Aqueous film-forming foam extinguishing agent and preparation method thereof

Abstract

The invention relates to the technical field of fire extinguishing agents, and discloses an aqueous film-forming foam fire extinguishing agent and a preparation method thereof.The aqueous film-forming foam fire extinguishing agent comprises a short-chain fluorocarbon surfactant, a hydrocarbon surfactant, a carboxyl modified organosilicon surfactant, a cosolvent and a pH regulator; the carboxyl modified organosilicon surfactant is obtained by modifying a hydroxyl-containing organosilicon surfactant with maleic anhydride. The short-chain fluorocarbon surfactant and the carboxyl modified organic silicon surfactant are compounded, the hydrocarbon surfactant, the cosolvent and the pH regulator are added, and the aqueous film-forming foam extinguishing agent which is high in surface activity, high in foaming and foam stabilizing capacity and excellent in fire extinguishing performance and does not contain PFOS is obtained by utilizing the synergistic interaction effect of the multiple components.

Description

Technical Field

[0001] The invention relates to the technical field of fire extinguishing agents, and in particular to an aqueous film-forming foam fire extinguishing agent and a preparation method thereof. Background Art

[0002] Aqueous film-forming foam fire extinguishing agent, also known as "light water" foam fire extinguishing agent, refers to a fire extinguishing agent that can form a layer of water film on the fuel surface during the fire extinguishing process. This water film can not only isolate the fuel surface from oxygen, but also cool the fuel surface; at the same time, the liquid precipitated from the foam evaporates into water vapor at high temperature, diluting the oxygen concentration above the flammable liquid. Due to the synergistic fire extinguishing effect of water film and foam, aqueous film-forming foam is particularly suitable for large-scale flammable liquid fires. It is widely used in large ships, offshore oil and gas drilling platforms, and oil tank areas.

[0003] Perfluorooctane sulfonate (PFOS) and perfluorooctane sulfonic acid (PFOA) are widely used in aqueous film-forming foam fire extinguishing agents (AFFF) due to their high surface activity, high chemical stability, and high thermal stability. However, because PFOS and PFOA are difficult to degrade and pose serious ecological hazards and environmental pollution problems, countries around the world have formulated increasingly stringent environmental regulations to restrict the use of PFOS.

[0004] Therefore, it is of great research significance to strengthen the control of PFOS and develop efficient and environmentally friendly PFOS-free aqueous film-forming foam fire extinguishing agents. Summary of the invention

[0005] The purpose of the present invention is to overcome the problem that the aqueous film-forming foam fire extinguishing agent in the prior art contains highly polluting raw material components such as PFOS and PFOA, and to provide an aqueous film-forming foam fire extinguishing agent and a preparation method thereof.

[0006] In order to achieve the above object, the present invention provides an aqueous film-forming foam fire extinguishing agent, wherein the aqueous film-forming foam fire extinguishing agent contains: a short-chain fluorocarbon surfactant, a hydrocarbon surfactant, a carboxyl-modified silicone surfactant, a cosolvent and a pH regulator;

[0007] Wherein, the carboxyl-modified silicone surfactant is obtained by modifying a hydroxyl-containing silicone surfactant with maleic anhydride;

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

[0009] Preferably, the aqueous film-forming foam fire extinguishing agent contains, in percentage, 0.5-2 wt% of a short-chain fluorocarbon surfactant, 10-30 wt% of a hydrocarbon surfactant, 0.5-2 wt% of a carboxyl-modified silicone surfactant, 1-4 wt% of a cosolvent, and 0.1-8 wt% of a pH regulator;

[0010] Wherein, the carboxyl-modified silicone surfactant is obtained by modifying a hydroxyl-containing silicone surfactant with maleic anhydride;

[0011] The hydrocarbon surfactant is selected from at least two of anionic hydrocarbon surfactants, amphoteric hydrocarbon surfactants and nonionic hydrocarbon surfactants.

[0012] Preferably, the carboxyl-modified silicone surfactant is prepared according to the following process:

[0013] The hydroxyl-containing organosilicon surfactant, maleic anhydride and organic solvent are mixed and stirred, reacted at 60-90° C. for 2-8 hours, and then cooled and purified.

[0014] Preferably, the weight ratio of the hydroxyl-containing silicone surfactant to maleic anhydride is 1:0.5-3.

[0015] Preferably, the hydroxyl-containing silicone surfactant is selected from one or more of hydroxyl polyether-modified silicone siloxane, hydroxyl-terminated silicone block polyether, hydroxyl acrylic silicone and hydroxyl polyester silicone.

[0016] Preferably, the ratio of the weight of the organic solvent to the total weight of the hydroxyl-containing organosilicon surfactant and maleic anhydride is 10-40:100.

[0017] Preferably, the organic solvent is selected from any one of isopropanol, n-propanol, propylene glycol, 1,3-butanediol and pentanediol.

[0018] 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.

[0019] Preferably, the amphoteric hydrocarbon surfactant is selected from one or more of cocamidopropyl betaine, dodecyl dimethyl betaine, N-dodecyl dimethyl betaine and 2-undecyl-N-acetoxy-N(2-hydroxyethyl)imidazoline.

[0020] Preferably, the nonionic hydrocarbon surfactant is an alkyl glycoside.

[0021] Preferably, the short-chain fluorocarbon surfactant is selected from one or more of perfluoroalkylamine oxides, perfluoroalkyl polyoxyethylene ethers, perfluoroalkyl ether betaines, and hexafluoropropylene oxide trimer quaternary ammonium salts.

[0022] Preferably, the co-solvent is selected from one or more of ethylene glycol, diethylene glycol butyl ether and isobutyl alcohol.

