FIRE EXTINGUISHING LIQUID CONTAINING A CARBOXYLATE SALT

Abstract

An aqueous fire sprinkler fluid containing a C4 or higher carboxylate salt for freezing point depression is described. The salts can be used in conjunction with glycols. The salts decrease flammability and provide a lower viscosity than fluids with higher glycol content, which is beneficial for fire sprinkler systems. These saline solutions are compatible with metal and CPVC piping and are therefore useful for fire sprinkler systems because they do not cause environmental stress cracking in CPVC components and are non-corrosive to metal parts.

Description

FIRE EXTINGUISHING FLUID CONTAINING A CARBOXYLATE SALT FIELD OF INVENTION The fluids in a fire sprinkler system must remain liquid at low temperatures, such as below 0°C and preferably below -40°C. They also need to protect the fire sprinkler system under long-term static conditions. As such, they must be compatible with and non-corrosive to the construction materials of a fire sprinkler system, as well as fulfill their primary function of suppressing or extinguishing fires. The fluids described herein include C4 or higher carboxylate salts (e.g., sodium or potassium) that act as an electrolyte to lower the freezing point of the water used in the solution, often in conjunction with a glycol. The selected salts also impart other desired properties described herein. BACKGROUND OF THE INVENTION Solutions for fire sprinkler fluids are currently subject to UL 2901, which sets out a series of performance standards that the fluid must pass to obtain certification, including freezing point, electrical conductivity, corrosion rate, and heat release, among others. Ethylene glycol aqueous solutions are commonly used for fire sprinkler fluids due to glycol's low corrosiveness and the low fire risk associated with it. Glycol is used to lower the freezing point of liquids. One problem with these solutions is their potential toxicity to the environment, food products, and animals, as well as the possible contamination of potable water systems to which the fire sprinkler system may be connected. For lower toxicity, some systems use or have been converted to propylene glycol as an alternative to ethylene glycol. Due to its higher carbon content, aqueous propylene glycol solutions must QLZfrnn / Lznz / E / Yii must be carefully balanced to avoid fire or explosion hazards associated with a fine mist of water containing organic carbon, exposed to a fire or ignition source. Similarly, given the aqueous nature of these fire sprinkler fluids, the possibility of electrocution arises if the fluids are sprayed around electrically carrying devices, from electrical sockets to electrical appliances and computers. Furthermore, fire sprinkler fluids must be compatible with the material of the pipe through which they are pumped. For example, the fluids must not be corrosive to iron pipes in particular, but also to non-ferrous metals, and must not degrade plastic pipes. With regard to plastic piping in particular, such sprinkler fluids can be used with chlorinated polyvinyl chloride (CPVC) pipe, such as Blaze Master®. High concentrations of propylene glycol, when exposed to CPVC pipe, can contribute to environmental stress cracking. To mitigate this concern, glycerin (also known as glycerol) has been used. One problem with glycerin, and to a lesser extent with any glycol, is the excessively high viscosity of the aqueous fluids at low temperatures. The low viscosity of the aqueous fluids at low temperatures is optimal for fire sprinklers. In summary, the ideal fire sprinkler fluid maintains good low-temperature fluidity, is non-toxic, non-flammable, non-corrosive to metals, compatible with plastics such as CPVC, and has low electrical conductivity. U.S. Patent 2,266,189 discloses antifreeze compositions using potassium acetate or potassium formate solutions, among others, as substitutes for water-glycol solutions as heat transfer fluids. It also describes the use of certain corrosion inhibitors and mentions the low viscosity of saline solutions compared to glycol or glycerol solutions. U.S. Patents 3,252,902; 4,756,839; 5,820,776; 5,945,025; and EP 0,376,963 B1 show carboxylate salts in fire extinguishing compositions, the latter four in combination with carbonate or bicarbonate. U.S. Patent 6,367,560 shows a potassium lactate solution in a cold-weather sprinkler system. United States Patent No.US Patent 6,059,966 describes a low-viscosity aqueous cooling brine based on inhibited alkali metal acetates and / or formates that has improved corrosion protection, wherein the cooling brines contain 0.2 to 5% by weight of alkali metal sulfites or pyrosulfites. US Patent 6,659,123 describes the maintenance of a cold-weather fire hydrant using potassium formate, preferably at least 10% by weight in water. US Patent 6,983,614, assigned to Lubrizol Corp., describes