A liquid cleaning agent with micron-sized pores, and a preparation method and application thereof

Abstract

This invention discloses a liquid cleaning agent for micron-sized pores, its preparation method, and its application. The raw materials, by weight percentage, include 20-30% hydroxy acid detergent, 2-3% corrosion inhibitor, 3-5% chelating agent, 0.1-0.5% surfactant, 1-3% penetrant, and deionized water to 100%. This invention utilizes a hydroxy acid detergent combined with a penetrant to rapidly penetrate the micron-sized micropores of ceramic filter plates, achieving deep cleaning of these pores. The use of a citric acid and gluconic acid dihydroxy organic acid compound system significantly improves the system's low-temperature solubility, preventing low-temperature crystallization. It is free of hydrofluoric acid, phosphorus-containing additives, and organic solvents, resulting in low chemical oxygen demand in post-treatment, aligning with green industrial development trends. This invention achieves a comprehensive breakthrough in meeting five core requirements: deep and efficient cleaning, zero corrosion protection, ultra-long storage stability, ultra-low foaming compatibility, and full environmental compliance, resulting in excellent overall performance.

Description

Technical Field

[0001] This invention relates to the field of detergent compositions, specifically to a liquid cleaning agent with micron-sized pores, its preparation method, and its application. Background Technology Micron-sized pores, due to their small diameter, are easily clogged by fine mineral particles, metal hydroxides, colloidal suspensions, oil flocculants, and microbial slime during filtration. Existing liquid cleaning agents are inefficient at cleaning micron-sized pores, exhibiting low flux recovery rates and often requiring heating before use. Deep micron-sized pores are particularly prone to secondary clogging. Currently, strong acids are commonly used for direct cleaning, which can easily corrode filter plates and equipment. Furthermore, post-treatment of cleaning agents results in high chemical oxygen demand (COD), posing significant environmental challenges. Therefore, developing a highly efficient, environmentally friendly, and non-corrosive liquid cleaning agent is crucial.

[0002] Chinese invention patent CN113174294B discloses a special cleaning agent for ceramic filter plates and composite filter plates. The raw materials include complexing agents, organic acids, corrosion inhibitors, compound digestive enzymes, algaecides, and industrial glucose. It can quickly dissolve various blockages such as scale, sludge, and mixed rust on filter plates, offering high cleaning efficiency and effectively preventing corrosion damage to metal equipment, thus extending the service life of the filter plates. However, the use of biological enzymes leads to higher production costs. Chinese invention patent application CN119842446A discloses a ceramic filter plate cleaning agent and its preparation method. The ceramic filter plate cleaning agent is composed of citric acid, aminosulfonic acid, HEDP, EDTA, corrosion inhibitors, AEO-9, JFC, and ultrapure deionized water. It can effectively remove various dirt and impurities from the surface of ceramic filter plates, but the cleaning time is long and the cleaning effect is poor. Summary of the Invention

[0003] In order to develop a liquid cleaning agent with high cleaning efficiency and environmentally friendly and non-corrosive properties, the first aspect of the present invention provides a liquid cleaning agent for micron-sized pores, wherein the liquid cleaning agent has a flux recovery rate of ≥95% at room temperature for 30 minutes in micron-sized pores; the raw materials for preparation include, by weight percentage, 20-30% hydroxy acid detergent, 2-3% corrosion inhibitor, 3-5% chelating agent, 0.1-0.5% surfactant, 1-3% penetrant, and deionized water to make up to 100%.

[0004] This application uses a hydroxy acid detergent, and when combined with a penetrant, the surface tension of the liquid cleaning agent can be reduced to below 22 mN / m, allowing it to quickly penetrate the micron-level micropore channels of the ceramic filter plate, achieving deep cleaning of the micron-level pores. This disrupts the crystal structure of mineral slurry scale and metal oxide scale, transforming insoluble scale into stable water-soluble chelates, preventing secondary deposition and pore blockage of dissolved scale, and achieving full-dimensional cleaning from the surface to the deep micropores.

[0005] As one embodiment, the hydroxy acid detergent includes at least one of gluconic acid, lactic acid, glycolic acid, malic acid, citric acid, tartaric acid, or mandelic acid.

