Gel dry water fire extinguishing agent with high stability and high water-retaining property and preparation method of gel dry water fire extinguishing agent

Abstract

The invention discloses a gel dry water fire extinguishing agent with high stability and high water-retaining property and a preparation method of the gel dry water fire extinguishing agent. The gel dry water fire extinguishing agent is of a composite structure formed by combining hydrophobic nano silicon dioxide and ferrocene to form an inert shell, combining an anion and nonionic compound solution and a liquid core gel system cross-linking solution to form a gel dry water liquid core, and wrapping the gel dry water liquid core by the inert shell. The preparation method comprises the following steps: S1, preparing an anionic and nonionic compound solution; s2, preparing a liquid core gel system cross-linking solution; s3, mixing and stirring the anionic and nonionic compound solution and the liquid core gel system cross-linking solution to obtain a gel dry water liquid core stock solution; and S4, hydrophobic nano silicon dioxide, ferrocene and the gel dry water liquid core stock solution are mixed and stirred at a high speed through a precise high-speed dispersion machine, tiny liquid drops of the gel dry water liquid core stock solution are evenly wrapped by the hydrophobic nano silicon dioxide and the ferrocene, and finally the gel dry water fire extinguishing agent is formed.

Description

Technical Field

[0001] The invention relates to the field of fire extinguishing agents, and in particular to a gel dry water fire extinguishing agent with high stability and high water retention and a preparation method thereof. Background Art

[0002] Fire has always been one of the major disasters that endangers human life and health, causes property losses and damages the ecological environment. According to the Montreal Protocol and its amendments, countries have gradually reduced and eventually banned the production and use of halon fire extinguishing agents. It is urgent to explore a high-efficiency, green and environmentally friendly fire extinguishing material as a substitute for halon fire extinguishing agents. Domestic and foreign scholars have conducted a lot of research on the improvement or innovation of the formula of clean fire extinguishing agents, but the research objects are limited to the improvement of water-based fire extinguishing agents such as fluorine-free foam fire extinguishing agents and fine water mist, as well as the research and development of gas fire extinguishing agents. Dry water materials are a new type of fire extinguishing material composed of a combination of solid and liquid phases and are used in the field of fire fighting. However, the existing dry water materials have always had the pain point of poor water retention and stability, and there is an urgent need to find a way to improve this pain point.

[0003] In order to improve the two major problems of poor water retention and poor stability of dry water materials, scholars have made various attempts from the aspects of preparation methods and additives, and have noticed the excellent performance of gel systems, and have begun to study the application of gel systems in dry water materials. Han et al. found that adding gel can not only significantly enhance the structural strength of dry water materials, but also improve the fire extinguishing performance through its characteristics. Chen et al. modified dry water materials with sodium alginate and studied the stability and fire extinguishing efficiency of modified dry water materials. Compared with ordinary dry water materials, the water loss rate of modified dry water composite materials is reduced, and its pressure resistance and stability are significantly improved. Among them, sodium alginate is a natural polysaccharide material, which is light yellow powder, odorless, non-toxic, has good stability in acid and alkali environments, excellent performance, and is an important raw material for improving the performance of dry water materials. Han et al. pointed out that the addition of gelling agent can delay the evaporation of water from dry water, but its moisturizing effect is still not ideal. Wang et al. found that the incorporation of SDBS enhanced the mixing and dispersion of the internal aqueous solution during stirring, resulting in the internal space of the particles being more effectively occupied by various additives, thereby increasing the packing density and making the mixing of the gelling agent and other components more uniform.

[0004] By searching relevant patents, it is found that some inventors have carried out research on the fire extinguishing performance and explosion suppression performance of dry water materials under different compounding schemes. For example, the Chinese patent with the authorization publication number CN117717747A proposes a green and environmentally friendly dry water fire extinguishing agent formula, and the dry water material formula has a strong fire extinguishing efficiency, but the water retention and stability performance have not been studied. Another example is the Chinese patent with the publication number CN118956344A, which proposes a dry water explosion suppression material formula for targeted suppression of hazardous chemical explosions, but its main purpose is to suppress the explosion hazard of different hazardous chemicals, and it has not made relevant measurements on water retention and stability. The Chinese patent with the publication number CN118421334A provides a method for preparing a high specific surface area gel dry water powder flame retardant, pointing out that the addition of TiO2 can enhance the mechanical strength and stability of the gel and promote the oxidative decomposition of smoke particles during combustion, but there is no data to confirm its excellent water retention performance. As a new type of fire extinguishing material, dry water material not only meets the requirements of fluidity and bulk density, but also its water retention and stability are crucial in fire extinguishing. If the water retention is low, it will largely lead to a slow cooling rate of dry water material during fire extinguishing, and the fire extinguishing efficiency will be greatly reduced; poor stability will lead to structural rupture during eruption, and the powder particles will not be able to reach the fire extinguishing area, which is not conducive to fire fighting.

