Acrylate matrix for radioactive organic waste liquid curing and preparation method and application thereof

Abstract

The invention provides an acrylate matrix for radioactive organic waste liquid curing and a preparation method and application thereof. The acrylate matrix for radioactive organic waste liquid curing comprises an acrylate monomer, an acrylate cross-linking agent and a free radical initiator, wherein the free radical initiator comprises an initiator and / or an initiation auxiliary agent, the initiator comprises a photoinitiator or a thermal initiator, and the initiation auxiliary agent is a photo-initiation auxiliary agent. The radioactive organic waste liquid solidified body is all organic compounds, the residue amount after incineration is low, and the volume reduction effect is good.

Description

Technical Field

[0001] This invention relates to the field of radioactive waste treatment technology, specifically to an acrylate matrix for solidifying radioactive organic waste liquid, its preparation method, and its application. Background Technology

[0002] With the development of my country's nuclear military, nuclear power, and civilian nuclear technology application industries, the generation of radioactive organic waste liquid is unavoidable during the operation, maintenance, and decommissioning of nuclear facilities. Due to the great difficulty in its treatment, most of it is currently in a state of temporary storage pending treatment. After decades of operation, the accumulation of radioactive waste oil has become considerable, and the pressure of temporary storage and safety hazards are becoming increasingly prominent.

[0003] The main sources of radioactive organic waste liquid include: 1) high-viscosity lubricating oils, such as guide rail oil, engine oil, and vacuum pump oil; 2) tributyl phosphate (TBP) / kerosene produced during solvent extraction at spent fuel reprocessing plants; 3) low-flash-point fuel oils, such as diesel and gasoline; and 4) waste scintillation liquids containing tritium and carbon-14 produced by radiochemical laboratories and environmental monitoring units. Radioactive organic waste liquids typically possess flammable, explosive, thermally decomposable, and irradiated decomposable physicochemical properties, and contain radioactive nuclides such as uranium, plutonium, cerium, strontium, cesium, cobalt, and tritium, posing a significant potential hazard for long-term storage. Unstabilized radioactive organic waste liquids not only pose potential dangers such as combustion and radioactive leakage, but also, if the storage tanks rupture, can rapidly spread, causing widespread environmental pollution and threatening human health and ecological safety.

[0004] Currently, research on treatment methods for radioactive organic waste liquids in the nuclear industry mainly includes incineration, wet oxidation, cement solidification, adsorption, and absorption solidification. Incineration is the most traditional method, with a very high volume reduction coefficient, capable of completely incinerating organic waste liquids into inorganic ash. However, flue gas treatment is difficult and highly corrosive. Wet oxidation operates at low temperatures and has a high volume reduction ratio, but its process flow is long, limiting its practical application. Cement solidification is simple and requires minimal equipment, but it results in a large increase in waste volume and a high leaching rate of pollutants. Adsorption mainly utilizes porous solid adsorbents such as diatomaceous earth and vermiculite to adsorb organic waste liquids onto their surfaces. The process is simple, but the adsorption capacity is small, and organic waste liquids and radionuclides are easily leached. Absorption solidification uses absorbents to absorb and fix radioactive organic waste liquids within the absorbent molecules, forming a stable absorbed solid. It has advantages such as high efficiency and simple operation. The formed absorbed solid can be easily transported and further treated and disposed of, reducing the risks during liquid waste storage and transportation, making it a very promising disposal method.

[0005] Internationally, research on absorbents for organic waste liquids is relatively mature, and some practical applications have been conducted. The main types of absorbents include Imbiber Beads, Nochar, and Petroset. Among them, the "N" series absorbents developed by Nochar Corporation in the United States are considered the most advanced radioactive waste liquid absorbent solidification agents, with N910 specifically designed for radioactive organic waste liquids. However, Nochar Corporation keeps its product preparation technology confidential, and the high price makes it difficult to promote and apply in engineering projects in China. In recent years, domestic scholars have also independently developed some solidification treatment methods for radioactive organic waste liquids. For example, Beijing University of Chemical Technology used bentonite as a thickener, ethanol as an additive, and polyurea as a curing agent to perform composite curing treatment on radioactive waste oil under room temperature stirring (Chinese Patent CN107910091A); China National Nuclear Corporation Sichuan Environmental Protection Engineering Co., Ltd. conducted research on the curing of low-level radioactive waste oil using stearic acid and alkaline solution as curing agents and ethyl cellulose as a thickener under heating conditions (70-100℃) (Chinese Patent CN109545419A); Hunan University of Science and Technology adopted the principle of gelation-encapsulation composite synergistic curing, using sodium hydroxide and stearic acid as emulsifiers, activated carbon and starch as absorbents, and ethyl cellulose as a thickener, and achieved the curing treatment of low-level radioactive waste oil by heating (70-90℃) (Chinese Patent CN109524144A). However, the above methods still have the following shortcomings: First, the oil seepage rate is relatively high, and the absorption and solidification effect needs to be improved; second, the strength of the solidified body is low, and there is a risk of scattering during transportation; in addition, most of the above methods require the addition of inorganic substances, which will form radioactive residues in the subsequent incineration process, which is not conducive to waste minimization.

[0006] In general, foreign organic waste liquid absorbents face monopoly and economic challenges, making them difficult to promote and apply in engineering projects in China. Meanwhile, research and progress in the absorption and solidification of radioactive organic waste liquids in my country are relatively limited. Therefore, this invention proposes an acrylate matrix for the solidification of radioactive organic waste liquids, its preparation method, and its application. Summary of the Invention

[0007] In view of the limited research and progress made in the absorption and solidification of radioactive organic waste liquid, this invention provides an acrylate matrix for the solidification of radioactive organic waste liquid, its preparation method, and its application.

