Fluorine-free foam extinguishing agent and preparation method thereof

Abstract

The invention relates to the technical field of fire safety, and discloses a fluoride-free foam extinguishing agent and a preparation method thereof.The fluoride-free foam extinguishing agent comprises a hydrocarbon surfactant, a carboxyl modified organosilicon surfactant, an organic solvent, water and an optional pH regulator; the carboxyl modified organic silicon surfactant is obtained by modifying an organic silicon surfactant by using maleic anhydride; the hydrocarbon surface active agent is selected from at least two of an anionic hydrocarbon surface active agent, a cationic hydrocarbon surface active agent, an amphoteric hydrocarbon surface active agent and a nonionic hydrocarbon surface active agent. Under the interaction of the components, the fluoride-free foam extinguishing agent disclosed by the invention has excellent fire extinguishing performance and burning resistance. In addition, the raw materials of the fluoride-free foam extinguishing agent are easy to obtain and low in cost, the biodegradability of all the raw material components is small, and the fluoride-free foam extinguishing agent does not contain a fluorocarbon surfactant thoroughly, is small in environmental pollution and does not have toxic or side effects.

Description

Technical Field

[0001] The invention relates to the technical field of fire safety, and in particular to a fluorine-free foam fire extinguishing agent and a preparation method thereof. Background Art

[0002] Protecting society from the threat of fire is the top priority of firefighting work, and foam fire extinguishing agents are important materials for firefighting. Common foam fire extinguishing agents are divided into protein-type foam fire extinguishing agents and synthetic foam fire extinguishing agents. Among them, although protein-type foam fire extinguishing agents do not contain fluorocarbon surfactants, their main component is hydrolyzed protein, which contains a high content of organic matter, which will cause a higher organic load on the ecological environment. In addition, protein-type foam fire extinguishing agents are difficult to extinguish flammable liquid fires, have low fire extinguishing efficiency, and have poor anti-burning performance. Therefore, synthetic foam fire extinguishing agents are currently more widely used.

[0003] Synthetic foam fire extinguishing agents are divided into synthetic foam fire extinguishing agents, aqueous film-forming foam fire extinguishing agents (AFFF), Class A foam fire extinguishing agents, etc. Aqueous film-forming foam fire extinguishing agents, because they can spread quickly on the burning oil surface, inhibit the volatilization of flammable liquids, and thus achieve the effect of rapid fire extinguishing, have been proven to be the most commonly used and most effective method to extinguish flammable liquid fires, and are now widely used in the petroleum and petrochemical industries. The excellent performance of aqueous film-forming foam fire extinguishing agents is mainly due to the fact that they contain high-performance long-chain fluorocarbon surfactants. Long-chain fluorocarbon surfactants refer to surfactants when all or part of the hydrogen atoms in hydrocarbon surfactants are replaced by fluorine atoms. This type of surfactant has high surface activity, high chemical stability, high thermal stability, and hydrophobicity and oleophobicity, and is the most active surfactant to date. However, in recent years, studies have found that long-chain fluorocarbon surfactants represented by perfluorooctane sulfonic acid (PFOS) and related salts are difficult to degrade, and there are serious ecological destructiveness and environmental pollution problems. Due to its strong harm to the environment, countries around the world have formulated increasingly stringent environmental regulations to restrict the use of PFOS. Therefore, it is of great research significance to strengthen the control of PFOS and develop efficient and environmentally friendly PFOS-free foam fire extinguishing agents.

[0004] At present, there are two main directions for exploring alternatives to PFOS fluorocarbon surfactants: one is to synthesize short-chain fluorinated surfactants (C4~C6) to replace PFOS; however, studies have found that as the length of the fluorocarbon chain shortens, its bioaccumulation and environmental harm decrease, while its surface activity, fire extinguishing ability and other properties are also affected, making it difficult to take into account both environmental protection and practical performance; and, my country does not have the technology for stable and efficient production of C4~C6 short fluorocarbon chain fluorocarbon surfactants, and its source mainly relies on imported products (such as products produced by DuPont, 3M and Dow Corning), which are costly. In addition, the use cycle of short-chain fluorocarbon surfactants is short, and there is not enough data to support whether they are truly environmentally friendly; the other is to synthesize new environmentally friendly fluorine-free surfactants or to compound multiple surfactants to replace PFOS. However, although this fluorine-free environmentally friendly foam fire extinguishing agent is environmentally friendly, its fire extinguishing performance is poor. Summary of the invention

[0005] The purpose of the present invention is to overcome the problems of the prior art that the environmental protection and practicality of PFOS-free aqueous film-forming foam fire extinguishing agents are difficult to balance, the environmental protection needs to be verified, the fire extinguishing performance is poor, and the cost is high, and to provide a fluorine-free foam fire extinguishing agent and a preparation method thereof. The fluorine-free foam fire extinguishing agent is not only environmentally friendly, but also has excellent fire extinguishing performance.

[0006] In order to achieve the above object, the present invention provides a fluorine-free foam fire extinguishing agent on one hand, wherein the fluorine-free foam fire extinguishing agent contains a hydrocarbon surfactant, a carboxyl-modified silicone surfactant, an organic solvent, water and an optional pH regulator;

[0007] Wherein, the carboxyl-modified organosilicon surfactant is obtained by modifying the organosilicon surfactant with maleic anhydride;

[0008] The hydrocarbon surfactant is selected from at least two of anionic hydrocarbon surfactants, cationic hydrocarbon surfactants, amphoteric hydrocarbon surfactants and nonionic hydrocarbon surfactants.

[0009] Preferably, the carboxyl-modified silicone surfactant is prepared according to the following process:

[0010] The organic silicon surfactant, maleic anhydride and isopropanol are mixed and stirred, reacted at 60-90° C. for 2-8 hours, and then cooled and purified.

