Neutral steel rust conversion agent and preparation method thereof

Abstract

The invention provides a neutral steel rust conversion agent and a preparation method thereof, and the neutral steel rust conversion agent comprises sodium hydroxide and deionized water, and the following raw materials in parts by mass: 50-80 parts of organic acid, 10-30 parts of sodium gluconate, 5-15 parts of anhydrous sodium citrate, 3-7 parts of polyethylene glycol and 0.3-0.8 part of sodium dodecyl benzene sulfonate. By means of the method, the problems that in traditional strong acid rust removal, the rust removal process is complex, corrosion to a steel matrix is high, environment pollution is serious, the human body is harmed, and the wastewater treatment cost is high can be solved.

Description

Technical Field

[0001] The invention relates to the technical field of removing rust from steel surfaces, and more specifically, to a neutral steel rust removing agent and a preparation method thereof. Background Art

[0002] Iron and steel materials are widely used in various industries, but due to corrosion, the substrate is prone to rust and needs to be frequently derusted. At present, strong acid pickling is the main method for rust removal. Although the traditional strong acid pickling method has low cost and fast rust removal speed, it has safety and environmental protection issues. Strong acids are highly corrosive to metals and may cause excessive corrosion or even hydrogen embrittlement of the metal, affecting the mechanical properties of the material. In addition, acid mist will be generated during the strong acid rust removal process, which not only pollutes the environment, but may also cause harm to the human body, and also leads to high wastewater treatment costs. Summary of the invention

[0003] In view of the above problems, the purpose of the present invention is to provide a neutral steel rust removal agent and a preparation method thereof, so as to solve the problems existing in traditional strong acid rust removal, such as complex rust removal process, strong corrosion to steel substrate, serious environmental pollution, harm to human body and high wastewater treatment cost.

[0004] The present invention provides a neutral steel rust-removing agent, comprising: sodium hydroxide, deionized water, and the following raw materials in parts by mass:

[0005] 50-80 parts by weight of organic phosphonic acid, 10-30 parts by weight of sodium gluconate, 5-15 parts by weight of anhydrous sodium citrate, 3-7 parts by weight of polyethylene glycol, and 0.3-0.8 parts by weight of sodium dodecylbenzene sulfonate.

[0006] Preferably, the pH value of the sodium hydroxide adjustment solution is 5-7.

[0007] The present invention also provides a method for preparing a neutral steel rust-removing agent, which is used to prepare the neutral steel rust-removing agent. The method comprises:

[0008] According to the preset ratio, organic phosphonic acid, sodium citrate, deionized water, sodium hydroxide, sodium gluconate, sodium dodecylbenzene sulfonate, and polyethylene glycol are measured respectively;

[0009] The organic acid is placed in a preset volume of the deionized water and stirred until completely dissolved, the sodium hydroxide is added to adjust the solution to a neutral solution, and stirred for a preset time;

[0010] According to a preset ratio, the sodium citrate, the sodium gluconate, the sodium dodecylbenzene sulfonate and the polyethylene glycol are added to the neutral solution, and stirred for a preset time until the solution is uniform;

[0011] Add one third of the preset volume of deionized water to the uniformly stirred solution, and stir for a preset time to obtain a neutral steel rust-removing agent.

[0012] Preferably, the pH value of the neutral solution is 5-7.

[0013] Preferably, the organic acid is placed in a preset volume of deionized water and stirred until completely dissolved, and the stirring preset time when the sodium hydroxide is added to adjust the solution to become a neutral solution is not less than 15 minutes, the stirring temperature is room temperature, and the stirring speed is 200-300 r / min.

[0014] Preferably, the sodium citrate, the sodium gluconate, the sodium dodecylbenzene sulfonate and the polyethylene glycol are added to the neutral solution and stirred for a preset time until the solution is uniform, the preset stirring time is not less than 15 minutes, the stirring temperature is room temperature, and the stirring speed is 200-300 r / min.

