JP2013001963A - Corrosion inhibitor composition for acid cleaning - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a corrosion inhibitor composition for acid cleaning, which shows an extremely high corrosion inhibition effect to other metals as well as iron and steel even under a severe acid-cleaning condition due to high-concentration acid or the like, a metal corrosion inhibitory acid cleaning liquid including the composition, and a cleaning method of metal using the acid cleaning liquid.SOLUTION: The metal corrosion inhibitor composition contains rosinamine and at least one of inorganic phosphate and organic phosphonate.

Description

  The present invention is a composition for suppressing corrosion of a metal itself by adding to an acid cleaning liquid for removing an oxide film such as rust and scale on a metal surface, an acid cleaning liquid containing the metal corrosion inhibitor composition, And a method for cleaning a metal using the acid cleaning liquid.

  Conventionally, inorganic acids, organic acids, and the like have been used to remove oxide films such as rust and scale attached to the metal surface. These acids dissolve the metal oxide and expose the metal substrate.

  However, if only acid is used to remove rust and the like, not only rust but also metal substrates are affected by corrosion, hydrogen embrittlement, and pitting corrosion. Therefore, various corrosion inhibitors such as amine compounds, sulfur compounds and acetylene alcohols are used in combination for the purpose of suppressing or preventing such harmful effects.

  Among such acid cleaning corrosion inhibitors, for example, those described in Patent Documents 1 and 2 are known as amine compounds. In addition, rosinamine D manufactured by Hercules is commercially available as a corrosion inhibitor used for acid cleaning of steel.

JP 2000-96272 A JP 2003-166089 A

  As described above, various compounds such as amine compounds have been developed as corrosion inhibitors used when washing metals with acids.

  However, although the corrosion inhibitor containing an amine compound is effective for acid cleaning of steel, the corrosion inhibitory effect on zinc, zinc alloy, aluminum alloy and the like is not high. In addition, quaternary ammonium salts, which are surfactants that are generally blended into steel corrosion inhibitors, are not sufficiently effective in inhibiting corrosion of zinc, aluminum, and alloys thereof.

  On the other hand, if corrosion can be suppressed regardless of the type of metal, there is no need to change the composition of the corrosion inhibitor according to the metal to be cleaned, and the cleaning efficiency is further increased. The product value of the acid cleaning solution is extremely high.

  Accordingly, an object of the present invention is to provide a corrosion inhibitor for acid cleaning that exhibits an extremely high corrosion inhibitory effect not only on steel, but also on other metals, even under severe pickling conditions such as high-concentration acid. An object of the present invention is to provide a composition, a metal corrosion-inhibiting acid cleaning liquid containing the composition, and a metal cleaning method using the acid cleaning liquid.

  The inventors of the present invention have made extensive studies to solve the above problems. As a result, it was found that a high corrosion inhibitory effect on metals in general can be obtained by using a salt thereof instead of phosphoric acid or phosphonic acid itself in addition to rosinamine, thereby completing the present invention.

  The metal corrosion inhibitor composition according to the present invention is characterized by containing rosinamine and at least one of an inorganic phosphate or an organic phosphonate.

  Examples of the rosin amine include at least one selected from dehydroabiethylamine, dihydroabiethylamine, tetrahydroabiethylamine, and these alkylene oxide adducts. Examples of the organic phosphonate include 1-hydroxyethylidene-1,1-diphosphonic acid, aminotrimethylenephosphonic acid, 2-phosphonobutane-1,2,4-tricarboxylic acid, ethylenediaminetetra (methylenephosphonic acid), diethylenetriaminepenta Mention may be made of at least one salt selected from (methylenephosphonic acid).

  The metal corrosion inhibitor composition according to the present invention preferably further contains a nonionic surfactant and / or an amine compound having a polyalkylene oxide moiety in the molecule. In some cases, rosinamine is difficult to dissolve in an acid solution. By adding these, the solubility of rosinamine in an acid solution is improved.