[0008] The technical method of the present invention is as follows: An acrylate matrix for solidifying radioactive organic waste liquid, the acrylate matrix comprising: acrylate monomer, acrylate crosslinking agent, and free radical initiator; wherein the free radical initiator comprises an initiator and / or an initiation aid, the initiator comprising a photoinitiator or a thermal initiator, and the initiation aid being a photoinitiation aid.

[0009] Optionally, the components include the following parts: 20-80 parts of acrylate monomer, 80-20 parts of acrylate crosslinking agent, 0-10 parts of initiator, and 0-5 parts of initiation aid; wherein the initiator includes a photoinitiator or a thermal initiator, with the photoinitiator being 0.1-2 parts and the thermal initiator being 1-10 parts.

[0010] Optionally, the acrylate monomers include one or more of methyl acrylate, ethyl acrylate, butyl acrylate, isobutyl acrylate, hexyl acrylate, isooctyl acrylate, lauryl acrylate, benzyl acrylate, cyclohexyl acrylate, isobornyl acrylate, hexadecyl acrylate, octadecyl acrylate, and the corresponding methacrylates.

[0011] Optionally, the acrylate crosslinking agent is a bifunctional or polyfunctional acrylate; the bifunctional or polyfunctional acrylate includes one or more of 1,6-hexanediol diacrylate, decane-1,10-dimethyl diacrylate, tricyclo[5.2.1.02,6]decanedimethyl acrylate, polybutadiene diacrylate, pentaerythritol tetrapropionate, dipentaerythritol hexaacrylate, and the corresponding methacrylates.

[0012] Optionally, the photoinitiator comprises one or more of 2,4,6-trimethylbenzoylphenylphosphonate, 2,4,6-(trimethylbenzoyl)diphenylphosphine oxide, 2-hydroxy-2-methyl-1-phenyl-1-propanone, and 1-hydroxycyclohexylbenzophenone; the photoinitiator is a polythiol compound, and the polythiol compound is a (mercaptopropyl)methylsiloxane homopolymer.

[0013] Optionally, the thermal initiator includes one or more of benzoyl peroxide, azobisisobutyronitrile, tert-butyl peroxide, and diisopropyl peroxide.

[0014] The present invention also provides a method for preparing an acrylate matrix for solidifying radioactive organic waste liquid, comprising the following steps: mixing acrylate monomers and acrylate crosslinking agents, then adding a free radical initiator, mixing evenly to obtain the acrylate matrix.

[0015] The present invention also provides a method for solidifying radioactive organic waste liquid, characterized in that the method uses the above-mentioned acrylate matrix for solidifying radioactive organic waste liquid, and the solidification method includes photo-initiated crosslinking solidification or thermally initiated crosslinking solidification.

[0016] Optionally, the photo-initiated crosslinking curing includes the following steps: mixing the radioactive organic waste liquid to be cured with an acrylate matrix, stirring evenly, and then subjecting the acrylate matrix to rapid crosslinking polymerization under room temperature and light conditions to obtain a cured body; wherein, the acrylate matrix includes acrylate monomers, acrylate crosslinking agents, and free radical initiators; wherein, the free radical initiator includes an initiator and / or an initiation auxiliary, the initiator being a photoinitiator and the initiation auxiliary being a photoinitiation auxiliary; the radioactive organic waste liquid to be cured is selected from simulated radioactive organic waste liquid; the light conditions include ultraviolet curing lamps and / or xenon lamp light sources, and the light exposure time is 1~5 min.

[0017] Optionally, the thermally initiated crosslinking curing includes the following steps: mixing the radioactive organic waste liquid to be cured with an acrylate matrix, stirring evenly, and then allowing it to stand for a period of time under heating conditions, causing the acrylate matrix to undergo crosslinking polymerization to obtain a cured body; wherein, the acrylate matrix includes acrylate monomers, acrylate crosslinking agents, and free radical initiators; wherein, the free radical initiator is a thermal initiator; the radioactive organic waste liquid to be cured is selected as a simulated radioactive organic waste liquid; the heating temperature is 70~110 ℃; and the standing time is 2~30 min.

[0018] The beneficial effects of this invention are: I. The radioactive organic waste liquid solidified body of the present invention is entirely composed of organic compounds, and has low residue after incineration and good volume reduction effect.

[0019] II. The radioactive organic waste liquid solidified body of the present invention has high strength and rigidity, can withstand large loads, has low volume expansion rate, and has high thermal stability and radiation resistance stability, and can be used as a final disposal solution.

[0020] III. The present invention is based on a photo / thermal crosslinking method for in-situ absorption and solidification of radioactive organic waste liquid. Using acrylate as a matrix, free radical crosslinking polymerization occurs under the action of light, heat and initiator, fixing the organic waste liquid in situ in the polymer network. It has fast solidification speed, low oil leakage rate, simple operation and easy-to-obtain raw materials, and can realize the rapid treatment of radioactive organic waste liquid. Attached Figure Description

[0021] Figure 1 This is a photograph of the guide rail oil before in-situ photocuring in Embodiment 8 of the present invention; Figure 2 This is a photograph of the guide rail oil after in-situ photocuring in Embodiment 8 of the present invention; Figure 3 This is a photograph of the guide rail before curing in the light-curing amplification experiment of Embodiment 15 of the present invention; Figure 4This is a photograph of the guide rail after curing in the light-curing magnification experiment of Embodiment 15 of the present invention; Figure 5 This is a photograph of the guide rail before the thermosetting oil in the scale-up experiment of Embodiment 21 of the present invention has cured; Figure 6 This is a photograph of the guide rail oil after curing in the thermosetting amplification experiment of Embodiment 21 of the present invention; Figure 7 This is a photograph of the cured body in Example 8 of the present invention before irradiation; Figure 8 This is a photograph of the cured body after irradiation in Example 8 of the present invention; Figure 9 Thermogravimetric analysis curves of the cured body of this invention and the comparative example are shown. Figure 10 This is a diagram showing the compressive stress-strain curves of the cured body of the present invention before and after γ-irradiation; Figure 11 This is a photograph of the cured body of Embodiment 22 of the present invention before it was dropped freely from a height of 3 m. Figure 12 This is a photograph of the cured body of Embodiment 22 of the present invention after it has been dropped freely from a height of 3 m. Detailed Implementation

[0022] The technical solution of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] This invention provides an acrylate matrix for solidifying radioactive organic waste liquid, comprising: acrylate monomer, acrylate crosslinking agent, and free radical initiator.

