A phosphorus-aluminum-silicate inorganic polymer and a preparation method and application thereof
By using metakaolin and activated calcium oxide as precursors, and combining phosphoric acid solution and aluminum dihydrogen phosphate solution as activators, an inorganic polymer of aluminum phosphate silicate was prepared. This solved the problems of difficult curing of aluminum phosphate silicate inorganic polymer at room temperature and the influence of high alkalinity, and achieved efficient surrounding rock reinforcement and sealing improvement.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- BEIJING RES INST OF URANIUM GEOLOGY
- Filing Date
- 2023-10-26
- Publication Date
- 2026-04-24
AI Technical Summary
Existing phosphorus aluminum silicate inorganic polymers are difficult to cure at room temperature, have high heat release, poor fluidity, and high alkalinity may affect the sealing and buffering performance of high-level radioactive waste geological repositories, leading to damage to the surrounding rock.
Using metakaolin and activated calcium oxide as precursors, and combined with phosphoric acid solution and aluminum dihydrogen phosphate solution as activators, an inorganic polymer of aluminum phosphate silicate was prepared through standard curing, and its setting time and compressive strength were optimized.
It significantly improves the working performance of phosphosaluminosilicate inorganic polymers, reduces setting time, increases compressive strength, meets the sealing and reinforcement requirements of high-level radioactive waste geological repositories, and ensures the stability of the surrounding rock.
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Abstract
Description
Technical Field
[0001] This invention relates to the field of inorganic non-metallic cementitious materials technology, and in particular to an inorganic polymer of phosphoaluminosilicate, its preparation method and application. Background Technology
[0002] In recent years, nuclear energy, as a clean energy source, has been developed and applied on a large scale in my country. However, the resulting large amount of spent fuel urgently needs to be disposed of. Currently, major nuclear power countries internationally generally believe that deep geological disposal measures, which involve burying high-level radioactive waste at depths of 500–1000 meters in geological formations (granite, basalt, salt rock, or argillaceous rock) and permanently isolating it from the human living environment through engineering and natural barrier systems, are the most realistic and reliable methods among various disposal options. However, during the construction of high-level radioactive waste geological disposal sites, the rock mass is subjected to the combined effects of excavation disturbance, groundwater movement, and the swelling of the buffer material engineering barrier. This causes a strong disturbance to the initial stress field of the rock mass, leading to progressive failure processes such as damage, loosening, brittle fracture, spalling, and recompaction in the surrounding rock and fissures. Consequently, this results in drastic changes in the mechanical and transport properties of the surrounding rock.
[0003] In response to these surrounding rocks and fissures, sealing or reinforcing materials must be used during the construction of high-level radioactive waste geological repositories to improve rock properties and reduce or prevent damage to the surrounding rock and fissures. The high alkalinity of existing ordinary silicate cementitious materials may cause an increase in the pH value of the groundwater in the repositories, thereby affecting the effectiveness of the bentonite buffer backfill material, reducing its expansibility, increasing its permeability, and causing significant changes in its pore structure and properties, thus affecting the sealing of the repositories. Therefore, low-pH (pH<11) and highly durable sealing / curing materials are more effective in the storage environment.
[0004] Compared to ordinary silicate cement, the unique high durability and low pH (pH<7) of phosphoroaluminosilicate inorganic polymers allow them to be used in extreme environmental conditions. Studies of building materials such as the Egyptian pyramids built around 2500 BC and the Jericho city in the Jordan Valley region of Palestine dating back to 7000 BC have revealed the presence of microcrystalline and semi-crystalline zeolite-like substances in ancient concrete structures, similar to those found in phosphoroaluminosilicate inorganic polymers. It is speculated that the high durability of ancient concrete stems from these substances. However, phosphoric acid-activated phosphoroaluminosilicate inorganic polymers exhibit significant drawbacks, including difficulty in curing at room temperature, high heat release, and poor fluidity. Although numerous studies and practical experience indicate that high-temperature curing can accelerate the polymerization reaction of phosphoroaluminosilicate inorganic polymers, the practical engineering application context limits the curing methods used in their preparation. Therefore, the performance, setting time, and early strength of phosphoroaluminosilicate inorganic polymers in actual engineering environments are crucial issues that must be addressed for practical engineering applications. Summary of the Invention
[0005] In view of this, the purpose of this invention is to provide a phosphoroaluminosilicate inorganic polymer, its preparation method, and its application. The phosphoroaluminosilicate inorganic polymer provided by this invention can significantly improve the working performance of traditional acid-activated phosphoroaluminosilicate inorganic polymers, effectively reduce the setting time of inorganic polymers, and greatly increase the compressive strength of inorganic polymer aggregates. This invention is of great significance for the application of phosphoroaluminosilicate inorganic polymers in the construction of high-level radioactive waste geological repositories.