[0005] Summarizing the above literature, it is found that the current dry water materials still have two major problems: poor water retention and poor stability. Previous studies have focused on the integration of gel systems into dry water materials, but there are few studies on improving the overall performance of dry water materials through the cross-linking of gelling systems and other additives. Based on this, the present invention designs and conducts gel dry water compounding experiments of cross-linking systems under different working conditions to study the influence of the cross-linking system on the stability and water retention of dry water materials, in order to obtain a gel dry water fire extinguishing agent with high stability and high water retention. Summary of the invention

[0006] The purpose of the present invention is to address the above-mentioned problems and to provide a high-stability and high-water-retention gel dry water fire extinguishing agent and a preparation method thereof, which can improve the ability of dry water materials to withstand external pressure, resist internal water loss, enhance water retention performance, and greatly improve fire extinguishing efficiency through the synergistic fire extinguishing effect of physical inhibition and chemical inhibition.

[0007] In order to achieve the above object, the technical solution of the present invention is: A high-stability and high-water-retention gel dry water fire extinguishing agent, wherein the gel dry water fire extinguishing agent is a composite structure formed by combining hydrophobic nano-silica and ferrocene to form an inert shell, combining an anionic and non-ionic composite solution with a liquid core gel system cross-linking solution to form a gel dry water liquid core, and the gel dry water liquid core is wrapped by the inert shell to form the composite structure.

[0008] Furthermore, the raw materials of the gel dry water fire extinguishing agent include hydrophobic nano-silica, ferrocene, anionic and nonionic compound solution, and liquid core gel system cross-linking solution; the mass parts of each raw material are: 8 parts of hydrophobic nano-silica, 2 parts of ferrocene, 50 parts of anionic and nonionic compound solution, and 50 parts of liquid core gel system cross-linking solution.

[0009] Furthermore, the particle size of the hydrophobic nano-silica is 15 to 40 nm, and the SiO2 content in the hydrophobic nano-silica is ≥ 99.8%.

[0010] Furthermore, the ferrocene is a light yellow powder and is insoluble in water, has a relative molecular mass of 186, and a content of ≥99%.

[0011] Furthermore, the anionic and nonionic composite solution is prepared by compounding anionic surfactant, nonionic surfactant and deionized water; in the anionic and nonionic composite solution, the mass fraction of anionic surfactant is 0.01 part, the mass fraction of nonionic surfactant is 0.01 part, and the rest is deionized water.

[0012] Furthermore, the anionic surfactant is a mixture of one or more of sodium dodecylbenzene sulfonate (SDBS), sodium dodecyl sulfate (SDS), and sodium polyoxyethylene fatty alcohol ether sulfate (AES), and the purity of sodium dodecylbenzene sulfonate (SDBS), sodium dodecyl sulfate (SDS), and sodium polyoxyethylene fatty alcohol ether sulfate (AES) is analytical grade.

[0013] Furthermore, the nonionic surfactant is alkyl polyglycoside (APG0810).

[0014] Furthermore, the liquid core gel system cross-linking solution is prepared by compounding sodium alginate, calcium salt, glucono-δ-lactone, and deionized water; in the liquid core gel system cross-linking solution, the mass fraction of sodium alginate is 1.5 parts, the mass fraction of calcium salt is 0.5 parts, the mass fraction of glucono-δ-lactone is 0.5 parts, and the rest is deionized water.

[0015] Furthermore, the sodium alginate is a natural polysaccharide material, which is in the form of light yellow powder, odorless, tasteless, non-toxic, and has good stability in both acidic and alkaline environments.

[0016] A method for preparing a gel dry water fire extinguishing agent with high stability and high water retention, comprising the following steps: S1. Pour anionic surfactant and nonionic surfactant into a beaker, add deionized water and stir to fully mix the anionic surfactant and nonionic surfactant in advance to obtain an anionic and nonionic composite solution; S2, preparing a liquid core gel system cross-linking solution; S3, adding the anionic and nonionic composite solution to the liquid core gel system cross-linking solution and stirring them fully to obtain the gel dry water liquid core stock solution; S4. Pour the hydrophobic nano-silica, ferrocene and gel dry water liquid core stock solution into a mixing barrel, and stir them at a high speed of 3000r / min at a temperature of 25°C for 5 minutes using a precision high-speed disperser. After high-speed stirring, the gel dry water liquid core stock solution is dispersed into tiny droplets and is evenly wrapped by the hydrophobic nano-silica and ferrocene, finally forming a gel dry water fire extinguishing agent.