[0023] Preferably, the pH adjuster is selected from one or more of citric acid, lactic acid, tartaric acid, malic acid, phosphoric acid and acetic acid.

[0024] Preferably, the aqueous film-forming foam fire extinguishing agent further contains one or more of an antifreeze agent, a corrosion inhibitor, a chelating agent, a flame retardant and a preservative.

[0025] Preferably, the antifreeze agent is selected from one or more of urea, ethylene glycol and propanol.

[0026] Preferably, the corrosion inhibitor is selected from one or more of sodium chromate, potassium chromate, sodium tripolyphosphate and sodium hexametaphosphate.

[0027] Preferably, the chelating agent is disodium ethylenediaminetetraacetate.

[0028] Preferably, the flame retardant is selected from one or more of potassium bicarbonate, sodium bicarbonate, diammonium hydrogen phosphate, ammonium polyphosphate, and diammonium dihydrogen phosphate.

[0029] Preferably, the preservative is selected from one or more of sodium benzoate, potassium sorbate and methyl paraben.

[0030] Preferably, in percentage, the content of the antifreeze agent is 2-10wt%, the content of the corrosion inhibitor is 0.1-1wt%, the content of the chelating agent is 0.1-1wt%, the content of the flame retardant is 1-8wt%, and the content of the preservative is 0.1-3wt%.

[0031] The second aspect of the present invention provides a method for preparing the aqueous film-forming foam fire extinguishing agent as described above, the method comprising: mixing a hydrocarbon surfactant, a short-chain fluorocarbon surfactant, a carboxyl-modified silicone surfactant, a cosolvent, a pH regulator and water.

[0032] Preferably, the method specifically comprises:

[0033] (1) Mixing a hydrocarbon surfactant with a portion of water under stirring, and then adding a short-chain fluorocarbon surfactant and a carboxyl-modified silicone surfactant to obtain a mixed solution A;

[0034] (2) mixing and stirring the antifreeze agent, the corrosion inhibitor, the chelating agent, the flame retardant, the preservative, the cosolvent and the remaining water to obtain a mixed solution B;

[0035] (3) The mixed solution A and the mixed solution B are mixed and stirred, and then a pH adjuster is added.

[0036] In the present invention, maleic anhydride is used to modify a hydroxyl-containing organosilicon surfactant, thereby improving the water solubility of the organosilicon surfactant without affecting its surface activity; at the same time, a short-chain fluorocarbon surfactant is compounded with a carboxyl-modified organosilicon surfactant, and a hydrocarbon surfactant, a cosolvent and a pH regulator are added, and the synergistic effect between the multiple components is utilized to obtain a PFOS-free water-film-forming foam fire extinguishing agent with high surface activity, strong foaming and stabilizing ability, and excellent fire extinguishing performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 FT-IR spectra of the carboxyl-modified organosilicon surfactant (a) and the hydroxyl-containing organosilicon surfactant (b) in Example 1 of the present invention. DETAILED DESCRIPTION

[0038] 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.

[0039] 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.

[0040] The present invention provides an aqueous film-forming foam fire extinguishing agent, which contains: a short-chain fluorocarbon surfactant, a hydrocarbon surfactant, a carboxyl-modified organic silicon surfactant, a cosolvent and a pH regulator; wherein the carboxyl-modified organic silicon surfactant is obtained by modifying a hydroxyl-containing organic silicon surfactant with maleic anhydride; and the hydrocarbon surfactant is selected from at least two of anionic hydrocarbon surfactants, amphoteric hydrocarbon surfactants and nonionic hydrocarbon surfactants.

[0041] In a preferred embodiment, the aqueous film-forming foam fire extinguishing agent contains, in percentage, 0.5-2wt% of a short-chain fluorocarbon surfactant, 10-30wt% of a hydrocarbon surfactant, 0.5-2wt% of a carboxyl-modified silicone surfactant, 1-4wt% of a cosolvent and 0.1-8wt% of a pH adjuster, with the remainder being water.

[0042] More preferably, the aqueous film-forming foam fire extinguishing agent contains, in percentage terms: 1-2 wt% of a short-chain fluorocarbon surfactant, 15-28 wt% of a hydrocarbon surfactant, 0.5-2 wt% of a carboxyl-modified silicone surfactant, 1-4 wt% of a cosolvent and 0.8-8 wt% of a pH adjuster, with the remainder being water.

[0043] The present invention uses a short-chain fluorocarbon surfactant and a carboxyl-modified organosilicon surfactant to compound, and adds a hydrocarbon surfactant, a cosolvent and a pH regulator, and utilizes the synergistic effect between multiple components. In this way, the amount of cosolvent and short-chain fluorocarbon surfactant used is extremely small, and a PFOS-free aqueous film-forming foam fire extinguishing agent with high surface activity, strong foaming and stabilizing ability, and excellent fire extinguishing performance can be obtained. Therefore, the aqueous film-forming foam fire extinguishing agent provided by the present invention has low cost, good environmental protection, and excellent fire extinguishing performance, and has obvious competitive advantages in replacing traditional aqueous film-forming foam fire extinguishing agents in the petrochemical industry.

[0044] The silane group and siloxane group with strong hydrophobic effect make the organosilicon surfactant have high surface activity, so that the surface tension of water can be greatly reduced. In addition, the organosilicon surfactant also has obvious advantages in terms of stability, wettability, spreadability, etc., but its water solubility is poor, which limits its application. At present, the water solubility of organosilicon surfactants is improved by using a large amount of organic solvents, but the use of a large amount of organic solvents is not conducive to efficient fire extinguishing, and will increase production costs and reduce environmental protection. In the present invention, a specific hydroxyl-containing organosilicon surfactant is first selected, and then maleic anhydride (maleic anhydride) is used to modify it, so that the water solubility and surface activity of the obtained carboxyl-modified organosilicon surface solvent are good.

