A stable industrialized mass-produced hypochlorous acid solution, a preparation method and application thereof

Abstract

The application provides an industrial mass production stable hypochlorous acid solution and a preparation method and application thereof, and belongs to the technical field of industrial production of disinfectants, and comprises the following steps: putting industrial-grade sodium chloride, sodium citrate and phosphate into a batching container, adding deionized water to stir and dissolve, using a pH regulator to pre-adjust the initial pH of the solution, and obtaining an electrolysis precursor solution; conveying the electrolysis precursor solution to a diaphragmless electrolytic cell to perform electrolysis, forming an electrolyte containing available chlorine, and discharging when the available chlorine content reaches a target value; transferring the electrolyte into a maturation storage tank, finely adjusting the pH to 5.0-6.5, and standing for maturation, so that the stable hypochlorous acid solution is obtained. The industrial mass production method provided by the application has moderate equipment investment, easily available raw materials, stable process, and easy treatment of three wastes, and can continuously produce a large amount of 2000ppm-grade hypochlorous acid stock solution with high stability and high activity and its sterilization preparation, and is widely applied to the fields of medical treatment, food, public health, agriculture and daily disinfection.

Description

Technical Field

[0001] This invention belongs to the field of industrial production technology of disinfectants and bactericides, and particularly relates to a stable hypochlorous acid solution for industrial mass production, its preparation method and application. Background Technology

[0002] Hypochlorous acid (HOCl), a strong oxidizing disinfectant, has been widely used in medical disinfection, food processing, public health and epidemic prevention, agricultural disease control, and daily household cleaning due to its broad-spectrum bactericidal ability, residue-free properties, excellent safety, and environmental friendliness. Compared to traditional chlorine-containing disinfectants (such as sodium hypochlorite), hypochlorous acid exists primarily in molecular form under neutral to weakly acidic conditions, and its bactericidal activity is primarily driven by hypochlorite ions (ClO₂). - It is dozens to hundreds of times more potent than other disinfectants and has extremely low irritation to the skin and mucous membranes, earning it the reputation of an "ideal green disinfectant".

[0003] Hypochlorous acid disinfectant boasts advantages such as safety, environmental friendliness, and broad-spectrum bactericidal activity, making it suitable for a wide range of applications. However, existing industrial-scale production of high-concentration hypochlorous acid involves high investment and operating costs. Conventional formulation processes rely on concentrated hydrochloric acid, resulting in poor safety and insufficient product stability during mass production; high-concentration products experience significant degradation of available chlorine after only 1-2 months of storage. Existing laboratory formulations are only suitable for small-scale trials and cannot achieve continuous industrial-scale production. Raw material input, electrolysis parameters, and post-processing are difficult to adapt to assembly line production, hindering the industrialization of high-concentration, stable hypochlorous acid products. Therefore, there is an urgent need to upgrade laboratory formulations to industrial-scale processes to achieve low-cost, continuous mass production of highly stable hypochlorous acid. Summary of the Invention

[0004] In view of this, the purpose of this invention is to provide a method for industrial mass production of stable hypochlorous acid solution. This invention adopts industrial continuous batching, a sodium citrate and phosphate composite stabilization system, and a modular diaphragm-free circulating electrolysis production line. It does not require concentrated hydrochloric acid and can produce highly active hypochlorous acid stock solution with available chlorine of 2000±200ppm, pH 5.0~6.5, and hypochlorous acid molecule content ≥90%.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a method for industrial-scale production of a stable hypochlorous acid solution, comprising the following steps: 1) Ingredients: Add industrial grade sodium chloride, sodium citrate and phosphate into the mixing container, add deionized water and stir to dissolve, use pH adjuster to pre-adjust the initial pH of the solution to obtain the electrolysis precursor solution; 2) Electrolysis: The electrolysis precursor solution obtained in step 1) is transported to a diaphragmless electrolytic cell for electrolysis. Electrolysis forms an electrolyte containing available chlorine. The electrolyte is discharged after the available chlorine content reaches the target value. 3) Maturation and preparation: Transfer the electrolyte obtained in step (2) into a maturation tank, finely adjust the pH to 5.0-6.5, and let it stand to mature, thus obtaining a stable hypochlorous acid solution.

[0006] Preferably, the mass ratio of sodium citrate to phosphate is 1:0.5 to 2.