  The metal corrosion inhibitor composition according to the present invention is used in at least one aqueous solution selected from hydrochloric acid, sulfuric acid, phosphoric acid, and sulfamic acid, and thereby oxides such as rust and scale on the metal surface. While removing, the metal itself can be protected and its corrosion can be suppressed.

  The effect of the metal corrosion inhibitor composition according to the present invention is particularly effective for aluminum, zinc, and alloys containing at least one of these metals. Conventionally, a corrosion inhibitor composition in acid cleaning of steel has been well studied, but the corrosion inhibitory effect of the conventional corrosion inhibitor composition on the above metals has not been sufficient. On the other hand, the metal corrosion inhibitor composition according to the present invention can exhibit an excellent corrosion inhibitory effect on these metals.

  The metal corrosion-inhibiting acid cleaning liquid according to the present invention contains the above-described metal corrosion inhibitor.

  The method for cleaning a metal according to the present invention includes a step of spraying the metal corrosion-inhibiting acid cleaning solution onto a metal surface or immersing a metal in the metal corrosion-inhibiting acid cleaning solution.

  If the corrosion inhibitor composition according to the present invention is added to an acid solution to wash the metal, it becomes possible to remove oxides such as rust and scale while suppressing corrosion of the metal itself. In particular, there are conventional corrosion inhibitors that can be used for acid cleaning of steel, but copper, aluminum, magnesium alloys that are easily corroded in acidic solutions, zinc, aluminum alloys rich in copper, zinc and aluminum There was nothing that could effectively suppress the corrosion of zinc alloys such as brass including this during acid cleaning. On the other hand, the corrosion inhibitor composition according to the present invention can effectively suppress corrosion of the above aluminum alloy as well as steel.

  Therefore, the present invention is extremely industrially useful as it is not necessary to adjust the components according to the target metal for acid cleaning, and can effectively and effectively inhibit corrosion in acid cleaning of various metals.

  The metal corrosion inhibitor composition according to the present invention is characterized by containing rosinamine and at least one of an inorganic phosphate or an organic phosphonate.

  Rosin amine is an amine compound contained in a residual resin (rosin) obtained by removing volatile components from resin oil obtained from a pine family plant, and is an amine derivative of abietic acid which is a main component of rosin. Specific examples include at least one selected from the following dehydroabiethylamine, dihydroabiethylamine, tetrahydroabiethylamine, and these alkylene oxide adducts.

  The alkylene oxide adduct is a compound in which ethylene oxide, propylene oxide, 1,2-butylene oxide, isobutylene oxide or 2,3-butylene oxide is added to the amino group of the amine.

  In the present invention, rosinamine may be used alone or in combination of two or more.

  For metals such as steel, copper, and aluminum, rosinamine alone can provide a corrosion-inhibiting effect, but in particular, corrosion in an acid solution for aluminum alloys containing a large amount of magnesium, zinc, copper, and alloys containing zinc. The inhibitory effect is not sufficient. Therefore, in the present invention, an inorganic phosphate or an organic phosphonate is added to rosinamine to remarkably improve the corrosion inhibition effect on these metals.

The inorganic phosphate added to the corrosion inhibitor composition according to the present invention is an inorganic phosphoric acid salt represented by the formula: HP (═O) (OH) ₂ . The organic phosphate is a salt of an organic phosphoric acid represented by the formula: RP (═O) (OH) ₂ (wherein R represents an organic group not specified).

  The organic phosphate is not particularly limited, and examples thereof include 1-hydroxyethylidene-1,1-diphosphonic acid, aminotrimethylenephosphonic acid, 2-phosphonobutane-1,2,4-tricarboxylic acid, ethylenediaminetetra (methylenephosphone). Acid) and at least one salt selected from diethylenetriaminepenta (methylenephosphonic acid).

