阅读说明：本技术 防止热轧酸洗钢表面发黑的缓蚀剂及其制备方法 (Corrosion inhibitor for preventing surface of hot-rolled pickled steel from blackening and preparation method thereof ) 是由 马颖 肖厚念 郎丰军 宋建红 程鹏 于 2021-06-24 设计创作，主要内容包括：本发明公开了一种防止热轧酸洗钢表面发黑的缓蚀剂及其制备方法,属于金属表面处理技术领域。该缓蚀剂为3-苯胺基-1-苯基丙酮、松香缩水甘油乙醇胺在酸催化下制得中间体,中间体与表面活性剂复配即得到缓蚀剂；其中,3-苯胺基-1-苯基丙酮与松香缩水甘油乙醇胺之间摩尔比为1:1～1:2；中间体与表面活性剂的摩尔比为1:1～1:1.5。本发明设计的缓蚀剂通过明显改善热轧酸洗钢由于晶界腐蚀严重而形成的沟壑状形貌,实现了解决热轧酸洗板酸洗后发黑的问题。(The invention discloses a corrosion inhibitor for preventing the surface of hot-rolled pickled steel from blackening and a preparation method thereof, belonging to the technical field of metal surface treatment. The corrosion inhibitor is prepared by preparing an intermediate from 3-anilino-1-phenyl acetone and rosin glycidyl ethanolamine under the catalysis of acid, and compounding the intermediate with a surfactant; wherein the molar ratio of the 3-anilino-1-phenyl acetone to the rosin glycidyl ethanolamine is 1: 1-1: 2; the molar ratio of the intermediate to the surfactant is 1: 1-1: 1.5. The corrosion inhibitor designed by the invention solves the problem that the hot-rolled pickled plate is blackened after being pickled by acid by obviously improving the gully-shaped appearance of the hot-rolled pickled steel due to serious grain boundary corrosion.)

1. The corrosion inhibitor for preventing the surface of hot-rolled pickled steel from blackening is characterized in that an intermediate is prepared from 3-anilino-1-phenyl acetone and rosin glycidyl ethanolamine under the catalysis of acid, and the intermediate is compounded with a surfactant to obtain the corrosion inhibitor;

wherein the molar ratio of the 3-anilino-1-phenyl acetone to the rosin glycidyl ethanolamine is 1: 1-1: 2;

the molar ratio of the intermediate to the surfactant is 1: 1-1: 1.5.

2. The corrosion inhibitor for preventing blackening of a surface of hot-rolled pickled steel according to claim 1, wherein the acid is one of concentrated sulfuric acid, perchloric acid, and tetrafluoroboric acid.

3. The corrosion inhibitor for preventing blackening of the surface of hot-rolled pickled steel as claimed in claim 1, wherein said surfactant is polyoxyethylene nonylphenyl ether.

4. The preparation method of the corrosion inhibitor for preventing the surface of the hot-rolled pickled steel from blackening is characterized by comprising the steps of uniformly mixing 3-anilino-1-phenyl acetone and rosin glycidyl ethanolamine at a molar ratio of 1: 1-1: 2, adding acid, reacting for 2-4 hours at 158-280 ℃ to form an intermediate, adding a surfactant into the intermediate, and stirring for 3-5 hours at room temperature to prepare the corrosion inhibitor, wherein the molar ratio of the intermediate to the surfactant is 1: 1-1: 1.5.

5. The method for preparing the corrosion inhibitor for preventing the surface of the hot-rolled pickled steel from blackening according to claim 4, wherein the acid is slowly added dropwise at a rate of 2 to 3 drops/s.

6. Use of the corrosion inhibitor according to claim 1 in hot-rolled pickled steel, characterized in that the corrosion inhibitor is added to a hydrochloric acid solution in an amount of 0.03 to 0.05%.

Technical Field

The invention relates to a corrosion inhibitor, belongs to the technical field of metal surface treatment, and particularly relates to a corrosion inhibitor for preventing blackening of the surface of hot-rolled pickled steel and a preparation method thereof.

