RU2457235C1 - Concentrate for liquid coolant and use thereof as agent for reducing chilling point of liquid coolant - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: concentrate contains the following in wt %: C₁-C₃ monoatomic alcohol 52.5-80.0, diatomic alcohol from the family of glycols as a water-soluble depressant 8.0-20.0, glycerine 8.0-27.0 and a packet of inhibiting additives - not more than 5.0. Said concentrate ensures efficient reduction of the temperature of liquid coolants when used in ratio to the liquid coolant of 1:6-16.

EFFECT: improved temperature characteristics while preserving all the other parameters of liquid coolants by reducing the chilling point.

7 cl, 2 tbl, 3 ex

Description

The invention relates to the field of chemical technology, in particular to compositions for reducing the crystallization temperature of coolants, and is intended to be added to coolants (coolants) during operation of internal combustion engines and as a coolant in heat exchangers.

It is known that the main operational properties of coolants (the equivalent term antifreeze) are:

- high thermal conductivity;

- low pour point;

- high boiling point;

- optimal chemical stability;

- the absence of corrosive effects on the structural materials of the radiator and engine;

- protection of parts of the cooling system from cavitation destruction;

- inertness to rubber products;

- lack of foaming at elevated temperatures.

To improve these operational properties of the coolant, a lot of tools are known. These are various types of coolant compositions, concentrates, inhibitors: RU 2046815 C1, C09K 5/00, 1995; RU 2050397 C1, C09K 5/00, 1995; RU 2095388 C1, C09K 5/00, 1997; RU 2170752 C2, C09K 5/20, C23F 11/12, 2001; RU 2196797 C1, C09K 5/00, 2001; RU 2241784 C1, C23F 11/08, 2004; RU 2302479 C1, C09K 5/20, C23F 11/10, 2007; RU 2362792 C1, C09K 5/00, C23F 11/12, 2009; RU 2393271 C1, C23F 11/14, 2010; RU 2263131 C, C09K 5/20, 2005; RU 2315797 C2, C09K 5/10, 2008, etc.

The compositions of the coolant, concentrates and antifreezes are characterized by the presence of a depressant - the basis is alcohols (polyols) or a mixture of alcohols and a package of inhibitory additives. Of the alcohols used, as a rule, dihydric alcohols: monoethylene glycol, propylene glycol. The additive package is more diverse. In this case, the concentrates are diluted with water to obtain the coolant of the required composition with the required operational characteristics.

The applicant has not identified information that would concern concentrates added to operational coolants to improve temperature characteristics, for example, when the ambient temperature changes, when changing climatic zones.

The problem of improving temperature characteristics exists both in the operation of internal combustion engines, and in the operation of the coolant in heat exchangers. Therefore, the solution of the existing problem is an urgent task.

Known corrosion inhibitor for low-freezing coolants, which contains, wt.%: 3-4 sebacic acid, 8-9 adipic acid, 6.5-7.5 sodium hydroxide, 3.5-4.0 benzoic acid, 30-40 water, 0.25-0.50 benzotriazole, 1-2 sodium bicarbonate, the rest is ethylene glycol (RU 2302479 C1, C23F 11/10, C09K 5/20, 07/10/2007). Samples of coolants are prepared from the composition of the corrosion inhibitor by diluting it with an aqueous solution of ethylene glycol (54-56 vol.%) In a ratio of 1: 9.

Known corrosion inhibitor for low freezing coolants, which contains, wt.%: 5.5-6.5 sebacic acid, 3.0-4.0 adipic acid, 6.0-7.0 sodium hydroxide, 2.0-3 , 0 benzoic acid, 35-40 water, 0.25-0.50 benzotriazole, 2.5-3.5 succinic acid, 0.02-0.04 N-phenyl-2-naphthylamine, the rest is ethylene glycol (RU 2393271 C1, C23F 11/14, 06/27/2010). Samples of coolants are prepared from the composition of the corrosion inhibitor by diluting it with an aqueous solution of ethylene glycol (54-56 vol.%) In a ratio of 1: 9.

