A hydrogen peroxide stabilizer for stainless steel cleaning agent and its preparation method and application

Abstract

The present invention relates to the field of stainless steel cleaning technology, and specifically to a hydrogen peroxide stabilizer for stainless steel cleaning agents, a preparation method and an application thereof. The present invention selects three cyclodextrins and compounds with fatty alcohol polyoxyethylene ether, polyacrylic acid and polyethylene glycol, and utilizes the configuration and segment characteristics of different high molecular polymers to achieve the capture and masking of various metal impurity ions, thereby avoiding the decomposition of hydrogen peroxide under the catalysis of metals, resulting in a decrease in effective concentration. The use of the hydrogen peroxide oxidant of the present invention can enable hydrogen peroxide to maintain excellent stability in high-temperature storage, transportation and stainless steel cleaning and other usage scenarios, which is conducive to improving the quality of industrial products and reducing costs.

Description

Technical Field

[0001] The invention relates to the field of stainless steel cleaning technology, in particular to the field under IPC classification number C01B15 / 037, and more specifically to a hydrogen peroxide stabilizer for stainless steel cleaning agent and a preparation method and application thereof. Background Art

[0002] In the stainless steel cleaning process, hydrogen peroxide is needed. Its main function is to undergo an oxidation-reduction reaction with the cleaning bath liquid and adjust the oxidation-reduction potential of the bath liquid to obtain the desired cleaning and passivation effect.

[0003] However, hydrogen peroxide is prone to decomposition under the catalysis of high temperature, metal impurities and other factors, which reduces the effective concentration. Especially during long-distance high-temperature transportation and long-term high-temperature storage, its stability is even worse, and the effective concentration will be further reduced. The oxidizing ability and oxidation effect of hydrogen peroxide are directly affected by the concentration. The lower the concentration, the worse the oxidizing ability, which will not only make it less effective in regulating the redox point, affecting the cleaning effect, and ultimately affecting the quality of the product, increasing the unqualified rate, but also increase the consumption of hydrogen peroxide and increase production costs.

[0004] At present, in actual production, the common method to prevent hydrogen peroxide from decomposing is to add a hydrogen peroxide stabilizer to mask the metal impurity ions. Prior art CN103896217B discloses a stabilizer for hydrogen peroxide, which is mainly composed of organic phosphonic acid or its salt, and complexes metal ions to prevent them from producing catalytic effects; but the required dosage is too large. If used in industrial production, more organic phosphorus wastewater is generated, the cost is high and the environmental protection is poor; especially in the stainless steel cleaning process, the composition of the tank liquid is complex, and the cleaning temperature is high. The acidic and high temperature environment is not conducive to the stability of the complex, and the temperature requirements for the storage and transportation environment are also high, which is not suitable for industrial production. Summary of the invention

[0005] In view of the defects of the prior art, the object of the present invention is to provide a hydrogen peroxide stabilizer for stainless steel cleaning agents which is low in cost, convenient and efficient and can mask a variety of metal ions.

[0006] On the other hand, the present invention also aims to provide a method for preparing the above-mentioned hydrogen peroxide stabilizer for stainless steel cleaning agent.

[0007] On the other hand, the present invention also aims to provide an application of the above-mentioned hydrogen peroxide stabilizer for stainless steel cleaning agent.

[0008] In order to achieve the above-mentioned object of the invention, the present invention adopts the following technical solutions:

[0009] A hydrogen peroxide stabilizer for stainless steel cleaning agent comprises the following raw materials: cyclodextrin, fatty alcohol polyoxyethylene ether, polyacrylic acid, polyethylene glycol, defoaming agent and water.

[0010] Preferably, the raw materials, by mass percentage, include 0.1-20% cyclodextrin, 0.5-1% fatty alcohol polyoxyethylene ether, 0.05-5% polyacrylic acid, 1-5% polyethylene glycol, and 0.001-0.05% defoaming agent; more preferably, the balance is water.

[0011] Preferably, the cyclodextrin includes two or more of α-cyclodextrin, β-cyclodextrin and γ-cyclodextrin.

[0012] Preferably, the cyclodextrin is a combination of α-cyclodextrin, β-cyclodextrin and γ-cyclodextrin.

[0013] Preferably, the raw materials include, by mass ratio, 0.5-5% of α-cyclodextrin, 0.1-5% of β-cyclodextrin and 1-10% of γ-cyclodextrin.