[0006] In one embodiment, the gluconic acid is an aqueous solution of gluconic acid with a mass fraction of 40-60%; the lactic acid is an aqueous solution of lactic acid with a mass fraction of 80-90%.

[0007] In one embodiment, the gluconic acid is an aqueous solution of gluconic acid with a mass fraction of 50%; the lactic acid is an aqueous solution of lactic acid with a mass fraction of 88%.

[0008] In one embodiment, the hydroxy acid detergent comprises an aqueous solution of citric acid and gluconic acid, wherein the mass ratio of the aqueous solution of citric acid and gluconic acid is (10-15):(10-15).

[0009] In one embodiment, the hydroxy acid detergent comprises an aqueous solution of citric acid and gluconic acid, wherein the mass ratio of the aqueous solution of citric acid and gluconic acid is 12:13.

[0010] This application adopts a compound system of citric acid and gluconic acid dihydroxy organic acids. The multihydroxy structure of gluconic acid greatly improves the low-temperature solubility of the system and avoids the low-temperature crystallization and precipitation of single organic acids. At the same time, the step-by-step feeding process of acidic base liquid ensures that all components are completely dissolved and stable in the acidic system, without hydrolysis or complexation precipitation, and achieves stable performance during the ultra-long storage period.

[0011] In one embodiment, the surfactant is a nonionic surfactant or a cationic surfactant. The nonionic surfactant includes at least one of fatty alcohol polyoxyethylene ether, alkylphenol polyoxyethylene ether, polyether, or alkylolamide. The cationic surfactant is a quaternary ammonium salt type cationic surfactant.

[0012] In one embodiment, the fatty alcohol polyoxyethylene ether includes at least isomeric tridecyl alcohol polyoxyethylene ether; and the quaternary ammonium salt cationic surfactant includes at least dicedyldimethylammonium chloride.

[0013] In one embodiment, the penetrant includes at least one of isooctanol polyoxyethylene ether, sodium secondary alkyl sulfonate, or sodium dioctyl sulfosuccinate.

[0014] In one embodiment, the penetrant is isooctanol polyoxyethylene ether.

[0015] In one embodiment, the corrosion inhibitor comprises hexamethylenetetramine (urotropine) and water-soluble imidazoline, wherein the weight ratio of hexamethylenetetramine to water-soluble imidazoline is (1-1.5):(1-1.5).

[0016] In one embodiment, the weight ratio of hexamethylenetetramine to water-soluble imidazoline is 1.25:1.25.

[0017] In one embodiment, the water-soluble imidazoline includes at least one of lauryl imidazoline quaternary ammonium salt and stearyl imidazoline quaternary ammonium salt.

[0018] As one embodiment, the water-soluble imidazoline has an active ingredient content of ≥40% and a degree of quaternization of ≥95%.

[0019] This water-soluble imidazoline can be completely dissolved in the weakly acidic environment of citric acid and gluconic acid without causing stratification or precipitation. At the same time, it can be rapidly adsorbed on the surface of metal and ceramic substrates to form a dense monomolecular protective film. It forms a synergistic corrosion inhibition system with hexamethylenetetramine in the system, which combines anodic passivation and adsorption film formation, and significantly reduces the corrosion rate of acidic systems on 20# carbon steel, 304 stainless steel and alumina ceramics.

[0020] In one embodiment, the chelating agent includes at least one of disodium ethylenediaminetetraacetate, aminotrimethylenephosphonic acid, diethylenetriaminepentamethylenephosphonic acid, hydroxyethylidene diphosphonic acid, or hydroxyethylethylenediaminetriacetic acid.

[0021] In one embodiment, the chelating agent includes disodium ethylenediaminetetraacetate and hydroxyethylidene diphosphonic acid.

[0022] In one embodiment, the hydroxyethylidene diphosphonic acid is an aqueous solution of hydroxyethylidene diphosphonic acid, and the mass concentration of the aqueous solution of hydroxyethylidene diphosphonic acid is 40-60%. Alternatively, the mass concentration of the aqueous solution of hydroxyethylidene diphosphonic acid may be 50%.