[0017] Furthermore, the step S2 specifically includes the following steps: S21, heating a deionized water bath to 60° C., adding sodium alginate and calcium salt to the deionized water and stirring evenly to obtain a calcium salt suspension; S22, adding glucono-δ-lactone to the calcium salt suspension, stirring and dissolving to obtain a liquid core gel system cross-linking solution.

[0018] Furthermore, in step S21, after sodium alginate and calcium salt are added to deionized water, a high-speed dispersion machine is used to stir the mixture at a temperature of 25° C. and a speed of 3000 r / min for 20 minutes to obtain a calcium salt suspension.

[0019] Compared with the prior art, the present invention has the following advantages and positive effects: In the gel dry water fire extinguishing agent with high stability and high water retention prepared by the present invention, hydrophobic nano-silica and ferrocene form an inert shell. When ferrocene exists in a flame, it will decompose to produce iron atoms, and these iron atoms will further combine with oxygen, water, etc. to generate active intermediates such as FeO and Fe2O3. These active intermediates have the ability to combine with hydrogen, oxygen free radicals, etc. generated during the combustion process, thereby blocking the free radical chain, achieving the effect of inhibiting the continuous spread of flames and extinguishing fires; the anionic and non-ionic composite solution and the liquid core gel system cross-linking solution form a gel dry water liquid core with a three-dimensional grid structure, which can firmly lock water in the grid pores, enhance the overall stability of the material and further improve its water retention capacity; and the three-component components of ferrocene, the liquid core gel system cross-linking solution and water constitute a composite system of a fire extinguishing enhancer, forming a triple fire extinguishing enhancement of isolation and suffocation, heat absorption and cooling, and blocking chain reactions.

[0020] On the other hand, the present invention incorporates sodium alginate as a gel modifier into the cross-linking solution of the dry water material liquid core gel system. The alginic acid in the sodium alginate solution is very easy to react with divalent cations such as Ca 2+ , Pb 2+ 、Cd 2+The hydrogel is formed by cross-linking and forming a three-dimensional network structure. According to this characteristic, CaCO3 and glucono-δ-lactone are added to the sodium alginate solution. Glucono-δ-lactone will slowly release H during the hydrolysis process. + , reacts with CaCO3 to release Ca 2+ , forming a gel with alginate; due to H + The release is relatively slow, so there is enough time to prepare the cross-linked solution of the liquid core gel system into a "dry water" powder. The time for the cross-linked solution of the liquid core gel system to form a gel is controlled by the hydrolysis of glucono-δ-lactone. After the dry water powder is formed, the solution inside the powder is converted into a gel and the structure and morphology of the powder are kept unchanged, thereby improving the structural strength and water-locking performance of the finished product.

[0021] The gel dry water fire extinguishing agent of the present invention is non-toxic and harmless, has strong stable compressive resistance and high water retention performance; and its formula is simple, the preparation process is simple, and it has the characteristics of high stability and low water loss rate. It is suitable for the field of fire fighting and has great market promotion prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0023] Figure 1 It is a logic diagram of the preparation process of the present invention; Figure 2 This is a comparison chart of the stable compressive performance of the reference group 1-2 and Example 1 of the present invention; Figure 3 It is a comparison chart of the water retention performance at room temperature of the benchmark group 1-2 and Example 1 of the present invention. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work, any modifications, equivalent substitutions, improvements, etc., should be included in the protection scope of the present invention.

[0025] Example 1. This example discloses a gel dry water fire extinguishing agent with high stability and high water retention. The gel dry water fire extinguishing agent is a composite structure formed by a combination of hydrophobic nano-silica and ferrocene to form an inert shell, a combination of anionic and non-ionic composite solution and a liquid core gel system cross-linking solution to form a gel dry water liquid core, and the gel dry water liquid core is wrapped by the inert shell to form a composite structure.

[0026] The raw materials of the gel dry water fire extinguishing agent include hydrophobic nano-silica, ferrocene, anionic and nonionic compound solution, and liquid core gel system cross-linking solution; the mass parts of each raw material are respectively: 8 parts of hydrophobic nano-silica, 2 parts of ferrocene, 50 parts of anionic and nonionic compound solution, and 50 parts of liquid core gel system cross-linking solution.