[0007] Preferably, the phosphate is selected from one or more of sodium phosphate, disodium hydrogen phosphate, sodium dihydrogen phosphate, potassium phosphate, dipotassium hydrogen phosphate, and potassium dihydrogen phosphate.

[0008] Preferably, the pH adjuster is selected from one or more of citric acid, acetic acid, and food-grade phosphate.

[0009] Preferably, the mixing container is a 316L stainless steel mixing tank equipped with stirring and online pH monitoring.

[0010] Preferably, the diaphragmless electrolyzer is a multi-group parallel industrial titanium electrode diaphragmless electrolyzer.

[0011] Preferably, the electrolysis method includes: using closed-loop cyclic electrolysis, with a single cell voltage of 10-12V, a current of 1.2-2.0A, and batch cyclic electrolysis for 15-60 minutes.

[0012] Preferably, the target value is an available chlorine content of 2000±200ppm.

[0013] The present invention also provides a hypochlorous acid solution prepared by the above-mentioned method for industrial mass production of a stable hypochlorous acid solution.

[0014] The present invention also provides the application of the above-mentioned hypochlorous acid solution in the preparation of bactericidal agents.

[0015] Beneficial effects of this invention: 1. This invention addresses the problems of existing laboratory formulas being unable to be mass-produced, high cost of traditional industrial equipment, poor product stability, dependence on concentrated hydrochloric acid, and rapid decay of available chlorine. It adopts industrial continuous batching, a sodium citrate and phosphate composite stabilization system, and a modular diaphragm-free circulating electrolysis production line, which eliminates the need for concentrated hydrochloric acid and can produce highly active hypochlorous acid stock solution with available chlorine of 2000±200ppm, pH 5.0~6.5, and a hypochlorous acid molecule content of ≥90%. 2. The hypochlorous acid solution prepared by the method of the present invention has an effective chlorine decay rate of ≤10% after being stored at room temperature and protected from light for 6 months, and meets the 12-month shelf life requirement of the disinfection technical specifications after accelerated testing at 54℃. 3. The hypochlorous acid stock solution prepared by this invention, diluted to 100 ppm and reacted for 2-5 minutes, exhibits a bactericidal and fungal kill rate ≥99.999%. 4. The production process of this invention is continuous and controllable, the waste is easy to treat, the raw materials are readily available, and the mass production repeatability is excellent. It is applicable to the fields of skin and mucous membranes, food contact surfaces, air, drinking water, medical devices, and environmental disinfection. Detailed Implementation

[0016] This invention provides a method for industrial-scale production of a stable hypochlorous acid solution, comprising the following steps: 1) Ingredients: Add industrial grade sodium chloride, sodium citrate and phosphate into the mixing container, add deionized water and stir to dissolve, use pH adjuster to pre-adjust the initial pH of the solution to obtain the electrolysis precursor solution; 2) Electrolysis: The electrolysis precursor solution obtained in step 1) is transported to a diaphragmless electrolytic cell for electrolysis. Electrolysis forms an electrolyte containing available chlorine. The electrolyte is discharged after the available chlorine content reaches the target value. 3) Maturation and preparation: Transfer the electrolyte obtained in step (2) into a maturation tank, finely adjust the pH to 5.0-6.5, and let it stand to mature, thus obtaining a stable hypochlorous acid solution.

[0017] The present invention does not have any special limitation on the source of the industrial-grade sodium chloride, sodium citrate, and phosphate; conventional commercially available products in the field can be used.

[0018] In this invention, the mass concentration of sodium chloride in the electrolytic precursor solution is preferably 0.5% to 5%.

[0019] In this invention, the preferred mass ratio of sodium citrate to phosphate is 1:0.5 to 2.

[0020] In this invention, the phosphate is selected from one or more of sodium phosphate, disodium hydrogen phosphate, sodium dihydrogen phosphate, potassium phosphate, dipotassium hydrogen phosphate, and potassium dihydrogen phosphate.

[0021] In this invention, the pH adjuster is selected from one or more of citric acid, acetic acid, and food-grade phosphate.

[0022] In this invention, the mixing container is preferably a 316L stainless steel mixing tank equipped with stirring and online pH monitoring.