Background

The hot-rolled pickled steel is an intermediate product between a hot-rolled plate and a cold-rolled plate, the quality requirement of the hot-rolled pickled steel is higher than that of the hot-rolled plate, and part of the hot-rolled pickled steel even needs to be produced according to the quality requirement of the cold-rolled plate. Compared with the common hot rolled plate, the hot-rolled pickled plate removes the iron oxide scales on the surface, improves the surface quality, and is convenient for welding, oiling, electrophoresis and paint spraying. The hot-rolled pickled plate is used for replacing a corresponding cold-rolled plate, so that the production cost of an enterprise can be saved. At present, hot-rolled pickled steel mainly comprises cold-forming steel, structural steel, automobile structural steel, enamel steel and the like, and is widely applied to the industry fields of automobiles, compressors, general-purpose machines and the like.

In the development and production process of hot-rolled pickled steel, the defect that the surface of a part of hot-rolled strip steel is blackened after being pickled is found, and the surface quality of a finished product is influenced. The defects gradually disappear after being rolled by cold rolling at a high reduction ratio, the influence on the surface quality of a finished product is small, but the defects have a large influence on hot-rolled pickled steel products which are 'cooled by heat'. The surface blackening defect not only affects the appearance of the product, but also has adverse effects on subsequent processing and use (stamping, welding, coating and the like) of the product, brings a series of problems in the process of customer application, causes complaints of users, and reduces the market competitiveness of the product.

The traditional corrosion inhibitor does not obviously improve the blackening problem of the hot-rolled pickled plate after acid cleaning. Therefore, the pickling corrosion inhibitor which has the advantages of small addition amount and high corrosion inhibition efficiency and can prevent the surface of the hot-rolled pickled steel from blackening is urgently needed to be developed.

Disclosure of Invention

In order to solve the technical problems, the invention provides the corrosion inhibitor for preventing the surface of the hot-rolled pickled steel from blackening and the preparation method thereof, and the corrosion inhibitor can obviously improve the gully-shaped appearance of the hot-rolled pickled steel due to serious grain boundary corrosion, thereby obviously improving the problem that the hot-rolled pickled plate which is cooled by heat instead of cold is blackened after pickling, and leading the surface of the pickled strip steel to be uniform, bright and white.

In order to achieve the purpose, the invention discloses a corrosion inhibitor for preventing the surface of hot-rolled pickled steel from blackening, which is prepared by preparing an intermediate from 3-anilino-1-phenyl acetone and rosin glycidyl ethanolamine under the catalysis of acid, and compounding the intermediate with a surfactant to obtain the corrosion inhibitor;

wherein the molar ratio of the 3-anilino-1-phenyl acetone to the rosin glycidyl ethanolamine is 1: 1-1: 2;

the molar ratio of the intermediate to the surfactant is 1: 1-1: 1.5.

Further, the acid is one of concentrated sulfuric acid, perchloric acid or tetrafluoroboric acid.

Further, the surfactant is polyoxyethylene nonyl phenyl ether.

Meanwhile, the invention also discloses a preparation method of the corrosion inhibitor for preventing the blackening of the surface of the hot-rolled pickled steel, which comprises the steps of uniformly mixing 3-anilino-1-phenyl acetone and rosin glycidyl ethanolamine at a molar ratio of 1: 1-1: 2, then adding acid, reacting for 2-4 hours at 158-280 ℃ to form an intermediate, adding a surfactant into the intermediate, and stirring for 3-5 hours at room temperature to prepare the corrosion inhibitor, wherein the molar ratio of the intermediate to the surfactant is 1: 1-1: 1.5.

Furthermore, the acid is slowly dripped at the dripping speed of 2-3 drops/s, so that the generation of side reactions is reduced.

In addition, the invention also discloses the application of the corrosion inhibitor in hot-rolled pickled steel, which comprises the step of adding the corrosion inhibitor into a hydrochloric acid solution, wherein the addition amount of the corrosion inhibitor is 0.03-0.05%.

