Geopolymer-based curing agent, auxiliary agent and application method of geopolymer-based curing agent

Abstract

The invention relates to the technical field of geopolymer materials, in particular to a geopolymer-based curing agent, an auxiliary agent and an application method of the geopolymer-based curing agent. The geopolymer-based curing agent aid comprises the following raw material components in percentage by mass: 40%-50% of aromatic hydroxyl multi-base polymer, 10%-15% of sodium persulfate, 15%-20% of calcium oxide, 10%-15% of magnesium oxide and 10%-15% of potassium sulfate. The geopolymer-based curing agent comprises the following raw material components in percentage by mass: 45%-55% of waste slag powder, 25%-35% of Portland cement, 15%-25% of an alkali activator and 3%-6% of an auxiliary agent. The improved additive based on the aromatic hydroxyl multi-group polymer is used in the curing agent, so that the comprehensive performance of the geopolymer-based curing agent is optimized, the curing efficiency, the mechanical property and the durability are improved, and the geopolymer-based curing agent is suitable for resource utilization of building materials, residual mud and waste slag.

Description

Technical Field

[0001] The present invention relates to the technical field of geopolymer materials, and in particular to a geopolymer-based curing agent, an auxiliary agent and an application method thereof. Background Art

[0002] Geopolymers have attracted widespread attention due to their environmental friendliness, high strength, and corrosion resistance. Geopolymer-based curing agents are key to achieving these properties. These curing agents typically consist of waste slag powder, Portland cement, and an alkali activator. However, existing geopolymer-based curing agents still have room for improvement in curing efficiency, durability, and mechanical properties, particularly due to their poor adaptability to diverse waste streams, such as multi-source residual sludge and slag.

[0003] Specifically, existing geopolymer-based curing agents have the following technical problems: (1) Low curing efficiency. Existing geopolymer-based curing agents typically rely on a mixed reaction of waste slag powder, Portland cement, and an alkali activator. However, due to the low chemical activity of these components, the curing reaction rate is slow, especially in low-temperature environments, and the curing time is long, which cannot meet the requirements of rapid construction or efficient production of residual mud and soil curing projects.

[0004] (2) Insufficient mechanical properties. The solidified body formed by existing geopolymer curing agents has low strength in the early curing stage, which may cause problems such as shrinkage and cracking. In addition, in high temperature or humid environments, the compressive strength and flexural properties of the solidified body are easily reduced, affecting the long-term stability of the material.

[0005] (3) Poor chemical corrosion resistance. Geopolymer materials may experience structural degradation in strong acid, strong alkali or salt solutions, resulting in poor chemical corrosion resistance, which limits their application in highly corrosive environments.

[0006] (4) Poor adaptability to industrial by-products. The chemical properties of waste slag, industrial waste alkali or silicate components from different sources vary greatly. Existing technologies make it difficult to specifically adjust the curing agent formula to adapt to diverse raw materials, which limits the efficient utilization of waste resources.

[0007] (5) Insufficient microstructure optimization. In the reaction system of existing geopolymer curing agents, the microstructure of the cured body is relatively loose, resulting in a high porosity of the material, which affects its density, crack resistance and long-term durability. Summary of the Invention

[0008] The present invention provides a geopolymer-based curing agent, an auxiliary agent and an application method thereof, aiming to improve the curing efficiency, compressive strength and long-term stability of the geopolymer-based curing agent by optimizing the formula design and the synergistic effect of the components.

[0009] The invention provides a geopolymer-based curing agent auxiliary, comprising raw material components composed in the following mass percentages: 40% to 50% of an aromatic hydroxyl multi-base polymer, 10% to 15% of sodium persulfate, 15% to 20% of calcium oxide, 10% to 15% of magnesium oxide, and 10% to 15% of potassium sulfate.

[0010] As a further improvement of the present invention, the aromatic hydroxyl multi-radical polymer has an aromatic ring as the core, and contains active groups in the molecular structure: carboxyl, alcoholic hydroxyl, phenolic hydroxyl, methoxy and carbonyl, wherein the active groups are composed according to the following mass percentages: phenolic hydroxyl 30%~40%, carboxyl 20%~30%, alcoholic hydroxyl 10%~20%, methoxy 5%~15%, and carbonyl 5%~10%.

[0011] The present invention also provides a geopolymer-based curing agent, comprising raw material components composed in the following mass percentages: 45% to 55% of waste slag powder, 25% to 35% of Portland cement, 15% to 25% of an alkali activator, and 3% to 6% of the geopolymer-based curing agent additive as claimed in claim 1 or 2.

[0012] As a further improvement of the present invention, the alkali activator comprises one or more of the following components: water glass, industrial waste alkali; When the alkaline activator includes multiple components, the mass percentage of each component in different cases is as follows: High-silicon system combination based on water glass: 50%~60% water glass, 20%~30% industrial waste alkali; An economical combination based on solid alkali: industrial waste alkali 40%~50%, water glass 10%~20%; Balanced combination: water glass 30%~40%, industrial waste alkali 20%~30%.

