, the components containing water of crystallization and those free of water of crystallization are kept separate, i.e. only crystal water-containing and crystal water-free components are mixed with each other (if several substances of one type or another are used at all). A certain disadvantage of the aforementioned separation is, however, that two doses have to be carried out to produce the mordant.
Ein Sonderfall der vorliegenden Erfindung mit Getrennthaltung jeweils nur kristallwasserfreier und nur kristallwasserhaltiger Bestandteile der Beizmittel, bei der der kristallwasserhaltige Bestandteil relativ viel Kristallwasser aufweist, besteht darin, eine Beizpaste ohne zusätzliche Verwendung von Wasser anzusetzen. D.h. in diesem Fall bringt eine der beiden Komponenten die zur Ausbildung der Beizpaste erforderliche Wassermenge in chemisch gebundener Form mit. Eine besonders vorteilhafte, anwenderorientierte Ausgestaltung der Erfindung, die auch den vorgenannten Nachteil der Notwendigkeit einer doppelten Dosierung aufhebt, besteht darin, das Konzentrat in Form von Portionspackungeπ zur Herstellung definierter Beizmittelmengen einzusetzen. Je nach Bedarf des Anwenders können die abgepackten Portionen unterschiedlich groß abgestuft sein und beispielsweise zur Herstellung von jeweils 1, 2, 5 oder 10 1 Beizmittel bestimmt sein. Das gilt gleichermaßen für den Fall der Getrennthaltung von kristallwasserhaltigen und kristallwasserfreien Konzentratkomponenten, wobei dann der Inhalt jeweils zweier Packungen in Wasser zu lösen und/oder zu dispergieren ist.A special case of the present invention with separate keeping of only crystal water-free and only crystal water-containing components of the pickling agent, in which the crystal water-containing component has a relatively large amount of crystal water, consists in applying a pickling paste without additional use of water. In this case, one of the two components brings the amount of water required to form the pickling paste in a chemically bound form. A particularly advantageous, user-oriented embodiment of the invention, which also eliminates the aforementioned disadvantage of the need for double dosing, consists in using the concentrate in the form of portion packs for the production of defined amounts of mordant. Depending on the needs of the user, the packaged portions can be graduated to different sizes and can be used, for example, to produce 1, 2, 5 or 10 1 pickling agents. This applies equally to the case of the separation of concentrate components containing water of crystallization and water free of water of crystallization, in which case the contents of two packs in each case must be dissolved and / or dispersed in water.
Auch hierbei ist der vorstehend behandelte Sonderfall der Herstellung einer Beizpaste ohne zusätzliche Verwendung von Wasser möglich. In der Regel wird jedoch das Konzentrat mit Wasser angerührt, wobei sich die Wassermenge insbesondere nach der angestrebten Viskosität des Beizmittels und diese wiederum nach der Form der Applikation, etwa durch Spritzen oder Au streichen, richtet. Die zur Herstellung des Beizmittels erforderliche Wassermenge kann bis zu 60 Gew.-% (bezogen auf das fertige Beizmittel) betragen. Die Herstellung des Beizmittels erfolgt zweckmäßigerweise unter Verwendung eines Rührers bis zur homogenen Verteilung. Je nach der herzustellenden Beizmittelmenge und der Vermischungsintensität des Rührers liegen die erforderlichen Rührzeiten zwischen etwa 1 und 5 Minuten.Here, too, the special case discussed above of producing a pickling paste is possible without the additional use of water. As a rule, however, the concentrate is mixed with water, the amount of water depending in particular on the desired viscosity of the mordant and this in turn on the form of application, for example by spraying or brushing. The amount of water required to produce the mordant can be up to 60% by weight (based on the finished mordant). The pickling agent is expediently produced using a stirrer until homogeneous distribution. Depending on the amount of mordant to be produced and the mixing intensity of the stirrer, the required stirring times are between about 1 and 5 minutes.
Die Erfindung wird anhand der nachfolgenden Beispiele näher erläutert.The invention is illustrated by the following examples.