[0023] In this invention, the stirring is preferably carried out at room temperature, and the stirring time is preferably 20 to 30 minutes.

[0024] In this invention, the diaphragmless electrolytic cell is preferably a diaphragmless electrolytic cell with multiple sets of parallel industrial titanium electrodes.

[0025] In this invention, the preferred method of electrolysis includes: closed-loop cyclic electrolysis, electrode spacing of 1.5-2 cm, single-cell voltage of 10-12 V, current of 1.2-2.0 A, and batch cyclic electrolysis for 15-60 min.

[0026] In this invention, the curing process is preferably carried out in a sealed curing tank at room temperature with static curing.

[0027] In this invention, the electrolysis section is preferably equipped with a tail gas alkaline spray absorption device, and the trace amounts of chlorine-containing tail gas are discharged after being treated to render them harmless.

[0028] In this invention, the effective chlorine concentration of the hypochlorous acid solution is preferably 2000±200ppm, the pH is preferably 5.0~6.5, and the proportion of hypochlorous acid molecules is ≥90%.

[0029] The present invention also provides a hypochlorous acid solution prepared by the above-mentioned method for industrial mass production of a stable hypochlorous acid solution.

[0030] In this invention, the hypochlorous acid solution is stored at room temperature and protected from light for 6 months, and the overall decay rate of available chlorine is ≤10%.

[0031] In this invention, the hypochlorous acid disinfectant is a green and environmentally friendly disinfectant that is non-corrosive, safe, colorless, odorless, residue-free, and biodegradable.

[0032] The present invention also provides the application of the above-mentioned hypochlorous acid solution in the preparation of bactericidal agents.

[0033] The hypochlorous acid solution described in this invention can be applied to the disinfection of skin and mucous membranes, food contact surfaces, air, drinking water, medical devices, and the environment.

[0034] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0035] Example 1 Industrialized mass production of 1000L batches 1000L of industrial deionized water (resistivity ≥ 1 MΩ·cm) 25kg of industrially refined sodium chloride Composite stabilizer (industrial grade): sodium citrate 0.8 kg, sodium dihydrogen phosphate 0.5 kg; pH adjuster: Adjust the pH to 5.4 with citric acid, and mix thoroughly in a sealed mixing tank.

[0036] The feed solution was fed into a parallel titanium electrode electrolytic cell with an electrode spacing of 2 cm, a voltage of 11 V, a single cell current of 1.6 A, and circulated electrolysis for 12 min. After discharge, the pH was adjusted to 5.4 by ripening. The measured available chlorine was 1984.5 ppm. The tail gas was completely absorbed by dilute alkali spraying, and there was no chlorine leakage.

[0037] Example 2 Industrialized mass production of 1000L batches 1000L of industrial deionized water 24 kg of sodium chloride Composite stabilizer (industrial grade): sodium citrate 0.95 kg, sodium dihydrogen phosphate 0.6 kg; pH adjuster: Adjust the pH to 5.6 with citric acid, and mix thoroughly in a sealed mixing tank.

[0038] Electrolysis was carried out in a diaphragmless electrolytic cell with a titanium electrode spacing of 2 cm, a voltage of 11 V, a current of 1.5 A, and an electrolysis time of 15 min. After discharge, the material was aged and the pH was adjusted to 5.6. The measured available chlorine content was 1899.25 ppm.

[0039] Example 3 Industrialized mass production of 1000L batches 1000L of industrial deionized water 23kg of sodium chloride Composite stabilizer (industrial grade): sodium citrate 1.1 kg, sodium dihydrogen phosphate 0.75 kg; pH adjuster: Adjust the pH to 5.6 with citric acid, and mix thoroughly in a sealed mixing tank; The titanium electrode spacing was 1.5 cm, the voltage was 12 V, the current was 2.2 A, and the electrolysis time was 16 min. After discharge, the pH was adjusted to 5.6 and the available chlorine was 2120 ppm.

[0040] Example 4 Performance testing Test 1: Stability Three batches of hypochlorous acid disinfectant prepared in Examples 1-3 were placed in a constant temperature stabilization chamber at 54±2℃ and 65%±5%RH for 0 days and 14 days, respectively. The changes in their content and pH value were measured, and the results are shown in Table 1. The results showed that under accelerated test conditions, the properties of the hypochlorous acid solution remained unchanged and the content was stable. At the same time, the hypochlorous acid solution system prepared by this invention was stable, maintained within the qualified range for a long time, and decreased slowly. Moreover, users can directly dilute it to a suitable concentration during the disinfection process before use.