The salt of inorganic phosphoric acid or organic phosphonic acid is not particularly limited, and examples thereof include alkali metal salts, ammonium salts, and amine salts. Examples of the alkali metal ions constituting the alkali metal salt include lithium ions, sodium ions, and potassium ions. In addition, the amine constituting the amine salt is not particularly limited. For example, alkanolamines such as monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine; dimethylethanolamine, diethylethanol Monoalkyl represented by amine, alkanolalkylamine such as 2-amino-2-methyl-propanolamine; chemical formula: R ¹ NH ₂ (wherein R ¹ represents a hydrocarbon group having 8 to 20 carbon atoms) Examples include primary amines; alkyldiaminopropane represented by the chemical formula: R ² NH (CH ₂ ) ₃ NH ₂ (wherein R ² represents a hydrocarbon group having 5 to 17 carbon atoms).

  Any one of inorganic phosphate and organic phosphate may be used alone, or both may be used in combination, or two or more of them may be used in combination.

  The ratio of rosinamine and inorganic phosphate or organic phosphonate in the corrosion inhibitor composition according to the present invention is not particularly limited and may be appropriately adjusted. For example, the ratio of inorganic phosphate and organic phosphonate to rosinamine The total amount can be 1 part by mass or more and 10 parts by mass or less. As the said ratio, 3 mass parts or more are preferable, 4 mass parts or more are more preferable, 8 mass parts or less are preferable, 7 mass parts or less are more preferable, and 5 mass parts or less are more preferable.

  Addition of rosinamine to an acid solution may cause instability such as turbidity and insoluble matter over time. Therefore, the metal corrosion inhibitor composition is preferably a nonionic surfactant and / or a polyalkylene oxide in the molecule. It is preferable to add an amine compound having a moiety. By adding these components, the solubility of rosinamine is improved in the acid solution. Moreover, it is thought that it has the effect | action which improves the permeability to the metal surface of a composition. Furthermore, they themselves may exhibit a metal corrosion inhibiting effect.

Examples of the alkylene oxide that the amine compound has include C _2-4 alkylene oxide such as ethylene oxide, propylene oxide, 1,2-butylene oxide, isobutylene oxide, and 2,3-butylene oxide.

  Examples of the amine compound include an amine polyalkylene oxide adduct represented by Chemical Formula 1;

(Wherein R ¹ represents a saturated hydrocarbon group having 8 to 20 carbon atoms, an unsaturated hydrocarbon group having 8 to 20 carbon atoms, or an alkanoyl group having 8 to 20 carbon atoms; R ^{3 to} R ⁶ each independently represents a hydrogen atom, a methyl group or an ethyl group; x1 and y1 each independently represents an integer of 1 or more and 10 or less)
And a diamine polyalkylene oxide adduct represented by Chemical Formula 2 and the like.

（式中、Ｒ²は、炭素数５以上、３０以下の飽和炭化水素基、炭素数５以上、３０以下の不飽和炭化水素基、炭素数５以上、３０以下のアルカノイル基、または−（ＣＲ⁷Ｒ⁸ＣＲ⁹Ｒ¹⁰Ｏ）_ｚ2Ｈ基を示し；Ｒ⁷〜Ｒ¹⁰はそれぞれ独立して水素原子、メチル基またはエチル基を示し；ｘ２、ｙ２およびｚ２はそれぞれ独立して１以上、１０以下の整数を示し；ｗ２は１以上、６以下の整数を示す）

(In the formula, R ² is a saturated hydrocarbon group having 5 to 30 carbon atoms, an unsaturated hydrocarbon group having 5 to 30 carbon atoms, an alkanoyl group having 5 to 30 carbon atoms, or — (CR ⁷ R ⁸ CR ⁹ R ¹⁰ O) _z2 H group; R ^{7 to} R ¹⁰ each independently represents a hydrogen atom, a methyl group or an ethyl group; x2, y2 and z2 each independently represent 1 or more, 10 The following integer is shown; w2 is an integer of 1 or more and 6 or less)

  Examples of the nonionic surfactant include polyoxyethylene alkyl ether obtained by addition polymerization of ethylene oxide to rosin ethoxylate or higher alcohol. Specific examples thereof include, but are not limited to, polyoxyethylene oleyl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, polyoxyethylene lauryl ether, and the like. As the nonionic surfactant, polyoxyethylene alkylphenyl ether, fatty acid diethanolamide, fatty acid sorbitan ester, fatty acid polyoxyethylene sorbitan ester, and the like can be used.