[0013] The present invention also provides an application method of a geopolymer-based curing agent auxiliary, comprising the following steps: a1. The aromatic hydroxyl multi-radical polymer is used as the core component, and other inorganic components are added according to the designed proportions. The mass percentages of the added components are: aromatic hydroxyl multi-radical polymer 40%~50%, sodium persulfate 10%~15%, calcium oxide 15%~20%, magnesium oxide 10%~15%, and potassium sulfate 10%~15%; a2. Store the mixed additives in a sealed container for later use.

[0014] As a further improvement of the present invention, in step a1, the preparation process of the aromatic hydroxyl multi-radical polymer includes: a11. Raw material selection: The raw material components are composed of the following percentages by mass: 35-45% phenol, 25-30% p-carboxybenzoic acid, 10-15% methanol, and 5-10% benzaldehyde; a12 esterification reaction: Phenol and p-carboxybenzoic acid were mixed, followed by the addition of concentrated sulfuric acid as a catalyst, and the reaction was heated at 120 ° C for 2 hours to obtain a phenol ester intermediate; a13 etherification reaction: The generated phenol ester intermediate was mixed with methanol, aluminum chloride was added as a catalyst, and heated at 150 ° C for 4 hours to carry out etherification reaction to obtain a methoxy-containing intermediate; a14 oxidation reaction: benzaldehyde was added to the methoxy-containing intermediate, 6ml of 30% hydrogen peroxide was added for oxidation to generate a carbonyl group, the reaction temperature was controlled at 80 ° C, the reaction was allowed to proceed for 1 hour to obtain a carbonyl-containing intermediate; a15. Polymerization reaction: The obtained carbonyl-containing intermediate is diluted with dichloromethane solvent, aluminum chloride is added as a polymerization catalyst, and then heated to 180 ° C. The reaction is maintained for 12 hours to complete the polymerization reaction. After the reaction is completed, it is cooled to room temperature; finally, the polymer is washed to remove unreacted monomer and catalyst, and the solvent is removed by rotary evaporation or vacuum drying to obtain an aromatic hydroxyl multi-base polymer.

[0015] The present invention also provides an application method of a geopolymer-based curing agent, comprising the following steps: b1. Preparation and pretreatment of curing agent raw materials: The waste slag powder is sieved to ensure uniform particle distribution. The alkali activator is prepared by mixing one or more components of water glass, silicate, and industrial waste alkali. Standard specifications of Portland cement are selected; b2 improved additive preparation: According to the application method of the geopolymer-based curing agent additive prepared; b3. Mixing process: Add 45% to 55% by mass of waste slag powder, 25% to 35% by mass of Portland cement, and 15% to 25% by mass of alkali activator into a mixer and mix well. Then add 3% to 6% by mass of additives and mix well to obtain a uniform slurry.

[0016] As a further improvement of the present invention, in step b3, before adding the auxiliary agent in the curing process, the following operations are performed on the auxiliary agent: Use a mechanical stirrer to mix in two stages: low speed mixing in the first stage to achieve initial uniformity, and medium speed mixing in the second stage to achieve full dispersion.

[0017] As a further improvement of the present invention, in step b3, the two-stage mixing method of the auxiliary agent is divided into the following situations: Case 1: Direct transition method: Immediately after the low-speed mixing stage, the speed is gradually increased to the medium-speed stage; Case 2: If incompletely dispersed particles or uneven mixing occur during the mixing process, pause and perform scraping operations after the low-speed mixing stage, and then enter the medium-speed mixing stage; Case 3: If on-site conditions permit, temporarily mix all the components of the additive before use. The recommended order of addition is: first, fully stir the aromatic hydroxyl multi-polymer, calcium oxide, magnesium oxide, and potassium sulfate into a mixture at a low-speed mixing stage; second, add sodium persulfate alone to the mixture at a medium-speed mixing stage and fully stir.

[0018] As a further improvement of the present invention, step b3 includes the following two application methods: b31. The waste slag powder, Portland cement, alkali activator and the material to be solidified are uniformly mixed to obtain a mixed slurry, and the moisture content is controlled at 50~80% during the process; b32. Mix the waste slag powder, Portland cement and alkali activator evenly to prepare a geopolymer mixed slurry. The water-cement ratio can be controlled at 0.3~0.5 during the process.

[0019] As a further improvement of the present invention, the method for applying the geopolymer-based curing agent further comprises the steps of: b4. Mold forming: Select a mold, pour the mixed slurry into the mold, and vibrate the mold to remove bubbles in the slurry; b5. Project site pouring: pour the mixed slurry into the designated location on the project site; b6. Curing: The slurry is left to solidify under natural conditions to obtain a solidified body, which is then covered or cured according to indoor and on-site conditions.

[0020] The beneficial effects of the present invention are: by using an improved additive based on aromatic hydroxyl multi-base polymer in a curing agent, the comprehensive performance of the geopolymer-based curing agent is optimized, the curing efficiency, mechanical properties and durability are improved, and it is suitable for the resource utilization of building materials, residual mud and waste slag. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below with reference to the embodiments.