[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution:
[0007] This invention provides an inorganic polymer of phosphoaluminosilicate, comprising the following raw materials in parts by weight:
[0008] 50-67 parts of precursor raw material, 33-50 parts of activator, and water;
[0009] The precursor raw materials include metakaolin and activated calcium oxide;
[0010] The active calcium oxide accounts for 3 to 15% of the weight of the precursor raw material;
[0011] The activator comprises a phosphoric acid solution.
[0012] Preferably, in the raw materials for preparing the phosphosaluminosilicate inorganic polymer, the mass ratio (W / S) of liquid to solid is 0.5 to 1.2:1;
[0013] The liquid is water and the water contained in the activator;
[0014] The solid is a precursor raw material.
[0015] Preferably, the active calcium oxide is obtained by calcining limestone at a temperature of 850–1250°C and a holding time of 4 hours.
[0016] Preferably, the activator further includes an aluminum dihydrogen phosphate solution, wherein the molar ratio of H3PO4 to Al(OH)3 in the aluminum dihydrogen phosphate solution is 3.2:1.
[0017] Preferably, the aluminum dihydrogen phosphate solution comprises the following raw materials in parts by weight: 13 parts aluminum hydroxide powder, 61.5 parts phosphoric acid solution with a mass content of 85%, and 25.5 parts water.
[0018] Preferably, the aluminum dihydrogen phosphate solution accounts for 0-70% of the weight of the activator, and is not 0%.
[0019] Preferably, the phosphoric acid solution has a mass content of 85%.
[0020] This invention also provides a method for preparing the phosphoroaluminosilicate inorganic polymer described in the above technical solution, comprising the following steps:
[0021] The activator and water are mixed to obtain a liquid.
[0022] The precursor raw material and liquid are mixed, and the resulting slurry is cured to obtain the phosphoroaluminosilicate inorganic polymer.
[0023] Preferably, the maintenance regime is standard maintenance, wherein the humidity is >95%, the temperature is 20±2℃, and the maintenance period is 7 to 60 days.
[0024] This invention also provides the application of the phosphoroaluminate silicate inorganic polymer described in the above technical solution or the phosphoroaluminate silicate inorganic polymer prepared by the preparation method described in the above technical solution in the construction of high-level radioactive waste geological disposal repositories.
[0025] This invention provides a phosphoroaluminosilicate inorganic polymer comprising the following raw materials in parts by weight: 50-67 parts precursor material, 33-50 parts activator, and water; the precursor material includes metakaolin and activated calcium oxide; the activated calcium oxide accounts for 3-15% of the weight of the precursor material; the activator comprises a phosphoric acid solution. The phosphoroaluminosilicate inorganic polymer product obtained using the formulation of this invention can meet the requirement of a pH value less than 11 for high-level radioactive waste geological repositories sealing materials, and can effectively support fractures and rubble, meeting the requirements for sealing and reinforcement materials in high-level radioactive waste geological repositories. The addition of activated calcium oxide to the precursor material of this invention significantly improves the working performance of traditional acid-activated metakaolin-based inorganic polymers, resulting in good fluidity, curing under standard conditions, reduced setting time, and increased compressive strength of the inorganic polymer aggregate. Attached Figure Description
[0026] Figure 1 The compressive strength of the phosphorus aluminum silicate inorganic polymer is shown in the figure when W / S = 0.8, with metakaolin and activated calcium oxide as precursor raw materials (activated calcium oxide accounts for 3%, 6%, 9%, 12% and 15% of the weight of the precursor raw materials) and phosphoric acid solution as activator.
