CN100462007C - A kind of anti-corrosion bactericide and preparation method thereof - Google Patents

Abstract

The invention discloses a novel corrosion inhibition bactericide, which is a derivative of benzotriazole, belongs to a cationic compound, and is mainly characterized in that: firstly, the intermediate reaction product N-alkyl benzotriazole is obtained through the reaction of benzotriazole and alkyl halide, and then the product is obtained through the reaction of the N-alkyl benzotriazole and quaternary alkylating agent. The product can greatly reduce the surface tension of the solution, has good corrosion inhibition effect on copper and carbon steel, and has good sterilization effect.

Description

A kind of anti-corrosion bactericide and preparation method thereof

technical field

The invention relates to a corrosion-inhibiting bactericide and a preparation method thereof, in particular to a corrosion-inhibiting bactericide with benzotriazole as a parent derivative and a preparation method thereof.

Background technique

Since the 1950s, benzotriazole (BTA) has been widely used in industry as a special corrosion inhibitor for copper and its alloys. Studies have shown that: benzotriazole mainly forms a dense Cu-BTA protective film on the surface of copper and its alloys, which can effectively inhibit the corrosion of copper by the medium. In neutral and weak alkaline medium, benzotriazole exhibits excellent corrosion inhibition effect. However, in acidic solution, the corrosion inhibition effect of BTA is not as good as that in neutral and weak alkaline. Accordingly, in order to improve the corrosion inhibition effect of BTA on various metals and various media (acids, alkalis, salts), the application and development of BTA and its derivatives has been receiving attention. For example, derivatives of benzotriazole such as tolylbenzotriazole, carboxybenzotriazole, carboxybenzotriazolidinyl ester, etc. have been researched and developed.

As we all know, cationic surfactants have strong bactericidal and bacteriostatic properties. For example, pyridinium salts and imidazoline salts not only have broad-spectrum bactericidal and bacteriostatic properties, but also have the advantages of being odorless, highly water-soluble, and less irritating.

Contents of the invention

The object of the present invention is to provide an additive with corrosion inhibition and bactericidal effect, and the corrosion inhibitor and bactericide belongs to alkyl benzotriazole cationic compounds. Another object of the present invention is to provide a method for preparing a corrosion-inhibiting bactericide, which is simple in operation, mild in reaction conditions, and easy to control.

The technical scheme of the present invention is: based on the corrosion inhibition effect of the benzotriazole parent and the bactericidal effect of the cationic surfactant, we propose an additive with both corrosion inhibition and bactericidal properties - alkyl benzotriazole The cationic derivative also provides a preparation method of the corrosion inhibitor and bactericide.

The specific technical scheme of the present invention is: a compound with corrosion inhibition and bactericidal effect, its structural formula is:

Wherein R ₁ is C _n H _2n+1 (n: 4～18) or C ₆ H ₅ CH ₂ ; R ₂ is CH ₃ , CH ₃ CH ₂ , CH ₂ CH ₂ OH, CH ₂ COOH, C ₆ H ₅ CH ₂ or

X ₂ is (CH ₃ )SO ₄ , (CH ₃ CH ₂ )SO ₄ , Cl or Br.

The present invention also provides the preparation method of above-mentioned corrosion-inhibiting bactericide, its steps are:

A. Alkylation reaction: benzotriazole is added into a solvent to make a solution, which is added to the reaction vessel, then a catalyst with a molar ratio of 1.0 to 1.5 based on benzotriazole is added, stirred, and dissolved; Take triazole as the basis of 0.8-1.2 molar ratio of alkylating reagent, stir, heat and reflux for reaction, evaporate the solvent, add water to wash, separate liquid, and dry to obtain the intermediate product N-alkylbenzotriazole;

B. Quaternization reaction: Take the above-mentioned intermediate product N-alkylbenzotriazole, dissolve it with a solvent, add it to the reaction vessel, and add 1-3 based on the intermediate product N-alkylbenzotriazole The molar ratio of the quaternizing agent is stirred and heated to react, and the solvent is distilled to obtain the product.

Wherein the heating reflux reaction temperature in step A is 60-80°C, and the reaction time is 20-24 hours; the reaction temperature in step B is 50-80°C; reaction time: 2-3h.

The solvent is water or ethanol; the catalyst is NaOH, KOH, CH ₃ CH ₂ ONa; the alkylating agent is C _n H _2n+1 X or C ₆ H ₅ CH ₂ X, where n : 4-18, X is Cl, Br or I; Described quaternization reagent is: dimethyl sulfate, diethyl sulfate, chloroethanol, epichlorohydrin, benzyl chloride, chloroacetic acid or bromoethane .