potassium formate heat transfer fluids. Japanese Patent Application JP2003135620 describes potassium formate at various concentrations in water as an antifreeze for fire sprinkler systems as a replacement for ethylene glycol.Small amounts of glycol are permitted to dissolve corrosion inhibitors, but the emphasis is on eliminating glycols altogether to reduce COD and BOD and the environmental burden. U.S. Publication No. 2014 / 0138105 A1 describes a fire extinguishing fluid containing a “low carbon number,” meaning a C1-C3 carboxylate salt. The publication focuses on potassium formate at levels above 10% by weight. It would be advisable to identify a fire extinguishing fluid that has good low-temperature flow and minimal tendency to corrode metal or degrade CPVC, with suppressed or inhibited combustibility, low electrical conductivity, and improved flowability. BRIEF DESCRIPTION OF THE INVENTION Current technology includes a fire extinguishing fluid that includes a C4 or higher carboxylate salt at low concentrations that can provide a fluid with good low-temperature flow and minimal tendency to corrode metal or degrade CPVC, with suppressed or inhibited combustibility, low electrical conductivity, and improved flowability. An aqueous liquid with a depressed freezing point for a fire sprinkler system that has water (such as demineralized water), a C2-C18 alkylene glycol, and a C4 or higher carboxylate. Suitable glycols for the fluid include ethylene glycol or propylene glycol. Similarly, suitable carboxylates for the fluid include disodium adipate or disodium succinate. The liquid may also include other components, such as a corrosion inhibitor, antioxidants, pH buffers, etc. The liquid can be used, for example, in a fire sprinkler system made of chlorinated polyvinyl chloride (“CPVC”) to prevent the sprinkler system from freezing. DETAILED DESCRIPTION OF THE INVENTION The aqueous fluid with a depressed freezing point for a fire sprinkler system may also be called fire sprinkler fluid or fire extinguishing fluid. A sprinkler system containing such fluid, which may also include piping or components made of CPVC, will also be described. The fluids are designed to be compatible with CPVC, have low corrosiveness to metals, particularly iron and steel, but also to non-ferrous metals. At the same time, the fluids do not freeze at low temperatures and have an acceptable low viscosity at low temperatures, such as below -10°C, and preferably remain liquid below -40°C. The antifreeze fluid described in this invention is suitable for use in a hydraulically calculated, water-based fire protection (sprinkler) system. In some embodiments, the fluid also has one or more of the following desirable properties: 1. Non-combustible when tested when exposed to fire in UL 2901 and on a full scale, based on UL 1626, room fire test for sprinkler ignition by use of sprinklers. QLZfrnn / Lznz / E / Yii 2. Freezing point protection to and below -40 °F (-40 °C) per NFPA 13.7.6.2 3. Good low temperature viscosity characteristics, i.e., low viscosity at low temperatures. 4. No flash point as determined by ASTM D 56 (D 92, D93...) 5. Inhibits the growth of microbiologically influenced corrosion (MIC) in metal-based piping systems. 6. Does not induce environmental stress cracking (ESC) in CPVC materials as determined by ASTM F 2331 7. It is not considered toxic or polluting to drinking water systems. 8. It has low electrical conductivity. The fire extinguishing fluids provided have a mixture of water, at least one C2 to C18 alkylene glycol and a salt of the C4 or higher carboxylic acid (also called a carboxylate). Preferably, the water component is demineralized water, which would reduce or eliminate the water's electrical conductivity. Demineralization can be carried out by any known method, such as distillation, deionization, reverse osmosis, or filtration. The water content in the fire extinguishing fluid can range from approximately 30 to approximately 80% by weight, based on the weight of the fire extinguishing fluid, or from approximately 35 to approximately 75% by weight, or even from approximately 35 to approximately 70% by weight, or even from 30% to 50% by weight, or from 35 to 45% by weight. A C2 to C1e alkylene glycol can be a diol or triol. The alkylene components can be linear, branched, cyclic, or aromatic. Suitable examples of C2 to C1e alkylene glycols include ethylene glycol, propylene glycol, butanediol, bisphenol A, resorcinol, glycerin, 1,3-propanediol, and similar compounds. Other examples may include sugar alcohols, sorbitol, mannitol, xylitol, erythritol, pentaerythritol, arabitol, inositol, and glycol ethers. In one embodiment, C2 to C18 alkylene glycol may be ethylene glycol. In another embodiment, C2 to C18 alkylene glycol may be propylene glycol. In some embodiments, C2 to C18 alkylene glycol may be glycerin. Some embodiments of