The beneficial effects of the invention are mainly embodied in the following aspects:

1. the corrosion inhibitor designed by the invention has the advantages of relatively simple synthesis method, low usage amount and good use effect;

2. the corrosion inhibitor designed by the invention can prevent the steel plate from being damaged due to excessive pickling, reduce the grain boundary corrosion on the surface of the pickled steel plate, obviously improve the problem that the hot-rolled pickled steel plate which is cooled by hot pickling is blackened after pickling, ensure that the surface of the pickled steel plate is uniform and bright, and is beneficial to improving the yield.

3. The acid washing method designed by the invention is simple to operate, and is beneficial to reducing acid consumption and iron loss.

Drawings

FIG. 1 is a schematic view of the macro and micro structure of hot rolled pickled steel after treatment in a conventional pickling solution;

FIG. 2 is a schematic view of the macro and micro structure of the hot rolled pickled steel of FIG. 1 after treatment in a pickling solution as claimed herein;

FIG. 3 is a schematic view of the macro and micro structure of hot rolled pickled steel after treatment in a conventional pickling solution;

FIG. 4 is a schematic view of the macro and micro structure of the hot rolled pickled steel of FIG. 3 after treatment in the pickling solution as claimed herein.

Detailed Description

The invention discloses a corrosion inhibitor for preventing the surface of hot-rolled pickled steel from blackening, which is prepared by preparing an intermediate from 3-anilino-1-phenyl acetone and rosin glycidyl ethanolamine under the catalysis of acid, and compounding the intermediate with a surfactant; wherein the molar ratio of the 3-anilino-1-phenyl acetone to the rosin glycidyl ethanolamine is 1: 1-1: 2; the molar ratio of the intermediate to the surfactant is 1: 1-1: 1.5; the acid is one of concentrated sulfuric acid, perchloric acid or tetrafluoroboric acid, and the surfactant is polyoxyethylene nonyl phenyl ether.

The density of the concentrated sulfuric acid adopted by the invention is 1.84g cm^-3；

The perchloric acid used in the present invention has a density of 1.67g cm^-3；

The tetrafluoroboric acid adopted by the invention has the density of 1.38g cm^-3；

Meanwhile, the invention also discloses a preparation method of the corrosion inhibitor, which comprises the steps of uniformly mixing 3-anilino-1-phenyl acetone and rosin glycidyl ethanolamine at a molar ratio of 1: 1-1: 2, adding acid, reacting for 2-4 hours at 158-280 ℃ to form an intermediate, adding a surfactant into the intermediate, and stirring for 3-5 hours at room temperature to prepare the corrosion inhibitor, wherein the molar ratio of the intermediate to the surfactant is 1: 1-1: 1.5, and the acid is slowly dripped at a dripping speed of 2-3 drops/s.

The possible action principle of the corrosion inhibitor prepared by the invention is as follows:

according to the invention, 3-anilino-1-phenyl acetone is selected as a reaction raw material, one end of an intermediate obtained by the reaction of the 3-anilino-1-phenyl acetone and rosin glycidyl ethanolamine has anilino cations, and the other end of the intermediate has rosin glycidyl ester groups capable of playing a lubricating role, wherein the anilino cations are strongly attracted to the surface of metal Fe with a negative surface in a hydrochloric acid medium to generate remarkable physical adsorption, so that an isolation layer for blocking H + attack is formed, the corrosion rate of the metal is reduced, the rosin glycidyl ester groups can complex certain oxidants in a solution, the potential of the oxidant is reduced to achieve the purpose of slow release, the anilino cations and the oxidant are compounded to form coordination bonds, and the overlapping adsorption capacity is increased. And transverse attraction exists among the adsorption particles, so that the adsorption layer is compact and has good stability. Can obviously reduce the gully-shaped appearance formed on the surface of the steel plate after pickling due to serious grain boundary corrosion.

In order to better explain the invention, the following further illustrate the main content of the invention in connection with specific examples, but the content of the invention is not limited to the following examples.