[0045] In a specific embodiment, the carboxyl-modified silicone surfactant is prepared according to the following process: a hydroxyl-containing silicone surfactant, maleic anhydride and an organic solvent are mixed and stirred, then reacted, and then cooled and purified. 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, 4.5h, 5h, 6h, 7h or 8h. In the present invention, the purification is carried out by vacuum distillation.

[0046] In the present invention, the weight ratio of the hydroxyl-containing organic silicon surfactant to maleic anhydride is 1:0.5-3.

[0047] In a preferred embodiment, the organic solvent is selected from any one of isopropanol, n-propanol, propylene glycol, 1,3-butanediol and pentanediol.

[0048] In the present invention, the weight ratio of the organic solvent to the total weight of the hydroxyl-containing silicone surfactant and maleic anhydride is 10 to 40:100, specifically, for example, 10:100, 12:100, 15:100, 20:100, 22:100, 25:100, 30:100, 33:100, 35:100 or 40:100.

[0049] The present invention does not limit the specific selection of the hydroxyl-containing silicone surfactant. In a specific embodiment, the hydroxyl-containing silicone surfactant is selected from one or more of hydroxyl polyether-modified silicone siloxanes, terminal hydroxyl silicone block polyethers, hydroxyl acrylic silicones and hydroxyl polyester silicones, preferably hydroxyl polyether-modified silicone siloxanes.

[0050] Hydrocarbon surfactants are environmentally friendly and have good foaming properties, and are mainly used as foaming components of fire extinguishing agents. In order to make the foaming properties of the hydrocarbon surfactants better, in the present invention, the hydrocarbon surfactants are selected from at least two of anionic hydrocarbon surfactants, amphoteric hydrocarbon surfactants and nonionic hydrocarbon surfactants, preferably a mixture of anionic hydrocarbon surfactants, amphoteric hydrocarbon surfactants and nonionic hydrocarbon surfactants.

[0051] In a preferred embodiment, the anionic hydrocarbon surfactant may be one or more of sodium dodecyl sulfate, sodium dodecylbenzene sulfonate, sodium fatty alcohol polyoxyethylene ether sulfate and sodium α-olefin sulfonate.

[0052] In a preferred embodiment, the amphoteric hydrocarbon surfactant may be one or more of cocamidopropyl betaine, dodecyl dimethyl betaine, N-dodecyl dimethyl betaine and 2-undecyl-N-acetoxy-N(2-hydroxyethyl)imidazoline.

[0053] In a preferred embodiment, the nonionic hydrocarbon surfactant is an alkyl glycoside.

[0054] The present invention does not limit the specific type of the short-chain fluorocarbon surfactant, as long as it is a fluorocarbon surfactant with a fluorocarbon chain length of ≤ 6. In a preferred embodiment, the short-chain fluorocarbon surfactant is selected from one or more of perfluoroalkylamine oxide, perfluoroalkyl polyoxyethylene ether, perfluoroalkyl ether betaine, and hexafluoropropylene oxide trimer quaternary ammonium salt.

[0055] The present invention is not limited to the specific source of the perfluoroalkylamine oxide. In a preferred embodiment, the perfluoroalkylamine oxide is FS-50 fluorocarbon surfactant and / or 1157 fluorocarbon surfactant purchased from DuPont.

[0056] In the present invention, the co-solvent is selected from one or more of ethylene glycol, diethylene glycol butyl ether and isobutyl alcohol, so that it can not only play a dissolving effect, but also reduce the freezing point of the fire extinguishing agent product.

[0057] 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, and most preferably a citric acid aqueous solution with a mass concentration of 40%.

[0058] In order to make the fire extinguishing performance and anti-burning ability of the aqueous film-forming foam fire extinguishing agent better, in the present invention, the aqueous film-forming foam fire extinguishing agent also contains one or more of antifreeze agents, corrosion inhibitors, chelating agents, flame retardants and preservatives, and preferably also contains a mixture of antifreeze agents, corrosion inhibitors, chelating agents, flame retardants and preservatives.

[0059] In a preferred embodiment, in percentage, the content of the antifreeze agent is 2-10wt%, the content of the corrosion inhibitor is 0.1-1wt%, the content of the chelating agent is 0.1-1wt%, the content of the flame retardant is 1-8wt%, and the content of the preservative is 0.1-3wt%.

[0060] In a preferred embodiment, the antifreeze agent is selected from one or more of urea, ethylene glycol and propanol, preferably urea. Urea can not only reduce the freezing point of the fire extinguishing agent product, but also improve the burning resistance of the foam fire extinguishing agent.

[0061] The present invention does not limit the specific type of the corrosion inhibitor, for example, it can be chromate, polyethylene, polyphosphate or organophosphorus corrosion inhibitor. Preferably, the corrosion inhibitor is selected from one or more of sodium chromate, potassium chromate, sodium tripolyphosphate and sodium hexametaphosphate.

[0062] In order to reduce the cost of the chelating agent and make the raw materials readily available, in the present invention, the chelating agent is disodium ethylenediaminetetraacetate.

[0063] The addition of flame retardant can play a certain role in blocking the spread of fire and play an effective auxiliary role in fire extinguishing. In order to achieve better flame retardant effect, in the present invention, the flame retardant is selected from one or more of potassium bicarbonate, sodium bicarbonate, diammonium hydrogen phosphate, ammonium polyphosphate, and diammonium dihydrogen phosphate.