The two-step reaction equation is:

1. Alkylation reaction:

2. Quaternization reaction:

Wherein M is Na or K; R ₁ is C _n H _2n+1 (n: 4～18) or C ₆ H ₅ CH ₂ ; X ₁ is Cl, Br or I;

X₂为(CH₃)SO₄、(CH₃CH₂)SO₄、Cl或Br。R ₂ is CH ₃ , CH ₃ CH ₂ , CH ₂ CH ₂ OH, CH ₂ COOH, C ₆ H ₅ CH ₂ or

X ₂ is (CH ₃ )SO ₄ , (CH ₃ CH ₂ )SO ₄ , Cl or Br.

Beneficial effect:

1. The corrosion-inhibiting bactericide of the present invention is a yellow or brown-yellow transparent liquid, has good water solubility, and has the effect of reducing the surface tension of water.

2. The product provided by the present invention has both corrosion inhibition and bactericidal properties. The corrosion inhibition and bactericide of the corrosion inhibitor is similar to that of BTA on copper. It mainly forms a dense protective film on the copper surface through the triazole heterocycle and copper. Moreover, the introduction of alkyl chains increases the compactness of the protective film and improves the corrosion inhibition effect. It belongs to a mixed type corrosion inhibitor, and has a good inhibitory effect on anode dissolution and cathode hydrogen evolution; the corrosion inhibitor and bactericide of the invention has the structure of a cationic surfactant at the same time, and has an excellent bactericidal effect. And under acidic conditions, the corrosion inhibition effect on copper is better than that of benzotriazole; it has an efficient corrosion inhibition effect on carbon steel in pickling solution (98.4%). Compared with the amount of benzimidazole pickling agent, it is much reduce.

4. The preparation method provided by the invention has simple operation, mild reaction conditions and easy control.

Description of drawings

Fig. 1 is a ¹ H NMR spectrum of a dodecylbenzotriazole cationic compound.

Specific implementation method

Example 1:

Take 28.56 g (0.24 mol) of benzotriazole and dissolve it with 100 ml of distilled water. Add 12 g of NaOH (0.3 mol), stir and heat. Dissolve NaOH completely, add 22.16g (0.24mol) of n-chlorobutane, increase stirring, keep the reaction temperature at 60-80°C, react for 20 hours, distill the solvent, wash the excess benzotriazole with heated water, separate It is the water layer and the oil layer, and the water layer is separated to obtain the oil layer, and then dried with calcium chloride to obtain 20.9 g of the intermediate product N-n-butylbenzotriazole.

Take 10.79g (0.06mol) of the intermediate product N-n-butyl benzotriazole, use 70ml of distilled water as a solvent, add it to a four-necked flask, control the temperature at 50°C, and add 22.68g (0.18mol) of dimethyl sulfate , stirred and reacted for 3 hours to obtain 33.2 g of n-butyl benzotriazole cationic compound.

Example 2:

Take 28.56 g (0.24 mol) of benzotriazole and dissolve it with 100 ml of distilled water. Add 16.8 g of KOH (0.3 mol), stir and heat. KOH is completely dissolved, add 29.7g (0.20mol) of chloro-n-octane, increase stirring, and keep the reaction temperature at 60-80°C. After reacting for 20 hours, distill the solvent, wash the excess benzotriazole with heated water, and separate It is the water layer and the oil layer, and the water layer is separated to obtain the oil layer, and then dried with calcium chloride to obtain 37.6 g of the intermediate product N-n-octylbenzotriazole.

Take 13.86g (0.06mol) of the intermediate product N-octylbenzotriazole, use 70ml of absolute ethanol as a solvent, add it to a four-necked flask, control the temperature at 50°C, and add 16.65g (0.18mol) of epichlorohydrin mol), stirred and reacted for 3 hours to obtain 28.4 g of n-octylbenzotriazole cationic compound.

Example 3:

Take 28.56 g (0.24 mol) of benzotriazole and dissolve it with 100 ml of distilled water. Add 20.4 g of CH ₃ CH ₂ ONa (0.3 mol), stir and heat. CH ₃ CH ₂ ONa is completely dissolved, add 53.2g (0.26mol) of dodecane chloride, increase stirring, keep the reaction temperature at 60-80°C, after 24 hours of reaction, distill the solvent, and wash the excess benzotri Azole is divided into a water layer and an oil layer, and the water layer is separated to obtain an oil layer, and then dried with calcium chloride to obtain 52.45 g of the intermediate product N-dodecylbenzotriazole.