The use of prepared coolants based on known concentrates makes it possible to increase the corrosion resistance of all structural materials of the internal combustion engine cooling system and to prevent the risk of pitting corrosion on the surface of steel and cast iron, however, the patents do not contain information on the possibility of lowering the temperature of the onset of crystallization of the coolant.

A known composition of a fuel cell coolant concentrate containing a water-soluble freezing point depressant based on liquid alcohol and C ₅ -C ₁₈ carboxylic acid or a mixture of C ₅ -C ₁₈ carboxylic acids or their salts in an amount of from 0.1 to 10 wt.% (RU 2315797 C2, C09K 5/10, H01M 8/04, 01/27/2008).

As an example, sebacic acid is used as a carboxylic acid; monoethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, methyl, ethyl, propyl and butyl ethers of ethylene glycol, diethylene glycol, propylene glycol and dipropylene glycol, mainly monoethylene glycol, are used as a depressant; sodium hydroxide from 0.1 to 5.0 wt.% based on the total weight of the composition of the concentrate. A package of inhibitory additives, for example triazole and / or thiazole, or other corrosion inhibitors known in the art to a concentration of 1.0% by weight based on the total weight of the concentrate composition, is also added to the composition.

Further, to obtain the coolant, the known composition is diluted with water, adding 10-90 vol.%, Preferably 30-70% of water.

Thus, the known concentrate is diluted with water and then used as coolant.

The patent does not contain information on the use of a concentrate composition to improve temperature characteristics by adding concentrate to an operating coolant.

The technical result of the invention is to improve the temperature characteristics of the operating coolants by reducing the crystallization temperature, while maintaining high values of other coolant parameters.

The technical result is achieved in that the concentrate for improving the temperature characteristics of the coolant contains a monohydric alcohol from the C ₁ -C ₃ series, a dihydric alcohol from the series of glycols as a water-soluble depressant, glycerin as a trihydric alcohol and a package of inhibiting additives in the following ratio of components, wt. %:

Monohydroxy alcohol 52.5-80.0 Dihydric alcohol 8.0-20.0 Trihydric alcohol 8.0-27.0 Inhibitor Pack no more than 5.0,

the mixture of alcohols is taken in the ratio of monatomic, diatomic, triatomic equal to 3.0 ÷ 10.0: 1.0: 1.0 ÷ 1.5, respectively; at least one selected from the series is used as the monohydric alcohol: methyl, ethyl, isopropyl in any ratio; at least one selected from the series is used as the dihydric alcohol: ethylene glycol, propylene glycol, diethylene glycol in any ratio; the package of inhibitory additives in the form of an aqueous composition contains: octanoic acid, tolyltriazole, nonanoic acid, borax, sebacic acid, sodium hydroxide and water with a balanced ratio of these components, with a composition density at 20 ° C in the range of 1.30-1.40 g / cm ³ and a hydrogen index (pH) in the range of 9.0-11.0.

The use of the concentrate as a means to reduce the temperature of the onset of crystallization of the coolant, while the effectiveness of reducing the temperature when using it reaches up to 20 ° C with a ratio of funds to coolant equal to 1: 6 ÷ 16. The use in the composition of the concentrate of new components in combination with the known ones and their optimal ratio found led to an unexpected result, namely, a new use of the concentrate as a means to reduce the temperature of crystallization onset of operational coolants, which improves the temperature characteristics of the coolant.

The product retains fluidity at temperatures below minus 75 ° C; has a kinematic viscosity at minus 40 ° C when using aliphatic alcohol of the C ₁ range _of 6.0 mm ² / s, 54 mm ² / s for C ₂ and 101.1 mm ² / s for C ₃ . For the preparation of the concentrate, components are used that are produced by both domestic and foreign manufacturers. For example, sebacic acid according to GOST 15582-84, sodium hydroxide according to GOST 2263-79, benzotriazole according to TU 6-09-805-63, ethylene glycol - GOST 19710-83, octanoic acid - import, nonanoic acid - import, borax - import.

