Detergent for actinide nuclide pollution and preparation method thereof

Abstract

The invention relates to a decontaminant for pollution of actinide nuclides and a preparation method thereof, and the decontaminant for pollution of actinide nuclides comprises the following raw materials: 4-10% of a surfactant; 2-5% of a chelating agent; 3-7% of an auxiliary agent; and the balance of water. The detergent disclosed by the invention is simple in preparation method and stable in physicochemical property, can realize a good decontamination effect only by conventional cleaning, is non-toxic, non-irritant, non-corrosive, green and safe, and can be suitable for decontamination of radioactive contamination at positions such as equipment surfaces, grounds, tools, personnel body surfaces and the like in nuclear material production and processing and spent fuel post-treatment.

Description

Technical Field

[0001] The invention belongs to the technical field of radioactive pollution decontamination, and specifically relates to a decontaminant for actinide nuclide contamination and a preparation method thereof. Background Art

[0002] Radioactive contamination often occurs during the operation, maintenance and decommissioning of nuclear facilities. Carrying out the decontamination of these radioactive nuclides is an important means to ensure the safe operation of nuclear facilities, prevent the spread of radioactive contamination, and protect the safety of workers and the environment. Uranium compounds, together with other actinides such as plutonium or americium, constitute the main components of nuclear fuel and nuclear waste. Compared with other nuclides, actinides are more toxic and radiate (especially alpha emitters inhaled into the human body). In the process of nuclear material production and processing and spent fuel reprocessing, equipment surfaces, ground, tools, body surfaces and other locations are often contaminated by radioactivity. Therefore, it is extremely important to carry out decontamination work on equipment surfaces, ground, tools, body surfaces and other locations.

[0003] The currently disclosed decontaminants for radionuclide contamination are as follows: 1) Strong acids, such as sulfuric acid, nitric acid, and hydrochloric acid, etc. Although they have good decontamination effects, they are highly corrosive and can easily damage equipment, and cannot be used for body surface decontamination; 2) Ordinary decontaminants are compounded with surfactants to remove radionuclide contamination. Although their formula is mild and causes little damage to equipment, their decontamination effect is very poor when used for wiping, and they need to be combined with ultrasonic decontamination, which produces a large amount of secondary waste liquid, which limits most application scenarios and has great application limitations; 3) DTPA and EDTA are used in combination to remove plutonium and trans-plutonium radionuclide contamination. The problems they have are poor decontamination effects and irritation to the skin. They can only be used for body surface decontamination in emergency scenarios and cannot be used for radionuclide decontamination under daily circumstances.

[0004] Therefore, it is very important to develop a decontamination agent for actinide nuclide contamination that has good decontamination effect, is harmless to equipment and has no irritation to the skin, and a preparation method thereof. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects in the prior art and provide a decontamination agent for actinide nuclide contamination and a preparation method thereof, which has good decontamination effect, does not damage equipment, and does not irritate the skin. It can be used for decontamination of actinide nuclides on equipment surfaces, floors, tools, and human body surfaces.

[0006] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0007] A decontaminant for actinide nuclide contamination, comprising the following raw materials in percentage:

[0008] Surfactant: 4-10%;

[0009] Chelating agents: 2-5%;

[0010] Additives: 3-7%;

[0011] Water: Balance.

[0012] As a further technical solution, the surfactant is selected from one or more of ethanolamine, sodium dodecyl diphenyl ether disulfonate, sodium fatty alcohol polyoxyethylene ether sulfate, sodium fatty alcohol polyoxyethylene ether carboxylate, alkyl glucoside, sodium α-olefin sulfonate, fatty acid methyl ester ethoxylate, fatty alcohol polyoxyethylene ether, and polyoxyethylene mono-tert-octylphenyl ether.

[0013] As a further technical solution, the chelating agent is selected from one or more of phenolic crown ethers, hydroxypyridones, o-phenols, carboxylic acids, phosphonic acids, ethylenediaminetetraacetic acid, tetrasodium glutamate diacetate, methylglycine diacetic acid, and tetrasodium iminodisuccinate.

[0014] As a further technical solution, the auxiliary agent is selected from one or more of glycerol, citric acid, tea polyphenols, vitamin E, 1-methoxy-2-propanol, benzethonium chloride, modified oil ethoxylate, and dodecyl dimethyl betaine.

[0015] As a further technical solution, the decontaminant for actinide nuclide contamination is used to remove actinide nuclides from any one of the surfaces of equipment, ground, tools, and human bodies.

[0016] As a further technical solution, the actinide nuclides include one or more of uranium-238, plutonium-242, and thorium-232.