[0015] Preferably, one third of the preset volume of deionized water is added to the uniformly stirred solution, and the stirring time is not less than 15 minutes, the stirring temperature is room temperature, and the stirring speed is 200-300 r / min.

[0016] It can be seen from the above technical scheme that the neutral steel rust-removing agent and the preparation method thereof provided by the present invention can achieve the following beneficial effects compared with the prior art:

[0017] (1) Compared with strong acid pickling, near-neutral rust remover is more environmentally friendly and can reduce the health risks to operators and pollution to the environment.

[0018] (2) During the rust removal process, neutral rust removers will not cause hydrogen embrittlement and can maintain the mechanical properties of steel.

[0019] (3) In the long run, neutral steel rust removers will bring higher economic benefits due to reduced maintenance times and extended coating life.

[0020] (4) The preparation process of the neutral steel rust removal agent is simple; during rust removal construction, since there is no need for complex surface pretreatment of steel, the process is simpler and faster, which helps to improve construction efficiency.

[0021] (5) After the steel surface is treated with a neutral steel rust remover, its surface is compatible with a variety of paints and coatings, providing convenience for subsequent painting work.

[0022] (6) The use of neutral steel rust remover can effectively remove the rust on the surface of cast steel and generate complexes to protect the internal steel; the corrosion resistance of rusted steel treated with the rust remover is significantly improved, which is manifested as an increase in impedance value, so it has better protection effect and longer durability.

[0023] In order to achieve the above and related purposes, one or more aspects of the present invention include the features that will be described in detail later. The following description and the accompanying drawings describe some exemplary aspects of the present invention in detail. However, these aspects indicate only some of the various ways in which the principles of the present invention can be used. In addition, the present invention is intended to include all these aspects and their equivalents. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] By referring to the following description in conjunction with the accompanying drawings, and with a more comprehensive understanding of the present invention, other objects and results of the present invention will become more apparent and easy to understand. In the accompanying drawings:

[0025] Figure 1 The present invention is a flow chart of a method for preparing a neutral steel rust-removing agent according to an embodiment of the present invention.

[0026] Figure 2 Schematic diagram of the steel surface without the application of neutral steel rust remover.

[0027] Figure 3 This is a schematic diagram of the steel surface after applying neutral steel rust remover for 5 minutes.

[0028] The same reference numerals throughout the drawings indicate similar or corresponding features or functions. DETAILED DESCRIPTION

[0029] In the following description, for the purpose of illustration, in order to provide a comprehensive understanding of one or more embodiments, many specific details are set forth. However, it is apparent that these embodiments may also be implemented without these specific details. In other examples, for ease of describing one or more embodiments, known structures and devices are shown in the form of block diagrams.

[0030] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0031] In view of the aforementioned problems of the traditional strong acid rust removal, such as the complicated rust removal process, strong corrosion to the steel substrate, serious environmental pollution, harm to the human body, and high cost of wastewater treatment, the present invention provides a neutral steel rust removal agent and a preparation method thereof. The present invention uses HEDP (organic phosphonic acid), sodium citrate, deionized water, sodium hydroxide, sodium gluconate, sodium dodecylbenzene sulfonate and polyethylene glycol to synergistically prepare a steel rust removal agent with a pH close to neutral. The solution can effectively remove the rust on the surface of cast steel and generate a complex to protect the internal steel. The method is simple, low in cost, and the preparation process is also very convenient. It can not only effectively remove rust to generate a protective film to further protect the steel, but is also environmentally friendly and harmless, and will not weaken the mechanical properties of steel, and is very suitable for large-scale industrial production.

[0032] The invention provides a neutral steel rust-removing agent, which comprises sodium hydroxide, deionized water, and the following raw materials in parts by weight: 50-80 parts by weight of organic acid, 10-30 parts by weight of sodium gluconate, 5-15 parts by weight of anhydrous sodium citrate, 3-7 parts by weight of polyethylene glycol, and 0.3-0.8 parts by weight of sodium dodecylbenzene sulfonate.