[0011] Preferably, the organosilicon surfactant is selected from one or more of hydroxy polyether modified organosiloxane, terminal hydroxyl organosilicon block polyether, hydroxy acrylic organosilicon and hydroxy polyester organosilicon.

[0012] Preferably, the weight ratio of the organic silicon surfactant to maleic anhydride is 1:0.5-3.

[0013] Preferably, the weight ratio of the isopropanol to the total weight of the silicone surfactant and maleic anhydride is 10-40:100.

[0014] Preferably, based on the total weight of the fluorine-free foam fire extinguishing agent, the content of the hydrocarbon surfactant is 5-35wt%, the content of the carboxyl-modified silicone surfactant is 0.5-5wt%, the content of the organic solvent is 1-8wt%, and the content of the pH regulator is 0.1-10wt%.

[0015] Preferably, the anionic hydrocarbon surfactant is selected from one or more of sodium dodecyl sulfate, sodium dodecylbenzene sulfonate, sodium fatty alcohol polyoxyethylene ether sulfate and sodium α-olefin sulfonate.

[0016] Preferably, the cationic hydrocarbon surfactant is selected from one or more of dodecyl dimethyl benzyl ammonium chloride and polyoxyethylene alkyl amide.

[0017] Preferably, the amphoteric hydrocarbon surfactant is selected from one or more of cocamidopropyl betaine, dodecyl dimethyl betaine, 3-sulfopropyl dodecyl dimethyl betaine and 2-undecyl-N-acetoxy-N(2-hydroxyethyl)imidazoline.

[0018] Preferably, the nonionic hydrocarbon surfactant is selected from one or more of alkyl glycosides, fatty alcohol polyoxyethylene ethers and alkylphenol polyoxyethylene ethers.

[0019] Preferably, the organic solvent is selected from one or more of ethylene glycol, diethylene glycol butyl ether and isobutyl alcohol.

[0020] Preferably, the pH adjuster is selected from one or more of citric acid, lactic acid, tartaric acid, malic acid, phosphoric acid and acetic acid.

[0021] Preferably, the fluorine-free foam fire extinguishing agent further contains one or more of a corrosion inhibitor, a chelating agent and a preservative.

[0022] Preferably, the corrosion inhibitor is selected from one or more of benzotriazole, sodium tripolyphosphate and sodium hexametaphosphate.

[0023] Preferably, the chelating agent is disodium ethylenediaminetetraacetate.

[0024] Preferably, the preservative is selected from one or more of sodium benzoate, potassium sorbate and methyl paraben.

[0025] Preferably, the fluorine-free foam fire extinguishing agent contains, by weight percentage: 5-35wt% hydrocarbon surfactant, 0.5-5wt% carboxyl-modified silicone surfactant, 1-8wt% organic solvent, 0.1-1wt% corrosion inhibitor, 0.5-3wt% chelating agent, 0.1-1wt% preservative, and 0.1-10wt% pH adjuster.

[0026] The second aspect of the present invention provides a method for preparing the fluorine-free foam fire extinguishing agent as described above, the method comprising: mixing a hydrocarbon surfactant, a carboxyl-modified organic silicon surfactant, an organic solvent and water.

[0027] Preferably, the method comprises the following steps:

[0028] (1) mixing a hydrocarbon surfactant with a portion of water, and then adding a carboxyl-modified silicone surfactant to obtain a mixed solution A;

[0029] (2) mixing the organic solvent and the remaining water to obtain a mixed solution B;

[0030] (3) Mix the mixed solution B, the mixed solution A and the pH adjuster.

[0031] Preferably, step (2) comprises: mixing a corrosion inhibitor, a chelating agent, an organic solvent, a preservative and remaining water.

[0032] The fluorine-free foam fire extinguishing agent provided by the present invention contains a hydrocarbon surfactant, a carboxyl-modified silicone surfactant, an organic solvent, water and an optional pH adjusting agent. The silicone surfactant is modified by using maleic anhydride to improve the water solubility of the silicone surfactant and at the same time improve its surface activity. The foaming performance is improved by compounding the hydrocarbon surfactant. Through the joint action of the above components, the fluorine-free foam fire extinguishing agent provided by the present invention has high surface activity, high foam stability, good foaming ability and anti-burning ability, so that it has excellent fire extinguishing performance. In addition, the raw materials of the fluorine-free foam fire extinguishing agent provided by the present invention are easy to obtain, low in cost, the biodegradability of each raw material component is low, and it is completely free of fluorocarbon surfactants, has little pollution to the environment, and has no toxic side effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 1 is a hydrogen nuclear magnetic resonance spectrum of the organosilicon surfactant and the carboxyl-modified organosilicon surfactant in Example 1 of the present invention. DETAILED DESCRIPTION

[0034] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0035] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0036] The invention provides a fluorine-free foam fire extinguishing agent, which contains a hydrocarbon surfactant, a carboxyl-modified organic silicon surfactant, an organic solvent, water and an optional pH regulator.

[0037] The silane group and siloxane group with strong hydrophobic effect make the organosilicon surfactant have high surface activity, thereby being able to greatly reduce the surface tension of water. In addition, the organosilicon surfactant also has obvious advantages in stability, wettability, spreadability, etc., but its water solubility is poor, which limits its application. In the present invention, the carboxyl-modified organosilicon surfactant is obtained by modifying the organosilicon surfactant with maleic anhydride (i.e., maleic anhydride), so that not only the water solubility of the organosilicon surfactant is improved, but also its surface activity is not affected.