[0023] A second aspect of the present invention provides a method for preparing a liquid cleaning agent with micron-sized pores, comprising the following steps: The raw materials for preparing the liquid cleaning agent are pretreated to control the conductivity of deionized water to ≤10μS / cm, and then set aside for later use. Add 80% by mass of deionized water, turn on the stirrer, control the speed at 80-100 rpm, add hydroxy acid detergent at 25-35℃, stir for 15-20 min, control the pH value at 0.5-2, and obtain an acidic base solution. Maintain a rotation speed of 60-80 rpm and a temperature of 25-35°C. Add a chelating agent to the acidic base solution and stir for 10-15 minutes. Then add a corrosion inhibitor and stir for 10-15 minutes to obtain the functional base solution. Maintain a rotation speed of 30-50 rpm and a temperature of 25-35°C. Add surfactant and penetrant to the functional base liquid and stir for 8-10 minutes. Add the remaining deionized water and stir for 3-8 minutes. Let stand to defoam and filter to obtain the liquid cleaning agent.

[0024] As one implementation method, the pretreatment step of the raw materials is as follows: citric acid, disodium ethylenediaminetetraacetate and hexamethylenetetraacetate are pulverized, passed through a 60-mesh sieve, and lumps are removed.

[0025] As one implementation method, the settling and defoaming time is 15-20 minutes.

[0026] In one implementation, the filtration is performed using a 0.3-5μm filter element.

[0027] In one implementation, the filtration is performed using a 0.45μm filter element.

[0028] This invention first prepares an acidic base solution to provide a stable acidic dissolution environment for subsequent chelating agents and corrosion inhibitors, preventing the alkaline components from reacting with organic acids to form precipitation and ensuring system stability. Different rotation speeds are used at different raw material addition stages: high rotation speed ensures rapid dissolution of insoluble solids, while low rotation speed avoids foaming, solving the technical problems of severe foaming and excessive foam in the finished product during existing processes. Finally, a 0.45μm filter element is used to remove trace amounts of insoluble impurities, ensuring the system is free of solid particles and preventing secondary clogging of the micropores of the ceramic filter plate, while significantly improving the product's storage stability.

[0029] A third aspect of the present invention provides an application of a liquid cleaning agent with micron-sized pores for cleaning ceramic filter plates used in mineral processing.

[0030] Compared with the prior art, the present invention has the following beneficial effects: (1) The liquid cleaning agent for micron-sized pores described in this invention uses hydroxy acid cleaning agent combined with penetrant to reduce the surface tension of the liquid cleaning agent to below 22mN / m, quickly penetrate the micron-sized micropore channels of ceramic filter plate, achieve deep cleaning of micron-sized pores, and achieve a flux recovery rate of up to 95% for micron-sized pores at room temperature for 30 minutes.

[0031] (2) The liquid cleaning agent for micron-sized pores described in this invention abandons the strong corrosive inorganic acid system and adopts a mild organic acid composite system, combined with corrosion inhibitors, which can quickly form a dense monomolecular passivation protective film on the surface of ceramic substrates and metal equipment, reduce the corrosion rate, and achieve both efficient descaling and corrosion protection.

[0032] (3) The liquid cleaning agent for micron-sized pores described in this invention adopts a compound system of citric acid and gluconic acid dihydroxy organic acids, which greatly improves the low-temperature solubility of the system and avoids low-temperature crystallization; at the same time, the pre-prepared acidic base liquid can ensure that all components are free from hydrolysis and complexation precipitation in the acidic system, and achieve stable performance during the ultra-long storage period.

[0033] (4) The liquid cleaning agent with micron-sized pores described in this invention does not contain hydrofluoric acid, phosphorus-containing additives, organic solvents and other components. The chemical oxygen demand of post-treatment is low, which greatly reduces the cost of wastewater treatment and the occupational health risks of operators, and is in line with the trend of green industrial development.