Example 1

Adding 3-anilino-1-phenyl acetone and rosin glycidyl ethanolamine into a flask, uniformly mixing, adding acid, controlling the dropping speed to be 2-3 drops/s, reacting for 2 hours at 158 ℃, performing condensation reaction to form an intermediate, then adding polyoxyethylene nonyl phenyl ether, stirring at normal temperature, reacting for 3 hours, wherein the molar ratio of the 3-anilino-1-phenyl acetone to the rosin glycidyl ethanolamine is 1:1, the molar ratio of the intermediate to the polyoxyethylene nonyl phenyl ether is 1:1, and finally distilling to remove the solvent to obtain the corrosion inhibitor, wherein the yield is 90.2%.

Example 2

Compared with the example 1, the molar ratio of the 3-anilino-1-phenyl acetone to the rosin glycidyl ethanolamine is 1:1.2, the rest is kept the same, and the yield is 91.3%.

Example 3

Compared with the example 1, the molar ratio of the 3-anilino-1-phenyl acetone to the rosin glycidyl ethanolamine is 1:1.5, the rest is kept the same, and the yield is 90.4%.

Example 4

Compared with the example 1, the molar ratio of the 3-anilino-1-phenyl acetone to the rosin glycidyl ethanolamine is 1:1.7, the rest is kept the same, and the yield is 90.8%.

Example 5

The molar ratio of 3-anilino-1-phenylpropanone to rosin glycidylethanolamine was 1:2 compared to example 1, the other things remaining the same and the yield was 91.2%.

Example 6

The reaction temperature was 280 ℃ as compared with example 1, and the yield was 89.5% while keeping the same.

Example 7

The reaction temperature was 200 ℃ as compared with example 1, and the yield was 93.6% while keeping the same.

Example 8

The reaction temperature was 250 ℃ as compared with example 1, and the yield was 94.3% while keeping the same.

Example 9

Adding 3-anilino-1-phenyl acetone and rosin glycidyl ethanolamine into a flask, uniformly mixing, adding acid, controlling the dropping speed to be 2-3 drops/s, reacting for 4 hours at 158 ℃, performing condensation reaction to form an intermediate, then adding polyoxyethylene nonyl phenyl ether, stirring at normal temperature, reacting for 5 hours, wherein the molar ratio of the 3-anilino-1-phenyl acetone to the rosin glycidyl ethanolamine is 1:2, the molar ratio of the intermediate to the polyoxyethylene nonyl phenyl ether is 1:1.5, and finally distilling to remove the solvent to obtain the corrosion inhibitor, wherein the yield is 95.2%.

Example 10

The molar ratio of the intermediate to polyoxyethylene nonylphenyl ether was 1:1.2, which remained the same as in example 9, giving a yield of 93.6%.

Example 11

The reaction temperature was 200 ℃ as compared with example 9, and the yield was 94.5% while keeping the same.

The corrosion inhibitor prepared in the above example 1 was added to a common hydrochloric acid in an amount of 0.03% to prepare a pickling solution.

Respectively placing the hot-rolled pickled steel I and the hot-rolled pickled steel II in common hydrochloric acid and pickling solution, controlling the pickling temperature to be 70-80 ℃ and the pickling speed to be 40-120 m/min; the obtained pickled steel plates are shown in FIG. 1, FIG. 2, FIG. 3 and FIG. 4, respectively;

as can be seen from fig. 1 to 4, the two hot-rolled pickled steels adopted in the present invention have blackened surfaces after conventional pickling, and the micro-topography of the steel shows that the steel has an obvious gully shape, and after the corrosion inhibitor of the present invention is added, the micro-topography of the pickled steel becomes flat, and the surface of the substrate is obviously bright and white. The corrosion inhibitor adopted by the design has good corrosion inhibition effect on the premise of low usage amount, and the corrosion inhibition rate can reach more than 98%.

The above examples are merely preferred examples and are not intended to limit the embodiments of the present invention. In addition to the above embodiments, the present invention has other embodiments. All technical solutions formed by adopting equivalent substitutions or equivalent transformations fall within the protection scope of the claims of the present invention.