[0038] In a specific embodiment, the carboxyl-modified organosilicon surfactant is prepared according to the following process: the organosilicon surfactant, maleic anhydride and isopropanol are mixed, stirred and reacted, and then cooled and purified. Preferably, the reaction temperature is 60 to 90°C, and specifically, for example, it can be 60°C, 65°C, 70°C, 75°C, 80°C, 85°C or 90°C; the reaction time is 2 to 8h, and specifically, for example, it can be 2h, 2.5h, 3h, 4h, 5h, 6h, 7h or 8h. In the present invention, the purification is carried out by vacuum distillation.

[0039] In a preferred embodiment, the weight ratio of the organic silicon surfactant to maleic anhydride is 1:0.5-3.

[0040] In a preferred embodiment, the ratio of the weight of the isopropanol to the total weight of the silicone surfactant and maleic anhydride is 10-40:100.

[0041] The present invention does not limit the specific selection of the organosilicon surfactant, as long as it contains hydroxyl groups. In a preferred embodiment, the organosilicon surfactant is selected from one or more of hydroxy polyether modified organosilicon oxane, terminal hydroxyl organosilicon block polyether, hydroxy acrylic organosilicon and hydroxy polyester organosilicon, more preferably hydroxy polyether modified organosilicon oxane.

[0042] Taking the organosilicon surfactant as hydroxy polyether modified organosiloxane as an example, the following is the synthesis route of carboxyl modified organosilicon surfactant:

[0043]

[0044] Hydrocarbon surfactants are environmentally friendly and have good foaming properties. In the present invention, the hydrocarbon surfactant is selected from at least two of anionic hydrocarbon surfactants, cationic hydrocarbon surfactants, amphoteric hydrocarbon surfactants and nonionic hydrocarbon surfactants. By compounding the hydrocarbon surfactants, the foaming properties are further improved. For example, the compounding of hydrocarbon surfactants can be: compounding of anionic hydrocarbon surfactants and amphoteric hydrocarbon surfactants, compounding of anionic hydrocarbon surfactants, amphoteric hydrocarbon surfactants and nonionic hydrocarbon surfactants, and compounding of anionic surfactants and nonionic hydrocarbon surfactants.

[0045] In the present invention, the pH regulator is used to adjust the pH value of the fluorine-free foam fire extinguishing agent to a suitable range (7.0-9.5). It is understood that if the pH value of the prepared fluorine-free foam fire extinguishing agent is already 7.0-9.5, it is not necessary to add the pH regulator.

[0046] In a preferred embodiment, based on the total weight of the fluorine-free foam fire extinguishing agent, the content of the hydrocarbon surfactant is 5-35wt%, the content of the carboxyl-modified silicone surfactant is 0.5-5wt%, the content of the organic solvent is 1-8wt%, and the content of the pH regulator is 0.1-10wt%.

[0047] More preferably, based on the total weight of the fluorine-free foam fire extinguishing agent, the content of the hydrocarbon surfactant is 10-30wt%, the content of the carboxyl-modified silicone surfactant is 1-5wt%, the content of the organic solvent is 3-7wt%, and the content of the pH adjuster is 1-8wt%. Under the above ratio, the obtained fluorine-free foam fire extinguishing agent has better fire extinguishing performance.

[0048] In a preferred embodiment, the anionic hydrocarbon surfactant is selected from one or more of sodium dodecyl sulfate, sodium dodecylbenzene sulfonate, sodium fatty alcohol polyoxyethylene ether sulfate and sodium α-olefin sulfonate.

[0049] In a preferred embodiment, the cationic hydrocarbon surfactant is selected from one or more of dodecyl dimethyl benzyl ammonium chloride and polyoxyethylene alkyl amide.

[0050] In a preferred embodiment, the amphoteric hydrocarbon surfactant is selected from one or more of cocamidopropyl betaine, dodecyl dimethyl betaine, 3-sulfopropyl dodecyl dimethyl betaine and 2-undecyl-N-acetoxy-N(2-hydroxyethyl)imidazoline.

[0051] In a preferred embodiment, the nonionic hydrocarbon surfactant is selected from one or more of alkyl glycosides, fatty alcohol polyoxyethylene ethers and alkylphenol polyoxyethylene ethers.

[0052] By adding an organic solvent, it can not only play a solubilizing role, but also reduce the freezing point of the fluorine-free foam fire extinguishing agent. In the present invention, the organic solvent is selected from one or more of ethylene glycol, diethylene glycol butyl ether and isobutyl alcohol.

[0053] In the present invention, the pH adjuster is selected from one or more of citric acid, lactic acid, tartaric acid, malic acid, phosphoric acid and acetic acid, preferably citric acid, more preferably a citric acid aqueous solution with a mass concentration of 40%.

[0054] In order to further improve the comprehensive performance of the fluorine-free foam fire extinguishing agent, in a preferred embodiment, the fluorine-free foam fire extinguishing agent further contains one or more of a corrosion inhibitor, a chelating agent and a preservative. Most preferably, the fluorine-free foam fire extinguishing agent further contains a corrosion inhibitor, a chelating agent and a preservative.

[0055] In the present invention, the corrosion inhibitor is selected from one or more of benzotriazole, sodium tripolyphosphate and sodium hexametaphosphate.

[0056] By adding a preservative, the storage time of the fluorine-free foam fire extinguishing agent can be increased. In a preferred embodiment, the preservative is selected from one or more of sodium benzoate, potassium sorbate and methyl parahydroxybenzoate.

[0057] In a preferred embodiment, the fluorine-free foam fire extinguishing agent contains, by weight percentage: 5-35wt% hydrocarbon surfactant, 0.5-5wt% carboxyl modified silicone surfactant, 1-8wt% organic solvent, 0.1-1wt% corrosion inhibitor, 0.5-3wt% chelating agent, 0.1-1wt% preservative, 0.1-1wt% pH adjuster, and the balance is water.