The content of the components in the package of inhibitory additives in terms of their content in the product is in total not more than 5.0 wt.%, While octanoic acid is 0.16-0.3; tolyltriazole - 0.07-0.14; nonanoic acid - 0.05-0.11; borax - 0.6-0.9; sebacic acid - 0.09-1.0; sodium hydroxide - 0.18-0.35 and water 1.85-2.2.

The preparation of the concentrate is carried out by sequential mixing of the components at a temperature not exceeding 40-45 ° C.

The temperature of the onset of crystallization of the concentrate and coolant is determined by the method of GOST 28084.

The invention is supported by example.

Example 1

97 wt.% Of a mixture of liquid alcohols in the ratio monatomic - methyl: diatomic - (mono) ethylene glycol: triatomic - glycerol in the ratio 3: 1: 1.5 is placed in a container with a stirrer, while monohydric alcohol is 52.5%, diatomic 17 , 5%, glycerol 27%, add a package of inhibitory additives, 3 wt.%, Which includes the following components: octanoic acid - 0.16; tolyltriazole - 0.07; nonanoic acid - 0.05; Buru - 0.60; sebacic acid - 0.09; sodium hydroxide - 0.18 and water - 1.85. The number of components of the additives corresponds to their content in the tool. The density of the additive package is 1.35 g / cm ³ and the pH is 10.5.

The mixture is stirred at 40 ° C for 4 hours until the components are completely dissolved. The resulting concentrate, it is also a tool, is added to the test coolant with a temperature of crystallization onset minus 30 ° C in the ratio of 1: 6, 1: 8 and 1:16 coolant, after adding the tool the temperature decreased by 5-20 ° C.

Table 1 shows the effect of the ratio of the agent for lowering the crystallization temperature (CTC): the studied coolant on the physicochemical parameters, which practically do not change. Table 2 shows the influence of the initial temperature of the onset of crystallization of the studied coolant on the effectiveness of the HFCS at a ratio of HFC: OJ = 1: 8.

Example 2

96 wt.% Of a mixture of liquid alcohols in the ratio monatomic - isopropyl: diatomic - diethylene glycol: triatomic - glycerol in the ratio of 10.0: 1.0: 1.0 is placed in a container with a stirrer, while the monohydric alcohol is 80%, the diatomic 8% , glycerin 8%, add a package of inhibitory additives, 4 wt.%: octanoic acid - 0.20; tolyltriazole - 0.08; nonanoic acid - 0.07; borax - 0.80; sebacic acid - 0.10; sodium hydroxide 0.25 and water 2.50. The number of components of the additives corresponds to their content in the tool. The density of the additive package is 1.30 g / cm ³ and the pH is 11.0.

The mixture is stirred at 45 ° C for 4 hours until the components are completely dissolved. The resulting agent is added to the coolant under study with a crystallization onset temperature of minus 30 ° C in a ratio of 1: 6, while the crystallization onset temperature decreases by 17 degrees, i.e. becomes equal to minus 47 ° C.

Example 3

A 95 wt.% Mixture of liquid alcohols in the ratio monohydric - ethyl: diatomic - propylene glycol: triatomic - glycerol equal to 3.0: 1.0: 1.0 is placed in a container with a stirrer, while monohydric alcohol is 57%, diatomic 19% , glycerol 19%, add a package of inhibitory additives, 5 wt.%: octanoic acid - 0.30; tolyltriazole - 0.14; nonanoic acid - 0.11; borax - 0.90; sebacic acid - 1.0; sodium hydroxide - 0.35 and water 2.20.

The obtained agent is added to the test coolant with a crystallization onset temperature of minus 20 ° C in a ratio of 1:16 and 1: 8, and the crystallization onset temperature decreases by 7 and 17 degrees, respectively, i.e. becomes equal to minus 27 ° C and minus 37 ° C.

Similar results were also obtained when using funds with other ratios of components according to the claimed combination of features in the formula, while the pH and alkalinity of the coolant remain almost unchanged.