[0024] The free radical initiator includes an initiator and / or an initiation aid. The initiator includes a photoinitiator or a thermal initiator, and the initiation aid is a photoinitiation aid.

[0025] The present invention selects acrylate as the matrix, which has the following advantages: 1) The olefin groups of acrylate are very easy to polymerize under the action of light, heat and initiators; 2) There are many types of acrylate monomers, which are diverse and have low viscosity, making them easy to mix with oils; 3) Acrylic polymers have been developed as highly oil-absorbing resins, indicating their potential for oil-absorbing curing. For example, Chinese patent CN111292865A premixes highly oil-absorbing acrylate copolymer resin with radioactive waste oil and then performs cement curing, which can reduce the leaching rate of the cement-cured body; 4) Polyacrylate crosslinked polymers have high strength and stiffness, can withstand large loads, and have high thermal and chemical stability.

[0026] In this embodiment, the components include the following proportions: 20-80 parts of acrylate monomer, 80-20 parts of... The mixture contains an acrylate crosslinking agent, 0 to 10 parts of an initiator, and 0 to 5 parts of an initiation aid. Here, the initiator includes a photoinitiator or a thermal initiator, with the photoinitiator comprising 0.1 to 2 parts and the thermal initiator comprising 1 to 10 parts.

[0027] In this embodiment, the acrylate monomers include methyl acrylate, ethyl acrylate, butyl acrylate, isobutyl acrylate, hexyl acrylate, isooctyl acrylate, lauryl acrylate, benzyl acrylate, cyclohexyl acrylate, isobornyl acrylate, hexadecyl acrylate, octadecyl acrylate, etc., and one or more of the corresponding methacrylates. Here, the corresponding methacrylates include methyl methacrylate, ethyl methacrylate, butyl methacrylate, isobutyl methacrylate, hexyl methacrylate, isooctyl methacrylate, lauryl acrylate, benzyl methacrylate, cyclohexyl methacrylate, isobornyl methacrylate, hexadecyl methacrylate, octadecyl methacrylate, etc.

[0028] In this embodiment, the acrylate crosslinking agent is a bifunctional or polyfunctional acrylate. Bifunctional or polyfunctional acrylates include 1,6-hexanediol diacrylate, decane-1,10-dimethyldiacrylate, tricyclo[5.2.1.02,6]decanedimethylacrylic acid, polybutadiene diacrylate, pentaerythritol tetrapropionate, dipentaerythritol hexamethacrylate, and one or more of the corresponding methacrylates. Here, the corresponding methacrylates include 1,6-hexanediol dimethacrylate, decane-1,10-dimethyldimethacrylate, polybutadiene dimethacrylate, pentaerythritol tetrapropylmethacrylate, dipentaerythritol hexamethacrylate, etc.

[0029] In this embodiment, the photoinitiator includes one or more of ethyl 2,4,6-trimethylbenzoylphenylphosphonate (TPO-L), 2,4,6-(trimethylbenzoyl)diphenylphosphine oxide (TPO), 2-hydroxy-2-methyl-1-phenyl-1-propanone (1173), and 1-hydroxycyclohexylbenzophenone (184), with TPO-L being preferred. The photoinitiator is a polythiol compound used to increase the photocuring depth, with (mercaptopropyl)methylsiloxane homopolymer (SMS-992) being preferred.

[0030] In this embodiment, the thermal initiator includes one or more of benzoyl peroxide (BPO), azobisisobutyronitrile (AIBN), tert-butyl peroxide (TBPB), and diisopropyl peroxide, with BPO being preferred.

[0031] The present invention also provides a method for preparing an acrylate matrix for solidifying radioactive organic waste liquid, comprising the following steps: mixing acrylate monomers and acrylate crosslinking agents, then adding a free radical initiator, mixing evenly to obtain the acrylate matrix.

[0032] The present invention also provides a method for solidifying radioactive organic waste liquid, characterized in that the method uses the above-mentioned acrylate matrix for solidifying radioactive organic waste liquid, and the solidification method includes photo-initiated crosslinking solidification or thermally initiated crosslinking solidification.

[0033] In this embodiment, photo-initiated crosslinking curing includes the following steps: mixing the radioactive organic waste liquid to be cured with an acrylate matrix, stirring evenly, and then rapidly crosslinking and polymerizing the acrylate matrix under room temperature and light conditions (specifically, under ultraviolet light), thereby solidifying the organic waste liquid in situ within the polymer to form a block-shaped cured body with high mechanical strength.

[0034] The acrylate matrix includes acrylate monomers, acrylate crosslinking agents, and free radical initiators; wherein the free radical initiator includes an initiator and / or an initiation aid, wherein the initiator is a photoinitiator and the initiation aid is a photoinitiation aid.

[0035] In this embodiment, the radioactive organic waste liquid to be solidified is selected from simulated radioactive organic waste liquid, including guide rail oil, vacuum pump oil, diesel oil, 30% tributyl phosphate (TBP) / kerosene, etc.

[0036] In this embodiment, the illumination conditions include ultraviolet curing lamps and / or xenon lamp light sources, and the illumination time is 1~5 min.

[0037] In this embodiment, the ratio (oil-to-matter ratio) of the radioactive organic waste liquid to be solidified to the acrylate matrix is ​​0.5:1 to 5:1. For example, the ratio can be 1.5:1 or 2:1.