Beispiel 1example 1
Die Herstellung des Beizmittels erfolgte aus zwei getrennten festen Substanzen I und II. Substanz I bestand aus Ammoniumhydrogenfluorid (NH.HF,) , Substanz II aus einer Mischung von Magnesiumnitrat (Mg(N03)2«6H20) und Kaliumnitrat (KN03) im Gewichtsverhältnis 2 : 1.The pickling agent was produced from two separate solid substances I and II. Substance I consisted of ammonium hydrogen fluoride (NH.HF,), substance II consisted of a mixture of magnesium nitrate (Mg (N0 3 ) 2 «6H 2 0) and potassium nitrate (KN0 3 ) in a weight ratio of 2: 1.
30 Gewichtsteile der Substanz I, 45 Gewichtsteile der Substanz II und 25 Gewichtsteile Wasser wurden unter zweiminütigem kräftigen Rühren vermischt. Nach ca. dreistündigem Stehenlassen hatte das Beizmittel die erwünschte Konsistenz.30 parts by weight of substance I, 45 parts by weight of substance II and 25 parts by weight of water were mixed with vigorous stirring for two minutes. After leaving to stand for about three hours, the mordant had the desired consistency.
Werkstücke aus austenitischem Chromnickelstahl (der Qualität 1.4301), die mit einer WIG-Schweißnaht (Wolfram-Inertgas-Verfahren) versehen waren, wurden mit dem Beizmittel behandelt. Die erzielte Reinigungswirkung entsprach den üblichen Anforderungen. Beispiel 2Workpieces made of austenitic chrome nickel steel (quality 1.4301), which were provided with a TIG weld seam (tungsten inert gas process), were treated with the pickling agent. The cleaning effect achieved corresponded to the usual requirements. Example 2
Die Herstellung des Beizmittels erfolgte wiederum aus zwei getrennten Substanzen I und II. Es waren Substanz I eine Mischung von Ammoniumhydrogenfluorid (NH.HF«) und Ammoniumperoxidisulfat ((NH4)-S_08) im Gewichtsverhältnis 3,5 : 1, Substanz II eine Mischung von Magnesiumnitrat (Mg(N0_)_«6H_0) und Kaliumnitrat (KN0_) im Gewichtsverhältnis 2 : 1.The pickling agent was again produced from two separate substances I and II. Substance I was a mixture of ammonium hydrogen fluoride (NH.HF «) and ammonium peroxydisulfate ((NH 4 ) -S_0 8 ) in a weight ratio of 3.5: 1, substance II one Mixture of magnesium nitrate (Mg (N0 _) _ «6H_0) and potassium nitrate (KN0_) in a weight ratio of 2: 1.
45 Gewichtsteile der Substanz I, 45 Gewichtsteile der Substanz II und 10 Gewichtsteile Wasser wurden, wie in Beispiel 1 angegeben, vermischt und stehen gelassen.45 parts by weight of substance I, 45 parts by weight of substance II and 10 parts by weight of water were mixed as indicated in Example 1 and left to stand.
Mit WIG-Schweißnähten versehene Werkstücke aus Chrom-Nickel-Molybdänstahl (der Qualität 1.4571) wurden mit dem vorstehend angegebenen Beizmittel gereinigt. Das Reinigungsergebnis entsprach den üblichen Anforderungen.Workpieces made of chrome-nickel-molybdenum steel (quality 1.4571) provided with TIG weld seams were cleaned with the above-mentioned pickling agent. The cleaning result met the usual requirements.
Beispiel 3Example 3
Zur Herstellung von 1 kg Beizmittel dienten zwei Portionspackungen. Eine Portionspackung enthieltTwo portion packs were used to produce 1 kg of mordant. One sachet contained
250 g Aluminiumnitrat (A1(N03)3*9H20) 160 g Kalziumnitrat (Ca(N03)2 «4H20) 30 g Kaliumnitrat (KNO_) ,250 g aluminum nitrate (A1 (N0 3 ) 3 * 9H 2 0) 160 g calcium nitrate (Ca (N0 3 ) 2 « 4H 2 0) 30 g potassium nitrate (KNO_),
die anderethe other
170 g Ammoniumhydrogenfluorid (NH HF ) 40 g Ammoniumperoxidisulfat ((NH ) S 0 ) . Der Inhalt der vorgenannten Portionspackungen wurde mit 350 g Wasser vier Minuten unter kräftigem Rühren gründlich vermischt.170 g ammonium hydrogen fluoride (NH HF) 40 g ammonium peroxidisulfate ((NH) S 0). The contents of the aforementioned portion packs were thoroughly mixed with 350 g of water for four minutes with vigorous stirring.
Nach ca. dreistündigem Stehenlassen hatte das Beizmittel die erwünschte Konsistenz. Bei Behandlung der in den Beispielen 1 und 2 näher beschriebenen Werkstücke wurden einwandfrei gereinigte Oberflächen erhalten. After leaving to stand for about three hours, the mordant had the desired consistency. When the workpieces described in Examples 1 and 2 were treated, perfectly cleaned surfaces were obtained.