[0064] In the present invention, the preservative is selected from one or more of sodium benzoate, potassium sorbate and methyl parahydroxybenzoate.

[0065] In a preferred embodiment, the aqueous film-forming foam fire extinguishing agent contains a short-chain fluorocarbon surfactant, a hydrocarbon surfactant, a carboxyl-modified silicone surfactant, a cosolvent, a pH regulator, an antifreeze agent, a corrosion inhibitor, a chelating agent, a flame retardant, a preservative and water.

[0066] Further preferably, the aqueous film-forming foam fire extinguishing agent contains, in percentage: 0.5-2wt% of short-chain fluorocarbon surfactant, 10-30wt% of hydrocarbon surfactant, 0.5-2wt% of carboxyl-modified silicone surfactant, 1-4wt% of cosolvent, 0.1-8wt% of pH adjuster, 2-10wt% of antifreeze agent, 0.1-1wt% of corrosion inhibitor, 0.1-1wt% of chelating agent, 1-8wt% of flame retardant, 0.1-3wt% of preservative and 50-80wt% of water.

[0067] More preferably, the aqueous film-forming foam fire extinguishing agent contains, in percentage: 1-2wt% of short-chain fluorocarbon surfactant, 15-28wt% of hydrocarbon surfactant, 0.5-2wt% of carboxyl-modified silicone surfactant, 1-4wt% of cosolvent, 1-8wt% of pH regulator, 3-10wt% of antifreeze agent, 0.3-0.7wt% of corrosion inhibitor, 0.2-1wt% of chelating agent, 0.8-8wt% of flame retardant, 1-3wt% of preservative and 50-80wt% of water.

[0068] In the present invention, firstly, based on a hydroxyl-containing silicone surfactant, a hydrophilic group carboxyl is introduced from the molecular structure, and the silicone surfactant is chemically modified to obtain a carboxyl-modified silicone surfactant with high surface activity, strong hydrophilicity and strong foam stabilizing ability; then, the carboxyl-modified silicone surfactant is compounded with a short-chain fluorocarbon surfactant and a hydrocarbon surfactant, and raw material components such as a hydrocarbon surfactant, a cosolvent, a chelating agent, an antifreeze agent, a flame retardant, a corrosion inhibitor and a pH regulator are added, and the synergistic effect between the multiple components is utilized to obtain an aqueous film-forming foam fire extinguishing agent with excellent fire extinguishing performance and strong anti-burning ability.

[0069] The aqueous film-forming foam fire extinguishing agent provided by the present invention can not only avoid the use of PFOS while ensuring the fire extinguishing performance and the anti-burning ability, but also reduce the amount of short-chain fluorocarbon surfactants and co-solvents (organic solvents), thereby making the fire extinguishing agent lower in cost and more environmentally friendly.

[0070] In a preferred embodiment, the aqueous film-forming foam fire extinguishing agent is mixed with water before being used for fire extinguishing. 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.

[0071] The present invention also provides a method for preparing the aqueous film-forming foam fire extinguishing agent as described above, the method comprising: mixing a hydrocarbon surfactant, a short-chain fluorocarbon surfactant, a carboxyl-modified organic silicon surfactant, a cosolvent, a pH regulator and water.

[0072] In a preferred embodiment, the method comprises the following steps:

[0073] (1) Mixing a hydrocarbon surfactant with a portion of water under stirring, and then adding a short-chain fluorocarbon surfactant and a carboxyl-modified silicone surfactant to obtain a mixed solution A;

[0074] (2) mixing and stirring the antifreeze agent, the corrosion inhibitor, the chelating agent, the flame retardant, the preservative, the cosolvent and the remaining water to obtain a mixed solution B;

[0075] (3) The mixed solution A and the mixed solution B are mixed and stirred, and then a pH adjuster is added.

[0076] The present invention will be described in detail below through 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.

[0077] In the following examples, perfluoroalkylamine oxides were purchased from DuPont, model FS-50 and 1157; hydroxy polyether modified organosiloxane was purchased from Zhejiang Runhe Silicone New Materials Co., Ltd., model RH-288; maleic anhydride was purchased from Sane Chemical Technology (Shanghai) Co., Ltd.; 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 was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., batch numbers C2116183 respectively; dodecyl dimethyl betaine and sodium α-olefin sulfonate were purchased from Shanghai MacLean Biochemical Technology Co., Ltd.

[0078] Example 1

[0079] This example is used to illustrate the aqueous film-forming foam fire extinguishing agent and its preparation method according to the present invention.

[0080] Aqueous film-forming foam fire extinguishing agent: 2.0kg short-chain fluorocarbon surfactant (compounded by FS-50 and 1157 fluorocarbon surfactant in a weight ratio of 1:1), 22kg hydrocarbon surfactant (compounded by sodium lauryl sulfate, cocamidopropyl betaine and alkyl glucoside in a weight ratio of 4:9:9), 1.5kg carboxyl-modified silicone surfactant, 5kg antifreeze agent (urea), 0.3kg corrosion inhibitor (sodium tripolyphosphate), 0.2kg chelating agent (disodium ethylenediaminetetraacetic acid), 6kg flame retardant (compounded by diammonium phosphate and ammonium polyphosphate in a weight ratio of 1:1), 2kg cosolvent (butyl diethylene glycol), 1kg pH adjuster (aqueous solution of citric acid), 1kg preservative (sodium benzoate) and 59kg deionized water;

[0081] The carboxyl-modified silicone surfactant is prepared according to the following process: adding hydroxyl polyether-modified silicone siloxane and maleic anhydride to isopropanol in a weight ratio of 1:1, stirring evenly, and reacting at 85°C for 4.5 hours to obtain a reaction solution, wherein the ratio of the weight of isopropanol to the total weight of hydroxyl polyether-modified silicone siloxane and maleic anhydride is 20:100; cooling the reaction solution to room temperature, then transferring the solution to a rotary evaporator, and purifying and recovering the product by reduced pressure distillation to obtain a carboxyl-modified silicone surfactant.