[0027] The anionic and nonionic composite solution is prepared by mixing sodium dodecylbenzene sulfonate, alkyl polyglycoside and deionized water; in the anionic and nonionic composite solution, the mass fractions of sodium dodecylbenzene sulfonate and alkyl polyglycoside are respectively: 0.01 parts of sodium dodecylbenzene sulfonate, 0.01 parts of alkyl polyglycoside and 49.98 parts of deionized water; The liquid core gel system cross-linking solution is prepared by compounding sodium alginate, calcium carbonate, glucono-δ-lactone and deionized water; in the liquid core gel system cross-linking solution, the mass fractions of sodium alginate, calcium carbonate, glucono-δ-lactone and deionized water are respectively: 1.5 parts of sodium alginate, 0.5 parts of calcium carbonate, 0.5 parts of glucono-δ-lactone and 47.5 parts of deionized water.

[0028] At the same time, this embodiment also discloses a method for preparing the above-mentioned gel dry water fire extinguishing agent, such as Figure 1 As shown, the preparation method is as follows: The first step is to weigh 0.01 parts of sodium dodecylbenzene sulfonate and 0.01 parts of alkyl glycoside by mass using an electronic balance, add 49.98 parts of deionized water into a beaker, stir and dissolve with a glass rod to obtain an anionic and non-ionic composite solution; The second step is to heat deionized water to 60° C. in a water bath and take out 47.5 parts of it for standby use, weigh 1.5 parts of sodium alginate powder and 0.5 parts of calcium carbonate powder by mass using an electronic balance, pour them into a stirring barrel with the reserved 47.5 parts of deionized water, and stir them at a high speed of 3000 r / min at a temperature of 25° C. for 20 minutes using a precision high-speed disperser to obtain a calcium carbonate suspension for standby use; then weigh 0.5 parts of glucono-δ-lactone, add it to the calcium carbonate suspension, stir and dissolve it with a glass rod, and obtain a liquid core gel system cross-linking solution; The third step is to weigh 8 parts of hydrophobic nano-silica and 2 parts of ferrocene powder by mass using an electronic balance, add them into a beaker, and stir them evenly with a glass rod to obtain a hydrophobic nano-silica-ferrocene mixed powder; The fourth step is to add the anionic and non-ionic composite solution into the stirring barrel of the liquid core gel system cross-linking solution, and stir evenly with a glass rod to obtain the gel dry water liquid core stock solution; quickly add the hydrophobic nano-silica-ferrocene mixed powder into the stirring barrel, and use a precision high-speed disperser to stir at a temperature of 25°C and a speed of 3000r / min for 5 minutes, so that the hydrophobic nano-silica and ferrocene evenly wrap the stirred and dispersed gel dry water liquid core stock solution tiny droplets to obtain the gel dry water fire extinguishing agent.

[0029] Example 2. This example discloses a gel dry water fire extinguishing agent with high stability and high water retention. The gel dry water fire extinguishing agent is a composite structure formed by a combination of hydrophobic nano-silica and ferrocene to form an inert shell, a combination of anionic and non-ionic composite solution and a liquid core gel system cross-linking solution to form a gel dry water liquid core, and the gel dry water liquid core is wrapped by the inert shell to form a composite structure.

[0030] The raw materials of the gel dry water fire extinguishing agent include hydrophobic nano-silica, ferrocene, anionic and nonionic compound solution, and liquid core gel system cross-linking solution; the mass parts of each raw material are respectively: 8 parts of hydrophobic nano-silica, 2 parts of ferrocene, 50 parts of anionic and nonionic compound solution, and 50 parts of liquid core gel system cross-linking solution.

[0031] The anion and non-ion compound solution is prepared by compounding sodium dodecyl sulfate, alkyl polyglycoside, and deionized water; in the anion and non-ion compound solution, the mass fractions of sodium dodecyl sulfate and alkyl polyglycoside are respectively: 0.01 parts of sodium dodecyl sulfate, 0.01 parts of alkyl polyglycoside, and 49.98 parts of deionized water; The liquid core gel system cross-linking solution is prepared by compounding sodium alginate, calcium carbonate, glucono-δ-lactone and deionized water; in the liquid core gel system cross-linking solution, the mass fractions of sodium alginate, calcium carbonate, glucono-δ-lactone and deionized water are respectively: 1.5 parts of sodium alginate, 0.5 parts of calcium carbonate, 0.5 parts of glucono-δ-lactone and 47.5 parts of deionized water.