[0033] The pH value of the sodium hydroxide adjustment solution is 5-7.

[0034] Figure 1 The preparation method of the neutral steel rust-removing agent according to an embodiment of the present invention is shown. Figure 1 As shown, the present invention provides a method for preparing a neutral steel rust-removing agent, which is used for the above-mentioned neutral steel rust-removing agent, and the preparation method comprises the following steps:

[0035] S1: According to the preset ratio, measure organic phosphonic acid, sodium citrate, deionized water, sodium hydroxide, sodium gluconate, sodium dodecylbenzene sulfonate, and polyethylene glycol respectively;

[0036] S2: placing the organic acid in a preset volume of deionized water and stirring until it is completely dissolved, adding the sodium hydroxide to adjust the solution to a neutral solution, and stirring for a preset time;

[0037] S3: adding the sodium citrate, the sodium gluconate, the sodium dodecylbenzene sulfonate and the polyethylene glycol to the neutral solution according to a preset ratio, and stirring for a preset time until the solution is uniform;

[0038] S4: adding one third of the preset volume of deionized water to the uniformly stirred solution, and stirring for a preset time to obtain a neutral steel rust remover.

[0039] In step S2, the pH value of the neutral solution is 5-7. In the process of placing the organic acid in the preset volume of the deionized water and stirring until it is completely dissolved, and adding the sodium hydroxide to adjust the solution to become a neutral solution, the preset stirring time is not less than 15 minutes, the stirring temperature is room temperature, and the stirring speed is 200-300 r / min.

[0040] In step S3, the sodium citrate, the sodium gluconate, the sodium dodecylbenzene sulfonate and the polyethylene glycol are added to the neutral solution and stirred for a preset time until the solution is uniform. The preset stirring time is not less than 15 minutes, the stirring temperature is room temperature, and the stirring speed is 200-300 r / min.

[0041] In step S4, one third of the preset volume of deionized water is added to the uniformly stirred solution, and the solution is stirred for a preset time, wherein the preset stirring time is not less than 15 minutes, the stirring temperature is room temperature, and the stirring speed is 200-300 r / min.

[0042] In the embodiment of the present invention, the prepared neutral steel rust-removing agent can effectively remove the rust on the surface of cast steel and generate a complex to protect the internal steel. The preparation method is simple, low cost, and the preparation process is very convenient. It can not only effectively remove the rust to generate a protective film to further protect the steel, but also be environmentally friendly and harmless, and will not weaken the mechanical properties of steel, and is very suitable for industrial large-scale production. Figure 2 and Figure 3 The figure shows the comparison before and after the prepared neutral steel rust-removing agent is applied to the steel surface. Figure 2 This is a picture of uncoated neutral steel rust remover. Figure 3 This is the picture taken 5 minutes after applying the neutral steel rust remover. It can be seen that the neutral steel rust remover can effectively remove the rust on the surface of cast steel.

[0043] The present invention is further described in detail below in conjunction with the embodiments and drawings. It should be pointed out that the embodiments described below are intended to facilitate the understanding of the present invention and do not have any limiting effect on the present invention.

[0044] Example 1

[0045] The specific formula includes 50g of 1-hydroxyethyl diphosphonic acid (HEDP), 10g of sodium gluconate, 5g of sodium citrate, 3g of polyethylene glycol, 0.5g of sodium dodecylbenzene sulfonate, sodium hydroxide is used to adjust the pH to 5, and the solvent is 1L of deionized water.