[0014] The present invention selects cyclodextrin, which has a ring structure and can capture metal ions and fix the metal ions inside the ring, thereby preventing the metal ions from contacting with hydrogen peroxide to activate and decompose them. The present invention also specifically combines three different cyclodextrins. The rings formed by different cyclodextrins have different sizes, and the affinity and capture ability for different metal ions are also different. The combination of the three cyclodextrins can achieve the capture and masking of various metal ions, and the requirements in different usage scenarios can be met by adjusting the proportions.

[0015] Preferably, the fatty alcohol polyoxyethylene ether is a C8-14 alcohol polyoxyethylene ether with an EO number of 20 to 30;

[0016] Further preferably, the fatty alcohol polyoxyethylene ether is a C8-12 alcohol polyoxyethylene ether with an EO number of 20 to 25;

[0017] More preferably, the fatty alcohol polyoxyethylene ether is lauryl alcohol polyoxyethylene ether, and the EO number is 25.

[0018] The inventors have found that the ability of cyclodextrin alone to capture metal ions is limited. In order to improve the stabilizing performance of the stabilizer on hydrogen peroxide, the present invention specifically adds fatty alcohol polyoxyethylene ether. The fatty alcohol polyoxyethylene ether with a higher carbon number and EO number has a soft chain segment and has a strong ability to capture and adsorb metal ions. After capturing the metal ions, the molecular chain is wound into a coil shape, which has a good masking effect on the metal ions and effectively prevents the degradation of hydrogen peroxide.

[0019] Preferably, the molecular weight of the polyacrylic acid is 1000 to 10000;

[0020] Further preferably, the molecular weight of the polyacrylic acid is 5000;

[0021] Preferably, the molecular weight of the polyethylene glycol is 5000-20000;

[0022] Further preferably, the molecular weight of the polyethylene glycol is 10000;

[0023] Taking into account the complexity of actual application scenarios, the present invention further adds PAA (polyacrylic acid) and PEG (polyethylene glycol) with larger molecular weights. PAA and PEG with higher molecular weights have longer molecular chains and can encapsulate larger metal impurities, further supplementing the size limitations of cyclodextrin and fatty alcohol polyoxyethylene ether, so that the hydrogen peroxide stabilizer of the present invention can maintain good stability of hydrogen peroxide even in the stainless steel cleaning process.

[0024] Preferably, the defoamer is a water-soluble defoamer;

[0025] Further preferably, the defoaming agent is Foam Ban HP 720 purchased from Münzing Chemie.

[0026] Another aspect of the present invention provides a method for preparing the above-mentioned hydrogen peroxide stabilizer for stainless steel cleaning agent, comprising the following steps:

[0027] S1: adding cyclodextrin into water, heating and stirring until completely dissolved, and cooling to obtain a cyclodextrin solution;

[0028] S2: adding fatty alcohol polyoxyethylene ether, polyacrylic acid and polyethylene glycol to the cyclodextrin solution, stirring until completely dissolved, to obtain a mixed solution;

[0029] S3: Add the defoamer into the mixed solution and stir until it is evenly dispersed.

[0030] Preferably, the heating temperature in step S1 is 40-70°C; more preferably, it is 50°C.

[0031] Preferably, the stirring temperature in steps S2 and S3 is room temperature.

[0032] Another aspect of the present invention provides the above hydrogen peroxide stabilizer for stainless steel cleaning agent, or the use of the hydrogen peroxide stabilizer prepared by the above preparation method, which is used for adding to hydrogen peroxide used in the stainless steel cleaning process.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] 1. The hydrogen peroxide stabilizer of the present invention can effectively improve the stability of hydrogen peroxide in high-temperature storage and transportation, as well as in actual application scenarios, and can maintain a stability of more than 90% when stored at 100°C for more than 24 hours;

[0035] 2. Hydrogen peroxide stabilizer of the present invention for Fe 2+ , Mn 2+ , Cu 2+ Cr 3+ Various metal ions can achieve good masking effect and can be applied to various production scenarios;

[0036] 3. The hydrogen peroxide stabilizer of the present invention has stable properties and can still achieve good hydrogen peroxide stability even in the presence of multiple additives such as cleaning agents, cosolvents, and biological enzymes;

[0037] 4. The hydrogen peroxide stabilizer of the present invention is adapted to different application scenarios by selecting the component content and the molecular weight of PAA and PEG;

[0038] 5. The raw materials of the hydrogen peroxide stabilizer of the present invention are easily available and easy to prepare, and are suitable for industrial production. DETAILED DESCRIPTION