[0027] Figure 2 The flowability diagram of the phosphoaluminosilicate inorganic polymer with W / S = 0.8, using metakaolin and activated calcium oxide as precursor raw materials (calcium oxide accounts for 3%, 6%, 9%, 12% and 15% of the weight of the precursor raw materials) and phosphoric acid solution as activator.
[0028] Figure 3 The coagulation time diagram of phosphatidic acid silicate inorganic polymer when W / S = 0.8, with metakaolin and activated calcium oxide as precursor raw materials (calcium oxide accounts for 3%, 6%, 9%, 12% and 15% of the weight of the precursor raw materials) and phosphoric acid solution as activator.
[0029] Figure 4 The compressive strength of aluminum phosphate silicate inorganic polymers is shown in the figure when W / S = 0.8, with metakaolin and activated calcium oxide as precursor raw materials (activated calcium oxide accounts for 8% of the weight of the precursor raw materials), and phosphoric acid solution and aluminum dihydrogen phosphate solution as composite activators (aluminum dihydrogen phosphate accounts for 10%, 20%, 30%, 40% and 50% of the weight of the activator).
[0030] Figure 5 The flowability diagram of aluminum phosphate silicate inorganic polymer when W / S = 0.8, with metakaolin and activated calcium oxide as precursor raw materials (activated calcium oxide accounts for 8% of the weight of precursor raw materials), and phosphoric acid solution and aluminum dihydrogen phosphate solution as composite activators (aluminum dihydrogen phosphate accounts for 10%, 20%, 30%, 40% and 50% of the weight of activator).
[0031] Figure 6 The coagulation time diagram of the aluminum phosphate silicate inorganic polymer when W / S = 0.8, with metakaolin and activated calcium oxide as precursor raw materials (activated calcium oxide accounts for 8% of the weight of the precursor raw materials), and phosphoric acid solution and aluminum dihydrogen phosphate solution as composite activators (aluminum dihydrogen phosphate accounts for 10%, 20%, 30%, 40% and 50% of the weight of the activator). Detailed Implementation
[0032] This invention provides an inorganic polymer of phosphoaluminosilicate, comprising the following raw materials in parts by weight:
[0033] 50-67 parts of precursor raw material, 33-50 parts of activator, and water;
[0034] The precursor raw materials include metakaolin and activated calcium oxide;
[0035] The active calcium oxide accounts for 3 to 15% of the weight of the precursor raw material;
[0036] The activator comprises a phosphoric acid solution.
[0037] Unless otherwise specified, all raw materials used in this invention are preferably commercially available products.
[0038] The raw materials for preparing the phosphoaluminosilicate inorganic polymer provided by this invention include 50-67 parts by weight of precursor raw materials, preferably 55-60 parts. In this invention, the precursor raw materials include metakaolin and activated calcium oxide. In this invention, the activated calcium oxide is preferably obtained by calcining limestone; the calcination temperature is preferably 850-1250℃, more preferably 1000-1100℃, and even more preferably 1050℃; the holding time is preferably 4 hours. In this invention, the particle size of the metakaolin is preferably D. 95 ≤40μm, D 50 ≤12μm. In this invention, the preferred particle size of the activated calcium oxide is: D 95 ≤40μm, D 50 ≤12μm. In this invention, the active calcium oxide accounts for 3-15% of the weight of the precursor raw material, preferably 6-9%.
[0039] Based on the weight parts of the precursor raw materials, the raw materials for preparing the aluminum phosphate silicate inorganic polymer provided by the present invention include 33 to 50 parts by weight of an activator. In the present invention, the activator comprises a phosphoric acid solution, preferably with a mass content of 85%. In the present invention, the activator preferably further comprises an aluminum dihydrogen phosphate solution, preferably comprising 0 to 70% of the weight of the activator, and not 0%, more preferably 10 to 50%, and more preferably 10 to 30%. In the present invention, the molar ratio of H3PO4 to Al(OH)3 in the aluminum dihydrogen phosphate solution is preferably 3.2:1. In the present invention, the aluminum dihydrogen phosphate solution preferably comprises the following raw materials in parts by weight: 13 parts aluminum hydroxide powder, 61.5 parts of an 85% phosphoric acid solution, and 25.5 parts water.