[0082] The preparation method of the aqueous film-forming foam fire extinguishing agent comprises the following steps:

[0083] (1) Under stirring conditions, sodium lauryl sulfate is dissolved in 20 kg of deionized water, stirred evenly, then cocamidopropyl betaine and alkyl glucoside are added, then a fluorocarbon surfactant is added, stirred evenly, and finally a carboxyl-modified silicone surfactant is added to obtain a mixed solution A;

[0084] (2) dissolving the antifreeze agent, corrosion inhibitor, chelating agent, flame retardant, preservative and co-solvent in the remaining deionized water and stirring evenly to obtain a mixed solution B;

[0085] (3) Add mixed solution A to mixed solution B and stir for 30 minutes, then add pH adjuster and continue stirring for 30 minutes to obtain an aqueous film-forming foam fire extinguishing agent with a pH value between 70 and 9.5.

[0086] Example 2

[0087] The method described in Example 1 is used for implementation, except that the aqueous film-forming foam fire extinguishing agent includes: 2.0 kg FS-50 short-chain fluorocarbon surfactant, 20 kg hydrocarbon surfactant (compounded by sodium α-olefin sulfonate, cocamidopropyl betaine and alkyl glucoside in a weight ratio of 1:2:2), 1.5 kg carboxyl-modified silicone surfactant, 5 kg antifreeze agent (urea), 0.3 kg corrosion inhibitor (sodium tripolyphosphate), 0.2 kg chelating agent (disodium ethylenediaminetetraacetic acid), 6 kg flame retardant (compounded by diammonium phosphate and ammonium polyphosphate in a weight ratio of 1:1), 2 kg cosolvent (ethylene glycol), 1.1 kg pH adjuster (aqueous solution of citric acid), 1 kg preservative (sodium benzoate) and 60.9 kg deionized water.

[0088] According to the test, the pH value of the aqueous film-forming foam fire extinguishing agent is between 7.0 and 9.5.

[0089] Example 3

[0090] The method described in Example 1 is used for implementation, except that the aqueous film-forming foam fire extinguishing agent includes: 1 kg 1157 short-chain fluorocarbon surfactant, 28 kg hydrocarbon surfactant (compounded by sodium dodecylbenzene sulfonate, dodecyl dimethyl betaine and alkyl glycoside in a weight ratio of 1:3:3), 1 kg carboxyl-modified silicone surfactant, 10 kg antifreeze agent (urea), 0.5 kg corrosion inhibitor (sodium tripolyphosphate), 0.8 kg chelating agent (disodium ethylenediaminetetraacetic acid), 3 kg flame retardant (diammonium hydrogen phosphate), 2 kg cosolvent (ethylene glycol), 2 kg pH adjuster (aqueous citric acid solution), 1.5 kg preservative (sodium benzoate) and 50.2 kg deionized water.

[0091] According to the test, the pH value of the aqueous film-forming foam fire extinguishing agent is between 7.0 and 9.5.

[0092] Example 4

[0093] The method described in Example 1 is used for implementation, except that the aqueous film-forming foam fire extinguishing agent includes: 1.5 kg short-chain fluorocarbon surfactant (formed by compounding FS-50 and 1157 fluorocarbon surfactant in a weight ratio of 2:1), 15 kg hydrocarbon surfactant (formed by compounding sodium lauryl sulfate and cocamidopropyl betaine in a weight ratio of 1:2), 0.5 kg carboxyl-modified silicone surfactant, 6.6 kg antifreeze agent (urea), 0.3 kg corrosion inhibitor (sodium tripolyphosphate), 0.3 kg chelating agent (disodium ethylenediaminetetraacetic acid), 8 kg flame retardant (formed by compounding diammonium phosphate and ammonium polyphosphate in a weight ratio of 1:1), 2 kg cosolvent (butyl diethylene glycol), 0.8 kg pH regulator (aqueous solution of citric acid), 2 kg preservative (sodium benzoate) and 63 kg deionized water;

[0094] According to the test, the pH value of the aqueous film-forming foam fire extinguishing agent is between 7.0 and 9.5.

[0095] Example 5

[0096] The method described in Example 1 is used for implementation, except that the aqueous film-forming foam fire extinguishing agent includes: 1 kg FS-50 short-chain fluorocarbon surfactant, 18 kg hydrocarbon surfactant (compounded by dodecyl dimethyl betaine, cocamidopropyl betaine and alkyl glucoside in a weight ratio of 4:1:1), 2 kg carboxyl-modified silicone surfactant, 10 kg antifreeze agent (compounded by urea and ethylene glycol in a weight ratio of 4:1), 1.0 kg corrosion inhibitor (sodium tripolyphosphate), 0.7 kg chelating agent (disodium ethylenediaminetetraacetic acid), 4 kg flame retardant (compounded by diammonium phosphate and ammonium polyphosphate in a weight ratio of 1:1), 2 kg cosolvent (butyl diethylene glycol), 8 kg pH regulator (aqueous solution of citric acid), 2.5 kg preservative (sodium benzoate) and 50.8 kg deionized water;

[0097] According to the test, the pH value of the aqueous film-forming foam fire extinguishing agent is between 7.0 and 9.5.