  Any one of the nonionic surfactant and the amine compound may be used, or both may be used in combination, or two or more of them may be used in combination. In particular, the amine compound may be a mixture of two or more.

  The proportions of the nonionic surfactant and the amine compound in the corrosion inhibitor composition according to the present invention are not particularly limited and may be appropriately adjusted. For example, 0.1 parts by mass or more and 10 parts by mass with respect to rosinamine It can be as follows. As the said ratio, 0.5 mass part or more is preferable, 1 mass part or more is more preferable, 5 mass parts or less are preferable, 4 mass parts or less are more preferable, and 2 mass parts or less are more preferable.

  Components other than those described above may be added to the metal corrosion inhibitor composition according to the present invention. For example, a solvent, a surfactant other than the above, a metal corrosion inhibitor other than the above, and the like can be blended.

  As the solvent, in addition to water, for example, a water-miscible organic solvent may be used in order to improve the solubility of rosinamine. Examples of the water-miscible organic solvent include alcohol solvents such as methanol and ethanol; ether solvents such as tetrahydrofuran and diethylene glycol monobutyl ether; amide solvents such as dimethylformamide and dimethylacetamide; dimethyl sulfoxide and the like.

  Although the metal corrosion inhibitor other than the above is not particularly limited, for example, it may be used in combination with other corrosion inhibitors. Other corrosion inhibitors used in combination include, for example, heterocyclic nitrogen compounds such as benzotriazole, tolyltriazole, and imidazoles; quaternary that is used as a fabric softener and shampulence agent and has relatively good human safety. Cation agent; alkylamine, polyamine, polyethyleneimine, polyallylamine, ethylenediamine ethylene oxide / propylene oxide adduct (Pluronic TR series manufactured by Asahi Denka Co., Ltd.), cinnamic aldehyde, hydantoin, 5,5-dimethylhydantoin, allantoin, glyoxylic acid And reducing agents such as phosphorous acid, hypophosphorous acid, diethylhydroxyamine, L-sorbic acid, and L-ascorbic acid.

  The proportion of the other corrosion inhibitor is not particularly limited and may be adjusted as appropriate. For example, it can be 0.1 parts by mass or more and 10 parts by mass or less with respect to rosinamine. As the said ratio, 0.2 mass part or more is preferable, 0.5 mass part or more is more preferable, 5 mass parts or less are preferable, 3 mass parts or less are more preferable, and 2 mass parts or less are more preferable.

  The method for producing the metal corrosion inhibitor composition according to the present invention is not particularly limited, and the above components may be simply mixed, or the above components may be dissolved in a solvent capable of dissolving and used as a high concentration solution. Sometimes it may be diluted moderately. The order of mixing and dissolution is not particularly limited, and all the above components may be added to the solvent, or may be added in order or in small portions. Heating may be used to promote dissolution.

  The metal corrosion inhibitor composition according to the present invention can suppress the corrosion of the metal itself by adding it to the acid solution for washing the metal.

  The content ratio of the metal corrosion inhibitor composition in the acid solution for metal cleaning may be adjusted as appropriate. For example, rosinamine is 0.001% by mass or more and 10% by mass or less based on the total amount of the cleaning agent containing acid. It can mix | blend as follows. If the said ratio is 0.001 mass% or more, the metal corrosion inhibitory effect will be more reliably exhibited. On the other hand, if the proportion exceeds 10% by mass, the effect of inhibiting the corrosion of the metal is saturated and a problem of cost arises. As the said ratio, 0.01 mass% or more is more preferable, and 1 mass% or less is more preferable.