[0022] The present invention relates to a geopolymer-based curing agent improvement additive based on aromatic hydroxyl multi-radical polymers and an application method thereof. The technical solution of the present invention includes the following contents.

[0023] (1) The composition ratio of geopolymer-based curing agent and improvement auxiliary agent based on aromatic hydroxyl multi-polymer.

[0024] (1) Composition of geopolymer-based curing agent: The geopolymer-based curing agent is composed of the following mass percentage ranges: waste slag powder 45% to 55%, silicate cement 25% to 35%, and alkali activator: 15% to 25%.

[0025] The alkali activator includes one or more of the following components: water glass (sodium silicate solution); industrial waste alkali (such as sodium hydroxide, potassium hydroxide or alkali-containing waste liquid, calcium carbide slag, etc.).

[0026] Water glass (sodium silicate solution) is used to provide silicon-oxygen tetrahedrons to strengthen the network structure of the geopolymer, while industrial waste alkali (such as sodium hydroxide, potassium hydroxide or alkali-containing waste liquid) provides an alkaline environment to promote the activation of slag and silicates.

[0027] The alkali activator can be optimized according to different application requirements. Specifically, when the alkali activator includes multiple components, the mass percentage of each component in different cases is as follows: Sodium silicate-based (high-silicon system): Suitable for applications requiring higher mechanical properties and compactness. Sodium silicate 50%-60%, industrial waste alkali (sodium hydroxide / potassium hydroxide) 20%-30%.

[0028] Solid alkali-based (economical): Suitable for resource utilization of industrial waste alkali and cost control. Industrial waste alkali 40%~50%, water glass 10%~20%.

[0029] Balanced combination: An optimized design that comprehensively considers performance and cost. Sodium silicate 30%-40%; industrial waste alkali (sodium hydroxide / potassium hydroxide) 20%-30%.

[0030] (2) Composition of improved additives: The modified additive is composed of an aromatic hydroxyl polypolymer as the core, combined with inorganic components and oxidative components. Specifically, it includes: Polyfunctional Hydroxylated Aromatic Polymer (PHAP, 40%-50%): The aromatic ring is the core, and the molecular structure contains active groups such as carboxyl, alcoholic hydroxyl, phenolic hydroxyl, methoxy and carbonyl groups, which can enhance the chemical bonding strength and toughness of the material. The active groups are composed of the following mass percentages: phenolic hydroxyl 30%~40%, carboxyl 20%~30%, alcoholic hydroxyl 10%~20%, methoxy 5%~15%, carbonyl 5%~10%. If the material needs to have particularly strong chemical corrosion resistance, the proportion of carboxyl (-COOH) or carbonyl (C=O) can be increased; if flexibility and aging resistance need to be enhanced, the proportion of methoxy (-OCH3) can be increased. For example [(C 10 H4(OH)2(COOH)(CH2OH)(C=O)(OCH3))] n , [(C6H3(OH)(CH2OH)(COOH)(OCH3))] n etc. Among them [(C 10 H4(OH)2(COOH)(CH2OH)(C=O)(OCH3))]n It is a functionalized phenol polymer. Its basic unit is a benzene ring with the following functional groups: phenolic hydroxyl groups (-OH), which are highly chemically reactive. Carboxyl groups (-COOH) provide polarity and facilitate ion complexation. Alcoholic hydroxyl groups (-CH2OH) enhance crosslinking and polycondensation capabilities. Methoxy groups (-OCH3) improve solubility, enhance material flexibility, and enhance aging resistance. [(C6H3(OH)(CH2OH)(COOH)(OCH3))] n It is a functionalized polymer based on a polycyclic aromatic skeleton. The core unit is a polycyclic aromatic molecule (such as naphthalene or phenanthrene) with the following functional groups: phenolic hydroxyl group (-OH): gives the molecule chemical reactivity; carboxyl group (-COOH): increases polarity and helps ion complexation; alcoholic hydroxyl group (-CH2OH): improves cross-linking and condensation capabilities; carbonyl group (C=O): enhances redox properties; methoxy group (-OCH3): improves solubility, enhances material flexibility and anti-aging properties.

[0031] Sodium persulfate (Na2S2O8, 10%~15%): As an oxidant, it decomposes to generate sulfate radicals (SO4•-), accelerates the polymerization reaction, and improves curing efficiency and chemical corrosion resistance.

[0032] Calcium oxide (CaO, 15%~20%): provides an alkaline environment to promote the curing reaction of geopolymer.

[0033] Magnesium oxide (MgO, 10%~15%): Improves the heat resistance and long-term stability of the cured product.

[0034] Potassium sulfate (K2SO4, 10%~15%): provides sulfate and potassium ions, enhances the ion exchange capacity of the material, and improves the mechanical properties and durability of the cured body.

[0035] (3) Use of additives and curing agents: The recommended addition ratio of the improvement additive is 3% to 6% of the mass of the geopolymer-based curing agent, and it should be used after thorough mixing.

[0036] (2) The application process of geopolymer-based curing agents and additives.