[0098] Example 6

[0099] The method described in Example 1 is used for implementation, except that the aqueous film-forming foam fire extinguishing agent includes: 1 kg 1157 short-chain fluorocarbon surfactant, 20 kg hydrocarbon surfactant (compounded by sodium lauryl sulfate, cocamidopropyl betaine and alkyl glucoside in a weight ratio of 1:1:1), 1 kg carboxyl-modified silicone surfactant, 10 kg antifreeze agent (urea), 0.3 kg corrosion inhibitor (sodium tripolyphosphate), 0.2 kg chelating agent (disodium ethylenediaminetetraacetic acid), 1 kg flame retardant (diammonium hydrogen phosphate), 4 kg cosolvent (butyl diethylene glycol), 2.5 kg pH adjuster (aqueous solution of citric acid), 2.8 kg preservative (sodium benzoate) and 57.2 kg deionized water.

[0100] According to the test, the pH value of the aqueous film-forming foam fire extinguishing agent is between 7.0 and 9.5.

[0101] Example 7

[0102] The method described in Example 1 is used for implementation, except that the carboxyl-modified silicone surfactant is prepared according to the following process: hydroxy polyether-modified silicone siloxane and maleic anhydride are added to isopropanol in a weight ratio of 1:2, stirred evenly, and reacted at 60°C for 7 hours to obtain a reaction solution, wherein the ratio of the weight of isopropanol to the total weight of the hydroxy polyether-modified silicone siloxane and maleic anhydride is 30:100; the reaction solution is cooled to room temperature, and then the solution is transferred to a rotary evaporator, and the product is purified and recovered by reduced pressure distillation to obtain a carboxyl-modified silicone surfactant.

[0103] According to the test, the pH value of the aqueous film-forming foam fire extinguishing agent is between 7.0 and 9.5.

[0104] Example 8

[0105] This example is used to illustrate the aqueous film-forming foam fire extinguishing agent and its preparation method according to the present invention.

[0106] Aqueous film-forming foam fire extinguishing agent: 1.5kg short-chain fluorocarbon surfactant (compounded by FS-50 and 1157 fluorocarbon surfactant in a weight ratio of 1:1), 16kg hydrocarbon surfactant (compounded by sodium lauryl sulfate, cocamidopropyl betaine and alkyl glucoside in a weight ratio of 2:2:1), 0.8kg carboxyl-modified silicone surfactant, 3kg antifreeze agent (urea), 0.7kg corrosion inhibitor (sodium tripolyphosphate), 1kg chelating agent (disodium ethylenediaminetetraacetic acid), 2kg flame retardant (compounded by diammonium phosphate and ammonium polyphosphate in a weight ratio of 1:1), 1kg cosolvent (butyl diethylene glycol), 3kg pH adjuster (tartaric acid), 1kg preservative (sodium benzoate) and 70kg deionized water;

[0107] The carboxyl-modified organic silicone surfactant is prepared according to the following process: adding hydroxyl polyether-modified organic siloxane and maleic anhydride to isopropanol at a weight ratio of 1:0.5, stirring evenly, and reacting at 75° C. for 6 hours to obtain a reaction solution, wherein the weight ratio of isopropanol to the total weight of hydroxyl polyether-modified organic siloxane and maleic anhydride is 12:100; cooling the reaction solution to room temperature, then transferring the solution to a rotary evaporator, and purifying and recovering the product by reduced pressure distillation to obtain a carboxyl-modified organic silicone surfactant;

[0108] The aqueous film-forming foam fire extinguishing agent is prepared according to the method described in Example 1.

[0109] According to the test, the pH value of the aqueous film-forming foam fire extinguishing agent is between 7.0 and 9.5.

[0110] Example 9

[0111] The method described in Example 1 was followed, except that the FS-50 fluorocarbon surfactant was replaced with an equal amount of 1157 fluorocarbon surfactant.

[0112] Specifically, the aqueous film-forming foam fire extinguishing agent: 2.0kg short-chain fluorocarbon surfactant (1157 fluorocarbon surfactant), 22kg hydrocarbon surfactant (including sodium lauryl sulfate, cocamidopropyl betaine and alkyl glucoside in a weight ratio of 4:9:9), 1.5kg carboxyl modified silicone surfactant, 5kg antifreeze agent (urea), 0.3kg corrosion inhibitor (sodium tripolyphosphate), 0.2kg chelating agent (disodium ethylenediaminetetraacetic acid), 6kg flame retardant (including diammonium hydrogen phosphate and ammonium polyphosphate in a weight ratio of 1:1), 2kg co-solvent (diethylene glycol butyl ether), 1kg pH adjuster (aqueous solution of citric acid), 1kg preservative (sodium benzoate) and 59kg deionized water.

[0113] According to the test, the pH value of the aqueous film-forming foam fire extinguishing agent is between 7.0 and 9.5.

[0114] Example 10

[0115] The method described in Example 1 was followed, except that cocamidopropyl betaine was replaced with an equal amount of alkyl glucoside.

[0116] Specifically, the aqueous film-forming foam fire extinguishing agent: 2.0kg short-chain fluorocarbon surfactant (compounded by FS-50 and 1157 fluorocarbon surfactant in a weight ratio of 1:1), 22kg hydrocarbon surfactant (including sodium dodecyl sulfate and alkyl glycoside in a weight ratio of 4:18), 1.5kg carboxyl modified silicone surfactant, 5kg antifreeze agent (urea), 0.3kg corrosion inhibitor (sodium tripolyphosphate), 0.2kg chelating agent (disodium ethylenediaminetetraacetic acid), 6kg flame retardant (including diammonium hydrogen phosphate and ammonium polyphosphate in a weight ratio of 1:1), 2kg co-solvent (diethylene glycol butyl ether), 1kg pH adjuster (aqueous solution of citric acid), 1kg preservative (sodium benzoate) and 59kg deionized water.