[0017] As a further technical solution, step 1, after weighing the raw materials in proportion, add the chelating agent into water, heat and dissolve, to obtain a chelating agent solution;

[0018] Step 2, adding a surfactant to the chelating agent solution of step 1, heating and dissolving, to obtain a composite solution;

[0019] Step 3: adding the auxiliary agent to the compound solution described in step 2 to obtain a decontaminant for actinide nuclide contamination.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] The chelating agent and the surfactant of the present invention are used in combination, and the auxiliary agent is used to perform radionuclide decontamination, wherein the auxiliary agent can improve the permeability of the product on the one hand, thereby improving the decontamination ability of the product, and can also play a role in radiation protection on the other hand. In addition, the addition of the auxiliary agent can also improve the stability of the formula, can reduce the amount of the chelating agent, and further improve the biosafety of the product. The preparation method of the radionuclide decontaminant of the present invention is simple, and the physicochemical properties are stable. It only needs conventional cleaning to achieve a good decontamination effect, and it is non-toxic, non-irritating, non-corrosive, green and safe, and can be applied to the radioactive decontamination of equipment surfaces, ground, tools, personnel surfaces and the like in nuclear material production and processing and spent fuel post-processing. DETAILED DESCRIPTION

[0022] The technical solution of the present invention is described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] Example 1

[0024] A decontaminant for actinide nuclide contamination, comprising the following raw materials in percentage by weight:

[0025]

[0026] The preparation method thereof comprises the following steps:

[0027] Step 1, weighing each raw material in proportion, adding the chelating agent into water, heating and dissolving, and obtaining a chelating agent solution;

[0028] Step 2, adding a surfactant to the chelating agent solution of step 1, heating and dissolving, to obtain a composite solution;

[0029] Step 3: adding the auxiliary agent to the compound solution described in step 2, fixing the volume, and obtaining a decontaminant for actinide nuclide contamination.

[0030] Example 2

[0031] A decontaminant for actinide nuclide contamination, comprising the following raw materials in percentage by weight:

[0032]

[0033] The preparation method is the same as that in Example 1.

[0034] Comparative Example 1

[0035] A decontaminant for actinide nuclide contamination, comprising the following raw materials in percentage by weight: the same as Example 1, except that the auxiliary agents dodecyl dimethyl betaine, citric acid and benzethonium chloride are removed;

[0036] The preparation method thereof comprises the following steps:

[0037] Step 1, weighing each raw material in proportion, adding the chelating agent into water, heating and dissolving, and obtaining a chelating agent solution;

[0038] Step 2: Add the surfactant to the chelating agent solution of step 1, heat to dissolve, and adjust the volume to obtain a detergent for actinide nuclide contamination.

[0039] Comparative Example 2

[0040] A decontaminant for actinide nuclide contamination, comprising the following raw materials in percentage by weight:

[0041]

[0042] Same as Example 2, except that the auxiliary agents glycerol, dodecyl dimethyl betaine, and modified oil ethoxylate are removed, but the contents of chelating agents methyl glycine diacetic acid and ethylenediamine tetraacetic acid are increased;

[0043] The preparation method thereof comprises the following steps: same as comparative example 1.

[0044] Effect example 1: Nuclide decontamination effect on stainless steel products

[0045] Preparation simulation 238 U contaminated stainless steel sample (method see: RL Demmer. Development of Simulated Contamination (SIMCON) and Miscellaneous Decontamination Scoping Tests, Westinghouse Idaho Nuclear Company, Inc., 1994.), wipe the contaminated surface about 30 times with absorbent cotton or cotton cloth soaked in detergent. After each wipe, change the wiping direction appropriately, and use different parts of the absorbent cotton or cotton cloth each time, and then let it stand to dry.

[0046] The residual level of contaminated sample surface was measured by surface contamination meter and the decontamination rate was calculated. The results are shown in Table 1.

[0047]

[0048] C1: Radioactivity before decontamination (unit: Bq / cm 2 )

[0049] C2: Radioactivity after decontamination (unit: Bq / cm 2 )

[0050] Table 1

[0051] Decontamination rate% Example 1 91.95 Comparative Example 1 73.52

[0052] From the data in Table 1, it can be seen that when removing radionuclide contamination on the surface of stainless steel, the decontamination rate of Example 1 in which an additive is added can reach 91.95%, which is 18.43% higher than that of Comparative Example 1 in which no additive is added.

[0053] In summary, the decontaminant of the present invention has a significant effect on removing radioactive pollutants on the surface of stainless steel in nuclear facilities.