[0046] The steps of preparing the neutral steel rust-removing agent material according to the above formula are as follows:

[0047] Step 1, HEDP, sodium citrate, deionized water, sodium hydroxide, sodium gluconate, sodium dodecylbenzene sulfonate and polyethylene glycol are measured respectively;

[0048] Step 2: Place the HEDP material referred to in step 1 in a 0.75L deionized water beaker and stir until it is completely dissolved, then add sodium hydroxide to make the pH between 5-7, stir for no less than 15 minutes, stir at room temperature, and stir at a rate of 300r / min;

[0049] Step 3, adding sodium citrate, sodium gluconate, sodium dodecylbenzene sulfonate and polyethylene glycol to the neutral solution obtained in step 2 in sequence according to the set combination, and stirring evenly, the stirring time is not less than 15 minutes, the stirring temperature is room temperature, and the stirring rate is 300r / min;

[0050] Step 4: Add 0.25 L of deionized water to the solution obtained in step 3, and continue stirring for no less than 15 minutes at room temperature and a stirring rate of 300 r / min to obtain a nearly neutral steel rust-removing agent.

[0051] Example 2

[0052] The specific formula includes 55g of 1-hydroxyethyl diphosphonic acid (HEDP), 15g of sodium gluconate, 6g of sodium citrate, 3g of polyethylene glycol, 0.5g of sodium dodecylbenzene sulfonate, sodium hydroxide is used to adjust the pH to 5, and the solvent is 1L of deionized water.

[0053] The steps of preparing the neutral steel rust-removing agent material according to the above formula are as follows:

[0054] Step 1, HEDP, sodium citrate, deionized water, sodium hydroxide, sodium gluconate, sodium dodecylbenzene sulfonate and polyethylene glycol are measured respectively;

[0055] Step 2: Place the HEDP material referred to in step 1 in a 0.75L deionized water beaker and stir until it is completely dissolved, then add sodium hydroxide to make the pH at 6, stir for no less than 20 minutes, at room temperature, and at a stirring rate of 300 r / min;

[0056] Step 3, adding sodium citrate, sodium gluconate, sodium dodecylbenzene sulfonate and polyethylene glycol to the neutral solution obtained in step 2 in sequence according to the set combination, and stirring evenly, the stirring time is not less than 20 minutes, the stirring temperature is room temperature, and the stirring rate is 300r / min;

[0057] Step 4: Add 0.25 L of deionized water to the solution obtained in step 3, and continue stirring for no less than 20 minutes at room temperature and a stirring rate of 300 r / min to obtain a nearly neutral steel rust-removing agent.

[0058] Example 3

[0059] The specific formula includes 60g of 1-hydroxyethyl diphosphonic acid (HEDP), 20g of sodium gluconate, 6g of sodium citrate, 4g of polyethylene glycol, 0.5g of sodium dodecylbenzene sulfonate, sodium hydroxide is used to adjust the pH to 5, and the solvent is 1L of deionized water.

[0060] The steps of preparing the neutral steel rust-removing agent material according to the above formula are as follows:

[0061] Step 1, HEDP, sodium citrate, deionized water, sodium hydroxide, sodium gluconate, sodium dodecylbenzene sulfonate and polyethylene glycol are measured respectively;

[0062] Step 2: Place the HEDP material referred to in step 1 in a 0.75L deionized water beaker and stir until it is completely dissolved, then add sodium hydroxide to make the pH between 5-7, stir for no less than 15 minutes, stir at room temperature, and stir at a rate of 300r / min;

[0063] Step 3, adding sodium citrate, sodium gluconate, sodium dodecylbenzene sulfonate and polyethylene glycol to the neutral solution obtained in step 2 in sequence according to the set combination, and stirring evenly, the stirring time is not less than 15 minutes, the stirring temperature is room temperature, and the stirring rate is 300r / min;

[0064] Step 4: Add 0.25 L of deionized water to the solution obtained in step 3, and continue stirring for no less than 15 minutes at room temperature and a stirring rate of 300 r / min to obtain a nearly neutral steel rust-removing agent.

[0065] Example 4

[0066] The specific formula includes 70g of 1-hydroxyethyl diphosphonic acid (HEDP), 25g of sodium gluconate, 5g of sodium citrate, 5g of polyethylene glycol, 0.5g of sodium dodecylbenzene sulfonate, sodium hydroxide is used to adjust the pH to 5, and the solvent is 1L of deionized water.