[0032] At the same time, this embodiment also discloses a method for preparing the above-mentioned gel dry water fire extinguishing agent, such as Figure 1 As shown, the preparation method is as follows: The first step is to weigh 0.01 parts of sodium dodecyl sulfate, 0.01 parts of alkyl glycoside and 49.98 parts of deionized water by weight into a beaker using an electronic balance, and stir and dissolve with a glass rod to obtain an anionic and nonionic composite solution; The second step is to heat deionized water to 60° C. in a water bath and take out 47.5 parts of it for standby use, weigh 1.5 parts of sodium alginate powder and 0.5 parts of calcium carbonate powder by mass using an electronic balance, pour them into a stirring barrel with the reserved 47.5 parts of deionized water, and stir them at a high speed of 3000 r / min at a temperature of 25° C. for 20 minutes using a precision high-speed disperser to obtain a calcium carbonate suspension for standby use; then weigh 0.5 parts of glucono-δ-lactone, add it to the calcium carbonate suspension, stir and dissolve it with a glass rod, and obtain a liquid core gel system cross-linking solution; The third step is to weigh 8 parts of hydrophobic nano-silica and 2 parts of ferrocene powder by mass using an electronic balance, add them into a beaker, and stir them evenly with a glass rod to obtain a hydrophobic nano-silica-ferrocene mixed powder; The fourth step is to add the anionic and non-ionic composite solution into the stirring barrel of the liquid core gel system cross-linking solution, and stir evenly with a glass rod to obtain the gel dry water liquid core stock solution; quickly add the hydrophobic nano-silica-ferrocene mixed powder into the stirring barrel, and use a precision high-speed disperser to stir at a temperature of 25°C and a speed of 3000r / min for 5 minutes, so that the hydrophobic nano-silica and ferrocene evenly wrap the stirred and dispersed gel dry water liquid core stock solution tiny droplets to obtain the gel dry water fire extinguishing agent.

[0033] Example 3. This example discloses a gel dry water fire extinguishing agent with high stability and high water retention. The gel dry water fire extinguishing agent is a composite structure formed by a combination of hydrophobic nano-silica and ferrocene to form an inert shell, a combination of anionic and non-ionic composite solution and a liquid core gel system cross-linking solution to form a gel dry water liquid core, and the gel dry water liquid core is wrapped by the inert shell to form a composite structure.

[0034] The raw materials of the gel dry water fire extinguishing agent include hydrophobic nano-silica, ferrocene, anionic and nonionic compound solution, and liquid core gel system cross-linking solution; the mass parts of each raw material are respectively: 8 parts of hydrophobic nano-silica, 2 parts of ferrocene, 50 parts of anionic and nonionic compound solution, and 50 parts of liquid core gel system cross-linking solution.

[0035] The anionic and nonionic composite solution is prepared by compounding sodium fatty alcohol polyoxyethylene ether sulfate, alkyl glycoside, and deionized water; in the anionic and nonionic composite solution, the mass fractions of sodium fatty alcohol polyoxyethylene ether sulfate and alkyl glycoside are respectively: 0.01 parts of sodium fatty alcohol polyoxyethylene ether sulfate, 0.01 parts of alkyl glycoside, and 49.98 parts of deionized water; The liquid core gel system cross-linking solution is prepared by compounding sodium alginate, calcium carbonate, glucono-δ-lactone and deionized water; in the liquid core gel system cross-linking solution, the mass fractions of sodium alginate, calcium carbonate, glucono-δ-lactone and deionized water are respectively: 1.5 parts of sodium alginate, 0.5 parts of calcium carbonate, 0.5 parts of glucono-δ-lactone and 47.5 parts of deionized water.

[0036] At the same time, this embodiment also discloses a method for preparing the above-mentioned gel dry water fire extinguishing agent, such as Figure 1 As shown, the preparation method is as follows: The first step is to weigh 0.01 parts of sodium fatty alcohol polyoxyethylene ether sulfate, 0.01 parts of alkyl glycoside and 49.98 parts of deionized water by weight into a beaker using an electronic balance, and stir and dissolve with a glass rod to obtain an anionic and non-ionic composite solution; The second step is to heat deionized water to 60° C. in a water bath and take out 47.5 parts of it for standby use, weigh 1.5 parts of sodium alginate powder and 0.5 parts of calcium carbonate powder by mass using an electronic balance, pour them into a stirring barrel with the reserved 47.5 parts of deionized water, and stir them at a high speed of 3000 r / min at a temperature of 25° C. for 20 minutes using a precision high-speed disperser to obtain a calcium carbonate suspension for standby use; then weigh 0.5 parts of glucono-δ-lactone, add it to the calcium carbonate suspension, stir and dissolve it with a glass rod, and obtain a liquid core gel system cross-linking solution; The third step is to weigh 8 parts of hydrophobic nano-silica and 2 parts of ferrocene powder by mass using an electronic balance, add them into a beaker, and stir them evenly with a glass rod to obtain a hydrophobic nano-silica-ferrocene mixed powder; The fourth step is to add the anionic and non-ionic composite solution into the stirring barrel of the liquid core gel system cross-linking solution, and stir evenly with a glass rod to obtain the gel dry water liquid core stock solution; quickly add the hydrophobic nano-silica-ferrocene mixed powder into the stirring barrel, and use a precision high-speed disperser to stir at a temperature of 25°C and a speed of 3000r / min for 5 minutes, so that the hydrophobic nano-silica and ferrocene evenly wrap the stirred and dispersed gel dry water liquid core stock solution tiny droplets to obtain the gel dry water fire extinguishing agent.