C2 to C18 alkylene glycol may include a combination of glycols, such as propylene glycol and glycerin, or ethylene glycol and glycerin, or even propylene glycol and ethylene glycol. C2 to C18 alkylene glycol may be present in the fire extinguishing fluid at approximately 15 to 45% by weight based on the weight of the fire extinguishing fluid, or approximately 20 to approximately 42% by weight, or approximately 25 to approximately 40% by weight. Combinations of C2 alkylene glycol to C1e can also be used, for example, a two-part combination may be present at the above concentrations observed anywhere from 70 / 30 to 30 / 70% by weight of separation.Combinations of three or more C2 to C18 alkylene glycols can also be used. The fire extinguishing fluid also includes a C4 or higher carboxylate. The C4 or higher carboxylate may be a salt with, for example, L, K, Mg, Ca, Na and hydrates and combinations thereof. The C4 to C18 metal carboxylate can be a monovalent, divalent, or trivalent metal salt of a saturated C4 to C18 aliphatic carboxylate, an unsaturated C4 to C18 aliphatic carboxylate, a saturated C4 to C18 aliphatic carboxylate substituted with at least one OH group, or whose chain is interrupted by at least one oxygen atom (oxyacids), or a cyclic or bicyclic carboxylate. In some embodiments, the monovalent, divalent, or trivalent metal carboxylate can be a C4 to C18 metal carboxylate, a C4 to C16 metal carboxylate, or even a C4 to C12 metal carboxylate. The carboxylate in a C4 to C18 metal carboxylate can be a monocarboxylate. Monocarboxylates can include, for example, metal salts of lauric acid or stearic acid, such as sodium laurate or sodium stearate. The carboxylate in a C4 to C18 metal carboxylate can also be a dicarboxylate. Examples of C4 to C18 metal carboxylates include disodium sebacate, disodium dodecanedioate, or disodium suberate, and combinations thereof. Other examples of C4 to C18 metal dicarboxylates that can be used include disodium adipate, disodium succinate, disodium azelate, and disodium undecanedioate. The carboxylate in a C4 to C18 metal carboxylate can also be a tricarboxylate, such as, for example, QLZfrnn / Lznz / E / Yii metal salts of citric acid, such as trisodium citrate or tripotassium citrate, or aconitic acid, such as trisodium or tripotassium aconitic acid. In some forms, the liquid may include a combination of two or more of the monocarboxylates, dicarboxylates, and tricarboxylates. Although C4 or higher carboxylates are preferred, they can be used in conjunction with salts of low-carbon carboxylic acids (e.g., C1-C3). Examples of low-carbon carboxylic acids include formic acid, acetic acid, propionic acid, glycolic acid, lactic acid, and the like. Potassium formate and sodium formate are examples of low-carbon metal carboxylates that can be used in conjunction with C4 to C1 metal carboxylates. Salts of C4 or higher carboxylic acids may be present in the mixture in sufficient quantity to achieve the desired freezing point required for the fire-extinguishing environment. This is generally achieved by determining the coldest temperature to which the liquid will be exposed and then preparing a liquid that will remain thawed at a temperature at least 5°C colder than the anticipated temperature. In some cases, the salt of a C4 or higher carboxylic acid may be present in the fire extinguishing fluid from approximately 0.01 to approximately 15% by weight based on the weight of the fire extinguishing fluid, or from approximately 0.05 to approximately 12% by weight, or even from approximately 0.1 to approximately 10% by weight. In some cases, the salt of a C4 or higher carboxylic acid may be present in the fire extinguishing fluid in amounts greater than approximately 2 to approximately 15% by weight based on the weight of the fire extinguishing fluid, or from approximately 2.1 or 2.2 to approximately 14% by weight, or even from approximately 2.5 to approximately 12% by weight, and even from 2.75 or 3 to 10% by weight. In some cases the salt of the C4 or higher carboxylic acid may be present in an amount of approximately 3 to approximately 9% by weight or 3 to 8% by weight. QLZfrnn / Lznz / E / Yii The fire extinguishing fluid may also optionally include an antioxidant. Any antioxidant soluble in water / glycol systems may be used. Examples include butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA), THBP, TBHQ, 4-hydroxyphenylpropionic acid, propyl gallate, 3,3-thiodipropionic acid, N-phenyl-alpha-naphthylamine (PANA), octylated / butylated diphenylamine, high molecular weight phenolic antioxidants, hindered bisphenol antioxidant, di-alpha-tocopherol, tertiary dibutylphenol, and similar compounds, and combinations thereof. Antioxidants may be present in the composition at concentrations of 0.01% to 6.0%, or from 0.02%, 0.03%, 0.05%, 0.1% to 6%, 4%, 2%, 1%, or even 0.5%. The fluid can be buffered with