[0067] The steps of preparing the neutral steel rust-removing agent material according to the above formula are as follows:

[0068] Step 1, HEDP, sodium citrate, deionized water, sodium hydroxide, sodium gluconate, sodium dodecylbenzene sulfonate and polyethylene glycol are measured respectively;

[0069] Step 2: Place the HEDP material referred to in step 1 in a 0.75L deionized water beaker and stir until it is completely dissolved, then add sodium hydroxide to make the pH between 5-7, stir for no less than 15 minutes, stir at room temperature, and stir at a rate of 300r / min;

[0070] Step 3, adding sodium citrate, sodium gluconate, sodium dodecylbenzene sulfonate and polyethylene glycol to the neutral solution obtained in step 2 in sequence according to the set combination, and stirring evenly, the stirring time is not less than 15 minutes, the stirring temperature is room temperature, and the stirring rate is 300r / min;

[0071] Step 4: Add 0.25 L of deionized water to the solution obtained in step 3, and continue stirring for no less than 15 minutes at room temperature and a stirring rate of 300 r / min to obtain a nearly neutral steel rust-removing agent.

[0072] The above descriptions are only optional embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the contents of the present invention's specification and drawings, or directly / indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A neutral steel rust remover, characterized in that: include: Sodium hydroxide, deionized water, and the following raw materials in parts by mass: 50-80 parts by weight of organic phosphonic acid, 10-30 parts by weight of sodium gluconate, 5-15 parts by weight of anhydrous sodium citrate, 3-7 parts by weight of polyethylene glycol, and 0.3-0.8 parts by weight of sodium dodecylbenzene sulfonate.

2. The neutral steel rust-removing agent according to claim 1, characterized in that: The pH value of the sodium hydroxide adjustment solution is 5-7.

3. A method for preparing a neutral steel rust-removing agent, characterized in that: Used to prepare the neutral steel rust-removing agent as claimed in claim 1 or 2, the preparation method comprising: According to the preset ratio, organic phosphonic acid, sodium citrate, deionized water, sodium hydroxide, sodium gluconate, sodium dodecylbenzene sulfonate, and polyethylene glycol are measured respectively; The organic acid is placed in a preset volume of deionized water and stirred until completely dissolved, the sodium hydroxide is added to adjust the solution to a neutral solution, and stirred for a preset time; According to a preset ratio, the sodium citrate, the sodium gluconate, the sodium dodecylbenzene sulfonate and the polyethylene glycol are added to the neutral solution, and stirred for a preset time until the solution is uniform; Add one third of the preset volume of deionized water to the uniformly stirred solution, and stir for a preset time to obtain a neutral steel rust-removing agent.

4. The method for preparing the neutral steel rust-removing agent according to claim 3, characterized in that: The pH value of the neutral solution is 5-7.

5. The method for preparing the neutral steel rust-removing agent according to claim 3, characterized in that: The organic acid is placed in a preset volume of deionized water and stirred until completely dissolved. When the sodium hydroxide is added to adjust the solution to a neutral solution, the preset stirring time is not less than 15 minutes, the stirring temperature is room temperature, and the stirring speed is 200-300 r / min.

6. The method for preparing the neutral steel rust-removing agent according to claim 3, characterized in that: The sodium citrate, the sodium gluconate, the sodium dodecylbenzene sulfonate and the polyethylene glycol are added to the neutral solution, and stirred for a preset time until the solution is uniform. The preset stirring time is not less than 15 minutes, the stirring temperature is room temperature, and the stirring speed is 200-300 r / min.

7. The method for preparing the neutral steel rust-removing agent according to claim 3, characterized in that: Add one third of the preset volume of deionized water to the uniformly stirred solution, and stir for a preset time of not less than 15 minutes, the stirring temperature is room temperature, and the stirring speed is greater than 200-300 r / min.

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