[0034] (5) The liquid cleaning agent with micron-sized pores described in this invention can achieve efficient descaling at room temperature without the need for high-temperature heating and activation. It can be adapted to a variety of industrial cleaning processes, greatly reducing the energy consumption, operation and maintenance and environmental protection costs of industrial cleaning, and has extremely strong industrial application value.

[0035] (6) The liquid cleaning agent with micron-sized pores described in this invention achieves a comprehensive breakthrough in meeting the five core requirements of deep and efficient cleaning, zero corrosion protection, long-term storage stability, ultra-low foam compatibility, and full environmental protection compliance, resulting in excellent overall performance. Detailed Implementation

[0036] All raw materials used in the preparation were commercially available.

[0037] Example 1 A liquid cleaning agent with micron-sized pores, the raw materials for preparation include, by weight percentage, 20% hydroxy acid detergent, 2% corrosion inhibitor, 3% chelating agent, 0.1% surfactant, 1% penetrant, and deionized water to make up to 100%.

[0038] The hydroxy acid detergent is an aqueous solution of citric acid and gluconic acid in a mass ratio of 10:10; the gluconic acid aqueous solution has a mass fraction of 50%.

[0039] The surfactant is isotridecyl alcohol polyoxyethylene ether, CAS No.: 69011-36-5.

[0040] The penetrant is isooctanol polyoxyethylene ether JFC-2.

[0041] The corrosion inhibitor is a combination of hexamethylenetetramine and water-soluble imidazoline in a weight ratio of 1:1.

[0042] The water-soluble imidazoline is 1-hydroxyethyl-2-oleoylimidazoline quaternary ammonium salt, CAS No.: 25177-59-7.

[0043] The chelating agent is a combination of disodium ethylenediaminetetraacetate and hydroxyethylidene diphosphonic acid in a weight ratio of 1.5:1.5.

[0044] The hydroxyethylidene diphosphonic acid is an aqueous solution of hydroxyethylidene diphosphonic acid with a mass concentration of 50%.

[0045] A method for preparing a liquid cleaning agent with micron-sized pores includes the following steps: Crush citric acid, disodium ethylenediaminetetraacetate and hexamethylenetetraacetate, pass them through a 60-mesh sieve to remove lumps, and control the conductivity of deionized water to ≤10μS / cm for later use. Add 80% by mass of deionized water, turn on the stirrer, control the speed at 80-100 rpm, add hydroxy acid detergent at 25-35℃, stir for 15-20 min, control the pH value at 0.5-2, and obtain an acidic base solution. Maintain a rotation speed of 60-80 rpm and a temperature of 25-35°C. Add a chelating agent to the acidic base solution and stir for 10-15 minutes. Then add a corrosion inhibitor and stir for 10-15 minutes to obtain the functional base solution. Maintain a rotation speed of 30-50 rpm and a temperature of 25-35°C. Add surfactant and penetrant to the functional base liquid and stir for 8-10 minutes. Add the remaining deionized water and stir for 5 minutes. Let stand to defoam for 15-20 minutes. Filter with a 0.45μm filter to obtain the liquid cleaning agent.

[0046] Example 2 A liquid cleaning agent with micron-sized pores, the raw materials for preparation include, by weight percentage, 25% hydroxy acid detergent, 2.5% corrosion inhibitor, 4% chelating agent, 0.1% surfactant, 1% penetrant, and deionized water to make up to 100%.

[0047] The hydroxy acid detergent is an aqueous solution of citric acid and gluconic acid in a mass ratio of 12:13; the gluconic acid aqueous solution has a mass fraction of 50%.

[0048] The surfactant is isotridecyl alcohol polyoxyethylene ether, CAS No.: 69011-36-5.

[0049] The penetrant is isooctanol polyoxyethylene ether JFC-2.

[0050] The corrosion inhibitor is a combination of hexamethylenetetramine and water-soluble imidazoline in a weight ratio of 1.25:1.25.

[0051] The water-soluble imidazoline is 1-hydroxyethyl-2-oleoylimidazoline quaternary ammonium salt, CAS No.: 25177-59-7.

[0052] The chelating agent is a combination of disodium ethylenediaminetetraacetate and hydroxyethylidene diphosphonic acid in a weight ratio of 2:2.