[0054] Effect Example 2: Radionuclide decontamination effect and biosafety on the body surface

[0055] 1. Body surface decontamination effect:

[0056] 3cm*3cm cleaned and dried pigskin was measured with LB 124SCINT surface contamination measuring instrument. The pigskin was fixed on the positioner and about 0.1ml 11490.00Bq / l was dripped into the center of the visible sample surface. 238 U in water solution to make the contaminated liquid evenly distributed on the surface of the sample. Place the positioner horizontally in a fume hood and dry it in an environment with a temperature of (10-30)°C and a relative humidity of 40%. The drying time is 0.5 hours, 6 hours, and 12 hours respectively. Remove the sample from the positioner, absorb the remaining water with filter paper, measure the radioactivity of the contaminated surface with a surface contamination meter and deduct the background to calculate C1. Wipe the contaminated surface with absorbent cotton or cotton cloth soaked in detergent for about 30 times. After each wiping, change the wiping direction appropriately, and use different parts of the absorbent cotton or cotton cloth each time, and then let it stand to dry. Use a surface contamination meter to measure the residual level on the pig skin surface after disinfection and deduct the background, calculate C2, and calculate the decontamination rate. The calculation method is the same as in Example 1. The results are shown in Table 2.

[0057] 2. Biosafety:

[0058] Skin irritation was tested according to the experimental method of GB / T16886.10-2017 "Biological Evaluation of Medical Devices Part 10: Irritation and Skin Sensitization Test".

[0059] Table 2

[0060]

[0061] From the data in Table 2, it can be seen that after adding an auxiliary agent and reducing the chelating agent content, the decontamination effect of the present invention is basically the same as or slightly better than that of Comparative Example 2; however, in the biosafety test, the present invention is only at a very mild level, while Comparative Example 2 is mild. Compared with Comparative Example 2 in which no auxiliary agent is added but the chelating agent content is increased, the skin irritation of the present invention is significantly reduced.

[0062] In summary, the addition of the adjuvant of the present invention helps to reduce the dosage of the chelating agent and further improve biosafety.

[0063] The above-described embodiments are only preferred embodiments of the present invention, and are not exhaustive of the feasible implementations of the present invention. For those skilled in the art, any obvious changes made thereto without departing from the principles and spirit of the present invention should be considered to be included in the scope of protection of the claims of the present invention.

Claims

1. A decontaminant for actinide nuclide contamination, characterized in that: Including the following percentages of raw materials: Surfactant: 4-10%; Chelating agents: 2-5%; Additives: 3-7%; Water: Balance.

2. The decontaminant for actinide nuclide contamination according to claim 1, characterized in that: The surfactant is selected from one or more of ethanolamine, sodium dodecyl diphenyl ether disulfonate, sodium fatty alcohol polyoxyethylene ether sulfate, sodium fatty alcohol polyoxyethylene ether carboxylate, alkyl glucoside, sodium α-olefin sulfonate, fatty acid methyl ester ethoxylate, fatty alcohol polyoxyethylene ether, and polyoxyethylene mono-tert-octylphenyl ether.

3. The decontaminant for actinide nuclide contamination according to claim 1, characterized in that: The chelating agent is selected from one or more of phenolic crown ethers, hydroxypyridones, o-phenols, carboxylic acids, phosphonic acids, ethylenediaminetetraacetic acid, tetrasodium glutamate diacetate, methylglycine diacetic acid, and tetrasodium iminodisuccinate.

4. The decontaminant for actinide nuclide contamination according to claim 1, characterized in that: The auxiliary agent is selected from one or more of glycerol, citric acid, tea polyphenols, vitamin E, 1-methoxy-2-propanol, benzethonium chloride, modified oil ethoxylate, and dodecyl dimethyl betaine.

5. The decontaminant for actinide nuclide contamination according to claim 1, characterized in that: The decontaminant for actinide nuclide contamination is used for removing actinide nuclides from any one of equipment surface, ground, tools and personnel body surface.

6. The decontaminant for actinide nuclide contamination according to claim 1, characterized in that: The actinide nuclides include one or more of uranium-238, plutonium-242, and thorium-232.

7. A method for preparing a decontaminant for actinide nuclide contamination, characterized in that: The steps include: Step 1, weighing each raw material in proportion, adding the chelating agent into water, heating and dissolving, and obtaining a chelating agent solution; Step 2, adding a surfactant to the chelating agent solution of step 1, heating and dissolving, to obtain a composite solution; Step 3: adding the auxiliary agent to the compound solution described in step 2 to obtain a decontaminant for actinide nuclide contamination.

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