[0038] In this embodiment, thermally initiated crosslinking curing includes the following steps: mixing the radioactive organic waste liquid to be cured with an acrylate matrix, stirring evenly, and then letting it stand for a period of time under heating conditions. The acrylate matrix undergoes crosslinking polymerization, and the organic waste liquid is cured in situ inside the polymer to form a block-shaped cured body with high mechanical strength.

[0039] The acrylate matrix includes acrylate monomers, acrylate crosslinking agents, and free radical initiators; the free radical initiator is a thermal initiator.

[0040] In this embodiment, the radioactive organic waste liquid to be solidified is selected from simulated radioactive organic waste liquid, including guide rail oil, vacuum pump oil, diesel oil, 30% TBP / kerosene, etc.

[0041] In this embodiment, the heating temperature is 70~110 ℃.

[0042] In this embodiment, the settling time is 2 to 30 minutes.

[0043] The oil penetration rate test procedure of this invention is as follows: At room temperature, a certain weight of the cured body (m) is weighed and subjected to normal pressure or pressure (0.1 kg / cm²). 2 Under certain conditions, the material is placed on a multi-layered filter paper of known weight (m0). After a certain period of time, the weight of the multi-layered filter paper (m) is measured. t ), through formula (m t The oil penetration rate of the solidified material over a certain period of time is calculated using (-m0) / m*100%. Background subtraction is performed using blank filter paper without the solidified material to eliminate errors caused by variations in filter paper weight due to factors such as humidity.

[0044] The test procedure for volume increase ratio is as follows: a certain volume of organic waste liquid (V0) is measured, mixed with acrylate matrix according to a certain oil-to-liquid ratio and cured, and the volume of the cured body (V1) is tested by water injection method. The volume increase ratio is calculated by formula (V1-V0) / V0*100%.

[0045] Mechanical property testing includes testing the compressive strength and compressive modulus of the cured body using an electronic universal testing machine, and testing the hardness of the cured body using a Shore hardness tester.

[0046] Thermogravimetric analysis (TGA) was used to examine the thermal stability of the solidified body and the residual weight after high-temperature decomposition (to predict the residue rate after incineration). Specific conditions were: argon atmosphere, heating rate 10 °C / min, room temperature ~ 600 °C.

[0047] The radiation resistance test procedure is as follows: the cured body is exposed to γ-rays at a dose rate of 10 kGy / h ( 60 Irradiated with Co for 50 h (cumulative dose 500 kGy), the appearance and morphology changes of the cured body after irradiation were observed, and the compressibility and hardness of the cured body before and after irradiation were measured.

[0048] In this invention, unless otherwise specified, all raw materials used in the preparation are commercially available products well known to those skilled in the art.

[0049] The present invention will be described in detail below through embodiments and experimental examples. However, these are merely examples and do not limit the present invention in any way.

[0050] Example 1 Lauryl methacrylate (LMA, 0.2 g) and 1,6-hexanediol diacrylate (HDDA, 0.8 g) were weighed out, and TPO-L (0.01 g) was added as a photoinitiator. Then, guide rail oil (1.0 g) was added at an oil-to-weight ratio of 1:1 and mixed thoroughly. The mixture was cured by irradiation under a UV curing lamp (395 nm) for 1 min, resulting in a block-shaped cured body with a certain mechanical strength. The cured body was placed on multilayer filter paper for an oil penetration rate test; the oil penetration rate after 28 days under normal pressure was 2.55%.

[0051] Example 2 Lauryl methacrylate (LMA, 0.4 g) and 1,6-hexanediol diacrylate (HDDA, 0.6 g) were weighed out, and TPO-L (0.01 g) was added as a photoinitiator. Then, guide rail oil (1.0 g) was added at an oil-to-weight ratio of 1:1 and mixed thoroughly. The mixture was cured by irradiation under a UV curing lamp (395 nm) for 1 min, and the guide rail oil was completely encapsulated in the cured body, resulting in a block-shaped cured body with a certain mechanical strength. The cured body was placed on multilayer filter paper for an oil penetration rate test. The oil penetration rate under normal pressure after 28 days was 0.18%.

[0052] Example 3 Lauryl methacrylate (LMA, 0.6 g) and 1,6-hexanediol diacrylate (HDDA, 0.4 g) were weighed out, and TPO-L (0.01 g) was added as a photoinitiator. Then, guide rail oil (1.0 g) was added at an oil-to-weight ratio of 1:1 and mixed thoroughly. The mixture was cured by irradiation under a UV curing lamp (395 nm) for 1 min, resulting in a block-shaped cured body with a certain mechanical strength. The cured body was placed on multilayer filter paper for an oil penetration rate test; the oil penetration rate under normal pressure after 28 days was 5.45%.

[0053] Example 4 Weigh out octadecyl methacrylate (ODMA, 8 g) and 1,6-hexanediol diacrylate (HDDA, 12 g), add TPO-L (0.2 g) as a photoinitiator, and then add guide rail oil (20 g) at an oil-to-weight ratio of 1:1, and mix thoroughly. Place the mixture in glass test tubes and petri dishes respectively, and cure under UV curing lamp (395 nm) for 1 min on each side. The resulting cylindrical and disc-shaped cured bodies were used for compressive strength and hardness tests, respectively. After curing approximately 2 g of the mixture, place the cured body on multilayer filter paper for oil penetration rate testing. The oil penetration rate was 0.02% under normal pressure after 15 days and 0.1 kg / cm² after 28 days. 2 The oil penetration rate was 0.32%.