[0040] In this invention, the preparation method of the aluminum dihydrogen phosphate solution preferably includes the following steps: mixing aluminum hydroxide powder and water to obtain an aluminum hydroxide solution; mixing the aluminum hydroxide solution and phosphoric acid, and stirring to obtain the aluminum dihydrogen phosphate solution. In this invention, the mixing temperature of the aluminum hydroxide powder and water is preferably 85°C. In this invention, the mixing of aluminum hydroxide powder and water preferably includes: heating the water and then adding the aluminum hydroxide powder; the heating temperature is preferably 85°C. In this invention, the mixing temperature of the aluminum hydroxide solution and phosphoric acid is preferably 85°C. In this invention, the mixing of the aluminum hydroxide solution and phosphoric acid preferably includes: heating the phosphoric acid and then adding the aluminum hydroxide solution; the heating temperature is preferably 85°C; the heating is preferably carried out under water bath conditions. In this invention, the stirring time is preferably 30 min, and the stirring speed is preferably 30–50 rpm.
[0041] The raw materials for preparing the phosphoaluminosilicate inorganic polymer provided by this invention include water.
[0042] In this invention, the liquid-to-solid mass ratio (W / S) of the raw materials for preparing the phosphoaluminosilicate inorganic polymer is preferably 0.5–1.2:1, more preferably 0.6–0.9:1, and even more preferably 0.7–0.8:1. In this invention, the liquid is water and water contained in the activator. In this invention, the solid is a precursor raw material.
[0043] This invention also provides a method for preparing the phosphoroaluminosilicate inorganic polymer described in the above technical solution, comprising the following steps:
[0044] The activator and water are mixed to obtain a liquid.
[0045] The precursor raw material and liquid are mixed, and the resulting slurry is cured to obtain the phosphoroaluminosilicate inorganic polymer.
[0046] This invention mixes an activator with water to obtain a liquid.
[0047] The present invention does not impose specific limitations on the mixing method of the activator and water, as long as the two can be mixed evenly.
[0048] After obtaining the liquid material, the present invention mixes the precursor raw material and the liquid material to obtain a slurry and cures it to obtain the phosphoroaluminosilicate inorganic polymer.
[0049] In this invention, the mixing of the precursor raw material and the liquid material preferably includes slow stirring and fast stirring in sequence. The speed of slow stirring is preferably 135-145 rpm and the time is preferably 6 min. The speed of fast stirring is preferably 275-295 rpm and the time is preferably 6 min.
[0050] In this invention, the slurry is preferably further subjected to molding before curing. The molding is preferably carried out in a mold. In a specific embodiment of this invention, the size of the mold is preferably 40mm×40mm×40mm.
[0051] In this invention, the maintenance regime is preferably standard maintenance, wherein the humidity of the standard maintenance is preferably >95%, the temperature is preferably 20±2℃, and the maintenance period is preferably 7 to 60 days.
[0052] This invention also provides the application of the phosphoroaluminate silicate inorganic polymer described in the above technical solution or the phosphoroaluminate silicate inorganic polymer prepared by the preparation method described in the above technical solution in the construction of high-level radioactive waste geological disposal repositories.
[0053] This invention does not specifically limit the application of the aforementioned phosphosaluminosilicate inorganic polymer in the construction of high-level radioactive waste geological repositories; those skilled in the art can make settings according to actual needs.
[0054] The following detailed description, in conjunction with embodiments, illustrates the phosphosaluminosilicate inorganic polymer, its preparation method, and its applications provided by the present invention. However, these descriptions should not be construed as limiting the scope of protection of the present invention.
[0055] Example 1
[0056] An inorganic polymer of phosphosilicate comprises the following raw materials in parts by weight:
[0057] The precursor consisted of 50.7 parts metakaolin, 5 parts activated calcium oxide, and 44.3 parts phosphoric acid solution with a mass content of 85%, wherein the W / S ratio was 0.8 and the activated calcium oxide accounted for 9% of the weight of the precursor raw materials.
[0058] The method for preparing activated calcium oxide is as follows: limestone is calcined at 1050℃ for 4 hours.