various buffers to control pH variation should the spray fluid become further diluted or contaminated with an acid or base. The buffer may comprise various glycines and / or carbonates, borates, and alkali metal phosphates. These include combinations such as sodium phosphate, disodium phosphate, and trisodium phosphate, various borates, glycine, and combinations of sodium bicarbonate or potassium bicarbonate, sodium carbonate, or potassium carbonate. Counterions, such as sodium, potassium, lithium, calcium, and magnesium, are not critical for buffering and, due to the presence of excess potassium, can be exchanged with other cations. Selected corrosion inhibitors that exhibit good solubility in high-salt aqueous solutions are used in liquids based on C4 or higher carboxylate salts. These corrosion inhibitors can be present in concentrations up to 4 percent by weight and conveniently above 0.001 percent by weight or from approximately 0.1 percent by weight up to 2 percent by weight based on the weight of the liquid.Corrosion inhibitors include triazole inhibitors such as benzotriazole (preferred in combination), substituted benzotriazoles, triazole tolyl and its derivatives (e.g., Irgamet® 42), benzimidazole, a diazole such as dimercaptothiadiazole (preferred in combination); water-soluble arylsulfonates, citric acid, sulfamic acid, inorganic nitrites, and mixtures of C2-C8 monocarboxylic acid or alkali, ammonium, or amino salts of said acid, a C2-C8 dicarboxylic acid or alkali, ammonium, or amino salts of said acid (Irgacor® L 190). Vapor-phase corrosion inhibitors can also be added to the liquid and would reduce corrosion on surfaces that are not always in contact with the liquid. A preferred vapor-phase corrosion inhibitor would be the tertiary amine, FUN, where R contains 1 to 4 carbon atoms.Vapor-phase corrosion inhibitors are generally suitable at concentrations up to 0.3 percent by weight of the liquid. Borates, such as borax (optionally used as buffers), can also function as corrosion inhibitors. Higher carboxylic acids, such as 2-ethylhexanoic acid, or dicarboxylic acids, such as sebacic acid or their salts, can act as corrosion inhibitors. Even some low-carbon carboxylic acids, such as lactic or propionic acid, or low-carbon diacids, such as tartaric or citric acid, or their salts, can act as corrosion inhibitors. Biocides are also convenient components in fire sprinkler fluid. Biocides prevent the growth of various plants and animals that may be introduced from the water supply or that have been growing in the fluid. Ideally, the biocide is present at a concentration of less than 0.5 percent by weight, and more conveniently, less than 0.3 percent by weight. Preferred biocides are various copper salts that can effectively control most plant and animal growth at concentrations of less than 0.025 percent by weight, and more conveniently, less than 0.005 percent by weight, based on the weight of the fluid. The copper cation appears to be primarily associated with biocidal activity. With these copper salts, the actual copper concentration is less than 100 ppm, and more conveniently, less than 25 ppm. Suitable copper salts include copper acetate, copper sulfate, and copper citrate.Copper salts can also help prevent certain types of corrosion. Glutaraldehyde can also be added to the fluid as a biocide. Borates also inhibit bacterial growth, etc. It is advantageous for both the corrosion inhibitors and the biocide to be soluble at levels higher than those required for many applications, so that the entire fire sprinkler fluid can be prepared as a concentrate. This allows for the application of effective concentrations of the corrosion inhibitor and / or biocide after dilution with water at the point of use to form a fire sprinkler fluid. Metal ion scavengers (chelating agents) such as ethylenediaminetetraacetic acid or its salt (EDTA) may also be included. Convenient concentrations of chelating agents are up to 2 or 6 percent by weight, and more conveniently from approximately 0.2 to approximately 6 percent by weight based on the weight of the liquid. While fire extinguishing fluid is compatible with CPVC components, such as CPVC pipes and fittings, its use is not limited to them. In fact, fire extinguishing fluid can be used in any fire suppression piping system, including systems containing metallic components such as iron, copper, steel (including stainless and galvanized steel), brass, and combinations thereof.The liquid can also be used in other types of plastic piping systems, including, for example, polypropylene reinforced (PPR) systems, polypropylene random copolymer systems, high-temperature polyethylene (PE-RT) systems, cross-linked polyethylene (PEX) systems, systems with nitrite rubbers such as nitrile butadiene rubber (NBR) and similar materials, systems containing EPDM, systems with elastomeric materials, styrene