  The acid to be added to the acid cleaning agent to be cleaned is not particularly limited as long as it can dissolve the surface oxide of the metal to be cleaned. For example, inorganic acids such as hydrochloric acid, sulfuric acid, phosphoric acid, sulfamic acid, etc. Mention may be made of acids. In addition to these inorganic acids, organic acids such as oxalic acid, succinic acid, glutaric acid, adipic acid, phthalic acid, maleic acid, citric acid, malic acid and tartaric acid may be used in combination. The concentration of the acid added to the acid cleaning liquid according to the present invention may be adjusted as appropriate, and may be, for example, about 5% by mass to 30% by mass.

  The metal corrosion-inhibiting acid cleaning liquid according to the present invention can be used in the same manner as a normal metal cleaning liquid. For example, the metal corrosion-inhibiting acid cleaning agent of the present invention may be sprayed on the surface of the metal to be cleaned, or the metal to be cleaned may be immersed in the metal corrosion-inhibiting acid cleaning agent of the present invention.

  Usually, when a metal is washed with a strong acid, the metal itself is also corroded. In the case where the metal to be cleaned is steel, cleaning agents for cleaning while suppressing such corrosion have been well studied, but aluminum alloys, zinc containing a lot of magnesium and zinc that are particularly susceptible to acid corrosion, zinc, No cleaning agent has been developed that exhibits a sufficient corrosion-inhibiting effect on zinc alloys and the like. On the other hand, the metal corrosion inhibitor composition according to the present invention exhibits an excellent corrosion inhibitory effect on the above alloys and the like. Therefore, according to the acid cleaning agent containing this, the efficiency of the entire metal is suppressed while suppressing corrosion. Can be cleaned automatically.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited by the following examples, but may be appropriately modified within a range that can meet the purpose described above and below. Of course, it is possible to implement them, and they are all included in the technical scope of the present invention.

Production Example 1 Production of Acid Corrosion Inhibitor Composition for Acid Washing Each component was dissolved in ion-exchanged water at the blending ratio (% by mass) shown in Table 1, and for acid washing in Examples 1 to 5 and Comparative Examples 1 to 8 A metal corrosion inhibitor composition was prepared. As rosinamine, C-RAM manufactured by Rika Finetech Co., Ltd. was used, and as polyoxyalkylene alkyl ether, NAROACTY CL-95 manufactured by Sanyo Chemical Industries, Ltd. was used.

Production Example 2 Production of Metal Corrosion Inhibiting Acid Cleaning Liquid Inhibiting metal corrosion by adding the metal corrosion inhibitor composition for acid washing of Examples 1 to 5 and Comparative Examples 1 to 8 to 10% hydrochloric acid at a ratio of 2% by mass 150 mL of acidic acid cleaning solution was prepared.

Test example 1
Each obtained washing | cleaning liquid was put into a 200 mL capacity | capacitance glass bottle, and temperature was adjusted to 20 degreeC.

Separately, as a metal test piece, JIS G 3141 SPCC steel plate polished and degreased with # 240 emery paper, JIS G 3101 SS-400 steel plate, copper plate JIS H 3100 C1100P polished and degreased with water resistant emery paper # 320, zinc A plate, an aluminum plate JIS H 4000 A1050P, JIS H 4000 A5052P (Mg: 2.2 to 2.8%), and JIS H 4000 A5083P (Mg: 4.0 to 4.9%) were prepared. The dimension of the metal test piece was 60 × 40 × 1.0 mm (surface area: 50 cm ² ), and the mass was measured in advance.

  Each of these metal test pieces was immersed in each cleaning solution for 30 minutes. Subsequently, after thoroughly washing with ion exchange water and drying, the mass was measured. The mass difference between the metal test pieces before and after the immersion treatment was determined, and the amount of corrosion relative to the surface area was calculated. The results are shown in Table 2.