[0058] More preferably, the fluorine-free foam fire extinguishing agent contains, by weight percentage: 10-30wt% hydrocarbon surfactant, 1-5wt% carboxyl-modified silicone surfactant, 3-7wt% organic solvent, 0.4-0.8wt% corrosion inhibitor, 1-3wt% chelating agent, 0.5-0.8wt% preservative, 1-8wt% pH adjuster, and the balance is water.

[0059] In the present invention, the water in the fluorine-free foam fire extinguishing agent is preferably deionized water, and more preferably, based on the total weight of the fluorine-free foam fire extinguishing agent, the content of the water is 50-80 wt %.

[0060] The present invention does not limit the specific preparation steps of the fluorine-free foam fire extinguishing agent, as long as the raw materials are mixed evenly.

[0061] The fluorine-free foam fire extinguishing agent provided by the present invention is tested for fire extinguishing performance and anti-burning performance in accordance with the national standard GB15308-2006 "Foam Fire Extinguishing Agent". The fire extinguishing performance test is carried out in the fire extinguishing experimental system. The results show that the fire extinguishing time of the fluorine-free foam fire extinguishing agent is less than 3 minutes, and the 25% anti-burning time is greater than 10 minutes. Therefore, the fluorine-free foam fire extinguishing agent has excellent fire extinguishing performance and anti-burning ability, does not contain fluorine, has extremely low organic solvent content, is environmentally friendly, and has low cost. It has obvious competitive advantages in replacing traditional aqueous film-forming foam fire extinguishing agents in the petrochemical industry.

[0062] It is understandable that the fluorine-free foam fire extinguishing agent is a concentrated solution, and when used, it needs to be mixed with water to form a foam solution. The present invention does not limit the specific amount of water added. In a preferred embodiment, based on the total weight of the fluorine-free foam fire extinguishing agent and water as 100 parts by weight, the fluorine-free foam fire extinguishing agent is 2 to 8 parts by weight, and the water is 92 to 98 parts by weight. Most preferably, the weight ratio of the fluorine-free foam fire extinguishing agent to water is 6:94.

[0063] The present invention also provides a method for preparing the fluorine-free foam fire extinguishing agent as described above, the method comprising: mixing a hydrocarbon surfactant, a carboxyl-modified organic silicon surfactant and water.

[0064] In a preferred embodiment, the method comprises the following steps:

[0065] (1) mixing a hydrocarbon surfactant with a portion of water, and then adding a carboxyl-modified silicone surfactant to obtain a mixed solution A;

[0066] (2) mixing the organic solvent and the remaining water to obtain a mixed solution B;

[0067] (3) Mix the mixed solution B, the mixed solution A and the pH adjuster.

[0068] In the method of the present invention, the fluorine-free foam fire extinguishing agent further contains one or more of a corrosion inhibitor, a chelating agent and a preservative. The present invention does not limit the specific step of adding the above components. In a specific embodiment, the above components are added to step (2), that is, step (2) includes: mixing the corrosion inhibitor, the chelating agent, the organic solvent, the preservative and the remaining water.

[0069] The present invention will be described in detail below by way of examples, but the protection scope of the present invention is not limited thereto. The raw materials in the following examples are all commercially available unless otherwise specified.

[0070] In the following examples, hydroxy polyether modified organosiloxane was purchased from Zhejiang Runhe Silicone New Materials Co., Ltd., model RH-288; cocamidopropyl betaine was purchased from Qingdao Huayuan Polymer Co., Ltd., model CAB-35; alkyl polyglycoside was purchased from Qingdao Huayuan Polymer Co., Ltd., model APG0810; sodium dodecyl sulfate and sodium dodecylbenzene sulfonate were purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., batch numbers C2116183 and S108366, respectively; dodecyl dimethyl betaine, dodecyl dimethyl benzyl ammonium chloride, and fatty alcohol polyoxyethylene ether (model AEO-9) were purchased from Shanghai MacLean Biochemical Technology Co., Ltd.; 3-sulfopropyl dodecyl dimethyl betaine was purchased from Shanghai Myrel Biochemical Technology Co., Ltd.

[0071] In the following examples, the pH value determination method is carried out with reference to 5.5 "pH value" in GB 15308-2006 "Foam Fire Extinguishing Agents".

[0072] Example 1

[0073] This example is used to illustrate the fluorine-free foam fire extinguishing agent and its preparation method according to the present invention.

[0074] Preparation of carboxyl-modified silicone surfactants:

[0075] A1. Mix 50 g of hydroxy polyether-modified organosiloxane and 50 g of maleic anhydride in 20 g of isopropanol, and react at 85° C. for 4.5 h to obtain a reaction solution.

[0076] A2. Cooling the reaction solution to room temperature, then transferring the solution to a rotary evaporator, and purifying and recovering the product by vacuum distillation to obtain a carboxyl-modified organosilicon surfactant.

[0077] Preparation of fluorine-free foam fire extinguishing agent:

[0078] (1) Under stirring conditions, 5 g of anionic hydrocarbon surfactant (sodium lauryl sulfate) was dissolved in 20 g of deionized water, and then 14.5 g of amphoteric hydrocarbon surfactant (cocamidopropyl betaine) and 8.5 g of nonionic hydrocarbon surfactant (alkyl glucoside) were added and mixed, and then 4.5 g of carboxyl-modified silicone surfactant was added to obtain a mixed solution A;

[0079] (2) 0.4 g of corrosion inhibitor (sodium tripolyphosphate), 1 g of chelating agent (disodium ethylenediaminetetraacetic acid), 5 g of organic solvent (mixed by diethylene glycol butyl ether and ethylene glycol in a weight ratio of 3:2) and 0.6 g of preservative (sodium benzoate) were dissolved in 37.5 g of deionized water and stirred to obtain a mixed solution B;

[0080] (3) adding the mixed solution A to the mixed solution B and stirring for 30 minutes to obtain a first solution;

[0081] (4) Add 3 g of pH adjuster (a citric acid aqueous solution with a mass concentration of 40%) to the first solution, and continue stirring for 30 min to obtain a fluorine-free foam fire extinguishing agent with a pH value of 7.0 to 9.5.