butadiene rubber (SBR), and combinations thereof. The liquid can also be used in systems containing both metal and plastic components. Several combinations of water-based fire extinguishing fluid formulations were prepared and their performance was tested according to the performance standards in UL 2901 for freezing point (ASTM D1177), electrical conductivity (ASTM D1125), corrosion index (NFPA 18A), and heat release (section 17.5.1 of UL2901). The tested formulations are set out below, where “PG” is polyethylene glycol, “Gly” is glycerin, “EG” is ethylene glycol, “Di Adipate” is disodium adipate, “Di Succ” is disodium succinate and “K+ Formate” is potassium formate. QLZfrnn / Lznz / E / Yii Comparative formulations using only one alkylene glycol. Sample PG Glv EG Freezing Point βH Conductivity (% by weight) CC) (millisiemens / cm ± 0.5 mS / cm) 1 31 -13.7 7 1.1 2 44 -26.9 8 1.1 3 49 -31.7 8 1.1 4 54 -44.3 7 0.9 5 31 -11.9 7 3.2 6 44 -18.7 7 2.2 7 49 -22.8 7 2 8 54 -27.4 7 1.7 9 44 -28.2 7 5.8 10 51 -34 7 5.5 11 30 30 -43.6 7 0.9 12 22 22 -23.1 6 1.5 13 26 26 -28.9 5 1.5 QLZfrnn / Lznz / E / Yii Comparative formulations that use only one carboxylate. Sample Di Adi Dato Di Suco K+ Formate Freezing Point Conductivity (% by weight) (°C) (millisiemens / cm ± 0.5 mS / cm) 14 3 -1.7 8 19 15 6 -5 8 32.4 16 12 -6.2 7 50.4 17 3 -3.1 7 23.7 18 6 -4.3 7 40.2 19 12 -6.5 7 62.7 20 3 -3.5 7 34.7 21 6 -4.8 7 63.7 22 12 -7.1 7 114.5 23 4 4 4 -5 8 73.9 Formulations that use a succinate-based product Sample PG Glv Di Succ Freezing Point eh Conductivity (% by weight) (Ό) (millisiemens / cm ± 0.5 mS / cm) 24 22 22 3 -27.9 7.5 6 25 22 22 6 -33.3 7.6 9.6 26 24.5 24.5 6 -41.5 8.7 7.5 27 25.5 25.5 6 -38.6 7.7 6.6 28 25.5 25.5 12 -47.1 7.4 9.5 Formulations that use an adipate-based product. Sample PG Glv EG Di Adi Data Convection Point pH Conductivity (% by weight) CC) (millisiemens / cm ± 0.5 mS / cm) 29 31 1.9 -16.2 7.9 5.1 30 31 1.9 -12.3 7.6 6.2 31 31 3 -10.5 9 8.9 32 31 6 -13.8 7.4 14.9 33 22 22 3 -26.9 8 6.4 34 25.5 25.5 6 -31 7.2 8.8 35 22 22 3 -29 7.9 4.9 36 22 22 6 -27.5 7.3 8.6 37 25 25 6 -43.3 7.5 5.7 38 25.5 25.5 6 -42.4 7.2 6.3 39 25.5 25.5 12 -45.2 7.1 7.1 40 27 27 6 -49 41 25.5 25.5 9 -48.8 7.2 6.7 42 24.5 24.5 9 -44.8 7.2 7.4 Formulations that use a formate-based product. Sample PG Glv K+ Formate Contamination Point pH Conductivity (% by weight) (“C) (millisiemens / cm ± 0.5 mS / cm) 43 22 22 3 -25.8 7 10.3 44 22 22 6 -31.3 7.2 18.4 45 25.5 25.5 6 -39.3 7.3 13.3 46 25.5 25.5 12 -47.3 7.6 20.8 A series of microscale combustion calorimeter (“MCC”) tests were also performed in accordance with ASTM D7309-13 on the formulations shown in the table below. The freezing point of the samples was also tested in accordance with ASTM D6660. q Lz^nn / Lznz / E / YiAi Samples 47 48 49 50 51 52 53 54 55 Ingredients (% by weight) Water 34 34 34 53 37 53 37 53 37 Propylene glycol 54 22 25.5 22 25.5 22 25.5 Glycerin 54 54 22 25.5 22 25.5 22 25.5 Disodium diethylamide 12 3 12 Disodium succinate 3 12 Potassium formate 12 12 3 12 Each of the samples from 47 to 55 was analyzed three times. The average of the three MCC test results for each sample is provided below, along with the freezing point. Sample D6660 Freezing Point (°C) Heat Release Capacity (J / gK) Maximum Heat Release Temperature (°C) Maximum Specific Heat Release Rate (W / g) Pyrolysis Residue (g / g) Specific Heat of Combustion (J / g) 47 -56.0 228 181 225 0.1704 13.9 48 -48.3 161 292 161 0.0756 10.6 49 -51.6 95 261 97 0.1327 9.7 50 -25.1 99 169 95 0.0092 8.7 51 -52.0 91 207 90 0.0709 11.7 52 -25.6 117 176 114 0.0364 8.5 53 -50.9 109 183 104 0.1072 10.6 54 -25.4 99 179 94 0.0227 8.5 55 -53.4 97 213 94 0.0852 11.2 Each of the samples from 47 to 55, along with several commercially available antifreeze solutions, was also subjected to corrosion testing in accordance with ASTM G71, with the following parameters. Each test used 250 ml of solution in a 600 ml beaker, covered with parafilm to prevent evaporation, with the metal coupons immersed 1 inch in the solution using the following combinations of metal coupons: 1008 carbon steel / semi-hard brass and 1008 carbon steel / copper. The coupon dimensions were as follows: 1008 carbon steel 6” x 1” x 0.032”, semi-hard brass 56” x 1.5” x 0.125”, and copper 6” x 2” x 0.032”. The metal coupons were separated using a T-shaped plastic holder, secured by a plastic clamp and electrically coupled through the test solution. The test was conducted for 7 days with voltage readings recorded twice daily.The final values ​​reported were the voltage in millivolts after 7 days. The test results can be seen in the following table. QLZfrnn / Lznz / E / Yii Brass / Steel Copper / Steel Sample Final Voltage (mV) Final Voltage (mV) 47 145.3 101.1 48 193.8 66.4 49 113.0 89.3 50 47.3 86.7 51 140.5 75.9 52 115 107.8 53 43.8 126.1 54 54.6 83.8 55 159.3 77.0 Water 684 708 Noburst™ 100* 