[0059] The preparation method of phosphosaluminosilicate inorganic polymer is as follows:
[0060] Metakaolin and activated calcium oxide were mixed to obtain a powder; phosphoric acid solution and water were mixed to obtain a liquid; the powder and liquid were mixed and stirred at 140 rpm for 6 min, and then stirred at 285 rpm for 6 min to obtain a slurry; the slurry was injected into a 40 mm × 40 mm × 40 mm mold, and the resulting stone was cured for 7 to 60 days under conditions of humidity > 95% and temperature of 20 ± 2℃ to obtain an inorganic polymer of phosphoroaluminosilicate.
[0061] The fluidity of the obtained phosphoroaluminate silicate inorganic polymer slurry was 310 mm. The compressive strength of the aggregate at 7 days, 14 days and 28 days was measured to be 14.4 MPa, 17.6 MPa and 28.5 MPa, respectively, according to the "Test Method for Strength of Cement Mortar" (GB / T 17671-1999). The initial setting time and final setting time of the phosphoroaluminate silicate inorganic polymer were determined to be 67 h and 78 h, respectively, according to the "Test Method for Standard Consistency Water Requirement, Setting Time and Soundness of Cement" (GB / T1346).
[0062] Example 2
[0063] An inorganic polymer of phosphosilicate comprises the following raw materials in parts by weight:
[0064] The mixture consists of 51.2 parts metakaolin, 4.5 parts activated calcium oxide, 35.4 parts phosphoric acid solution with a mass content of 85%, and 8.9 parts aluminum dihydrogen phosphate solution, with a W / S ratio of 0.8. The activated calcium oxide accounts for 8% of the weight of the precursor raw materials, and the aluminum dihydrogen phosphate solution accounts for 20% of the weight of the activator.
[0065] The preparation method of activated calcium oxide is the same as in Example 1.
[0066] The preparation method of aluminum dihydrogen phosphate solution is as follows: Step 1: According to the experimental ratio, weigh 61.5 parts by weight of phosphoric acid solution (mass content of 85%) and pour it into a beaker. Place the beaker in a water bath and heat it to 85°C. At the same time, weigh 25.5 parts by weight of water and 13 parts by weight of aluminum hydroxide powder. Pour the water into a beaker and place it in a temperature-controlled magnetic stirrer. Set the temperature to 85°C, and then pour the weighed aluminum hydroxide powder into the beaker at a uniform speed. Step 2: Pour the uniformly heated phosphoric acid obtained in Step 1 into the temperature-controlled magnetic stirrer, and gradually add the uniformly stirred aluminum hydroxide solution obtained in Step 1. Step 3: Stir the solution obtained in Step 2 for 30 minutes to obtain a clear and transparent aluminum dihydrogen phosphate solution.
[0067] The preparation method of phosphosaluminosilicate inorganic polymer is as follows:
[0068] Metakaolin and activated calcium oxide were mixed to obtain a powder; phosphoric acid solution, aluminum dihydrogen phosphate solution and water were mixed to obtain a liquid; the powder and liquid were mixed and stirred at 140 rpm for 6 min, and then stirred at 285 rpm for 6 min to obtain a slurry; the slurry was injected into a 40 mm × 40 mm × 40 mm mold, and the resulting stone body was placed under conditions of humidity > 95% and temperature of 20 ± 2℃ for 7 to 60 days to obtain an inorganic polymer of aluminum phosphate silicate.
[0069] The slurry fluidity of the phosphoroaluminate silicate inorganic polymer is 345 mm. The compressive strength of the aggregate at 7 days, 14 days, and 28 days of curing, as measured by GB / T 17671-1999, is 18.0 MPa, 27.3 MPa, and 30.2 MPa, respectively. The initial and final setting times of the phosphoroaluminate silicate inorganic polymer, as determined by GB / T1346, are 34 h and 37 h, respectively.
[0070] Example 3
[0071] An inorganic polymer of phosphosilicate comprises the following raw materials in parts by weight:
[0072] The precursor consisted of 51.2 parts metakaolin, 4.5 parts activated calcium oxide, and 44.3 parts phosphoric acid solution with a mass content of 85%, wherein the W / S ratio was 0.8 and the activated calcium oxide accounted for 8% of the weight of the precursor raw materials.
[0073] The preparation method of the phosphoroaluminosilicate inorganic polymer is the same as in Example 1.