Claims

PATEN ANSPRUCHE PATEN CLAIMS
1. Festes Konzentrat zur Herstellung eines sauren wässrigen Beizmittels für Metalloberflächen, dadurch gekennzeichnet, daß es als Komponenten jeweils feste, wasser- und/oder säurelösliche1. Solid concentrate for the production of an acidic aqueous mordant for metal surfaces, characterized in that it is solid, water and / or acid-soluble as components
a) Fluorid- und Nitratverbindung,a) fluoride and nitrate compound,
bl) Magnesiumverbindung oderbl) magnesium compound or
b2) Kalzium- und/oder Aluminiumverbindung sowie ggf.b2) calcium and / or aluminum compound and possibly
c) in Wasser sauer reagierende Verbindung enthält.c) contains acidic compound in water.
2. Konzentrat nach Anspruch 1, dadurch gekennzeichnet, daß es zusätzlich als Komponente2. Concentrate according to claim 1, characterized in that it additionally as a component
d) festes, wasser- und/oder säurelösliches Oxidationsmittel enthält.d) contains solid, water- and / or acid-soluble oxidizing agent.
3. Konzentrat nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß es die Komponente bl) enthält.3. Concentrate according to claim 1 or 2, characterized in that it contains component bl).
4. Konzentrat nach Anspruch 1 oder 3, dadurch gekennzeichnet, daß es enthält:4. Concentrate according to claim 1 or 3, characterized in that it contains:
a) Fluoridverbindung in einer Menge von 14 bis 50 Gew.-% (ber. als F) , Nitratverbindung in einer Menge von 10 bis 50 Gew.-% (ber. als NO ) bl) Magnesiumverbindung in einer Menge von l bis 7 Gew.-% (ber. als Mg)a) fluoride compound in an amount of 14 to 50% by weight (calculated as F), nitrate compound in an amount of 10 to 50% by weight (calculated as NO) bl) magnesium compound in an amount of 1 to 7% by weight (calculated as Mg)
b2) Kalzium- und/oder Aluminiumverbindung in einer Menge von jeweils 1,5 bis 5 Gew.-% (ber. als Ca bzw. AI) , wobei bei Einsatz von Ca- und AI-Verbindung die Summe der Anteile 4 bis 9 Gew.-% beträgtb2) calcium and / or aluminum compound in an amount of 1.5 to 5 wt .-% (calc. as Ca or Al), with the use of Ca and Al compound, the sum of the proportions 4 to 9 wt .-%
c) sauer reagierende Verbindungen in einer Menge, daß im mit Wasser angesetzten Beizmittel ein Gehalt an freier Säure entsprechend mindestens 3,5 Gew.-% HF resultiert.c) Acid-reacting compounds in an amount such that a free acid content corresponding to at least 3.5% by weight HF results in the mordant prepared with water.
5. Konzentrat nach Anspruch 2, dadurch gekennzeichnet, daß es die Komponente d) in einer Menge von 1 bis 10 Gew.-% enthält.5. Concentrate according to claim 2, characterized in that it contains component d) in an amount of 1 to 10 wt .-%.
6. Konzentrat nach Anspruch 2 oder 5, dadurch gekennzeichnet, daß es als Komponente d) Permanganat und/oder Peroxid enthält.6. Concentrate according to claim 2 or 5, characterized in that it contains as component d) permanganate and / or peroxide.
7. Konzentrat nach Anspruch 2, 5 oder 6, dadurch gekennzeichnet, daß es als Komponente d) Peroxidisulfat und/oder Carbamidperoxid enthält. 7. Concentrate according to claim 2, 5 or 6, characterized in that it contains as component d) peroxydisulfate and / or carbamide peroxide.
8. Konzentrat nach Anspruch lr 3 oder 4, dadurch gekennzeichnet, daß es die Komponente8. concentrate according to claim l r 3 or 4, characterized in that it is the component
a) in Form von Alkali- und/oder Ammoniumsalza) in the form of alkali and / or ammonium salt
bl) in Form von Nitrat-, Sulfat- und/oder Zitratsalz,bl) in the form of nitrate, sulfate and / or citrate salt,
b2) in Form von Nitrat- und/oder Zitratsalzb2) in the form of nitrate and / or citrate salt
c) in Form von Zitronensäure, Amidoschwefelsäure und/oder Alkali-/Ammoniumdihydrogenphosphatc) in the form of citric acid, amidosulfuric acid and / or alkali / ammonium dihydrogen phosphate
enthält.contains.
9. Konzentrat nach einem oder mehreren der Ansprüche 1 bis 8, dadurch gekennzeichnet, daß kristallwasserhaltige und kristallwasserfreie Komponenten jeweils separat gehalten sind.9. Concentrate according to one or more of claims 1 to 8, characterized in that water-containing and water-free components are each kept separately.
10. Anwendung des Konzentrats nach einem oder mehreren der Ansprüche 1 bis 9 in Form von Portionspackungen zur Herstellung einer definierten Beizmittelmenge. 10. Use of the concentrate according to one or more of claims 1 to 9 in the form of portion packs for producing a defined amount of mordant.
PCT/EP1993/000906 1992-04-17 1993-04-15 Concentrate for the preparation of metal mordants WO1993021362A2 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
EP93908942A EP0589028B1 (en) 1992-04-17 1993-04-15 Concentrate for the preparation of metal mordants
DE59301633T DE59301633D1 (en) 1992-04-17 1993-04-15 CONCENTRATE FOR THE PRODUCTION OF METAL MAKING AGENTS