162.3 106.0 Firefighter™ gl48** 159.0 121.4 Firefighter™ pg38*** 106.7 110.8 * Commercially available propylene glycol-based antifreeze from Noble Company ** Commercially available 48% glycerin antifreeze solution from Noble Company *** Commercially available 38% propylene glycol antifreeze solution from Noble Company Each of the documents mentioned above is incorporated herein by reference. Except in the examples, or where explicitly stated otherwise, all numerical quantities in this description specifying amounts of materials, reaction conditions, molecular weights, number of carbon atoms, and the like, are to be understood as modified by the word "approximately." Unless otherwise stated, each chemical substance or composition referenced herein is to be interpreted as a commercial-grade material that may contain the isomers, by-products, derivatives, and other such materials normally understood to be present in commercial grade. It is to be understood that the upper and lower limits of quantity, range, and ratio stated herein may be combined independently.While intervals are given for most elements of the invention independently of the intervals for other elements, it is anticipated that in the most preferred embodiments of the invention, the elements of the invention will be combined with the various desired or preferred intervals for each element of the invention in several combinations. As used herein, the expression "essentially" permits the inclusion of substances that do not materially affect the basic and novel features of the composition under consideration. An aqueous liquid with a depressed freezing point for a fire sprinkler system comprising: a) water, b) at least one C2C18 alkylene glycol (15-65;20-60;25-55), and c) at least one C4 or higher carboxylate (0.01-15;0.1-12;1-10). The aqueous liquid with a depressed freezing point for a fire sprinkler system of any of the above sentences where water is present at approximately 30 to approximately 80% by weight. The aqueous liquid with a depressed freezing point for a fire sprinkler system of any of the above sentences where water is present from approximately 35 to approximately 75% by weight. QLZfrnn / Lznz / E / Yii The aqueous liquid with a depressed freezing point for a fire sprinkler system of any of the above sentences where water is present at approximately 30 to approximately 50% by weight. The aqueous liquid with a depressed freezing point for a fire sprinkler system of any of the above sentences where water is present from approximately 35 to approximately 45% by weight. The aqueous liquid with a depressed freezing point for a fire sprinkler system of any of the above sentences wherein at least one C2-C18 alkylene glycol is present from approximately 15 to approximately 60% by weight. The aqueous liquid with a depressed freezing point for a fire sprinkler system of any of the above sentences wherein at least one C2-C18 alkylene glycol is present from approximately 15 to approximately 45% by weight. The aqueous liquid with a depressed freezing point for a fire sprinkler system of any of the above sentences wherein at least one C2-C18 alkylene glycol is present from approximately 20 to approximately 42% by weight. The aqueous liquid with a depressed freezing point for a fire sprinkler system of any of the above sentences wherein at least one C2-C18 alkylene glycol is present from approximately 25 to approximately 40% by weight. The aqueous liquid with a depressed freezing point for a fire sprinkler system of any of the above sentences wherein at least one C4 or higher carboxylate is present from approximately 0.01 to approximately 15% by weight. The aqueous liquid with a depressed freezing point for a fire sprinkler system of any of the above sentences wherein at least one C4 or higher carboxylate is present from approximately 0.05 to approximately 12% by weight. QLZfrnn / Lznz / E / Yii The aqueous liquid with a depressed freezing point for a fire sprinkler system of any of the above sentences wherein at least one C4 or higher carboxylate is present from approximately 0.1 to approximately 10% by weight. The aqueous liquid with a depressed freezing point for a fire sprinkler system of any of the above sentences wherein at least one C4 or higher carboxylate is present from approximately 2 to approximately 15% by weight. The aqueous liquid with a depressed freezing point for a fire sprinkler system of any of the above sentences wherein at least one C4 or higher carboxylate is present from approximately 2.1 to approximately 15% by weight. The aqueous liquid with a depressed freezing point for a fire sprinkler system of any of the above sentences wherein at least one carboxylate O4 or greater is present from approximately 2.1 to approximately 14% by weight. The aqueous liquid with a depressed freezing point for a fire sprinkler system of any of the above sentences