[0074] The fluidity of the obtained phosphoroaluminate silicate inorganic polymer slurry was 290 mm. The compressive strength of the aggregate at 7 days, 14 days and 28 days of curing was measured to be 17.6, 29.1 and 28.8 MPa, respectively, according to the "Test Method for Strength of Cement Mortar" (GB / T 17671-1999). The initial setting time and final setting time of the phosphoroaluminate silicate inorganic polymer were determined to be 35 h and 41 h, respectively, according to the "Test Method for Standard Consistency Water Requirement, Setting Time and Soundness of Cement" (GB / T1346).
[0075] Example 4
[0076] An inorganic polymer of phosphosilicate comprises the following raw materials in parts by weight:
[0077] The mixture consisted of 51.2 parts metakaolin, 4.5 parts activated calcium oxide, 35.4 parts phosphoric acid solution with a mass content of 85%, and 8.9 parts aluminum dihydrogen phosphate solution, with a W / S ratio of 0.8. The activated calcium oxide accounted for 8% of the weight of the precursor raw materials, and the aluminum dihydrogen phosphate solution accounted for 10% of the weight of the activator.
[0078] The preparation method of the phosphoroaluminosilicate inorganic polymer is the same as in Example 2.
[0079] The fluidity of the obtained phosphoroaluminate silicate inorganic polymer slurry was 345 mm. According to the "Test Method for Strength of Cement Mortar" (GB / T 17671-1999), the compressive strength of the aggregate at 7 days, 14 days and 28 days of curing was 18.0, 27.3 and 30.2 MPa, respectively. Referring to the "Test Method for Standard Consistency Water Requirement, Setting Time and Soundness of Cement" (GB / T1346), the initial setting time and final setting time of the phosphoroaluminate silicate inorganic polymer were determined to be 21 h and 24 h, respectively.
[0080] Comparative Example 1
[0081] The inorganic polymer of phosphoaluminosilicate comprises the following raw materials in parts by weight:
[0082] 56 parts of metakaolin and 44 parts of phosphoric acid solution with a mass content of 85% were used, where W / S = 0.8.
[0083] The fluidity of the obtained phosphoaluminosilicate inorganic polymer slurry was 260 mm. Referring to the "Test Method for Strength of Cement Mortar" (GB / T 17671-1999), the compressive strengths of the aggregate at 7 days, 14 days, and 28 days of curing were measured to be 0 MPa, 5.4 MPa, and 7.8 MPa, respectively. Referring to the "Test Method for Standard Consistency Water Requirement, Setting Time and Soundness of Cement" (GB / T1346), the initial setting and final setting times of the phosphoaluminosilicate inorganic polymer were determined to be 126 h and 233 h, respectively.
[0084] Comparative Example 2
[0085] An inorganic polymer of phosphosilicate comprises the following raw materials in parts by weight:
[0086] The mixture consisted of 56 parts metakaolin, 35 parts phosphoric acid solution with a mass content of 85%, and 9 parts aluminum dihydrogen phosphate solution, with a W / S ratio of 0.8. The aluminum dihydrogen phosphate solution accounted for 20% of the weight of the activator.
[0087] The fluidity of the obtained phosphoaluminosilicate inorganic polymer slurry was 295 mm. The compressive strengths of the aggregate at 7 days, 14 days, and 28 days were measured to be 0 MPa, 13.8 MPa, and 21.0 MPa, respectively, according to the "Test Method for Strength of Cement Mortar" (GB / T 17671-1999). The initial and final setting times of the phosphoaluminosilicate inorganic polymer were determined to be 133 h and 159 h, respectively, according to the "Test Method for Standard Consistency Water Requirement, Setting Time and Soundness of Cement" (GB / T1346).
[0088] Figure 1The compressive strength diagram of the phosphorus aluminum silicate inorganic polymer is shown when W / S = 0.8, using metakaolin and activated calcium oxide as precursor raw materials (activated calcium oxide accounts for 3%, 6%, 9%, 12%, and 15% of the weight of the precursor raw materials), and phosphoric acid solution as the activator. Figure 1 It is known that replacing metakaolin with activated calcium oxide in a certain proportion can effectively improve the compressive strength of phosphoaluminosilicate inorganic polymers, and the compressive strength increases with the increase of the proportion of activated calcium oxide. When activated calcium oxide replaces 15% of metakaolin, the compressive strength of the inorganic polymer after standard curing for 14, 28 and 60 days is as high as 29.9 MPa, 34.9 MPa and 36.1 MPa, respectively. When activated calcium oxide replaces 9% of metakaolin (Example 1), the compressive strength of the phosphoaluminosilicate inorganic polymer after 14, 28 and 60 days is 17.6 MPa, 28.5 MPa and 30.8 MPa, respectively, while the compressive strength of the phosphoaluminosilicate inorganic polymer without activated calcium oxide precursor (Comparative Example 1) after 14, 28 and 60 days is only 5.4 MPa, 7.8 MPa and 7.9 MPa, respectively.