[0037] b1. Preparation and Pretreatment of Curing Agent Raw Materials: Sieve the waste slag powder (recommended 100 mesh) to ensure uniform particle distribution. Use Portland cement directly according to specifications without additional treatment. The alkali activator is prepared by mixing one or more of water glass, silicate, and industrial waste alkali in appropriate proportions to ensure alkali activating properties. The components required for the modified additive (PHAP, sodium persulfate, calcium oxide, magnesium oxide, and potassium sulfate) must meet experimental requirements for purity.

[0038] b2. Preparation of improved additives: a1. Take aromatic hydroxyl multi-radical polymer as the core component and add other inorganic components in sequence according to the designed proportions. The mass percentages of the added components are: aromatic hydroxyl multi-radical polymer 40%-50%, sodium persulfate 10%-15%, calcium oxide 15%-20%, magnesium oxide 10%-15%, and potassium sulfate 10%-15%.

[0039] a2. After all components are mixed evenly, store the mixed additives in a sealed container to avoid moisture and contamination. Pre-mixing additives allows for pre-mixing of some components under dry, sealed conditions. However, ingredients that are prone to ineffectiveness (such as sodium persulfate) must be stored separately or added temporarily.

[0040] Preparation process of aromatic hydroxyl polypolymers a11. Raw material selection: Phenol (C6H5OH): provides phenolic hydroxyl groups, with an addition ratio of 35-45%; p-Carboxybenzoic acid (C6H4(CO2H)): provides carboxyl groups, with an addition ratio of 25-30%; Methanol (CH3OH): provides alcoholic hydroxyl groups, which can be converted into methoxy groups (–OCH3) in subsequent reactions. The addition ratio is 10~15%; Benzaldehyde (C6H5CHO): provides carbonyl groups, and the addition ratio is 5~10%.

[0041] The following is an example of preparing 75g of aromatic hydroxyl multi-polymer a12. Esterification reaction: 30 g of phenol and 20 g of carboxybenzoic acid were mixed, and then 2 g of concentrated sulfuric acid was added as a catalyst. The mixture was heated at 120° C. for 2 hours to obtain a phenol ester intermediate.

[0042] a13. Etherification reaction: The generated esterification product was mixed with 10 g of methanol, 2 g of aluminum chloride was added as a catalyst, and the mixture was heated at 150° C. for 4 hours to carry out an etherification reaction to obtain a methoxy-containing intermediate.

[0043] a14. Oxidation reaction: Add 5g of benzaldehyde to the methoxy-containing intermediate, and add 6ml of 30% hydrogen peroxide (H2O2) for oxidation reaction to generate a carbonyl (-C=O) group. Control the reaction temperature to 80°C and react for 1 hour to obtain the carbonyl-containing intermediate.

[0044] a15.Polymerization reaction: The obtained carbonyl-containing intermediate is diluted with 100 ml of dichloromethane solvent. 2 g of aluminum chloride is added as a polymerization catalyst. The reaction is then heated to 180° C. and maintained for 12 hours to complete the polymerization reaction. After completion of the reaction, the mixture is cooled to room temperature. Finally, the polymer is washed to remove unreacted monomer and catalyst. The solvent is removed by rotary evaporation or vacuum drying to obtain an aromatic hydroxyl polyradical polymer.

[0045] b3. Mixed processing: For geopolymer-based curing agent components, add 45%-55% by weight of waste slag powder, 25%-35% by weight of Portland cement, and 15%-25% by weight of an alkali activator to a mixer. Mix thoroughly with the material to be cured (such as residual mud and slag) to create a mixed slurry. Alternatively, the geopolymer slurry can be prepared without the solidified material. After mixing thoroughly, add 3%-6% of a modifying agent and stir until a uniform slurry is formed. The mixing time should be controlled at approximately 5-10 minutes. For easier mixing and to achieve target performance, the water-cement ratio for a single geopolymer solidified body can be controlled between 0.3 and 0.5. For solidified materials such as residual mud and slag, a moisture content of 50-80% is recommended.

[0046] During the curing process, the additives are mixed in two stages using a mechanical stirrer before addition: the first stage is low-speed mixing for 5 minutes to ensure initial uniformity, and the second stage is medium-speed mixing for 10 minutes to achieve full dispersion. The transition between the two stages can be divided into the following situations: The direct transition method is preferred: immediately increase the speed to medium speed after the low-speed mixing is completed without pausing to ensure mixing efficiency. If incompletely dispersed particles or uneven mixing are found during the experiment, after the low-speed mixing stage, you can pause appropriately and perform scraping or other auxiliary operations before entering the medium-speed mixing stage. If site conditions permit, it is recommended to temporarily mix all components of the additive before use to ensure activity. The recommended order of addition is: Step 1: Add aromatic hydroxyl multi-base polymers and their mixtures with inorganic components to the geopolymer-based curing agent; Step 2: Sodium persulfate is added last in the medium-speed mixing stage to ensure that its oxidizing ability is maximized.