[0082] Example 2

[0083] This example is used to illustrate the fluorine-free foam fire extinguishing agent and its preparation method according to the present invention.

[0084] (1) preparing a carboxyl-modified organosilicon surfactant according to the method described in Example 1;

[0085] (2) Under stirring, 5 g of anionic hydrocarbon surfactant (sodium dodecyl sulfate) was dissolved in 20 g of deionized water, and then 12 g of amphoteric hydrocarbon surfactant (cocamidopropyl betaine) and 8 g of nonionic hydrocarbon surfactant (alkyl glucoside) were added and mixed, and then 3 g of carboxyl-modified silicone surfactant was added to obtain a mixed solution A;

[0086] (3) dissolving 0.4 g of corrosion inhibitor (sodium tripolyphosphate), 1 g of chelating agent (disodium ethylenediaminetetraacetic acid), 5 g of organic solvent (ethylene glycol) and 0.6 g of preservative (sodium benzoate) in 41.8 g of deionized water, stirring evenly to obtain a mixed solution B;

[0087] (4) adding the mixed solution A to the mixed solution B and stirring for 30 minutes to obtain a first solution;

[0088] (5) Add 3.2 g of a pH adjuster (a citric acid aqueous solution with a mass concentration of 40%) to the first solution, and continue stirring for 30 min to obtain a fluorine-free foam fire extinguishing agent with a pH value of 7.0 to 9.5.

[0089] Example 3

[0090] This example is used to illustrate the fluorine-free foam fire extinguishing agent and its preparation method according to the present invention.

[0091] (1) preparing a carboxyl-modified organosilicon surfactant according to the method described in Example 1;

[0092] (2) Under stirring conditions, 5 g of anionic hydrocarbon surfactant (sodium dodecyl sulfate) was dissolved in 20 g of deionized water, and then 20 g of nonionic hydrocarbon surfactant (alkyl polyglycoside) was added and mixed, and then 3 g of carboxyl-modified silicone surfactant was added to obtain a mixed solution A;

[0093] (3) 0.4 g of corrosion inhibitor (sodium hexametaphosphate), 1 g of chelating agent (disodium ethylenediaminetetraacetic acid), 7 g of organic solvent (mixed by diethylene glycol butyl ether and ethylene glycol in a weight ratio of 3:4) and 0.4 g of preservative (sodium benzoate) were dissolved in 39.9 g of deionized water and stirred to obtain a mixed solution B;

[0094] (4) adding the mixed solution A to the mixed solution B and stirring for 30 minutes to obtain a first solution;

[0095] (5) Add 3.3 g of pH adjuster (a citric acid aqueous solution with a mass concentration of 40%) to the first solution, and continue stirring for 30 min to obtain a fluorine-free foam fire extinguishing agent with a pH value of 7.0 to 9.5.

[0096] Example 4

[0097] This example is used to illustrate the fluorine-free foam fire extinguishing agent and its preparation method according to the present invention.

[0098] (1) preparing a carboxyl-modified organosilicon surfactant according to the method described in Example 1;

[0099] (2) Under stirring conditions, 3 g of anionic hydrocarbon surfactant (sodium dodecyl sulfate) was dissolved in 20 g of deionized water, and then 10 g of amphoteric hydrocarbon surfactant (cocamidopropyl betaine) and 10 g of nonionic hydrocarbon surfactant (alkyl glucoside) were added and mixed, and then 1 g of carboxyl-modified silicone surfactant was added to obtain a mixed solution A;

[0100] (3) 0.8 g of corrosion inhibitor (sodium tripolyphosphate), 3.0 g of chelating agent (disodium ethylenediaminetetraacetic acid), 3 g of organic solvent (mixed by diethylene glycol butyl ether and ethylene glycol in a weight ratio of 3:4) and 0.7 g of preservative (sodium benzoate) were dissolved in 42.5 g of deionized water and stirred to obtain a mixed solution B;

[0101] (4) adding the mixed solution A to the mixed solution B and stirring for 30 minutes to obtain a first solution;

[0102] (5) Add 6 g of pH adjuster (a citric acid aqueous solution with a mass concentration of 40%) to the first solution, and continue stirring for 30 min to obtain a fluorine-free foam fire extinguishing agent with a pH value of 7.0 to 9.5.

[0103] Example 5

[0104] This example is used to illustrate the fluorine-free foam fire extinguishing agent and its preparation method according to the present invention.

[0105] (1) preparing a carboxyl-modified organosilicon surfactant according to the method described in Example 1;

[0106] (2) Under stirring conditions, 3 g of a cationic hydrocarbon surfactant (dodecyl dimethyl benzyl ammonium chloride) was dissolved in 15 g of deionized water, and then 15 g of an amphoteric hydrocarbon surfactant (dodecyl dimethyl betaine) and 5 g of a nonionic hydrocarbon surfactant (alkyl glucoside) were added and mixed, and then 4 g of a carboxyl-modified silicone surfactant was added to obtain a mixed solution A;

[0107] (3) 0.4 g of corrosion inhibitor (sodium tripolyphosphate), 1 g of chelating agent (disodium ethylenediaminetetraacetic acid), 6 g of organic solvent (mixed by diethylene glycol butyl ether and isobutanol in a weight ratio of 3:3) and 0.6 g of preservative (sodium benzoate) were dissolved in 45.5 g of deionized water and stirred to obtain a mixed solution B;

[0108] (4) adding the mixed solution A to the mixed solution B and stirring for 30 minutes to obtain a first solution;

[0109] (5) Add 4.5 g of a pH adjuster (a citric acid aqueous solution with a mass concentration of 40%) to the first solution, and continue stirring for 30 min to obtain a fluorine-free foam fire extinguishing agent with a pH value of 7.0 to 9.5.