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE4212891A DE4212891A1 (en) 1992-04-17 1992-04-17 Concentrate for the manufacture of metal mordants
DEP4212891.9 1992-04-17

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WO1993021362A2 true WO1993021362A2 (en) 1993-10-28
WO1993021362A3 WO1993021362A3 (en) 1994-03-03

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Publication number Priority date Publication date Assignee Title
WO1997041278A1 (en) * 1996-04-29 1997-11-06 Ki Won Lee A method for pickling metallic surface, pickling solutions therefor, and process for regenerating spent pickling solutions

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Publication number Priority date Publication date Assignee Title
AUPP762398A0 (en) * 1998-12-09 1999-01-14 Cairnscorp Technology Pty. Limited Cleaning solutions containing citric acid and uses thereof

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JPS5794578A (en) * 1980-12-04 1982-06-12 Taimu Chem:Kk Acidic cleaner having viscosity
EP0058257A1 (en) * 1981-02-14 1982-08-25 Metallgesellschaft Ag Pickling and descaling paste for metals
DE3530132A1 (en) * 1985-08-23 1987-02-26 August Wittig Surface pickling and derusting paste for cleaning metal surfaces, especially made of alloy steel and/or aluminium and aluminium alloys
DD248379A1 (en) * 1986-04-22 1987-08-05 Bitterfeld Chemie MEANS FOR THE ACIDING OF AUSTENIC STAINLESS STEEL SURFACES

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Publication number Priority date Publication date Assignee Title
JPS5794578A (en) * 1980-12-04 1982-06-12 Taimu Chem:Kk Acidic cleaner having viscosity
EP0058257A1 (en) * 1981-02-14 1982-08-25 Metallgesellschaft Ag Pickling and descaling paste for metals
DE3530132A1 (en) * 1985-08-23 1987-02-26 August Wittig Surface pickling and derusting paste for cleaning metal surfaces, especially made of alloy steel and/or aluminium and aluminium alloys
DD248379A1 (en) * 1986-04-22 1987-08-05 Bitterfeld Chemie MEANS FOR THE ACIDING OF AUSTENIC STAINLESS STEEL SURFACES

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Title
CHEMICAL ABSTRACTS, vol. 108, no. 16, 18. April 1988, Columbus, Ohio, US; abstract no. 135900n, WIEDNER WOLGANG ET AL. 'acid pastes for pickling austenitic stainless steels.' Seite 260 ;Spalte 2 ; & DD,A,248 379 (VEB CHEMIEKOMBINAT BITTERFELD) 5. August 1987 *
PATENT ABSTRACTS OF JAPAN vol. 6, no. 180 (C-125)(1058) 14. September 1982 & JP,A,57 094 578 (TAIMU CHEMICAL K.K.) 12. Juni 1982 *
See also references of EP0589028A1 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1997041278A1 (en) * 1996-04-29 1997-11-06 Ki Won Lee A method for pickling metallic surface, pickling solutions therefor, and process for regenerating spent pickling solutions
US6361613B2 (en) * 1996-04-29 2002-03-26 Ki Won Lee Method for pickling mettalic surface, pickling solutions therefor, and process for regenerating spent pickling solutions

Also Published As

Publication number Publication date
DE59301633D1 (en) 1996-03-28
EP0589028B1 (en) 1996-02-14
DE4212891A1 (en) 1993-10-21
AU3953293A (en) 1993-11-18
EP0589028A1 (en) 1994-03-30
WO1993021362A3 (en) 1994-03-03

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