[0054] Example 5 Weigh out octadecyl methacrylate (ODMA, 8 g) and 1,6-hexanediol diacrylate (HDDA, 12 g), add TPO-L (0.2 g) as a photoinitiator, and then add guide rail oil (30 g) at an oil-to-mass ratio of 1.5:1, and mix thoroughly. Place the mixture in glass test tubes and petri dishes respectively, and cure under a UV curing lamp (395 nm) for 1 min on each side to complete the curing. The resulting cylindrical and disc-shaped cured bodies were used for compressive strength and hardness tests, respectively. After curing approximately 2.5 g of the mixture, place the cured body on multilayer filter paper for an oil penetration rate test. The oil penetration rate was 1.18% under normal pressure after 41 days and 0.1 kg / cm² after 28 days. 2 The oil penetration rate was 4.08%.

[0055] Example 6 Weigh out octadecyl methacrylate (ODMA, 8 g), 1,6-hexanediol diacrylate (HDDA, 6 g), and decane-1,10-dimethyl diacrylate (DDDA, 6 g), add TPO-L (0.2 g) as a photoinitiator, and then add guide rail oil (30 g) at an oil-to-mass ratio of 1.5:1, and mix thoroughly. Place the mixture in glass test tubes and petri dishes respectively, and cure under a UV curing lamp (395 nm) for 1 min on each side to complete the curing. The resulting cylindrical and disc-shaped cured bodies were used for compressive strength and hardness tests, respectively. After curing approximately 2.5 g of the mixture, place the cured body on multilayer filter paper for an oil penetration rate test. The oil penetration rate was 0.37% under normal pressure after 41 days and 0.1 kg / cm² after 28 days. 2 The oil penetration rate was 2.71%.

[0056] Example 7 Weigh out hexadecyl acrylate (HDA, 0.4 g), 1,6-hexanediol diacrylate (HDDA, 0.3 g), and decane-1,10-dimethyl diacrylate (DDDA, 0.3 g). Add TPO-L (0.01 g) as a photoinitiator, and then add guide rail oil (1.5 g) at an oil-to-mass ratio of 1.5:1, and mix thoroughly. Curing the mixture under a UV curing lamp (395 nm) for 1 min completes the curing process. The guide rail oil is completely encapsulated in the cured body, resulting in a block-shaped cured body with a certain mechanical strength. The cured body was placed on multilayer filter paper for an oil penetration rate test. After 20 days at normal pressure, the oil penetration rate was 1.31%.

[0057] Example 8 Weigh out octadecyl methacrylate (ODMA, 8 g) and tricyclo[5.2.1.02,6]decanedimethylacrylic acid (TCDMA, 12 g), add TPO-L (0.2 g) as a photoinitiator, and then add guide rail oil (30 g) at an oil-to-mass ratio of 1.5:1, and mix thoroughly. Place the mixture in glass test tubes and petri dishes respectively, and cure under a UV curing lamp (395 nm) for 1 min on each side to complete the curing. The resulting cylindrical and disc-shaped cured bodies were used for compressive strength and hardness tests, respectively. After curing about 2.5 g of the mixture, place the cured body on multilayer filter paper for an oil penetration rate test. The oil penetration rate at normal pressure after 28 days was 0.01%.

[0058] Example 9 Weigh out octadecyl methacrylate (ODMA, 8 g) and tricyclo[5.2.1.02,6]decanedimethylacrylic acid (TCDMA, 12 g), add TPO-L (0.2 g) as a photoinitiator, and then add guide rail oil (20 g) at an oil-to-weight ratio of 1:1, and mix thoroughly. Place the mixture in glass test tubes and petri dishes respectively, and cure under a UV curing lamp (395 nm) for 1 min on each side to complete the curing. The resulting cylindrical and disc-shaped cured bodies were used for compressive strength and hardness tests, respectively. After curing about 2 g of the mixture, place the cured body on multilayer filter paper for an oil penetration rate test, and apply pressure (0.1 kg / cm²) for 28 days. 2 The oil seepage rate was 0.05%.

[0059] Example 10 Weigh out octadecyl methacrylate (ODMA, 8 g) and tricyclo[5.2.1.02,6]decanedimethylacrylic acid (TCDMA, 12 g), add TPO-L (0.2 g) as a photoinitiator, and then add guide rail oil (40 g) at an oil-to-mass ratio of 2:1, and mix thoroughly. Place the mixture in glass test tubes and petri dishes respectively, and cure under UV curing lamp (395 nm) for 1 min on each side. The resulting cylindrical and disc-shaped cured bodies were used for compressive strength and hardness tests, respectively. After curing about 3 g of the mixture, place the cured body on multilayer filter paper for oil penetration rate testing. The oil penetration rate after 28 days at normal pressure was 0.44%, and the rate after 28 days under pressure (0.1 kg / cm²) was... 2 The oil penetration rate was 1.13%.

[0060] Example 11 Octadecyl methacrylate (ODMA, 0.4 g) and tricyclo[5.2.1.02,6]decanedimethylacrylic acid (TCDMA, 0.6 g) were weighed out, and TPO-L (0.01 g) was added as a photoinitiator. Then, guide rail oil (3.0 g) was added at an oil-to-mass ratio of 3:1 and mixed thoroughly. The mixture was cured by irradiation under a UV curing lamp (395 nm) for 1 min. The guide rail oil was completely encapsulated in the cured body, resulting in a block-shaped cured body with a certain mechanical strength. The cured body was placed on multilayer filter paper for an oil penetration rate test. The oil penetration rate under normal pressure after 28 days was 3.63%.

[0061] Example 12 Octadecyl methacrylate (ODMA, 0.4 g) and tricyclo[5.2.1.02,6]decanedimethylacrylic acid (TCDMA, 0.6 g) were weighed out, and TPO-L (0.01 g) was added as a photoinitiator. Diesel oil (2.0 g) was then added at an oil-to-mass ratio of 2:1, and the mixture was thoroughly mixed. The mixture was cured by irradiation under a UV curing lamp (395 nm) for 1 min to obtain a block-shaped cured body with certain mechanical strength. The cured body was placed on multilayer filter paper for an oil permeation rate test. After 28 days at normal pressure, the oil permeation rate was 0.17%.