[0037] The present invention focuses on constructing a gel dry water fire extinguishing agent with high stability and high water retention. Through the unique core-shell system, liquid core system and fire extinguishing enhancer composite system design, the long-term stability and high-efficiency fire extinguishing performance of the fire extinguishing agent in complex environments are achieved; the compounding scheme in the present invention adopts a fluorine-free formula, selects hydrocarbon surfactants, hydrophobic nano-silica, flame retardants, gelling agents, gel inducers and fire extinguishing enhancers as raw materials for compounding dry water materials, and practices the concept of green and low-carbon development.

[0038] During the preparation, the present invention firstly performs dry mixing of ferrocene and hydrophobic nano-silica, which enables the hydrophobic nano-silica particles to be fully adhered to the ferrocene particles (the nano-particles are only 1% of the cement particles), so that the ferrocene has the hydrophobicity of the hydrophobic nano-silica and is not easily wetted by the liquid core to become a ferrocene suspension; and because the hydrophobic nano-silica has a small particle size, the electronic structure on its surface is disturbed and the internal crystal structure undergoes a great change, the number of atoms around the surface is continuously increased, resulting in an increase in the specific surface area of ​​the nano-material; because there are no adjacent particles around the nano-silica particles, the surface particles have higher energy, resulting in a larger surface energy and poorer stability, and are easy to combine with other atoms in the outside world, thereby increasing their stability; when the nano-silica particles are first mixed with the ferrocene, they will be adsorbed on the surface as much as possible, thereby hydrophobic modification of the ferrocene is performed, which is conducive to the uniform dispersion of the ferrocene on the surface of the dry water particles, and improves the improvement effect on the performance of the dry water material.

[0039] The present invention utilizes the cross-linking property of sodium alginate itself, and controls the cross-linking reaction speed through GDL (glucono-δ-lactone). At the same time, the dispersibility of the gel dry water liquid core stock solution can be controlled through the synergistic effect of the calcium salt solution and the anionic-nonionic surfactant, thereby controlling the particle size of the prepared dry water particles, and realizing further optimization and improvement of the cross-linking system; and, the present invention effectively realizes the optimization and improvement of the compressive strength, water retention and fire extinguishing performance of the dry water material through the coordination of the inert hydrophobic shell system formed by ferrocene-hydrophobic nano-silica and the calcium alginate cross-linking solution system, and further improves the use effect of the gel dry water fire extinguishing agent.

[0040] Below, benchmark group 1 and benchmark group 2 are prepared to conduct performance comparison tests with the gel dry water fire extinguishing agent prepared by the present invention to verify the performance superiority of the gel dry water fire extinguishing agent in the present invention.

[0041] Benchmark Group 1: Pure Water The preparation method of dry water is as follows: The first step is to use an electronic balance to weigh 10 parts of hydrophobic nano-silicon dioxide and 100 parts of deionized water into a mixing bucket; In the second step, a precision high-speed disperser is used to stir at a temperature of 25°C and a speed of 5000r / min for 4 minutes, so that the hydrophobic nano-silica uniformly wraps the stirred and dispersed deionized water droplets to obtain pure dry water.

[0042] Baseline Group 2: The preparation method of gel-dried water is as follows: In the first step, 98.5 parts of deionized water are poured into a beaker, heated in a water bath to 60° C., 1.5 parts of sodium alginate are weighed by weight and stirred with a glass rod to dissolve to prepare a sodium alginate solution; The second step is to use an electronic balance to weigh 10 parts of hydrophobic nano-silicon dioxide by mass, and add them into the stirring barrel after the sodium alginate solution is cooled to room temperature; The third step is to use a precision high-speed disperser to stir at a temperature of 25°C and a speed of 3000r / min for 5 minutes, so that the hydrophobic nano-silica uniformly wraps the stirred and dispersed tiny droplets of sodium alginate solution to obtain gel dry water.