[0047] b4.Mold forming: Pour the mixed slurry into a cylindrical mold with a diameter of 39.1 mm and a height of 80 mm. This cylindrical mold is used for standardized experimental performance testing and does not define the shape of the final product. In practical applications, the shape and size of the cured material can be flexibly adjusted to meet specific needs, providing a wide range of applicability. Vibrate the mold for 3 minutes to remove any bubbles in the slurry and ensure a dense molded body.

[0048] b5. Project site pouring: pour the mixed slurry into the designated area of ​​the project site; b6. Maintenance: Early curing: The slurry is left to solidify under natural conditions to obtain a solidified body.

[0049] Post-curing: Covering or curing can be carried out according to indoor and on-site conditions. For example, the solidified body can be cured at a humidity of 90% and a temperature of 25°C for 7 to 28 days, and the curing time can be adjusted according to the test requirements.

[0050] b7. Performance test: Curing rate: The curing rate is observed by testing the unconfined compressive strength after 24 hours of early curing and comparing the curing strength.

[0051] Unconfined compressive strength test: Use a compressive strength testing machine to test the unconfined compressive strength at 7 days and 28 days of curing age.

[0052] Chemical corrosion resistance test: The solidified body with a curing age of 28 days was immersed in a strong acid solution with a pH of 1. The strength retention rate was measured after immersion for 7 days.

[0053] Hydration heat test: Pour the evenly stirred solidified slurry into a mold, place it in a calorimeter to monitor the temperature change, and record the heat released during the hydration reaction within 24 hours.

[0054] (3) Working mechanism

[0055] (1) Reinforcement effect of aromatic hydroxyl multi-polymers: The multifunctional active groups of the aromatic hydroxyl multi-radical polymer are combined with the silica-alumina skeleton of the geopolymer to significantly improve the chemical stability and strength of the cured body while enhancing its toughness.

[0056] (2) Synergistic effect of sodium persulfate and potassium sulfate: Sodium persulfate decomposes to generate sulfate radicals (SO4•-), which significantly accelerate the formation of silicon-oxygen (Si-O) and aluminum-oxygen (Al-O) bonds in geopolymers, shorten the curing time and enhance the material's resistance to chemical corrosion.

[0057] Potassium sulfate further improves the microstructural density of the solidified body by providing potassium ions and sulfate ions, improves its crack resistance and ion stability, and enhances the material's resistance to chemical corrosion.

[0058] (3) Synergistic effect of inorganic components: Calcium oxide provides an alkaline environment to promote the curing reaction, while magnesium oxide improves the heat resistance and long-term stability of the cured body.

[0059] Compared with traditional curing agents and their additives, the additives of the present invention have the following significant advantages: 1) High curing efficiency: The addition of additives can shorten the curing time by 20%~30%.

[0060] 2) Excellent mechanical properties: The compressive strength of the cured body is increased by 30%~40%, and the bending resistance is greatly improved.

[0061] 3) Enhanced chemical stability: The synergistic effect of potassium sulfate and sodium persulfate significantly improves the acid, alkali and chemical corrosion resistance of the solidified body.

[0062] 4) Environmental protection and economic benefits: By utilizing waste slag and industrial waste alkali, the material cost is reduced, and at the same time, the improved auxiliary agent composition is non-toxic and environmentally friendly, with broad application prospects.

[0063] The application process of the present invention is specifically described below with a comparative example and two embodiments.

[0064] Example 1:

[0065] The ratio of the geopolymer-based curing agent is: 55% of waste slag powder, 25% of silicate cement, and 20% of alkali activator (industrial waste alkali and sodium silicate solid mixed in a ratio of 1:1). In this embodiment, no improving agent is added.

[0066] The detailed steps are as follows: b1. Raw material pretreatment.

[0067] Waste slag powder: Pass through a 100-mesh sieve to ensure uniform particles.

[0068] Portland cement: prepared according to specifications, no additional treatment required.

[0069] Industrial waste alkali: adjust the pH to 10 to ensure the alkali excitation ability; sodium silicate solid: sieve to ensure uniform particles.

[0070] b2. Stir and mix the geopolymer-based curing agent.

[0071] Add waste slag powder, silicate cement and alkali activator into the mixing container in sequence and stir evenly until a uniform slurry is formed.

[0072] b3. Mould filling and vibration compaction.

[0073] Pour the mixed slurry into the standard unconfined compressive strength test mold and vibrate it to expel bubbles to ensure that the slurry is fully dense.

[0074] b4. Casting at the construction site: Pour the mixed slurry into the designated area at the construction site.

[0075] b5. Curing and maintenance.

[0076] Early curing: Leave at room temperature (20°C) for 24 hours.

[0077] Later maintenance: transfer to an environment with a humidity of 90% and a temperature of 25°C for maintenance for 28 days.

[0078] b6.Performance test results.

[0079] Test results: The early-cured unconfined compressive strength of the cured product was approximately 900 kPa, reaching 15.3 MPa after 7 days and 30.7 MPa after 28 days. The cumulative heat of hydration over 24 hours was approximately 350.5 J / g, and the strength retention rate after immersion in a pH 1 strong acid solution for 7 days was approximately 83%.