[0062] Example 13 Octadecyl methacrylate (ODMA, 0.4 g) and tricyclo[5.2.1.02,6]decanedimethylacrylic acid (TCDMA, 0.6 g) were weighed out, and TPO-L (0.01 g) was added as a photoinitiator. Then, 30% TBP / kerosene (2.0 g) was added at an oil-to-mass ratio of 2:1 and mixed thoroughly. The mixture was cured by irradiation under a UV curing lamp (395 nm) for 1 min to obtain a block-shaped cured body with certain mechanical strength. The cured body was placed on multilayer filter paper for oil penetration rate testing. The oil penetration rate under normal pressure after 28 days was 0.03%.

[0063] Example 14 Octadecyl methacrylate (ODMA, 0.4 g) and tricyclo[5.2.1.02,6]decanedimethylacrylic acid (TCDMA, 0.6 g) were weighed out, and TPO-L (0.01 g) was added as a photoinitiator. Pump oil (2.0 g) was then added at an oil-to-mass ratio of 2:1, and the mixture was thoroughly mixed. The mixture was cured by irradiation under a UV curing lamp (395 nm) for 1 min to obtain a block-shaped cured body with certain mechanical strength. The cured body was placed on multilayer filter paper for an oil permeation rate test; the oil permeation rate under normal pressure after 28 days was 4.92%.

[0064] Example 15 Photopolymerization scale-up experiment: Octadecyl methacrylate (ODMA, 32 g) and tricyclo[5.2.1.02,6]decanedimethylacrylic acid (TCDMA, 48 g) were weighed. TPO-L (0.6 g) was added as a photoinitiator, and SMS-992 (1.6 g) was added as a photoinitiating aid. Then, guide rail oil (120 g) was added at an oil-to-mass ratio of 1.5:1 and mixed thoroughly. The mixture was poured into a 15.5 cm diameter petri dish (liquid height 1.5 cm) and cured under a UV curing lamp (395 nm) for 5 min. The guide rail oil was completely encapsulated in the cured body, resulting in a block-shaped cured body with certain mechanical strength. The cured body was placed on multilayer filter paper for an oil penetration rate test, and pressure (0.1 kg / cm²) was applied for 28 days. 2 The oil penetration rate was 0.35%.

[0065] Example 16 Weigh out octadecyl methacrylate (ODMA, 2.0 g) and tricyclo[5.2.1.02,6]decanedimethylacrylic acid (TCDMA, 3.0 g), add BPO (0.25 g) as a thermal initiator, and then add rail oil (7.5 g) at an oil-to-weight ratio of 1.5:1, and mix thoroughly. Heat the mixture to 100°C under static conditions. o C. Curing is completed in approximately 5 minutes, resulting in a block-shaped cured body with a certain mechanical strength. The cured body was placed on multi-layer filter paper for an oil permeation rate test. The oil permeation rate was 0.07% under normal pressure after 28 days, and under pressure (0.1 kg / cm²) after 28 days... 2 The oil penetration rate was 0.20%.

[0066] Example 17 Weigh out octadecyl methacrylate (ODMA, 0.4 g) and tricyclo[5.2.1.02,6]decanedimethylacrylic acid (TCDMA, 0.6 g), add AIBN (0.05 g) as a thermal initiator, and then add rail oil (1.5 g) at an oil-to-weight ratio of 1.5:1, and mix thoroughly. Heat the mixture to 80°C under static conditions. o C. Curing is completed in approximately 15 minutes, resulting in a block-shaped cured body with a certain mechanical strength. The cured body was placed on multi-layer filter paper for an oil permeation rate test; the oil permeation rate under normal pressure after 28 days was 0.14%.

[0067] Example 18 Weigh out octadecyl methacrylate (ODMA, 0.4 g) and tricyclo[5.2.1.02,6]decanedimethylacrylic acid (TCDMA, 0.6 g), add BPO (0.05 g) as a thermal initiator, and then add diesel oil (1.5 g) at an oil-to-mass ratio of 1.5:1, and mix thoroughly. Heat the mixture to 100°C under static conditions.o C. Curing is completed in approximately 3 minutes, resulting in a block-shaped cured body with a certain mechanical strength. The cured body was placed on multi-layer filter paper for an oil seepage rate test; the oil seepage rate under normal pressure was 0% after 28 days.

[0068] Example 19 Weigh out octadecyl methacrylate (ODMA, 0.4 g) and tricyclo[5.2.1.02,6]decanedimethylacrylic acid (TCDMA, 0.6 g), add BPO (0.05 g) as a thermal initiator, and then add 30% TBP / kerosene (1.5 g) at an oil-to-mass ratio of 1.5:1, and mix thoroughly. Heat the mixture to 100°C under static conditions. o C. Curing is completed in approximately 7 minutes, resulting in a block-shaped cured body with a certain mechanical strength. The cured body was placed on multi-layer filter paper for an oil seepage rate test; the oil seepage rate under normal pressure after 28 days was 0.03%.

[0069] Example 20 Weigh out octadecyl methacrylate (ODMA, 0.4 g) and tricyclo[5.2.1.02,6]decanedimethylacrylic acid (TCDMA, 0.6 g), add BPO (0.05 g) as a thermal initiator, and then add pump oil (1.5 g) at an oil-to-mass ratio of 1.5:1, and mix thoroughly. Heat the mixture to 100°C under static conditions. o C. Curing is completed in approximately 3 minutes, resulting in a block-shaped cured body with a certain mechanical strength. The cured body was placed on multi-layer filter paper for an oil permeation rate test; the oil permeation rate under normal pressure after 28 days was 0.38%.