[0043] The pure water dry water, gel dry water prepared in reference groups 1 to 2 and the ferrocene-based gel dry water samples prepared in Examples 1 to 3 were tested for fluidity, stability and water retention.

[0044] After testing, under an external pressure of 500g, the pure water dry water particles were almost completely broken, the gel dry water particles were slightly broken, and the ferrocene-based gel dry water materials prepared in Examples 1 to 3 had almost no broken particles. Figure 2 As shown; After testing, after standing for 5 minutes at room temperature, the water content of the pure water dry water particles almost completely disappeared, the gel dry water particles shrank slightly, and the ferrocene-based gel dry water material prepared by the present invention did not change at all. Figure 3 As shown; pass Figure 2 , Figure 3 It can be seen that the novel ferrocene-based gel dry water material prepared in the embodiment of the present invention has significantly improved stable compressive resistance and water retention performance.

[0045] In addition, this experiment used a constant temperature drying oven to test the water retention performance of the pure water dry water, gel dry water prepared in reference groups 1 to 2 and the ferrocene-based gel dry water samples prepared in Examples 1 to 3. 20 parts of each sample were weighed and placed in a crucible. After the constant temperature drying oven was heated to 60°C, the crucible was placed in the drying oven and taken out after one hour. The samples were weighed with an electronic balance and the water retention performance of the samples was characterized by mass loss. The test results are shown in Table 1.

[0046] Table 1 Performance test results of the benchmark group and example samples Example Outflow rate (ml / s) Angle of repose / ° Water loss rate g / h Benchmark Group 1 1.94 34 10.28 Benchmark Group 2 4.72 29 6.56 Example 1 6.54 26 5.92 Example 2 6.28 25 6.08 Example 3 6.16 27 6.14 It can be clearly seen from the test data in Table 1 that the ferrocene-based gel dry water extinguishing agent prepared in Example 1 has the fastest outflow rate of 6.54 ml / s and the lowest water loss rate of 5.92 g / h; the angle of repose of Example 2 is the smallest, which is 25°; this effectively proves that the ferrocene-based gel dry water fire extinguishing agent in the present invention has excellent stability and water retention capacity, and has a breakthrough application value in the field of fire protection.

[0047] In the gel dry water fire extinguishing agent with high stability and high water retention prepared by the present invention, hydrophobic nano-silica and ferrocene form an inert shell. When ferrocene exists in a flame, it will decompose to produce iron atoms, and these iron atoms will further combine with oxygen, water, etc. to generate active intermediates such as FeO and Fe2O3. These active intermediates have the ability to combine with hydrogen, oxygen free radicals, etc. generated during the combustion process, thereby blocking the free radical chain, achieving the effect of inhibiting the continuous spread of flames and extinguishing fires; the anionic and non-ionic composite solution and the liquid core gel system cross-linking solution form a gel dry water liquid core with a three-dimensional grid structure, which can firmly lock water in the grid pores, enhance the overall stability of the material and further improve its water retention capacity; and the three-component components of ferrocene, the liquid core gel system cross-linking solution and water constitute a composite system of a fire extinguishing enhancer, forming a triple fire extinguishing enhancement of isolation and suffocation, heat absorption and cooling, and blocking chain reactions.

[0048] On the other hand, the present invention incorporates sodium alginate as a gel modifier into the cross-linking solution of the dry water material liquid core gel system. The alginic acid in the sodium alginate solution is very easy to react with divalent cations such as Ca 2+ , Pb 2+ 、Cd 2+ The hydrogel is formed by cross-linking and forming a three-dimensional network structure. According to this characteristic, CaCO3 and glucono-δ-lactone are added to the sodium alginate solution. Glucono-δ-lactone will slowly release H during the hydrolysis process. + , reacts with CaCO3 to release Ca 2+ , forming a gel with alginate; due to H + The release is relatively slow, so there is enough time to prepare the cross-linked solution of the liquid core gel system into a "dry water" powder. The time for the cross-linked solution of the liquid core gel system to form a gel is controlled by the hydrolysis of glucono-δ-lactone. After the dry water powder is formed, the solution inside the powder is converted into a gel and the structure and morphology of the powder are kept unchanged, thereby improving the structural strength and water-locking performance of the finished product.