  As shown in the above results, when the cleaning agent of Comparative Example 1 containing no corrosion inhibitor was used, corrosion occurred on all metals, and the degree of corrosion was particularly large with zinc or aluminum.

  Comparative Examples 2-3 are examples of cleaning liquids containing only rosinamine as a corrosion inhibitor. Such a cleaning solution showed a high corrosion inhibiting effect not only on SPCC steel plates and SS-400 steel plates but also on copper and pure aluminum. However, the corrosion inhibitory effect on the aluminum alloy (A5083P) and zinc plate containing a large amount of magnesium was not sufficient.

  Comparative Example 4 is an example in which aminotrimethylenephosphonic acid used in Examples 1 to 3 was used without neutralization in addition to rosin amine, and Comparative Example 5 was used in Examples 3 to 4 in addition to rosin amine. This is an example in which an octylamine salt of citric acid is used instead of an octylamine salt of organic phosphonic acid. These also had a poor corrosion inhibiting effect on zinc plates and aluminum alloys.

  Comparative Examples 6 to 8 are quaternary ammonium salt benzalkonium chloride, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, and Β-alanine type amphoteric surface activity that are generally used as iron-based corrosion inhibitors. This is an example in which an agent is added. Although these also showed the corrosion inhibitory effect with respect to a steel plate and copper, the corrosion inhibitory effect with respect to another metal was low.

  In contrast to the above comparative example, when Examples 1 to 5 according to the present invention containing an organic phosphonate together with rosinamine were used, not only steel, but also zinc, aluminum, and magnesium that are easily corroded by acid. It was proved to show an excellent corrosion inhibitory effect on the aluminum alloy contained. As another corrosion inhibitor component to be used in combination with rosinamine, sodium salt of aminotrimethylene phosphonic acid (ATMP) was used in Example 1, triethanolamine salt of ATMP in Example 2, and octylamine salt of ATMP in Example 3. In Example 4, an octylamine salt of 1-hydroxyethylidene 1,1-diphosphonic acid (HEDP) was added, and in Example 5, an octylamine salt of phosphoric acid was added.

Claims (9)

  A metal corrosion inhibitor composition comprising rosinamine and at least one of an inorganic phosphate or an organic phosphonate.   The metal corrosion inhibitor composition according to claim 1, wherein the rosin amine is at least one selected from dehydroabiethylamine, dihydroabiethylamine, tetrahydroabiethylamine, and alkylene oxide adducts thereof.   The organic phosphonate is 1-hydroxyethylidene-1,1-diphosphonic acid, aminotrimethylenephosphonic acid, 2-phosphonobutane-1,2,4-tricarboxylic acid, ethylenediaminetetra (methylenephosphonic acid), diethylenetriaminepenta (methylenephosphon). The metal corrosion inhibitor composition according to claim 1 or 2, which is at least one salt selected from an acid.   Furthermore, a nonionic surfactant is contained, The metal-corrosion inhibitor composition in any one of Claims 1-3 characterized by the above-mentioned.   Furthermore, the metal corrosion inhibitor composition in any one of Claims 1-4 containing the amine compound which has a polyalkylene oxide part in a molecule | numerator.   The metal corrosion inhibitor composition according to any one of claims 1 to 5, which is used in at least one aqueous solution selected from hydrochloric acid, sulfuric acid, phosphoric acid and sulfamic acid.   The metal corrosion inhibitor composition according to any one of claims 1 to 6, wherein the target metal is aluminum, zinc, or an alloy containing at least one of these metals.   A metal corrosion-inhibiting acid cleaning solution comprising the metal corrosion inhibitor composition according to any one of claims 1 to 7 and an acid.   A method for cleaning a metal, comprising a step of spraying the metal corrosion-inhibiting acid cleaning liquid according to claim 8 on a metal surface or immersing the metal in the metal corrosion-inhibiting acid cleaning liquid according to claim 8.