At the level of analogues and prototype, all other operational characteristics of the product are preserved, such as inhibitory ability, chemical stability, inertness to rubber products, the ability to prevent mineral deposits in closed water systems, prevent the oxidation of all alcohols that make up the product and coolant, etc.

Thus, the proposed tool allows to reduce the temperature of the onset of crystallization of operational coolants by 5-20 degrees, which expands the possibilities of using coolant, increase the resource of internal combustion engines and heating systems.

Table 1 No. Indicator Initial test coolant Coolant after the addition of CTC in the ratio of CTC: COOL 1: 6 1: 8 1:16 one Crystallization onset temperature, ° C Minus 30 Minus 50 (for C ₁ ) ^* Minus 45 (for C ₃ ) ^** Minus 42 (for C ₁ ) Minus 40 (for C ₃ ) Minus 36 (for C ₁ ) Minus 35 (for C ₃ ) 2 PH, units pH 7.7 7.8 7.7 7.7 3 Alkalinity, cm ³ 12.1 12.3 12,2 12.1 *) - the data are given for the use of monohydric alcohol of the aliphatic series C ₁ . **) - the data are given for the use of a monohydric alcohol of the aliphatic series C ₃ .

table 2 No. Indicator The initial temperature of the onset of coolant crystallization Minus 30 Minus 35 Minus 40 one The temperature of the onset of crystallization after the addition of CTC, ° C Minus 42 (for C ₁ ) ^* Minus 49 (for C ₁ ) Minus 60 (for C ₁ ) Minus 40 (for C ₃ ) ^** Minus 47 (for C ₃ ) Minus 54 (for C ₃ ) 2 The decrease in the temperature of crystallization onset, Δ (Δ = Tkr-Tkr, ref), ° С 12 (for C ₁ ) 14 (for C ₁ ) 18 (for C ₁ ) 10 (for C ₃ ) 12 (for C ₃ ) 14 (for C ₃ ) 3 ^*** PH value at 20 ° C 7.7 / 7.7 7.8 / 7.8 8.5 / 8.5 4 ^*** Alkalinity, cm ³ 12.1 / 12.2 12.7 / 12.8 15.2 / 14.9 *) - the data are given for the use of a monohydric alcohol of the aliphatic series C ₁ . **) - the data are given for the use of a monohydric alcohol of the aliphatic series C ₃ . ***) - through a fraction the data for the original coolant and coolant after the addition of HFS are given.

Claims (7)

1. Concentrate to improve the temperature characteristics of the coolant, containing a monohydric alcohol from the C ₁ -C ₃ series, a dihydric alcohol from the series of glycols as a water-soluble depressant, glycerin as a trihydric alcohol and a package of inhibitory additives in the following ratio, wt.%:
monohydroxy alcohol 52.5-80.0 dihydric alcohol 8.0-20.0 trihydric alcohol 8.0-27.0 inhibitory package no more than 5,0 2. The concentrate according to claim 1, characterized in that it contains a mixture of alcohols in the ratio: monoatomic, diatomic, triatomic, equal to 3.0-10.0: 1.0: 1.0-1.5, respectively. 3. The concentrate according to claim 1, characterized in that at least one selected from the series is used as the monohydric alcohol: methyl, ethyl, isopropyl in any ratio. 4. The concentrate according to claim 1, characterized in that at least one selected from the series is used as the dihydric alcohol: ethylene glycol, propylene glycol, diethylene glycol in any ratio. 5. The concentrate according to claim 1, characterized in that the package of inhibitory additives in the form of an aqueous composition contains: octanoic acid, tolyltriazole, nonanoic acid, borax, sebacic acid, sodium hydroxide with a balanced ratio of these components with the density of the composition at 20 ° C within 1.30-1.40 g / cm ³ and a hydrogen index (pH) in the range of 9.0-11.0. 6. The use of the concentrate according to any one of claims 1 to 5 as a means to lower the temperature at which crystallization of the coolant begins. 7. The use of the concentrate according to claim 6, characterized in that the efficiency of lowering the temperature when using the agent reaches up to 20 ° C with a ratio of the agent to the coolant equal to 1: 6-16.