[0089] Figure 2 The flowability diagram of the phosphoaluminosilicate inorganic polymer with W / S = 0.8, using metakaolin and activated calcium oxide as precursor raw materials (activated calcium oxide accounting for 3%, 6%, 9%, 12%, and 15% of the precursor raw material weight), and phosphoric acid solution as the activator. Figure 2 It can be seen that the fluidity of the phosphorus aluminum silicate inorganic polymer slurry first increases and then decreases with the increase of active calcium oxide content. The fluidity of Example 1 is about 19% higher than that of Comparative Example 1.
[0090] Figure 3 The graph shows the coagulation time of the phospha-aluminosilicate inorganic polymer when W / S = 0.8, using metakaolin and activated calcium oxide as precursor raw materials (activated calcium oxide accounting for 3%, 6%, 9%, 12%, and 15% of the precursor raw material weight), and phosphoric acid solution as the activator. Figure 3 It can be seen that the setting time of the phosphoaluminosilicate inorganic polymer gradually decreases with the addition of activated calcium oxide and the increase of the dosage. When activated calcium oxide replaces 15% of metakaolin, the initial setting and final setting times of the phosphoaluminosilicate inorganic polymer are 19 h and 38 h, respectively, while the initial setting and final setting times of the phosphoaluminosilicate inorganic polymer without activated calcium oxide precursor are 126 h and 233 h, respectively.
[0091] Figure 4 The compressive strength of the aluminum phosphate silicate inorganic polymer is shown in the figure when W / S = 0.8, with metakaolin and activated calcium oxide as precursor raw materials (activated calcium oxide accounts for 8% of the weight of the precursor raw materials), and phosphoric acid solution and aluminum dihydrogen phosphate solution as composite activators (aluminum dihydrogen phosphate accounts for 10%, 20%, 30%, 40% and 50% of the weight of the activator).
[0092] Figure 5 The flowability diagram of the aluminum phosphate silicate inorganic polymer when W / S = 0.8, with metakaolin and activated calcium oxide as precursor raw materials (activated calcium oxide accounts for 8% of the weight of the precursor raw materials), and phosphoric acid solution and aluminum dihydrogen phosphate solution as composite activators (aluminum dihydrogen phosphate accounts for 10%, 20%, 30%, 40% and 50% of the weight of the activator).
[0093] Figure 6 The graph shows the setting time of the aluminum phosphate silicate inorganic polymer when W / S = 0.8, using metakaolin and activated calcium oxide as precursor raw materials (activated calcium oxide accounts for 8% of the precursor raw material weight), and phosphoric acid solution and aluminum dihydrogen phosphate solution as composite activators (aluminum dihydrogen phosphate accounts for 10%, 20%, 30%, 40%, and 50% of the activator weight). Figure 4 , Figure 5 and Figure 6 It can be seen that, compared with the phosphoric acid solution and aluminum dihydrogen phosphate solution as activators, the compressive strength of the phosphoric acid silicate inorganic polymer with metakaolin and activated calcium oxide precursors is significantly improved, the workability of the phosphoric acid silicate inorganic polymer slurry is significantly improved, and the setting time of the phosphoric acid silicate inorganic polymer is significantly reduced.
[0094] according to Figures 1-6 The measurement results and the specific test results of Examples 1-4 and Comparative Examples 1-2 show that:
[0095] (1) For Example 1, compared with Comparative Example 1, W / S = 0.8, all activators were 85% phosphoric acid solution, W / S = 0.8 remained unchanged, only 9% of metakaolin in the precursor material was replaced by active calcium oxide, and the compressive strength of the phosphoaluminosilicate inorganic polymer at 7 days, 14 days and 28 days increased from 0 MPa, 5.4 MPa and 7.8 MPa to 14.4 MPa, 17.6 MPa and 28.5 MPa, respectively, the fluidity increased from 260 mm to 310 mm, and the initial setting time and final setting time decreased from 126 h and 233 h to 67 h and 78 h, respectively.