[0053] The hydroxyethylidene diphosphonic acid is an aqueous solution of hydroxyethylidene diphosphonic acid with a mass concentration of 50%.

[0054] A method for preparing a liquid cleaning agent with micron-sized pores, the specific implementation method is the same as in Example 1.

[0055] Example 3 A liquid cleaning agent with micron-sized pores, the raw materials for preparation include, by weight percentage, 30% hydroxy acid detergent, 3% corrosion inhibitor, 5% chelating agent, 0.1% surfactant, 1% penetrant, and deionized water to make up to 100%.

[0056] The hydroxy acid detergent is an aqueous solution of citric acid and gluconic acid in a mass ratio of 15:15; the gluconic acid aqueous solution has a mass fraction of 50%.

[0057] The surfactant is isotridecyl alcohol polyoxyethylene ether, CAS No.: 69011-36-5.

[0058] The penetrant is isooctanol polyoxyethylene ether JFC-2.

[0059] The corrosion inhibitor is a combination of hexamethylenetetramine and water-soluble imidazoline in a weight ratio of 1.5:1.5.

[0060] The water-soluble imidazoline is 1-hydroxyethyl-2-oleoylimidazoline quaternary ammonium salt, CAS No.: 25177-59-7.

[0061] The chelating agent is a combination of disodium ethylenediaminetetraacetate and hydroxyethylidene diphosphonic acid in a weight ratio of 2.5:2.5.

[0062] The hydroxyethylidene diphosphonic acid is an aqueous solution of hydroxyethylidene diphosphonic acid with a mass concentration of 50%.

[0063] A method for preparing a liquid cleaning agent with micron-sized pores, the specific implementation method is the same as in Example 1.

[0064] Comparative Example 1 A liquid cleaning agent with micron-sized pores and its preparation method are described. The specific implementation method is the same as that in Example 1, except that the raw materials include 30% hydroxy acid detergent, 3% corrosion inhibitor, 5% chelating agent, 0.1% surfactant, and deionized water to 100% by weight percentage.

[0065] Comparative Example 2 A liquid cleaning agent with micron-sized pores and its preparation method are described. The specific implementation method is the same as that in Example 1, except that the raw materials include 30% hydroxy acid detergent, 1% corrosion inhibitor, 5% chelating agent, 0.1% surfactant, 1% penetrant, and deionized water to 100% by weight percentage.

[0066] Comparative Example 3 A liquid cleaning agent with micron-sized pores and its preparation method are described. The specific implementation method is the same as that in Example 1, except that the raw materials include 30% hydroxy acid detergent, 3% corrosion inhibitor, 5% chelating agent, 1% surfactant, 1% penetrant, and deionized water to 100% by weight percentage.

[0067] Comparative Example 4 A liquid cleaning agent with micron-sized pores and its preparation method are described. The specific implementation method is the same as that in Example 1, except that the raw materials include 25% hydroxy acid detergent, 3% corrosion inhibitor, 5% chelating agent, 0.1% surfactant, 1% penetrant, and deionized water to 100% by weight percentage.

[0068] The hydroxy acid detergent is citric acid.

[0069] Comparative Example 5 A commercially available liquid cleaning agent comprises the following ingredients by weight percentage: 15% nitric acid, 10% phosphoric acid, 2% hydroxyethylidene diphosphonic acid, 0.5% fatty alcohol polyoxyethylene ether nonionic surfactant, 0.3% thiourea corrosion inhibitor, and deionized water to 100%.

[0070] Preparation process: At room temperature, add all deionized water to the reactor, start stirring at 60 rpm, add nitric acid and phosphoric acid in sequence, and stir for 10 min until the mixture is uniform; then add hydroxyethylidene diphosphonic acid and thiourea corrosion inhibitor in sequence, and stir for 15 min until completely dissolved; finally add fatty alcohol polyoxyethylene ether nonionic surfactant, and stir for 10 min until completely miscible. After standing, filter through a 0.45 μm filter cartridge and package to obtain the finished product.