wherein at least one C4 or higher carboxylate is present from approximately 2.2 to approximately 14% by weight. The aqueous liquid with a depressed freezing point for a fire sprinkler system of any of the above sentences wherein at least one C4 or higher carboxylate is present from approximately 2.5 to approximately 12% by weight. The aqueous liquid with a depressed freezing point for a fire sprinkler system of any of the above sentences wherein at least one C4 or higher carboxylate is present from approximately 2.75 to approximately 10% by weight. The aqueous liquid with a depressed freezing point for a fire sprinkler system of any of the preceding sentences where at least one QLZfrnn / Lznz / E / Yii C4 or higher carboxylate is present from approximately 3 to approximately 10% by weight. The aqueous liquid with a depressed freezing point for a fire sprinkler system of any of the above sentences wherein at least one C4 or higher carboxylate is present from approximately 3 to approximately 9% by weight. The aqueous liquid with a depressed freezing point for a fire sprinkler system of any of the above sentences wherein at least one C4 or higher carboxylate is present from approximately 3 to approximately 8% by weight. The liquid in any of the above sentences, where the water is demineralized water. The liquid of any of the above sentences, wherein the C2 to C1 alkylene glycol comprises a diol. The liquid of any of the above sentences, wherein the C2 to C1 alkylene glycol comprises a triol. The liquid of any of the above sentences, wherein the C2 to C1 alkylene glycol comprises a linear alkylene component. The liquid of any of the above sentences, wherein the C2 to C1 alkylene glycol comprises a branched alkylene component. The liquid of any of the above sentences, wherein the C2 to C1 alkylene glycol comprises a cyclic alkylene component. The liquid of any of the above sentences, wherein the C2 to C1 alkylene glycol comprises an aromatic alkylene component. The liquid of any of the above sentences, wherein the C2 to C1 alkylene glycol comprises ethylene glycol. The liquid of any of the above sentences, wherein the C2 to C1 alkylene glycol comprises propylene glycol. The liquid of any of the above sentences, wherein the C2 to C1 alkylene glycol comprises butanediol. q 1 znnn / i zoz / e / yl The liquid in any prayer contains bisphenol. The liquid in any prayer contains resorcinol. The liquid in any prayer comprises glycerin. The liquid in any sentence comprises 1,3-propanediol. The liquid in any prayer comprises a sugar alcohol. The liquid in any sentence comprises sorbitol. The liquid in any prayer contains mannitol. The liquid in any sentence comprises xylitol. The liquid in any prayer contains erythritol. The liquid in any prayer comprises pentaerythritol. The liquid in any prayer contains arabitol. The liquid in any prayer contains inositol. The liquid in any sentence comprises a glycol ether. The liquid of any sentence comprises a combination of 70 / 30 above, wherein the alkylene glycol ... C2 to C18 C2 to C18 C2 to Cíe C2 to Gis C2 to C18 C2 to Cíe C2 to C18 C2 to Gis C2 to Cíe C2 to C18 C2 to Cíe C2 to C18 C2 to C18 C2 to Cíe The liquid of any of the above sentences, wherein the C2 to C1 alkylene glycol comprises a 50 / 50 combination of glycols. q 1 znnn / i zoz / e / yl The liquid of any of the above sentences, wherein the C2 to C1 alkylene glycol comprises a 60 / 40 combination of glycols. The liquid of any of the above sentences, wherein the C2 to C1 alkylene glycol comprises a 70 / 30 combination of glycols. The liquid of any of the above sentences, wherein the C2 to C1 alkylene glycol comprises propylene glycol and glycerin. The liquid of any of the above sentences, wherein the C2 to C1 alkylene glycol comprises ethylene glycol and glycerin. The liquid of any of the above sentences, wherein the C2 to C1 alkylene glycol comprises propylene glycol and ethylene glycol. QLZfrnn / Lznz / E / Yii The liquid in any sentence comprises a salt of L!. The liquid in any sentence comprises a K salt. The liquid in any prayer comprises a Mg salt. The liquid in any prayer comprises a Ca salt. The liquid in any sentence comprises a sodium salt. The liquid in any sentence comprises a hydrate salt. The liquid in any sentence comprises a monovalent salt. The liquid in any sentence comprises a divalent salt. The liquid in any sentence comprises a trivalent salt. The liquid of any previous sentence, in which C4 or higher C4 carboxylate comprises a saturated aliphatic C4 carboxylate. The liquid of any of the above sentences, wherein the C4 or higher carboxylate comprises an unsaturated C4 aliphatic carboxylate. The liquid of any of the above sentences, wherein the C4 or higher carboxylate comprises a saturated C4 aliphatic carboxylate substituted with at least one OH group. The liquid of any of the above sentences, wherein the C4 or higher carboxylate