[0096] (2) For Example 2, compared with Comparative Example 2, the amount and ratio of phosphoric acid solution and aluminum dihydrogen phosphate in the activator (aluminum dihydrogen phosphate accounts for 20% of the activator mass) remained unchanged, W / S = 0.8 remained unchanged, only 8% of the precursor metakaolin mass was replaced by active calcium oxide, and the strength of the phosphoaluminosilicate inorganic polymer at 7 days, 14 days and 28 days increased from 0 MPa, 13.8 MPa and 21.0 MPa to 18.0 MPa, 27.3 and 30.2 MPa, respectively, the fluidity increased from 295 mm to 345 mm, and the initial setting time and final setting time decreased from 133 h and 159 h to 34 h and 37 h, respectively.
[0097] (3) For Example 3, compared with Comparative Example 1, the activator was all phosphoric acid solution with a mass content of 85%, and the W / S = 0.8 remained unchanged. Only 8% of the metakaolin in the precursor material was replaced by active calcium oxide. The compressive strength of the phosphoaluminosilicate inorganic polymer at 7 days, 14 days and 28 days increased from 0 MPa, 5.4 MPa and 7.8 MPa to 17.6 MPa, 29.1 MPa and 28.8 MPa, respectively. The fluidity increased from 250 mm to 270 mm. The initial setting time and final setting time decreased from 126 h and 233 h to 72 h and 78 h, respectively.
[0098] (4) For Example 4, compared with Example 3, the composition of the precursor (8% of metakaolin in the precursor material was replaced by activated calcium oxide) remained unchanged, W / S = 0.8 remained unchanged, only the 85% phosphoric acid solution in the activator was replaced by 10% aluminum dihydrogen phosphate. The compressive strength of the phosphoaluminosilicate inorganic polymer at 7 days, 14 days and 28 days differed by 0.2 MPa, 1.0 MPa and 1.8 MPa respectively (within the normal deviation range), the fluidity increased from 290 mm to 345 mm, and the initial setting time and final setting time were shortened from 72 h and 78 h to 21 h and 24 h respectively.
[0099] 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 phosphorus aluminum silicate inorganic polymer, characterized in that, The preparation materials include the following parts by weight: The mixture contains 51.2 parts metakaolin, 4.5 parts activated calcium oxide, and 44.3 parts activator. The activator comprises a phosphoric acid solution and an aluminum dihydrogen phosphate solution with a mass content of 85%, wherein the aluminum dihydrogen phosphate solution accounts for 10% of the weight of the activator, and water. In the raw materials for preparing the phosphoroaluminosilicate inorganic polymer, the mass ratio of liquid to solid is 0.8:1; the liquid is water and the water contained in the activator; the solid is the precursor raw material. The aluminum dihydrogen phosphate solution comprises the following raw materials in parts by weight: 13 parts aluminum hydroxide powder, 61.5 parts phosphoric acid solution with a mass content of 85%, and 25.5 parts water.
2. The phosphoroaluminosilicate inorganic polymer according to claim 1, characterized in that, The active calcium oxide is obtained by calcining limestone at a temperature of 850~1250℃ and a holding time of 4h.
3. The method for preparing the phosphoroaluminosilicate inorganic polymer according to any one of claims 1 to 2, characterized in that, Includes the following steps: The activator and water are mixed to obtain a liquid. The precursor raw material and liquid are mixed, and the resulting slurry is cured to obtain the phosphoroaluminosilicate inorganic polymer.
4. The preparation method according to claim 3, characterized in that, The maintenance regime is standard maintenance, with humidity >95%, temperature 20±2℃, and maintenance period of 7~60 days.
5. The application of the phosphoroaluminosilicate inorganic polymer according to any one of claims 1 to 2 or the phosphoroaluminosilicate inorganic polymer prepared by the preparation method according to any one of claims 3 to 4 in the construction of a high-level radioactive waste geological disposal site.