[0071] Comparative Example 6 A commercially available liquid cleaning agent for ceramic filter plates, the raw materials by weight percentage are: 12% aminosulfonic acid, 13% phosphoric acid, 2% disodium ethylenediaminetetraacetate, 0.5% penetrant JFC, 0.3% corrosion inhibitor Lan-826, and deionized water to 100%.

[0072] Preparation process: At room temperature, add the full amount of deionized water to the reaction vessel, start stirring at 50 rpm, add aminosulfonic acid and phosphoric acid in sequence, and stir for 15 min until aminosulfonic acid is completely dissolved; then add disodium ethylenediaminetetraacetate and corrosion inhibitor Lan-826 in sequence, and stir for 12 min until completely dissolved; finally add penetrant JFC, and stir for 10 min until completely miscible. After standing and clarifying, filter through a 0.45 μm filter element and package to obtain the finished product.

[0073] Performance testing The ceramic filter plates conforming to GB / T 25994-2010 "Ceramic Filter Plates" were used for testing. The ceramic filter plate samples used were industry-standard No. 3 plates, made of 99% alumina ceramic, with dimensions of Φ30mm×5mm, an average micropore diameter of 2μm, and an initial pure water flux of 100±2 L / (m³). 2 h 0.1MPa).

[0074] Using real ore slurry from an industrial beneficiation plant (iron concentrate slurry, solid content 30%), ceramic filter plate samples were filtered at 0.2 MPa pressure for 2 hours, and then dried in a 60℃ oven for 4 hours to prepare standardized fouled samples with completely clogged micropores. The flux after fouling was uniformly calibrated to be 28±2 L / (m³). 2 h 0.1MPa).

[0075] 1. Descaling performance test: 1) The standardized contaminated samples were placed in the liquid cleaning agents of the examples and comparative examples, respectively, and the industrial standard room temperature immersion + pulse backflushing process was adopted (immersion temperature 25℃, backflushing pressure 0.3MPa, backflushing frequency 5min / time, total cleaning time 30min); after cleaning, the samples were rinsed with deionized water, the pure water flux after cleaning was tested, and the flux recovery rate was calculated according to the following formula.

[0076] Flux recovery rate (%) = (flux after cleaning - flux after fouling) / (initial flux - flux after fouling) × 100%.

[0077] 2) Microscopic verification: After cleaning, SEM was used to observe the unblocking status of the micropore cross-section of the sample to determine whether there was any scale residue or secondary blockage. The test results are shown in Table 1.

[0078] 2. Corrosion test: Refer to GB / T 18175-2012 "Determination of corrosion inhibition performance of water treatment agents by rotating plate method" standard, including alumina ceramic test pieces (50mm×25mm×2mm), 20# carbon steel test pieces, 304 stainless steel test pieces, and nitrile rubber seal test pieces. All test pieces were ground, cleaned and dried to constant weight in advance.

[0079] Each specimen, pretreated to constant weight, was suspended in the liquid cleaning agent of the examples and comparative examples, with the temperature controlled at 25°C and the rotation speed at 75 rpm, and fully immersed for 24 hours. After soaking, remove the test piece, rinse it with deionized water, dry it to constant weight, record the change in mass of the test piece, and calculate the corrosion rate according to the standard formula. Simultaneously, the surface condition of the test pieces was observed, and the changes in surface roughness of the ceramic test piece and the changes in swelling rate of the rubber test piece were tested. The test results are shown in Table 2.

[0080] 3. Storage stability test: Refer to GB / T 35134-2017 "General Technical Conditions for Industrial Cleaning Agents" for stability test methods: 1) Accelerated stability test: After sealing the liquid cleaning agent, place it in a high and low temperature alternating test chamber. Cyclic conditions: -5℃ freezing for 12h → 45℃ high temperature for 12h, which is 1 cycle. A total of 10 cycles are carried out (simulating 12 months of natural storage). 2) Long-term stability test: After sealing the liquid cleaning agent, the samples were placed in environments of -5℃, 25℃, and 45℃ respectively, and stored for 18 months. 3) Regularly observe the appearance of the liquid cleaning agent, including its pH value, stratification, and retention rate of active ingredients. Test results are shown in Table 3.