[0110] Example 6

[0111] This example is used to illustrate the fluorine-free foam fire extinguishing agent and its preparation method according to the present invention.

[0112] (1) preparing a carboxyl-modified organosilicon surfactant according to the method described in Example 1;

[0113] (2) Under stirring conditions, 3 g of anionic hydrocarbon surfactant (sodium dodecyl sulfate) was dissolved in 15 g of deionized water, and then 5 g of amphoteric hydrocarbon surfactant (cocamidopropyl betaine) and 10 g of nonionic hydrocarbon surfactant (alkyl glucoside) were added and mixed, and then 3 g of carboxyl-modified silicone surfactant was added to obtain a mixed solution A;

[0114] (3) 0.4 g of corrosion inhibitor (sodium tripolyphosphate), 2.5 g of chelating agent (disodium ethylenediaminetetraacetic acid), 4 g of organic solvent (mixed by isobutyl alcohol and ethylene glycol in a weight ratio of 2:2) and 0.6 g of preservative (sodium benzoate) were dissolved in 48.5 g of deionized water and stirred to obtain a mixed solution B;

[0115] (4) adding the mixed solution A to the mixed solution B and stirring for 30 minutes to obtain a first solution;

[0116] (5) Add 8 g of pH adjuster (a citric acid aqueous solution with a mass concentration of 40%) to the first solution, and continue stirring for 45 min to obtain a fluorine-free foam fire extinguishing agent with a pH value of 7.0 to 9.5.

[0117] Example 7

[0118] This example is used to illustrate the fluorine-free foam fire extinguishing agent and its preparation method according to the present invention.

[0119] Preparation of carboxyl-modified silicone surfactants:

[0120] A1. Mix 50 g of hydroxy polyether-modified organosiloxane and 150 g of maleic anhydride in 80 g of isopropanol, and react at 90° C. for 3 h to obtain a reaction solution.

[0121] A2. Cooling the reaction solution to room temperature, then transferring the solution to a rotary evaporator, and purifying and recovering the product by vacuum distillation to obtain a carboxyl-modified organosilicon surfactant.

[0122] Preparation of fluorine-free foam fire extinguishing agent:

[0123] (1) Under stirring conditions, 5 g of anionic hydrocarbon surfactant (sodium dodecyl sulfate) was dissolved in 20 g of deionized water, and then 10 g of amphoteric hydrocarbon surfactant (cocamidopropyl betaine) and 10 g of nonionic hydrocarbon surfactant (alkyl glucoside) were added and mixed, and then 1.5 g of carboxyl-modified silicone surfactant was added to obtain a mixed solution A;

[0124] (2) 0.6 g of corrosion inhibitor (sodium tripolyphosphate), 1.5 g of chelating agent (disodium ethylenediaminetetraacetic acid), 5 g of organic solvent (mixed by diethylene glycol butyl ether and ethylene glycol in a weight ratio of 3:2) and 0.6 g of preservative (potassium sorbate) were dissolved in 40 g of deionized water and stirred to obtain a mixed solution B;

[0125] (3) adding the mixed solution A to the mixed solution B and stirring for 30 minutes to obtain a first solution;

[0126] (4) Add 5.8 g of pH adjuster (mass concentration of 20% phosphoric acid) to the first solution and continue stirring for 30 min to obtain a fluorine-free foam fire extinguishing agent with a pH value of 7.0 to 9.5.

[0127] Example 8

[0128] This example is used to illustrate the fluorine-free foam fire extinguishing agent and its preparation method according to the present invention.

[0129] Preparation of carboxyl-modified silicone surfactants:

[0130] A1. Mix 60 g of hydroxy polyether-modified organosiloxane and 40 g of maleic anhydride in 25 g of isopropanol under stirring, and react at 60° C. for 8 h to obtain a reaction solution;

[0131] A2. Cooling the reaction solution to room temperature, then transferring the solution to a rotary evaporator, and purifying and recovering the product by vacuum distillation to obtain a carboxyl-modified organosilicon surfactant.

[0132] Preparation of fluorine-free foam fire extinguishing agent:

[0133] (1) Under stirring conditions, 12 g of anionic hydrocarbon surfactant (mixed with sodium dodecyl sulfate and sodium α-olefin sulfonate in a weight ratio of 2:1) was dissolved in 40 g of deionized water, and then 8 g of nonionic hydrocarbon surfactant (alkyl polyglycoside) was added and mixed, and then 2.0 g of carboxyl-modified silicone surfactant was added to obtain a mixed solution A;

[0134] (2) 0.4 g of corrosion inhibitor (sodium tripolyphosphate), 1 g of chelating agent (disodium ethylenediaminetetraacetic acid), 4 g of organic solvent (mixed by diethylene glycol butyl ether and ethylene glycol in a weight ratio of 2:2) and 0.6 g of preservative (sodium benzoate) were dissolved in 26.0 g of deionized water and stirred to obtain a mixed solution B;

[0135] (3) adding the mixed solution A to the mixed solution B and stirring for 30 minutes to obtain a first solution;

[0136] (4) Add 6 g of pH adjuster (phosphoric acid with a mass concentration of 20%) to the first solution and continue stirring for 30 min to obtain a fluorine-free foam fire extinguishing agent with a pH value of 7.0 to 9.5.