comprises a saturated C4 aliphatic carboxylate having its main chain interrupted by at least one oxygen atom (i.e., the C4 or higher carboxylate comprises an oxyacid). The liquid of any of the above sentences, wherein the C4 or higher carboxylate comprises a cyclic carboxylate. The liquid of any of the above sentences, wherein the C4 or higher carboxylate comprises a bicyclic carboxylate. The liquid of any of the above sentences, wherein the C4 or higher carboxylate comprises a metal carboxylate O4 to Cíe. The liquid of any of the preceding sentences, wherein the C4 or higher carboxylate comprises a C4 to C1 metal carboxylate. The liquid of any of the above sentences, wherein the C4 or higher carboxylate comprises a Ce to C12 metal carboxylate. The liquid of any of the above sentences, wherein the C4 or higher carboxylate comprises a monocarboxylate. The liquid of any of the above sentences, wherein the C4 or higher carboxylate comprises a metal salt of lauric acid. The liquid of any of the above sentences, wherein the C4 or higher carboxylate comprises a metal salt of stearic acid. The liquid of any of the above sentences, wherein the C4 or higher carboxylate comprises a dicarboxylate. The liquid of any of the above sentences, wherein the C4 or higher carboxylate comprises a disodium sebacate. The liquid of any of the above sentences, wherein the carboxylate O or higher comprises a disodium dodecanediate. The liquid in any of the above sentences comprises a disodium suberate. The liquid in any of the above sentences comprises a disodium adipate. The liquid in any of the above sentences comprises disodium succinate. The liquid in any of the above sentences comprises a disodium azelate. The liquid in any of the above sentences comprises disodium undecanediate. The liquid in any of the above sentences comprises a tricarboxylate. The liquid in any of the above sentences comprises a metal salt of citric acid. in in in in in in in The liquid in any of the above sentences comprises a trisodium citrate. The liquid in any of the above sentences, where where where where where where where where where where where comprises a tripotassium citrate. The liquid of any of the preceding sentences, where it comprises a metal salt of aconitic acid. carboxylate carboxylate carboxylate carboxylate carboxylate carboxylate carboxylate carboxylate carboxylate carboxylate C4 C4 C4 C4 C4 C4 C4 major major major major major major major major major major major major major The liquid of any of the above sentences, which further comprises a salt of the low carbon number carboxylic acid (e.g., C1-C3). The liquid of any metal prayer of formic acid. The liquid of any metal prayer of acetic acid. The liquid of any metal propionic acid prayer. The liquid of any metal prayer of glycolic acid. previous, previous, previous, previous, which which which which also also also also includes includes includes includes a a a a salt salt salt salt of of of of of q 1 ζπηη / ι znz / e / Yl· The liquid of any of the above sentences, which further comprises a metal salt of lactic acid. The liquid of any of the above sentences, wherein the liquid further comprises a corrosion inhibitor. The liquid of any of the above sentences, wherein the liquid further comprises an antioxidant. A fire sprinkler system containing the liquid from any of the above sentences. A fire sprinkler system of any of the above sentences that contains CPVC components. A method for preventing a fire sprinkler system from freezing, comprising placing in the fire sprinkler system an aqueous liquid with a depressed freezing point as claimed in any of the preceding sentences.

Claims

1. An aqueous liquid with a depressed freezing point for a fire sprinkler system characterized in that it comprises: a. from approximately 30 to approximately 80% by weight of water, b. from approximately 15 to approximately 65% ​​by weight of a combination of at least two C2-C18 alkylene glycols, and c. from approximately 3 to approximately 9% by weight of at least one of sebacate, adipate, succinate, citrate and mixtures thereof.

2. The liquid according to claim 1, wherein the water is demineralized water.

3. The liquid according to claim 1 or 2, wherein the C2 to C18 alkylene glycol comprises ethylene glycol, propylene glycol, glycerin, or mixtures thereof.

4. The liquid according to claim 1 or 2 or 3, wherein the liquid further comprises a corrosion inhibitor.

5. The liquid according to claim 1 or 2 or 3 or 4, wherein the liquid further comprises an antioxidant.

6. A fire sprinkler system containing the liquid according to any of claims 1 to 5.

7. A fire sprinkler system according to claim 6 containing CPVC components.

8. A method for preventing a fire sprinkler system from freezing, comprising placing in the fire sprinkler system an aqueous liquid with a depressed freezing point as claimed in any one of claims 1 to 5.