[0049] The gel dry water fire extinguishing agent of the present invention is non-toxic and harmless, has strong stable compressive resistance and high water retention performance; and its formula is simple, the preparation process is simple, and it has the characteristics of high stability and low water loss rate. It is suitable for the field of fire fighting and has great market promotion prospects.

Claims

1. A gel dry water fire extinguishing agent with high stability and high water retention, characterized in that: The gel dry water fire extinguishing agent is a composite structure formed by combining hydrophobic nano-silicon dioxide and ferrocene to form an inert shell, combining anionic and non-ionic composite solution with a liquid core gel system cross-linking solution to form a gel dry water liquid core, and the gel dry water liquid core is wrapped by the inert shell to form a composite structure.

2. The gel dry water fire extinguishing agent with high stability and high water retention as claimed in claim 1, characterized in that: The raw materials of the gel dry water fire extinguishing agent include hydrophobic nano-silica, ferrocene, anionic and nonionic compound solution, and liquid core gel system cross-linking solution; the mass parts of each raw material are respectively: 8 parts of hydrophobic nano-silica, 2 parts of ferrocene, 50 parts of anionic and nonionic compound solution, and 50 parts of liquid core gel system cross-linking solution.

3. The gel dry water fire extinguishing agent with high stability and high water retention as claimed in claim 1, characterized in that: The particle size of the hydrophobic nano-silicon dioxide is 15-40 nm, and the SiO2 content in the hydrophobic nano-silicon dioxide is ≥99.8%.

4. The gel dry water fire extinguishing agent with high stability and high water retention as claimed in claim 1, characterized in that: The anionic and nonionic composite solution is prepared by compounding anionic surfactant, nonionic surfactant and deionized water; in the anionic and nonionic composite solution, the mass fraction of anionic surfactant is 0.01 part, the mass fraction of nonionic surfactant is 0.01 part, and the rest is deionized water.

5. The gel dry water fire extinguishing agent with high stability and high water retention as claimed in claim 4, characterized in that: The anionic surfactant is a mixture of one or more of sodium dodecylbenzene sulfonate, sodium dodecyl sulfate, and sodium polyoxyethylene fatty alcohol ether sulfate.

6. The gel dry water fire extinguishing agent with high stability and high water retention as claimed in claim 4, characterized in that: The nonionic surfactant is an alkyl polyglycoside.

7. The gel dry water fire extinguishing agent with high stability and high water retention as claimed in claim 4, characterized in that: The cross-linking solution of the liquid core gel system is prepared by compounding sodium alginate, calcium salt, glucono-δ-lactone and deionized water; in the cross-linking solution of the liquid core gel system, the mass fraction of sodium alginate is 1.5 parts, the mass fraction of calcium salt is 0.5 parts, the mass fraction of glucono-δ-lactone is 0.5 parts, and the rest is deionized water.

8. A method for preparing the gel dry water fire extinguishing agent with high stability and high water retention as claimed in claim 7, characterized in that: The following steps are involved: S1. Pour anionic surfactant and nonionic surfactant into a beaker, add deionized water and stir to fully mix the anionic surfactant and nonionic surfactant in advance to obtain an anionic and nonionic composite solution; S2, preparing a liquid core gel system cross-linking solution; S3, adding the anionic and nonionic composite solution to the liquid core gel system cross-linking solution and stirring them fully to obtain the gel dry water liquid core stock solution; S4. Pour the hydrophobic nano-silica, ferrocene and gel dry water liquid core stock solution into a mixing barrel, and stir them at a high speed of 3000r / min at a temperature of 25°C for 5 minutes using a precision high-speed disperser. After high-speed stirring, the gel dry water liquid core stock solution is dispersed into tiny droplets and is evenly wrapped by the hydrophobic nano-silica and ferrocene, finally forming a gel dry water fire extinguishing agent.

9. The method for preparing the gel dry water fire extinguishing agent with high stability and high water retention as claimed in claim 8, characterized in that: The step S2 specifically includes the following steps: S21, heating a deionized water bath to 60° C., adding sodium alginate and calcium salt to the deionized water and stirring evenly to obtain a calcium salt suspension; S22, adding glucono-δ-lactone to the calcium salt suspension, stirring and dissolving to obtain a liquid core gel system cross-linking solution.

10. The method for preparing the gel dry water fire extinguishing agent with high stability and high water retention as claimed in claim 9, characterized in that: In the step S21, after sodium alginate and calcium salt are added to deionized water, a calcium salt suspension is obtained by high-speed stirring at a temperature of 25° C. and a rotation speed of 3000 r / min for 20 minutes using a precision high-speed disperser.

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