[0080] Example 2:

[0081] The ratio of geopolymer-based curing agent is: 55% of waste slag powder, 25% of silicate cement, and 20% of alkali activator (industrial waste alkali and sodium silicate solid mixed in a ratio of 1:1).

[0082] The improvement auxiliary agent is added at 3% of the mass of the curing agent, and its composition is: 50% aromatic hydroxyl multi-base polymer, 15% sodium persulfate, 15% calcium oxide, 10% magnesium oxide, and 10% potassium sulfate.

[0083] The detailed steps are as follows: b1. Raw material pretreatment.

[0084] Waste slag powder: Pass through a 100-mesh sieve to ensure uniform particles.

[0085] Portland cement: prepared according to specifications, no additional treatment required.

[0086] Industrial waste alkali: adjust the pH to 10 to ensure the alkali excitation ability; sodium silicate solid: sieve to ensure uniform particles.

[0087] b2. Preparation of improved additives.

[0088] Mixing ratio control: Add aromatic hydroxyl polypolymer, sodium persulfate, calcium oxide, magnesium oxide and potassium sulfate into the mixing container in proportion.

[0089] Mix evenly: Mix in a blender on low speed for 5 minutes, then on medium speed for 10 minutes to ensure even distribution of ingredients.

[0090] Ensure there is no lumps and store in a dry and airtight environment.

[0091] b3. Mixing the geopolymer-based curing agent with the additives.

[0092] Add waste slag powder, Portland cement and alkali activator to the mixing container in sequence. Add the improvement agent at a ratio of 3% and stir evenly until a uniform slurry is formed.

[0093] b4. Mould filling and vibration compaction.

[0094] Pour the mixed slurry into the standard unconfined compressive strength test mold and vibrate it to expel bubbles to ensure that the slurry is fully dense.

[0095] b5. Casting at the construction site: Pour the mixed slurry into the designated area at the construction site.

[0096] b6. Curing and maintenance.

[0097] Early curing: Leave at room temperature (20°C) for 24 hours.

[0098] Later maintenance: transfer to an environment with a humidity of 90% and a temperature of 25°C for maintenance for 28 days.

[0099] b7.Performance test results.

[0100] Test results: The early-stage unconfined compressive strength of the cured product was approximately 1.2 MPa, reaching 18.9 MPa after 7 days and 34.8 MPa after 28 days. The heat of hydration of the cured product after 28 days of curing was approximately 367.3 J / g, and the strength retention rate after immersion in a pH 1 strong acid solution for 7 days was approximately 86%.

[0101] Example 3:

[0102] The ratio of geopolymer-based curing agent is: 55% of waste slag powder, 25% of silicate cement, and 20% of alkali activator (industrial waste alkali and sodium silicate solid mixed in a ratio of 1:1).

[0103] The improvement additive is added at 6% of the mass of the geopolymer-based curing agent, and its composition is: 40% aromatic hydroxyl multi-base polymer, 10% sodium persulfate, 20% calcium oxide, 15% magnesium oxide, and 15% potassium sulfate.

[0104] The detailed steps are as follows: b1. Raw material pretreatment.

[0105] Waste slag powder: Pass through a 100-mesh sieve to ensure uniform particles.

[0106] Portland cement: prepared according to specifications, no additional treatment required.

[0107] Sodium silicate solution: Use a commercial sodium silicate solution with an alkalinity between 8 and 10 and set aside.

[0108] b2. Preparation of improved additives.

[0109] Mixing ratio control: Add aromatic hydroxyl polypolymer, sodium persulfate, calcium oxide, magnesium oxide and potassium sulfate into the mixing container in proportion.

[0110] Mix evenly: Mix in a blender on low speed for 5 minutes, then on medium speed for 10 minutes to ensure even distribution of ingredients.

[0111] Storage: Store in a sealed container in a dry environment to avoid moisture or oxidation.

[0112] b3. Mixing the geopolymer-based curing agent with the additives.

[0113] Add the geopolymer-based curing agent (waste slag powder, Portland cement, and sodium silicate solution) to the mixing vessel in the appropriate mass ratio. Once the mixture is evenly mixed, add the modifying agent at a rate of 6%. Continue stirring for 10 minutes until a uniform slurry is formed.

[0114] b4. Mould filling and vibration compaction.

[0115] Pour the mixed slurry into the standard unconfined compressive strength test mold and vibrate it to expel bubbles to ensure that the slurry is fully dense.

[0116] b5. Casting at the construction site: Pour the mixed slurry into the designated area at the construction site.

[0117] b6. Curing and maintenance.

[0118] Early curing: Let stand at room temperature (20°C) for 24 hours.

[0119] Post-curing: Move to a curing box with a humidity of 90% and a temperature of 25°C for 7 days.

[0120] b7.Performance test results.