[0081] 4. Foam performance test: Static foam test: Refer to GB / T 7462-1994 "Determination of foaming power of surfactants - Modified Ross-Miles method" to test the initial foam height and foam height of liquid detergent at 25℃ after 5 minutes.

[0082] Dynamic foam test: Simulating industrial backflushing conditions, the liquid cleaning agent was placed in a sealed container and circulated under a pressure of 0.3 MPa for 10 minutes. The foam height after circulation was recorded to determine whether it would affect industrial use. The test results are shown in Table 4.

[0083] 5. Environmental and Safety Performance Testing: Referring to GB 8978-1996 "Integrated Wastewater Discharge Standard" and GB / T 26396-2011 "Safety Technical Specifications for Detergent Products," the total phosphorus, fluoride, and COD values ​​in the liquid detergent wastewater, as well as the product's biodegradability rate, were tested. The test results are shown in Table 5.

[0084] Table 1

[0085] The liquid cleaning agent of this invention, with a preferred mixing ratio range, achieves a flux recovery rate of ≥95% after 30 minutes of cleaning at room temperature, with the optimal embodiment reaching ≥99%, far exceeding that of commercially available control products (≤71%) and existing patent control products (≤55%). Furthermore, SEM verification confirms complete unclogging of deep micropores without secondary blockage, thoroughly solving the core industry pain point that existing technologies cannot remove deep micropore scale buildup.

[0086] A comparison of Example 2 and Comparative Example 1 revealed that the penetrant can reduce the surface tension of the system, allowing the active ingredients to quickly penetrate into the micron-sized pores. Without this component, the pickling agent cannot reach the deep layers of the micropores and can only remove surface scale, failing to address the industry's core problem of deep scale blockage, resulting in a significant decrease in cleaning efficiency.

[0087] Table 2

[0088] Note: Industrial equipment protection requires a corrosion rate ≤0.01mm / a to indicate no significant corrosion. The sample of this invention far exceeds the national standard requirements.

[0089] The corrosion rate of the sample of this invention on ceramics and metals is ≤0.003mm / a, which is only 1 / 30 to 1 / 50 of that of commercially available reference products. At the same time, it has no swelling or aging effect on rubber seals, thus solving the core contradiction that efficient descaling in existing technologies is inevitably accompanied by severe corrosion.

[0090] A comparison of Example 2 and Comparative Example 2 revealed that when the amount of corrosion inhibitor added was lower than the preferred lower limit, a complete and dense protective film could not be formed on the substrate surface. The pickling agent directly corroded the metal equipment and rubber seals, and the corrosion rate soared to more than 30 times that of Example 2, which seriously affected the service life of the equipment and posed a safety hazard.

[0091] Table 3

[0092] The liquid samples of this invention showed no deterioration after 12 months of storage, with an effective ingredient retention rate of ≥99%, which is far superior to the defects of commercially available products that show obvious deterioration after 6 months, and solves the pain point of poor storage stability of existing products.

[0093] Compared with Comparative Example 4, Example 2 showed that the solubility of the single citric acid system decreased significantly at low temperatures, making it prone to crystallization and precipitation, resulting in extremely poor product storage stability. At the same time, the lack of the polyhydroxy chelating effect of gluconic acid reduced the solubility of metal ions such as iron and aluminum, significantly reducing cleaning efficiency and failing to meet the storage and usage needs of different regions.

[0094] Table 4

[0095] The liquid cleaning agent of this invention has a static and dynamic foam height of ≤5mm, which belongs to the ultra-low foaming system. No additional defoamer needs to be added. It is fully compatible with the backwashing cleaning process of industrial ceramic filter plates and solves the industry pain point of serious foaming of existing products.

[0096] A comparison of Example 2 and Comparative Example 3 revealed that when the amount of surfactant added was too high, the system produced a large amount of stable foam, which was completely unsuitable for the pulse backwash cleaning process of ceramic filter plates. This would lead to insufficient backwash pressure, overflow of cleaning fluid, and cavitation damage to the pump body, thus failing to meet the requirements for industrial use.