[0070] Example 21 Thermosetting scale-up experiment: Weigh octadecyl methacrylate (ODMA, 32 g) and tricyclo[5.2.1.02,6]decanedimethylacrylic acid (TCDMA, 48 g), add TPO-L (4.0 g) as a thermal initiator, and then add guide rail oil (120 g) at an oil-to-mass ratio of 1.5:1, and mix thoroughly. Pour the mixture into a 15.5 cm diameter petri dish and heat to 110°C. o Curing is completed in approximately 4 minutes after step C, resulting in a block-shaped cured body with a certain mechanical strength. The cured body was then placed on multi-layer filter paper for an oil permeation rate test; the oil permeation rate under normal pressure after 28 days was 0.09%.

[0071] Example 22 Impact resistance test of the cured body: A disc-shaped cured body with a diameter of 5.5 cm, a thickness of 0.7 cm, and a weight of 16.32 g was prepared according to Example 8. The cured body was dropped naturally from a height of 3 m onto a ceramic tile floor, and the morphological changes were observed. The results showed that the cured body remained intact after being dropped from a height of 3 m, without cracks or damage, indicating that the cured body has high impact resistance.

[0072] Comparative Example 1 Weigh out 0.5 g of N910 powder, and then add 1.5 g of guide rail oil to it at an oil-to-mass ratio of 3:1. After standing at room temperature for 24 h to absorb the oil, place the solidified powder on multilayer filter paper for an oil penetration rate test. The oil penetration rate after 28 days at normal pressure was 0.33%, and the rate after 28 days under pressure (0.1 kg / cm²) was... 2 The oil penetration rate was 1.09%.

[0073] Comparative Example 2 Weigh out 0.5 g of N910 powder, and then add 1.5 g of diesel oil to it at an oil-to-mass ratio of 3:1. After standing at room temperature for 24 h for absorption, place the solidified powder on multilayer filter paper for an oil penetration rate test. The oil penetration rate at normal pressure after 12 days was 0.08%.

[0074] Comparative Example 3 Weigh out 0.5 g of N910 powder, and then add 1.5 g of 30% TBP / kerosene at an oil-to-mass ratio of 3:1. After standing at room temperature for 24 h of absorption, place the solidified powder on multilayer filter paper for an oil penetration rate test. The oil penetration rate at normal pressure after 12 days was 10.2%.

[0075] Comparative Example 4 Weigh out 0.5 g of N910 powder, and then add 1.5 g of pump oil to it at an oil-to-mass ratio of 3:1. After standing at room temperature for 24 h for absorption, place the solidified powder on multilayer filter paper for an oil penetration rate test. The oil penetration rate at normal pressure after 12 days was 3.6%.

[0076] Figure 1 and Figure 2 These are photographs of the guide rail oil before and after in-situ photocuring in Embodiment 8 of the present invention; Figure 3 and Figure 4 These are photos of the guide rail before and after curing in the light-curing magnification experiment of Embodiment 15 of the present invention; Figure 5 and Figure 6 These are photos of the guide rail oil before and after curing in the thermosetting scale-up experiment of Embodiment 21 of the present invention; Figure 7 and Figure 8 These are photographs of the cured body before and after irradiation in Example 8 of the present invention; Figure 9 Thermogravimetric analysis curves of the cured body of this invention and the comparative example are shown. Figure 10This is a diagram showing the compressive stress-strain curves of the cured body of the present invention before and after γ-irradiation. Figure 11 This is a photograph of the cured body of Embodiment 22 of the present invention before it was dropped freely from a height of 3m. Figure 12 The photograph shows the cured body of Embodiment 22 of the present invention after being dropped freely from a height of 3m. It can be seen that the cured body did not show obvious breakage or damage after being dropped from a height, indicating that it has high impact resistance and reduces the risk of leakage during transportation.

[0077] Table 1. Comparison of oil penetration rates between embodiments of the present invention, comparative examples, and domestic invention patents. Note: Patent 1, CN107910091A; Patent 2, CN109545419A; Patent 3, CN109524144A. Unless otherwise specified, the oil seepage rate under normal pressure and pressure is the 28-day oil seepage rate, where the pressure for the pressure seepage rate is 0.1 kg / cm². 2 a: 15-day oil penetration rate; b: 41-day oil penetration rate; c: 20-day oil penetration rate; d: 12-day oil penetration rate; e: 7-day oil penetration rate; f: 30-day oil penetration rate.

[0078] As shown in Table 1, the curing performance of the embodiments of the present invention with imported N910 products and domestic invention patents on oils is compared. It can be seen that, using ODMA and TCDMA as acrylate matrices, at an oil-to-weight ratio of 2:1, its oil retention effect on guide rail oil (Example 10) and diesel oil (Example 12) is comparable to that of imported product N910 (comparative example, oil-to-weight ratio 3:1) (atmospheric pressure oil penetration rate <1%). In particular, its oil retention effect on TBP / kerosene (Example 13) (atmospheric pressure oil penetration rate 0.03%) is significantly better than that of N910 (atmospheric pressure oil penetration rate 10.2%).

[0079] Table 2. Performance Comparison of Embodiments of the Invention with Comparative Examples and Domestic Invention Patents Note: Patent 1, CN107910091A; Patent 2, CN109545419A; Patent 3, CN109524144A.

[0080] Table 2 shows a comparison of the volume expansion rate and incineration residual weight rate of the solidified body of this invention with imported N910 products and domestic invention patents. It can be seen that the volume expansion rate of the solidified body of this invention is much lower than that of the imported N910 product, and comparable to invention patents 1 and 3. A lower volume expansion rate can reduce the storage space required for the solidified body and improve disposal efficiency. Figure 9 The thermogravimetric analysis curves of the cured body described in this invention and the comparative example show that the cured body has two stages of mass loss. The first stage starts from 175°C. o C to 350o C, mainly due to the thermal decomposition and weight loss of the guide rail oil, the second stage from 350 o C to 470 o C, mainly due to the thermal decomposition weight loss of the acrylate polymer, indicates that the cured body of the present invention has high thermal stability; at the same time, its residual weight rate is close to 0%, indicating that the cured body of the present invention has a good volume reduction effect after incineration.