Take 17.60 g (0.06 mol) of the intermediate product N-dodecylbenzotriazole, use 70 ml of distilled water as a solvent, add it to a four-neck flask, control the temperature at 50 ° C, add 11.39 g (0.09 mol) of benzyl chloride, The reaction was stirred for 3 hours to obtain 26.51 g of dodecylbenzotriazole cationic compound. Its ¹ HNMR spectrum is shown in FIG. 1 .

Example 4:

Take 14.8 g (0.124 mol) of benzotriazole and dissolve it in 100 ml of distilled water. Add 6 g of NaOH (0.15 mol), stir and heat. NaOH is completely dissolved, add 39.7.g (0.13mol) of hexadecane bromide, increase stirring, and keep the reaction temperature at 60-80°C. After 24 hours of reaction, distill the solvent, and wash the excess benzotriazole with heated water. Divided into a water layer and an oil layer, the water layer was separated to obtain an oil layer, and then dried with calcium chloride to obtain 26.5 g of the intermediate product N-hexadecylbenzotriazole.

Take 17.15g (0.05mol) of the intermediate product N-hexadecylbenzotriazole, use 70ml of water as a solvent, add it to a four-necked flask, control the temperature at 50°C, and add 12.6g (0.1mol) of dimethyl sulfate , stirred and reacted for 3 hours to obtain 28.31 g of hexadecylbenzotriazole cationic compound.

Determination of surface tension by ring method:

At 25°C, the CMC of dodecylbenzotriazole cationic compound is 2.0g/L, and the surface tension of water is reduced to 33.4mN/m.

Static weightlessness method:

At 30°C, the copper sheet was left to stand for three days in a sodium sulfate solution of pH=0, 0.2mol/L, and the corrosion inhibition efficiency IE of hexadecyl cationic compound to copper was 77.04% at 30 mg/L (compared to benzo Triazole is 52%).

At 40°C, No. 20 carbon steel was left standing in 1mol/L hydrochloric acid solution for 8 hours, and the corrosion inhibition efficiency IE of dodecyl cation compound on No. 20 carbon steel was 98.4% at 15 mg/L.

30 ℃, several alkyl benzotriazole compounds required minimum concentration table for 100% bactericidal rate of sulphate-reducing bacteria, saprophytic bacteria and heterotrophic bacteria

Claims (6)

1. compound with inhibition bactericidal action, its structural formula is:

R wherein ₁Be C _nH _2n+1, wherein n is 4～18, perhaps R ₁Be C ₆H ₅CH ₂

R ₂Be CH ₃, CH ₃CH ₂, CH ₂CH ₂OH, CH ₂COOH, C ₆H ₅CH ₂Or

X ₂Be (CH ₃) SO ₄, (CH ₃CH ₂) SO ₄, Cl or Br.

2. the preparation method of a compound as claimed in claim 1 the steps include:

A.. BTA is made solution with solvent, joins in the reaction vessel, and adding then with the BTA is the catalyzer of benchmark 1.0～1.5 mol ratios, stirs dissolving; Adding with the BTA is the alkylating reagent of benchmark 0.8～1.2 mol ratio again, stirring, heating reflux reaction, and steaming desolventizes, and adds water washing, separatory, drying obtains intermediate product N-alkyl BTA;

B. get above-mentioned intermediate product N-alkyl BTA, use dissolution with solvents, join in the reaction vessel, adding with intermediate product N-alkyl BTA is the quaternizing agent of benchmark 1-3 mol ratio, stirs, adds thermal response and reflux, and solvent distillation obtains product.

3. preparation method according to claim 2 is characterized in that described solvent is water or ethanol.

4. preparation method according to claim 2 is characterized in that the heating reflux reaction temperature is 50～60 ℃ in the steps A, and the reaction time is 20～24 hours; Reaction temperature is 50～80 ℃ among the step B; Reacting reflux time: 2～3h.

5. according to the described preparation method of claim 2, it is characterized in that described alkylating reagent is C _nH _2n+1X or C ₆H ₅CH ₂X, n:4-18 wherein, X is Cl, Br or I.

6. preparation method according to claim 2 is characterized in that described quaternizing agent is: dimethyl suflfate, dithyl sulfate, chlorethanol, epoxychloropropane, benzyl chloride, monoxone or bromoethane.

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