[0097] Table 5

[0098] Note: National Integrated Wastewater Discharge Standard Level I Limits: Total Phosphorus ≤ 0.5 mg / L, Fluoride ≤ 10 mg / L, COD ≤ 100 mg / L.

[0099] The product of this invention is phosphorus-free, fluorine-free, low COD, and biodegradable, fully compliant with national environmental protection standards, avoiding the environmental compliance risks of existing hydrofluoric acid and phosphorus-containing systems, and conforming to the trend of green industrial development.

Claims

1. A liquid cleaning agent with micron-sized pores, characterized in that, The liquid cleaning agent has a flux recovery rate of ≥95% at room temperature for 30 minutes in micron-sized pores; the raw materials for preparation include, by weight percentage, 20-30% hydroxy acid detergent, 2-3% corrosion inhibitor, 3-5% chelating agent, 0.1-0.5% surfactant, 1-3% penetrant, and deionized water to 100%.

2. The liquid cleaning agent with micron-sized pores according to claim 1, characterized in that, The hydroxy acid detergent includes at least one of gluconic acid, lactic acid, glycolic acid, malic acid, citric acid, tartaric acid, or mandelic acid.

3. The liquid cleaning agent for micron-sized pores according to claim 2, characterized in that, The gluconic acid is an aqueous solution of gluconic acid with a mass fraction of 40-60%; the lactic acid is an aqueous solution of lactic acid with a mass fraction of 80-90%.

4. The liquid cleaning agent for micron-sized pores according to claim 3, characterized in that, The hydroxy acid detergent comprises an aqueous solution of citric acid and gluconic acid, wherein the mass ratio of the aqueous solution of citric acid and gluconic acid is (10-15):(10-15).

5. The liquid cleaning agent for micron-sized pores according to claim 1, characterized in that, The surfactant is a nonionic surfactant or a cationic surfactant. The nonionic surfactant includes at least one of fatty alcohol polyoxyethylene ether, alkylphenol polyoxyethylene ether, polyether, or alkylolamide. The cationic surfactant is a quaternary ammonium salt type cationic surfactant.

6. The liquid cleaning agent with micron-sized pores according to claim 1, characterized in that, The penetrant includes at least one of isooctanol polyoxyethylene ether, sodium secondary alkyl sulfonate, or sodium dioctyl sulfosuccinate.

7. The liquid cleaning agent for micron-sized pores according to claim 2, characterized in that, The corrosion inhibitor comprises hexamethylenetetramine and water-soluble imidazoline, wherein the weight ratio of hexamethylenetetramine to water-soluble imidazoline is (1-1.5):(1-1.5).

8. The liquid cleaning agent for micron-sized pores according to claim 7, characterized in that, The chelating agent includes at least one of disodium ethylenediaminetetraacetate, aminotrimethylenephosphonic acid, diethylenetriaminepentamethylenephosphonic acid, or hydroxyethylethylenediaminetriacetic acid.

9. A method for preparing a liquid cleaning agent with micron-sized pores according to claim 8, characterized in that, Includes the following steps: The raw materials for preparing the liquid cleaning agent are pretreated to control the conductivity of deionized water to ≤10μS / cm, and then set aside for later use. Add 80% by mass of deionized water, turn on the stirrer, control the speed at 80-100 rpm, add hydroxy acid detergent at 25-35℃, stir for 15-20 min, control the pH value at 0.5-2, and obtain an acidic base solution. Maintain a rotation speed of 60-80 rpm and a temperature of 25-35°C. Add a chelating agent to the acidic base solution and stir for 10-15 minutes. Then add a corrosion inhibitor and stir for 10-15 minutes to obtain the functional base solution. Maintain a rotation speed of 30-50 rpm and a temperature of 25-35°C. Add surfactant and penetrant to the functional base liquid and stir for 8-10 minutes. Add the remaining deionized water and stir for 3-8 minutes. Let stand to defoam and filter to obtain the liquid cleaning agent.

10. The application of a liquid cleaning agent with micron-sized pores according to any one of claims 1-8, characterized in that, It is used in the cleaning of ceramic filter plates for mineral processing.

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