[0081] Table 3. Changes in compressibility and hardness before and after irradiation in embodiments of the present invention. Table 3 shows the changes in compressive strength and Shore hardness of the solidified body of the present invention before and after γ-irradiation (500 kGy). It can be seen that the solidified body of the present invention has high compressive strength, with Example 9 achieving a compressive strength of 9.7 MPa, meeting the requirement of GB14569.2 for a compressive strength of not less than 7 MPa in plastic solidified bodies of low and medium-level radioactive waste. After γ-irradiation, the compressive strength of the solidified body did not change significantly, but the Shore hardness increased slightly. Figure 8 As can be seen, the appearance of the cured body after irradiation did not change significantly except for a slight yellowing in color, and there were no damages or cracks, indicating that the cured body of the present invention has high radiation resistance stability.

[0082] Various embodiments of the present invention may exist in the form of a range; it should be understood that the description in the form of a range is merely for convenience and brevity and should not be construed as a hard limitation on the scope of the invention; therefore, it should be considered that the range description has specifically disclosed all possible subranges and single numerical values ​​within that range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed subranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and single numbers within the range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. Furthermore, whenever a numerical range is referred to herein, it means including any referenced number (fraction or integer) within the range referred to.

[0083] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An acrylate matrix for solidifying radioactive organic waste liquid, characterized in that, The acrylate matrix comprises: acrylate monomers, acrylate crosslinking agents, and free radical initiators; wherein... The free radical initiator includes an initiator and / or an initiation aid. The initiator includes a photoinitiator or a thermal initiator, and the initiation aid is a photoinitiation aid.

2. The acrylate matrix according to claim 1, characterized in that, The components include the following quantities: 20-80 parts of acrylate monomer, 80-20 parts of acrylate crosslinking agent, 0-10 parts of initiator, and 0-5 parts of initiation aid; wherein the initiator includes photoinitiator or thermal initiator, with 0.1-2 parts of photoinitiator and 1-10 parts of thermal initiator.

3. The acrylate matrix according to claim 1, characterized in that, The acrylate monomers include one or more of the following: methyl acrylate, ethyl acrylate, butyl acrylate, isobutyl acrylate, hexyl acrylate, isooctyl acrylate, lauryl acrylate, benzyl acrylate, cyclohexyl acrylate, isobornyl acrylate, hexadecyl acrylate, octadecyl acrylate, and the corresponding methacrylates.

4. The acrylate matrix according to claim 1, characterized in that, The acrylate crosslinking agent is a difunctional or polyfunctional acrylate; Bifunctional or polyfunctional acrylates include one or more of 1,6-hexanediol diacrylate, decane-1,10-dimethyl diacrylate, tricyclo[5.2.1.02,6]decanedimethyl acrylate, polybutadiene diacrylate, pentaerythritol tetrapropionate, dipentaerythritol hexaacrylate, and the corresponding methacrylates.

5. The acrylate matrix according to claim 1, characterized in that, The photoinitiator includes one or more of the following: ethyl 2,4,6-trimethylbenzoylphenylphosphonate, 2,4,6-(trimethylbenzoyl)diphenylphosphine oxide, 2-hydroxy-2-methyl-1-phenyl-1-propanone, and 1-hydroxycyclohexylphenyl phenone; The photoinitiator is a polythiol compound, which is a homopolymer of (mercaptopropyl)methylsiloxane.

6. The acrylate matrix according to claim 1, characterized in that, The thermal initiator includes one or more of benzoyl peroxide, azobisisobutyronitrile, tert-butyl peroxide, and diisopropyl peroxide.

7. A method for preparing an acrylate matrix for solidifying radioactive organic waste liquid according to any one of claims 1-6, characterized in that, Includes the following steps: The acrylate monomer and acrylate crosslinking agent are mixed, and then a free radical initiator is added and mixed evenly to obtain the acrylate matrix.

8. A method for solidifying radioactive organic waste liquid, characterized in that, The method uses the acrylate matrix for solidifying radioactive organic waste liquid as described in any one of claims 1-6. The curing method includes photo-initiated crosslinking curing or thermally initiated crosslinking curing.

9. The curing method according to claim 8, characterized in that, The photo-initiated crosslinking curing includes the following steps: The radioactive organic waste liquid to be solidified is mixed with an acrylate matrix and stirred evenly. Under room temperature and light conditions, the acrylate matrix undergoes rapid cross-linking polymerization to obtain a solidified body. The acrylate matrix includes acrylate monomers, acrylate crosslinking agents, and free radical initiators; wherein the free radical initiator includes an initiator and / or an initiation auxiliary, the initiator being a photoinitiator and the initiation auxiliary being a photoinitiation auxiliary; The radioactive organic waste liquid to be solidified is selected from simulated radioactive organic waste liquid; The illumination conditions include ultraviolet curing lamps and / or xenon lamps, with an illumination time of 1 to 5 minutes.

10. The curing method according to claim 8, characterized in that, The thermally initiated crosslinking and curing includes the following steps: The radioactive organic waste liquid to be solidified is mixed with an acrylate matrix and stirred evenly. After standing for a period of time under heating conditions, the acrylate matrix undergoes cross-linking polymerization to obtain a solidified body. The acrylate matrix includes acrylate monomers, acrylate crosslinking agents, and free radical initiators; wherein the free radical initiator is a thermal initiator. The radioactive organic waste liquid to be solidified is selected from simulated radioactive organic waste liquid; The heating temperature is 70~110 ℃; The settling time is 2 to 30 minutes.

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