[0137] Example 9

[0138] The method described in Example 1 is followed, except that the carboxyl-modified organic silicon surfactant is prepared according to the following method: A1, 60 g of hydroxy polyether-modified organic silicon oxane and 100 g of maleic anhydride are mixed in 35 g of isopropanol under stirring, and reacted at 75° C. for 3 h to obtain a reaction solution;

[0139] A2. Cooling the reaction solution to room temperature, then transferring the solution to a rotary evaporator, and purifying and recovering the product by vacuum distillation to obtain a carboxyl-modified organosilicon surfactant.

[0140] Example 10

[0141] This example is used to illustrate the fluorine-free foam fire extinguishing agent and its preparation method according to the present invention.

[0142] Preparation of carboxyl-modified silicone surfactants:

[0143] A1. Mix 60 g of hydroxy polyether-modified organosiloxane and 80 g of maleic anhydride in 20 g of isopropanol, and react at 80° C. for 3 h to obtain a reaction solution;

[0144] A2. Cooling the reaction solution to room temperature, then transferring the solution to a rotary evaporator, and purifying and recovering the product by vacuum distillation to obtain a carboxyl-modified organosilicon surfactant.

[0145] Preparation of fluorine-free foam fire extinguishing agent:

[0146] (1) Under stirring conditions, 4 g of a cationic hydrocarbon surfactant (dodecyl dimethyl benzyl ammonium chloride) was dissolved in 20 g of deionized water, and then 8 g of an amphoteric hydrocarbon surfactant (cocamidopropyl betaine) and 8 g of a nonionic hydrocarbon surfactant (mixed with an alkyl glycoside and a fatty alcohol polyoxyethylene ether in a weight ratio of 3:1) were added and mixed, and then 2.5 g of a carboxyl-modified silicone surfactant was added to obtain a mixed solution A;

[0147] (2) dissolving 0.4 g of corrosion inhibitor (sodium tripolyphosphate), 1 g of chelating agent (disodium ethylenediaminetetraacetic acid), 3 g of organic solvent (butyl diglycol) and 0.6 g of preservative (sodium benzoate) in 46 g of deionized water, stirring evenly to obtain a mixed solution B;

[0148] (3) adding the mixed solution A to the mixed solution B and stirring for 30 minutes to obtain a first solution;

[0149] (4) Add 6.5 g of pH adjuster (a citric acid aqueous solution with a mass concentration of 40%) to the first solution, and continue stirring for 50 min to obtain a fluorine-free foam fire extinguishing agent with a pH value of 7.0 to 9.5.

[0150] Comparative Example 1

[0151] The method described in Example 1 was used for implementation, except that unmodified organosilicon surfactant was added when preparing the fluorine-free foam fire extinguishing agent;

[0152] That is, in step (1), the carboxyl-modified organic silicon surfactant is replaced by a hydroxy polyether-modified organic siloxane.

[0153] Comparative Example 2

[0154] The method described in Example 1 is used for implementation, except that when preparing the fluorine-free foam fire extinguishing agent, the hydrocarbon surfactant is only an anionic hydrocarbon surfactant;

[0155] That is, step (1) comprises: dissolving 28 g of anionic hydrocarbon surfactant (sodium dodecyl sulfate) in 20 g of deionized water, and then adding 4.5 g of carboxyl-modified silicone surfactant to obtain a mixed solution A.

[0156] Test Example 1

[0157] The hydroxy polyether modified organosiloxane in Example 1 and the prepared carboxyl modified organosilicon surfactant were subjected to nuclear magnetic resonance detection. The results are as follows: Figure 1 As shown, Figure 1 In the above-mentioned, A is a carboxyl-modified organic silicon surfactant, and B is a hydroxyl polyether-modified organic siloxane.

[0158] Depend on Figure 1 It can be seen that the carboxyl-modified organosilicon surfactant has H on C connected to the carboxyl group at the 6.39ppm shift, and no H on C directly connected to the hydroxyl group is seen at the 3.22ppm shift. In addition, the positions of the hydrogen spectrum peaks of the organosilicon surfactant before and after carboxyl modification are consistent. The above results show that the nuclear magnetic resonance results are consistent with the theoretically designed structure, and the present invention successfully prepares a carboxyl-modified organosilicon surfactant containing a carboxyl functional group using hydroxy polyether-modified organosiloxane and maleic anhydride.

[0159] Test Example 2

[0160] The fluorine-free foam fire extinguishing agents prepared in Examples 1-10 and Comparative Examples 1-2 were tested for foam performance, fire extinguishing performance and anti-burning performance. The test results are shown in Table 1 below.

[0161] Equipment used during the test: foam generation system, foam collector, liquid analysis device, balance, stopwatch, round, conical bottom steel oil pan (inner diameter: 565mm, depth 150mm, oil pan area 0.25m 2 ), steel fire-resistant tank (inner diameter 120mm, depth 80mm).

[0162] Determination method of foaming multiple and 25% liquid separation time: refer to 5.8 "Foaming multiple and 25% liquid separation time of low-expansion foam liquid" in GB 15308-2006 "Foam Fire Extinguishing Agent".

[0163] The specific steps of the fire extinguishing performance and anti-burning performance test are as follows: (1) First, the fire extinguishing agent product and water are mixed into a foam solution in a ratio of 6:94 and filled into a foam solution storage tank; (2) Apply a pressure of (0.7±0.03)MPa to the foam solution storage tank and adjust the 7mm flow regulating head so that the vertical foam flow rate is (725~775)g / min; (3) Adjust the position of the foam gun so that the applied foam falls exactly in the center of the oil pan; (4) Add 9L of fuel ( 120# solvent oil for rubber industry), add 1L of fuel to the anti-burn tank and place it on the leeward side of the oil pan; (5) After adding the fuel, ignite the oil pan within 5 minutes, pre-burn for 60 seconds, and start to supply foam; (6) Record the moment when the flame is completely extinguished, which is the fire extinguishing time; (7) Continue to apply foam after the flame is extinguished, and stop supplying foam after the total foam supply time reaches 180 seconds, wait for 60 seconds, place the anti-burn tank containing 1L of fuel in the center of the oil pan and ignite it, and record the 25% anti-burn time.