[0117] According to the test, the pH value of the aqueous film-forming foam fire extinguishing agent is between 7.0 and 9.5.

[0118] Comparative Example 1

[0119] The method described in Example 1 was followed, except that all hydrocarbon surfactants were sodium dodecyl sulfate.

[0120] Specifically, the aqueous film-forming foam fire extinguishing agent: 2.0kg short-chain fluorocarbon surfactant (compounded by FS-50 and 1157 fluorocarbon surfactant in a weight ratio of 1:1), 22kg hydrocarbon surfactant (sodium dodecyl sulfate), 1.5kg carboxyl-modified silicone surfactant, 5kg antifreeze agent (urea), 0.3kg corrosion inhibitor (sodium tripolyphosphate), 0.2kg chelating agent (disodium ethylenediaminetetraacetic acid), 6kg flame retardant (compounded by diammonium phosphate and ammonium polyphosphate in a weight ratio of 1:1), 2kg co-solvent (butyl diethylene glycol), 1kg pH adjuster (aqueous solution of citric acid), 1kg preservative (sodium benzoate) and 59kg deionized water.

[0121] Comparative Example 2

[0122] The method described in Example 1 is followed, except that the hydroxyl-containing organosilicon surfactant is not modified, that is, when preparing the aqueous film-forming foam fire extinguishing agent, the carboxyl-modified organosilicon surfactant is replaced with a hydroxyl-containing organosilicon surfactant (hydroxy polyether-modified organosiloxane).

[0123] Test Example 1

[0124] The hydroxyl-containing organosilicon surfactant in Example 1 and the prepared carboxyl-modified organosilicon surfactant were subjected to Fourier transform infrared spectroscopy analysis. The results are as follows: Figure 1 As shown, Figure 1 In the above, a is a carboxyl-modified organic silicon surfactant, and b is a hydroxyl polyether-modified organic siloxane.

[0125] Depend on Figure 1 It can be seen that the carboxyl-modified silicone surfactant is at 3452 cm -1 The stretching vibration absorption peak of -OH appears at 2955cm -1 、2872cm -1 、1455cm -1 The stretching vibration absorption peaks of -CH2- and -CH3- appear at 1778cm -1 The stretching vibration absorption peak of -COOH appears at 1349 cm -1 The stretching vibration absorption peak of -CCO- appears at 1257cm -1 The stretching vibration absorption peak of -Si-C- appears at 1077cm- 1 The stretching vibration absorption peaks of -COC- and -Si-O-Si- appear at 1778cm. Comparing the spectra of the organosilicon surfactants before and after carboxyl modification, it is found that the infrared spectrum of the organosilicon surfactants after carboxyl modification has a peak at 1778cm -1There is obviously more -COOH stretching vibration peak at the position, which proves that the carboxyl group has been successfully introduced into the carboxyl-modified silicone surfactant, indicating that the carboxyl-modified silicone surfactant containing carboxyl functional groups has been successfully prepared.

[0126] Test Example 2

[0127] The fluorine-free foam fire extinguishing agents prepared in Examples 1-10 and Comparative Examples 1-2 were tested for surface activity, fire extinguishing performance and anti-burning performance. The test results are shown in Table 1 below.

[0128] Equipment used in the test: surface tension meter, foam generation system, foam collector, liquid analysis meter, balance, stopwatch, round steel oil pan (inner diameter: 2400mm, depth 200mm, oil pan area 4.52m 2 ), steel fire-resistant tank (inner diameter 300mm, depth 250mm).

[0129] Method for determining the surface activity of foam fire extinguishing agent solution: refer to GB 15308-2006 "Foam Fire Extinguishing Agent".

[0130] The specific steps of the fire extinguishing performance and anti-burning performance test are as follows: (1) First, prepare the fire extinguishing agent product and water in a ratio of 6:94 to form a foam solution, and fill it into the foam solution storage tank; (2) Apply a pressure of (0.7±0.03)MPa to the foam solution storage tank, and adjust the foam gun flow rate to make the foam flow rate 11.4L / min; (3) Place a circular oil pan on the ground and keep it horizontal, so that the oil pan is downwind of the foam gun, and add 90L of water to cover the bottom of the pan; (4) Place the foam gun horizontally and higher than the fuel surface (1±0.05 ) m, so that the center of the foam jet hits the central axis of the baffle and is (0.5±0.1) m higher than the fuel surface; (5) Add 144 L of fuel (#120 solvent oil for rubber industry) to the oil pan, and add 2 L of fuel to the anti-burn tank, and place it on the leeward side of the oil pan; (6) After adding the fuel, ignite the oil pan within 5 minutes, pre-burn for (60±5) seconds, start to supply foam, and record the fire extinguishing time; (7) After supplying foam for 300 seconds, wait for 300 seconds, place the anti-burn tank containing 2 L of fuel in the center of the oil pan and ignite it, and record the 25% anti-burn time.

[0131] Table 1

[0132]

[0133]

[0134] It can be seen from Table 1 that the surface tension of the aqueous film-forming foam fire extinguishing agent prepared in Examples 1-10 of the present invention is between 17.0 and 19.1 mN / m, and the fire extinguishing agent can extinguish 4.52 m 2The fire extinguishing time of the standard oil pan fire is between 80 and 130 seconds, and the 25% anti-burning time is not less than 700 seconds, indicating that the aqueous film-forming foam fire extinguishing agent provided by the present invention has excellent surface activity, fire extinguishing performance and anti-burning performance. The fire extinguishing time of the fire extinguishing agent prepared in Comparative Example 1 is 170 seconds, which is a long time; when the comparative example 2 extinguishes the standard oil pan fire, the edge fire is still burning 180 seconds after the foam is sprayed, and the fire cannot be successfully extinguished.