[0039] Example 1

[0040] The present embodiment provides a hydrogen peroxide stabilizer for a stainless steel cleaning agent, which includes the following raw materials by mass ratio: 4.675% α-cyclodextrin (purchased from Sinopharm Chemical Reagent Co., Ltd.), 0.935% β-cyclodextrin (purchased from Sinopharm Chemical Reagent Co., Ltd.), 9.35% γ-cyclodextrin (purchased from Sinopharm Chemical Reagent Co., Ltd.), 0.75% lauryl alcohol polyoxyethylene ether (C12-EO25, purchased from Jiangsu Hai'an Petrochemical Plant, Haishihua brand MOA series), 1.75% polyacrylic acid with a molecular weight of 5000 (purchased from Daochuang Chemical, brand PAA5000), 2% polyethylene glycol with a molecular weight of 10000 (purchased from Sinopharm Chemical Reagent Co., Ltd.), 0.001% defoaming agent Foam Ban HP 720 (purchased from Münzing Chemie), and deionized water makes up the balance.

[0041] This embodiment also provides a method for preparing the above-mentioned hydrogen peroxide stabilizer for stainless steel cleaning agent, comprising the following steps:

[0042] S1: adding α-cyclodextrin, β-cyclodextrin and γ-cyclodextrin according to mass percentage into deionized water, heating to 50° C., stirring until completely dissolved, and cooling to obtain a cyclodextrin solution;

[0043] S2: adding lauryl alcohol polyoxyethylene ether, polyacrylic acid and polyethylene glycol into the cyclodextrin solution according to mass percentage, stirring at 25° C. until completely dissolved, to obtain a mixed solution;

[0044] S3: Add the defoamer into the mixed solution and stir at 25°C until it is evenly dispersed.

[0045] This embodiment also provides an application of the above hydrogen peroxide stabilizer for stainless steel cleaning agent, which is used to be added to the hydrogen peroxide used in the stainless steel cleaning process.

[0046] Example 2

[0047] The present embodiment provides a hydrogen peroxide stabilizer for a stainless steel cleaning agent, which includes the following raw materials, by mass ratio: 2.75% α-cyclodextrin, 0.55% β-cyclodextrin, 5.5% γ-cyclodextrin, 0.75% lauryl alcohol polyoxyethylene ether (C12-EO25), 1.75% polyacrylic acid with a molecular weight of 5000, 2% polyethylene glycol with a molecular weight of 10000, 0.05% defoaming agent, and deionized water makes up the balance.

[0048] The purchasing sources of each reagent are the same as those in Example 1.

[0049] This embodiment also provides a method for preparing the above-mentioned hydrogen peroxide stabilizer for stainless steel cleaning agent, which is the same as that of Example 1.

[0050] Example 3

[0051] The present embodiment provides a hydrogen peroxide stabilizer for a stainless steel cleaning agent, which includes the following raw materials, by mass ratio: 4.125% α-cyclodextrin, 0.825% β-cyclodextrin, 8.25% γ-cyclodextrin, 0.75% lauryl alcohol polyoxyethylene ether (C12-EO25), 1.75% polyacrylic acid with a molecular weight of 500 (purchased from Dao Chuang Chemical, brand PAA500), 2% polyethylene glycol with a molecular weight of 1000, 0.001% defoaming agent, and deionized water makes up the balance.

[0052] The purchase sources of the reagents not otherwise indicated are the same as those in Example 1.

[0053] This embodiment also provides a method for preparing the above-mentioned hydrogen peroxide stabilizer for stainless steel cleaning agent, which is the same as that of Example 1.

[0054] Performance Testing

[0055] 1. Hydrogen peroxide stability test under simulated storage and transportation conditions

[0056] Test sample: 99.1wt% hydrogen peroxide (commercially available 28% industrial high-quality hydrogen peroxide), 0.6wt% special additives, 0.3wt% hydrogen peroxide stabilizer of Examples 1 to 3 or Control Example (commercially available hydrogen peroxide stabilizer aminotrimethylenephosphonic acid ATMP, purchased from Sinopharm Chemical Reagent Co., Ltd.) are mixed; wherein the composition of the special additive, by mass percentage, is: 20% sulfuric acid, 0.5% ethylene glycol monobutyl ether, 0.05% disodium EDTA, 0.05% glucose, and deionized water is added to make up the balance to 100%.