[0164] Table 1

[0165]

[0166] It can be seen from Table 1 that the fluorine-free foam fire extinguishing agents prepared in Examples 1-10 of the present invention have excellent foaming multiples, a long 25% liquid separation time, a fire extinguishing time of less than 3 minutes, and a 25% anti-burning time of more than 10 minutes, indicating that the fluorine-free foam fire extinguishing agent provided by the present invention has excellent foaming performance, fire extinguishing performance and anti-burning performance.

[0167] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A fluorine-free foam fire extinguishing agent, characterized in that: The fluorine-free foam fire extinguishing agent contains a hydrocarbon surfactant, a carboxyl-modified silicone surfactant, an organic solvent, water, and an optional pH regulator; Wherein, the carboxyl-modified organosilicon surfactant is obtained by modifying the organosilicon surfactant with maleic anhydride; The hydrocarbon surfactant is selected from at least two of anionic hydrocarbon surfactants, cationic hydrocarbon surfactants, amphoteric hydrocarbon surfactants and nonionic hydrocarbon surfactants.

2. The fluorine-free foam fire extinguishing agent according to claim 1, characterized in that: The carboxyl-modified silicone surfactant is prepared according to the following process: The organic silicon surfactant, maleic anhydride and isopropanol are mixed and stirred, reacted at 60-90° C. for 2-8 hours, and then cooled and purified.

3. The fluorine-free foam fire extinguishing agent according to claim 1 or 2, characterized in that: The organosilicon surfactant is selected from one or more of hydroxy polyether modified organosilicon oxane, terminal hydroxyl organosilicon block polyether, hydroxy acrylic organosilicon and hydroxy polyester organosilicon.

4. The fluorine-free foam fire extinguishing agent according to claim 2 or 3, characterized in that: The weight ratio of the organic silicon surfactant to maleic anhydride is 1:0.5-3.

5. The fluorine-free foam fire extinguishing agent according to claim 2, characterized in that: The weight ratio of the isopropanol to the total weight of the organosilicon surfactant and maleic anhydride is 10-40:

100.

6. The fluorine-free foam fire extinguishing agent according to claim 1, characterized in that: Based on the total weight of the fluorine-free foam fire extinguishing agent, the content of the hydrocarbon surfactant is 5-35wt%, the content of the carboxyl-modified silicone surfactant is 0.5-5wt%, the content of the organic solvent is 1-8wt%, and the content of the pH regulator is 0.1-10wt%.

7. The fluorine-free foam fire extinguishing agent according to claim 1, characterized in that: The anionic hydrocarbon surfactant is selected from one or more of sodium dodecyl sulfate, sodium dodecylbenzene sulfonate, sodium fatty alcohol polyoxyethylene ether sulfate and sodium α-olefin sulfonate; Preferably, the cationic hydrocarbon surfactant is selected from one or more of dodecyl dimethyl benzyl ammonium chloride and polyoxyethylene alkyl amide; Preferably, the amphoteric hydrocarbon surfactant is selected from one or more of cocamidopropyl betaine, dodecyl dimethyl betaine, 3-sulfopropyl dodecyl dimethyl betaine and 2-undecyl-N-acetoxy-N(2-hydroxyethyl)imidazoline; Preferably, the nonionic hydrocarbon surfactant is selected from one or more of alkyl glycosides, fatty alcohol polyoxyethylene ethers and alkylphenol polyoxyethylene ethers.

8. The fluorine-free foam fire extinguishing agent according to claim 1, characterized in that: The organic solvent is selected from one or more of ethylene glycol, diethylene glycol butyl ether and isobutyl alcohol; Preferably, the pH adjuster is selected from one or more of citric acid, lactic acid, tartaric acid, malic acid, phosphoric acid and acetic acid.

9. The fluorine-free foam fire extinguishing agent according to claim 1, characterized in that: The fluorine-free foam fire extinguishing agent further contains one or more of a corrosion inhibitor, a chelating agent and a preservative.

10. The fluorine-free foam fire extinguishing agent according to claim 9, characterized in that: The corrosion inhibitor is selected from one or more of benzotriazole, sodium tripolyphosphate, and sodium hexametaphosphate; Preferably, the chelating agent is disodium ethylenediaminetetraacetate; Preferably, the preservative is selected from one or more of sodium benzoate, potassium sorbate and methyl paraben.

11. The fluorine-free foam fire extinguishing agent according to claim 1 or 9, characterized in that: Calculated by weight percentage, the fluorine-free foam fire extinguishing agent contains: 5-35wt% hydrocarbon surfactant, 0.5-5wt% carboxyl modified silicone surfactant, 1-8wt% organic solvent, 0.1-1wt% corrosion inhibitor, 0.5-3wt% chelating agent, 0.1-1wt% preservative and 0.1-10wt% pH regulator.

12. A method for preparing the fluorine-free foam fire extinguishing agent according to any one of claims 1 to 11, characterized in that: The method comprises: mixing a hydrocarbon surfactant, a carboxyl-modified organic silicon surfactant, an organic solvent and water.

13. The method according to claim 12, characterized in that The method comprises the following steps: (1) mixing a hydrocarbon surfactant with a portion of water, and then adding a carboxyl-modified silicone surfactant to obtain a mixed solution A; (2) mixing the organic solvent and the remaining water to obtain a mixed solution B; (3) Mix the mixed solution B, the mixed solution A and the pH adjuster.

14. The method according to claim 13, characterized in that Step (2) comprises: mixing the corrosion inhibitor, the chelating agent, the organic solvent, the preservative and the remaining water.

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