[0041] Table 1. Stability of hypochlorous acid solution

[0042] As shown in Table 1, the hypochlorous acid aqueous solutions prepared in Examples 1-3 have a pH between 5 and 6.5, making them weakly acidic hypochlorous acid aqueous solutions, with an effective chlorine content between 1800 and 2200 ppm. After aging at 54°C for 14 days, the effective chlorine content is only 1.34%-5.42%, demonstrating good stability and a shelf life of up to 12 months (the "Disinfection Technical Specifications" stipulate that if the decomposition rate is <10% after 14 days of storage at 54°C, the shelf life can be set at 1 year).

[0043] Example 5 sterilization effect To verify the bactericidal effect of the hypochlorous acid solution prepared according to this invention, the slightly acidic hypochlorous acid obtained in Examples 1-3 of this invention was tested for its bactericidal effect. Test method: The test was conducted according to the test methods in GB / T38502-2020 (5.6.3 and 5.8.2) of "Laboratory Test Methods for Bactericidal Effect of Disinfectants". The results are shown in Table 2: Table 2. Bactericidal effect of hypochlorous acid solution on test strains

[0044] Test results: The test samples showed a kill rate of >5.00 against Escherichia coli and Staphylococcus aureus in the suspension after 5 min of contact; and a kill rate of >4.00 against Candida albicans in the suspension after 5 min of contact.

[0045] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for industrial-scale mass production of a stable hypochlorous acid solution, characterized in that, Includes the following steps: 1) Ingredients: Add industrial grade sodium chloride, sodium citrate and phosphate into the mixing container, add deionized water and stir to dissolve, use pH adjuster to pre-adjust the initial pH of the solution to obtain the electrolysis precursor solution; 2) Electrolysis: The electrolysis precursor solution obtained in step 1) is transported to a diaphragmless electrolytic cell for electrolysis. Electrolysis forms an electrolyte containing available chlorine. The electrolyte is discharged after the available chlorine content reaches the target value. 3) Maturation and preparation: Transfer the electrolyte obtained in step (2) into a maturation tank, finely adjust the pH to 5.0-6.5, and let it stand to mature, thus obtaining a stable hypochlorous acid solution.

2. The method for industrial-scale mass production of a stable hypochlorous acid solution according to claim 1, characterized in that, In step 1), the mass ratio of sodium citrate to phosphate is 1:0.5-2.

3. The method for industrial-scale mass production of a stable hypochlorous acid solution according to claim 1, characterized in that, The phosphate is selected from one or more of sodium phosphate, disodium hydrogen phosphate, sodium dihydrogen phosphate, potassium phosphate, dipotassium hydrogen phosphate, and potassium dihydrogen phosphate.

4. The method for industrial-scale mass production of a stable hypochlorous acid solution according to claim 1, characterized in that, In step 1), the pH adjuster is selected from one or more of citric acid, acetic acid, and food-grade phosphate.

5. The method for industrial-scale mass production of a stable hypochlorous acid solution according to claim 1, characterized in that, The mixing container in step 1) is a 316L stainless steel mixing tank equipped with stirring and online pH monitoring.

6. The method for industrial-scale mass production of a stable hypochlorous acid solution according to claim 1, characterized in that, In step 2), the diaphragmless electrolytic cell is a multi-group parallel industrial titanium electrode diaphragmless electrolytic cell.

7. The method for industrial-scale mass production of a stable hypochlorous acid solution according to claim 1, characterized in that, The electrolysis method in step 2) includes: using closed-loop cyclic electrolysis, with a single cell voltage of 10-12V, a current of 1.2-2.0A, and batch cyclic electrolysis for 15-60 minutes.

8. The method for industrial-scale mass production of a stable hypochlorous acid solution according to claim 1, characterized in that, The target value in step 2) is an available chlorine content of 2000±200ppm.

9. The hypochlorous acid solution prepared by the method for industrial mass production of a stable hypochlorous acid solution according to any one of claims 1 to 8.

10. The use of the hypochlorous acid solution according to claim 9 in the preparation of bactericidal agents.

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