[0121] Test results: The early-stage unconfined compressive strength of the cured product was approximately 1.5 MPa, reaching 20.1 MPa after 7 days and 40.2 MPa after 28 days. The heat of hydration of the cured product after 28 days of curing was approximately 390.5 J / g, and the strength retention rate after immersion in a pH 1 strong acid solution for 7 days was approximately 89%.

[0122] Example 1 is used as a comparative example. The geopolymer-based curing agent to which additives are added in Examples 2 and 3 has a shortened early curing time of the cured body, an increased hydration heat, and ultimately an increased unconfined compressive strength, an improved strength retention rate under acid immersion, and an improved durability compared to Example 1.

[0123] The advantages of the geopolymer-based curing agent, auxiliary agent and application method of the present invention are: (1) Synergistic enhancement based on aromatic hydroxyl multi-polymers.

[0124] The present invention innovatively introduces aromatic hydroxyl multi-radical polymers as core auxiliary components. Their unique aromatic ring structure and multiple active groups (such as carboxyl, alcoholic hydroxyl, phenolic hydroxyl, methoxy, carbonyl, etc.) can form strong chemical bonds with the silicon oxide (Si-O) and aluminum oxide (Al-O) skeletons of the geopolymer system, thereby improving the chemical reaction rate and strength of the material and solving the problems of low curing efficiency and insufficient mechanical properties.

[0125] (2) Synergistic effect of potassium sulfate and sodium persulfate.

[0126] Potassium sulfate, a multifunctional inorganic component, provides potassium and sulfate ions, optimizing the ionic balance of the cured product and enhancing its density and durability. Sodium persulfate generates sulfate radicals (SO₄•-), significantly accelerating the curing reaction and shortening the curing time, while also improving the material's resistance to chemical corrosion. The synergistic effect of these two agents addresses the shortcomings of existing curing agents in terms of corrosion resistance and microstructural optimization.

[0127] (3) Multi-dimensional synergistic effect of composite inorganic components.

[0128] This invention innovatively combines inorganic components such as calcium oxide, magnesium oxide, and potassium sulfate to synergistically enhance the material's alkaline-induced reaction: calcium oxide provides an alkaline environment, significantly promoting the polymerization reaction of the geopolymer; magnesium oxide enhances the material's heat resistance and long-term stability; and potassium sulfate optimizes the cured product's crack resistance and chemical stability. This multi-dimensional synergistic effect significantly improves the material's mechanical properties and durability.

[0129] (4) Wide adaptability and environmental protection.

[0130] The additive design of this invention takes into account the diverse characteristics of waste slag and industrial waste alkali. By adjusting the ratio of aromatic hydroxyl multi-radical polymer to inorganic components, it can be adapted to industrial byproducts from different sources, thereby improving the utilization efficiency of waste resources. The additive ingredients are non-toxic and environmentally friendly, meeting the requirements of green manufacturing and sustainable development.

[0131] (5) Microstructure optimization.

[0132] The present invention optimizes the microstructure of the solidified body by introducing a multifunctional additive, reduces porosity, improves material density, improves crack resistance, and extends the service life of the material.

[0133] (6) Improved high performance with low addition amount of additives.

[0134] The recommended addition ratio is only 3% to 6% of the curing agent mass, which can significantly improve the curing efficiency and overall performance, greatly reduce material costs, and achieve more efficient performance optimization.

[0135] The above is a further detailed description of the present invention in conjunction with specific preferred embodiments, and the specific implementation of the present invention should not be considered to be limited to these descriptions. For those skilled in the art of the present invention, without departing from the concept of the present invention, several simple deductions or substitutions can be made, which should be considered to fall within the scope of protection of the present invention.

Claims

1. A geopolymer-based curing agent additive, characterized in that: The invention comprises raw material components composed in the following mass percentages: 40% to 50% of aromatic hydroxyl multi-base polymer, 10% to 15% of sodium persulfate, 15% to 20% of calcium oxide, 10% to 15% of magnesium oxide, and 10% to 15% of potassium sulfate.

2. The geopolymer-based curing agent according to claim 1, characterized in that: The aromatic hydroxyl multi-radical polymer has an aromatic ring as its core, and contains active groups in its molecular structure: carboxyl, alcoholic hydroxyl, phenolic hydroxyl, methoxy and carbonyl groups, wherein the active groups are composed according to the following mass percentages: phenolic hydroxyl 30% to 40%, carboxyl 20% to 30%, alcoholic hydroxyl 10% to 20%, methoxy 5% to 15%, and carbonyl 5% to 10%.

3. A geopolymer-based curing agent, characterized in that: The invention comprises raw material components composed in the following mass percentages: 45% to 55% of waste slag powder, 25% to 35% of Portland cement, 15% to 25% of an alkali activator, and 3% to 6% of the geopolymer-based curing agent additive as claimed in claim 1 or 2.

4. The geopolymer-based curing agent according to claim 3, characterized in that The alkali activator includes one or more of the following components: water glass, industrial waste alkali; When the alkaline activator includes multiple components, the mass percentage of each component in different cases is as follows: High-silicon system combination based on water glass: 50%~60% water glass, 20%~30% industrial waste alkali; An economical combination based on solid alkali: 40%~50% industrial waste alkali, 10%~20% water glass; Balanced combination: water glass 30%~40%, industrial waste alkali 20%~30%.