[0135] 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. An aqueous film-forming foam fire extinguishing agent, characterized in that: The aqueous film-forming foam fire extinguishing agent contains: a short-chain fluorocarbon surfactant, a hydrocarbon surfactant, a carboxyl-modified organic silicon surfactant, a cosolvent and a pH regulator; Wherein, the carboxyl-modified silicone surfactant is obtained by modifying a hydroxyl-containing silicone surfactant with maleic anhydride; The hydrocarbon surfactant is selected from at least two of anionic hydrocarbon surfactants, amphoteric hydrocarbon surfactants and nonionic hydrocarbon surfactants.

2. The aqueous film-forming foam fire extinguishing agent according to claim 1, characterized in that: In percentage, the aqueous film-forming foam fire extinguishing agent contains: 0.5-2wt% of short-chain fluorocarbon surfactant, 10-30wt% of hydrocarbon surfactant, 0.5-2wt% of carboxyl-modified organic silicon surfactant, 1-4wt% of cosolvent and 0.1-8wt% of pH regulator.

3. The aqueous film-forming foam fire extinguishing agent according to claim 1, characterized in that: The carboxyl-modified silicone surfactant is prepared according to the following process: The hydroxyl-containing organosilicon surfactant, maleic anhydride and organic solvent are mixed and stirred, reacted at 60-90° C. for 2-8 hours, and then cooled and purified.

4. The aqueous film-forming foam fire extinguishing agent according to claim 3, characterized in that: The weight ratio of the hydroxyl-containing organic silicon surfactant to maleic anhydride is 1:0.5-3.

5. The aqueous film-forming foam fire extinguishing agent according to claim 1 or 3, characterized in that: The hydroxyl-containing silicone surfactant is selected from one or more of hydroxyl polyether-modified silicone siloxane, terminal hydroxyl silicone block polyether, hydroxyl acrylic silicone and hydroxyl polyester silicone.

6. The aqueous film-forming foam fire extinguishing agent according to claim 3, characterized in that: The weight ratio of the organic solvent to the total weight of the hydroxyl-containing organosilicon surfactant and maleic anhydride is 10-40:100; Preferably, the organic solvent is selected from any one of isopropanol, n-propanol, propylene glycol, 1,3-butanediol and pentanediol.

7. The aqueous film-forming 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 amphoteric hydrocarbon surfactant is selected from one or more of cocamidopropyl betaine, dodecyl dimethyl betaine, N-dodecyl dimethyl betaine and 2-undecyl-N-acetoxy-N(2-hydroxyethyl)imidazoline; Preferably, the nonionic hydrocarbon surfactant is an alkyl glycoside.

8. The aqueous film-forming foam fire extinguishing agent according to claim 1, characterized in that: The short-chain fluorocarbon surfactant is selected from one or more of perfluoroalkyl amine oxides, perfluoroalkyl polyoxyethylene ethers, perfluoroalkyl ether betaines, and hexafluoropropylene oxide trimer quaternary ammonium salts.

9. The aqueous film-forming foam fire extinguishing agent according to claim 1, characterized in that: The co-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.

10. The aqueous film-forming foam fire extinguishing agent according to claim 1, characterized in that: The aqueous film-forming foam fire extinguishing agent also contains one or more of an antifreeze agent, a corrosion inhibitor, a chelating agent, a flame retardant and a preservative.

11. The aqueous film-forming foam fire extinguishing agent according to claim 10, characterized in that: The antifreeze agent is selected from one or more of urea, ethylene glycol and propanol; Preferably, the corrosion inhibitor is selected from one or more of sodium chromate, potassium chromate, sodium tripolyphosphate and sodium hexametaphosphate; Preferably, the chelating agent is disodium ethylenediaminetetraacetate; Preferably, the flame retardant is selected from one or more of potassium bicarbonate, sodium bicarbonate, diammonium hydrogen phosphate, ammonium polyphosphate, and diammonium dihydrogen phosphate; Preferably, the preservative is selected from one or more of sodium benzoate, potassium sorbate and methyl paraben.

12. The aqueous film-forming foam fire extinguishing agent according to claim 10, characterized in that: In percentage, the content of the antifreeze agent is 2-10wt%, the content of the corrosion inhibitor is 0.1-1wt%, the content of the chelating agent is 0.1-1wt%, the content of the flame retardant is 1-8wt%, and the content of the preservative is 0.1-3wt%.

13. A method for preparing the aqueous film-forming foam fire extinguishing agent according to any one of claims 1 to 12, characterized in that: The method comprises: mixing a hydrocarbon surfactant, a short-chain fluorocarbon surfactant, a carboxyl-modified organic silicon surfactant, a cosolvent, a pH regulator and water.

14. The method according to claim 13, characterized in that The method specifically includes: (1) Mixing a hydrocarbon surfactant with a portion of water under stirring, and then adding a short-chain fluorocarbon surfactant and a carboxyl-modified silicone surfactant to obtain a mixed solution A; (2) mixing and stirring the antifreeze agent, the corrosion inhibitor, the chelating agent, the flame retardant, the preservative, the cosolvent and the remaining water to obtain a mixed solution B; (3) The mixed solution A and the mixed solution B are mixed and stirred, and then a pH adjuster is added.

Images