[0057] Test method: After the test sample is diluted 100 times with deionized water, it is stored in an oven at 100°C for 5h, 10h, 24h and 72h respectively to accelerate the simulation of hydrogen peroxide transportation and storage process, measure the hydrogen peroxide concentration at different storage times, and calculate the stability of hydrogen peroxide.

[0058] Method for determining hydrogen peroxide concentration: Use the titration method described in HG / T 4916-2016, that is, use 0.1 mol / L potassium permanganate standard titration solution to titrate until the solution turns pink and does not disappear within 30 seconds, which is the end point. The consumed potassium permanganate is converted to obtain the hydrogen peroxide concentration in mol / L. The titration reaction stoichiometric equation is: 2KMnO4+3H2O2→2MnO2+2KOH+3O2↑+2H2O.

[0059] The stability of hydrogen peroxide is calculated by the following formula:

[0060] Hydrogen peroxide stability = (test concentration c / initial concentration c0)*100%.

[0061] The stability of hydrogen peroxide is listed in Table 1.

[0062] 2. Hydrogen peroxide stability test in simulated application scenarios

[0063] Test sample: 99.05wt% hydrogen peroxide (commercially available 28% industrial high-quality hydrogen peroxide), 0.6wt% special additives, 0.05wt% simulated working fluid, 0.3wt% hydrogen peroxide stabilizer of Examples 1 to 3 or Control Example (commercially available hydrogen peroxide stabilizer aminotrimethylenephosphonic acid ATMP, purchased from Sinopharm Chemical Reagent Co., Ltd.); wherein the composition of the special additive, by mass percentage, is: 20% sulfuric acid, 0.5% ethylene glycol monobutyl ether, 0.05% disodium EDTA, 0.05% glucose, and deionized water is added to the balance to 100%; the composition of the simulated working fluid, by mass concentration of each solute, is: 20% Fe 2+ 、20%Mn 2+ 、20%Cu 2+ 、20%Cr 3+, 20% lipase (lipase from porcine pancreas, purchased from Sinopharm Chemical Reagent Co., Ltd.), each metal ion was added in the form of the corresponding nitrate, and the solvent was deionized water.

[0064] The test method refers to performance test 1, and the concentration of hydrogen peroxide after storage for 5h, 10h, and 24h is determined. The stability of hydrogen peroxide is calculated and the results are recorded in Table 1.

[0065] Table 1

[0066]

Claims

1. A hydrogen peroxide stabilizer for stainless steel cleaning agent, characterized in that: The invention comprises the following raw materials: cyclodextrin, fatty alcohol polyoxyethylene ether, polyacrylic acid, polyethylene glycol, defoaming agent and water; The raw materials, by mass percentage, include 0.1-20% cyclodextrin, 0.5-1% fatty alcohol polyoxyethylene ether, 0.05-5% polyacrylic acid, 1-5% polyethylene glycol, and 0.001-0.05% defoaming agent; According to the mass ratio, the cyclodextrin comprises 0.5-5% of α-cyclodextrin, 0.1-5% of β-cyclodextrin and 1-10% of γ-cyclodextrin.

2. The hydrogen peroxide stabilizer for stainless steel cleaning agent according to claim 1, characterized in that: The fatty alcohol polyoxyethylene ether is a C8-14 alcohol polyoxyethylene ether with an EO number of 20 to 30.

3. The hydrogen peroxide stabilizer for stainless steel cleaning agent according to claim 1, characterized in that: The molecular weight of the polyacrylic acid is 1,000 to 10,000.

4. The hydrogen peroxide stabilizer for stainless steel cleaning agent according to claim 1, characterized in that: The molecular weight of the polyethylene glycol is 5000-20000.

5. A method for preparing the hydrogen peroxide stabilizer for stainless steel cleaning agent according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1: adding cyclodextrin into water, heating and stirring until completely dissolved, and cooling to obtain a cyclodextrin solution; S2: adding fatty alcohol polyoxyethylene ether, polyacrylic acid and polyethylene glycol to the cyclodextrin solution, stirring until completely dissolved, to obtain a mixed solution; S3: Add the defoamer into the mixed solution and stir until it is evenly dispersed.

6. The method for preparing a hydrogen peroxide stabilizer for stainless steel cleaning agent according to claim 5, characterized in that: The heating temperature in the step S1 is 40-70°C.

7. Use of the hydrogen peroxide stabilizer for stainless steel cleaning agent according to any one of claims 1 to 4, or the hydrogen peroxide stabilizer prepared by the preparation method according to claim 5 or 6, characterized in that: Used to add to the hydrogen peroxide used in stainless steel cleaning processes.

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