5. A method for applying a geopolymer-based curing agent additive, characterized in that: The following steps are involved: a1. The aromatic hydroxyl multi-radical polymer is used as the core component, and other inorganic components are added according to the designed proportions. The mass percentages of the added components are: aromatic hydroxyl multi-radical polymer 40%~50%, sodium persulfate 10%~15%, calcium oxide 15%~20%, magnesium oxide 10%~15%, and potassium sulfate 10%~15%; a2. Store the mixed additives in a sealed container for later use.

6. The method for applying the geopolymer-based curing agent according to claim 5, characterized in that: In step a1, the preparation process of the aromatic hydroxyl multi-radical polymer includes: a11. Raw material selection: The raw material components are composed of the following percentages by mass: 35-45% phenol, 25-30% p-carboxybenzoic acid, 10-15% methanol, and 5-10% benzaldehyde; a12 esterification reaction: Phenol and p-carboxybenzoic acid were mixed, followed by the addition of concentrated sulfuric acid as a catalyst, and the reaction was heated at 120 ° C for 2 hours to obtain a phenol ester intermediate; a13 etherification reaction: The generated phenol ester intermediate was mixed with methanol, aluminum chloride was added as a catalyst, and heated at 150 ° C for 4 hours to carry out etherification reaction to obtain a methoxy-containing intermediate; a14 oxidation reaction: benzaldehyde was added to the methoxy-containing intermediate, 6ml of 30% hydrogen peroxide was added for oxidation to generate a carbonyl group, the reaction temperature was controlled at 80 ° C, the reaction was allowed to proceed for 1 hour to obtain a carbonyl-containing intermediate; a15. Polymerization reaction: The obtained carbonyl-containing intermediate is diluted with dichloromethane solvent, aluminum chloride is added as a polymerization catalyst, and then heated to 180 ° C. The reaction is maintained for 12 hours to complete the polymerization reaction. After the reaction is completed, it is cooled to room temperature; finally, the polymer is washed to remove unreacted monomer and catalyst, and the solvent is removed by rotary evaporation or vacuum drying to obtain an aromatic hydroxyl multi-base polymer.

7. A method for applying a geopolymer-based curing agent, characterized in that: The following steps are involved: b1. Preparation and pretreatment of curing agent raw materials: The waste slag powder is sieved to ensure uniform particle distribution. The alkali activator is prepared by mixing one or more components of water glass, silicate, and industrial waste alkali. Standard specifications of Portland cement are selected; b2 improved additive preparation: according to claim 5, the application method of the geopolymer-based curing agent additive prepared additive; b3. Mixing process: Add 45%~55% by mass of waste slag powder, 25%~35% by mass of Portland cement, and 15%~25% by mass of alkali activator into a mixer and mix well. Then add 3%~6% by mass of additives and mix well.

8. The method for applying the geopolymer-based curing agent according to claim 7, characterized in that: In step b3, before adding the auxiliary agent in the curing process, the following operations are performed on the auxiliary agent: Use a mechanical stirrer to mix in two stages: low speed mixing in the first stage to achieve initial uniformity, and medium speed mixing in the second stage to achieve full dispersion.

9. The method for applying the geopolymer-based curing agent according to claim 8, characterized in that: In step b3, the two-stage mixing method of the auxiliary agent is divided into the following situations: Case 1: Direct transition method: Immediately after the low-speed mixing stage, the speed is gradually increased to the medium-speed stage; Case 2: If incompletely dispersed particles or uneven mixing occur during the mixing process, pause and perform scraping operations after the low-speed mixing stage, and then enter the medium-speed mixing stage; Case 3: If on-site conditions permit, temporarily mix all the components of the additive before use. The recommended order of addition is: first, fully stir the aromatic hydroxyl multi-polymer, calcium oxide, magnesium oxide, and potassium sulfate into a mixture at a low-speed mixing stage; second, add sodium persulfate alone to the mixture at a medium-speed mixing stage and fully stir.

10. The application method of the geopolymer-based curing agent according to claim 7, characterized in that: Step b3 includes the following two application methods: b31. The waste slag powder, Portland cement, alkali activator and the material to be solidified are uniformly mixed to obtain a mixed slurry, and the moisture content is controlled at 50~80% during the process; b32. Mix the waste slag powder, Portland cement and alkali activator evenly to prepare a geopolymer mixed slurry. The water-cement ratio can be controlled at 0.3~0.5 during the process.

11. The method for applying the geopolymer-based curing agent according to claim 7, characterized in that: Also includes the steps: b4. Mold forming: Select a mold, pour the mixed slurry into the mold, and vibrate the mold to remove bubbles in the slurry; b5. Project site pouring: pour the mixed slurry into the designated area of ​​the project site; b6. Curing: The slurry is left to solidify under natural conditions to obtain a solidified body, which is then covered or cured according to indoor and on-site conditions.