CN111849429A - Long-acting anhydrous anti-freezing solution for automobile engine - Google Patents

Abstract

The invention provides a long-acting anhydrous coolant for an automobile engine, which is prepared from the following components in percentage by mass: 92-95% of base liquid, 2.2-3.7% of 6- (N-allyl-1, 1,2, 2-tetrahydroperfluorodecyl) amine-2-mercapto-1, 3, 5-triazine-4-sodium mercaptide, 1.2-1.8% of medium-chain fatty acid, 2.5-3.5% of dipropylene glycol dimethyl ether and 0.002-0.004% of colorant; the base liquid is propylene glycol or/and ethylene glycol, and the medium-chain fatty acid is a mixed acid of monobasic fatty acid and dibasic fatty acid. The corrosion inhibitor is used for preventing metal corrosion, all parts of the whole system which can be contacted with a medium can be protected, and the cooling liquid has good heat conducting capacity, reduces local overheating and friction force of parts, enables fuel to be combusted more completely, improves the efficiency of the fuel and saves the oil quantity.

Description

Long-acting anhydrous anti-freezing solution for automobile engine

Technical Field

The invention belongs to the technical field of engine antifreeze, and particularly relates to a long-acting anhydrous antifreeze for an automobile engine and a preparation method thereof.

Background

The antifreezing fluid for engine is a cooling fluid containing special additive, and is mainly used for liquid-cooled engine cooling system, and possesses the excellent properties of preventing freezing in winter, preventing boiling in summer, preventing scale and corrosion all year round. Common antifreezing fluid for engines comprises water-ethylene glycol type antifreezing fluid and water-propylene glycol type antifreezing fluid, however, the boiling point of the aqueous antifreezing fluid is usually not higher than 110 ℃, and the problem of easy boiling exists. Compared with the water-containing antifreeze solution, the anhydrous engine antifreeze solution has the advantages of high boiling point, lower vapor pressure, no scale, quick temperature rise and the like, and is gradually replacing the traditional water-containing antifreeze solution.

At present, anhydrous antifreeze solutions are mainly mixed solutions obtained by adding various corrosion inhibitors to propylene glycol or ethylene glycol as a base solution. The following specific requirements are generally imposed on contact corrosion inhibitors for engines: firstly, a passivation film or other protective films can be generated instantly; secondly, the buffer effect is achieved on the pH value of the interface; thirdly, the hydrogen evolution reaction can be prevented and the hydrogen can be prevented from penetrating through the metal structure; and fourthly, the metal surface has surface activity and can replace water from the metal surface. The main function of the corrosion inhibitor is to prevent corrosion perforation of the metal substrate of the engine, thereby preventing seepage and loss of the antifreeze. Effective corrosion inhibitors slow or prevent corrosion at low concentrations. However, the protective action of the corrosion inhibitor has strict selectivity, and in order to realize the comprehensive protection of various metals in a cooling system, the selection and compounding of various corrosion inhibitors are required, which is a key point and a difficulty in the development of anhydrous anti-freezing solutions.

Disclosure of Invention

In view of the defects of the prior art, the invention aims to provide the long-acting anhydrous antifreeze solution for the automobile engine, which realizes safety, environmental protection, energy conservation and long acting of the antifreeze solution.

In order to achieve the technical purpose, the inventor considers that in an engine water-cooling system, antifreeze liquid needs to contact with various metals such as red copper, brass, steel, cast iron, cast aluminum and soldering tin at the same time, the corrosion behavior, adsorption and passivation characteristics of various metals are different, and the compounding of the corrosion inhibitor is needed to achieve the comprehensive protection of various metals in combination with the previous research experience. Secondly, the dosage and the compounding of the corrosion inhibitor are better when the dosage of the corrosion inhibitor is less on the premise of achieving effective corrosion inhibition, so as to reduce the corrosion prevention cost.

Based on this, the inventor researches a large number of compound corrosion inhibitors through experiments to improve the corrosion inhibition performance of the antifreeze solution, and finally obtains the following technical scheme:

the long-acting anhydrous antifreeze fluid for the automobile engine is prepared from the following components in percentage by mass: 92-95% of base liquid, 2.2-3.7% of 6- (N-allyl-1, 1,2, 2-tetrahydroperfluorodecyl) amine-2-mercapto-1, 3, 5-triazine-4-sodium mercaptide, 1.2-1.8% of medium-chain fatty acid, 2.5-3.5% of dipropylene glycol dimethyl ether and 0.002-0.004% of colorant; the base liquid is propylene glycol or/and ethylene glycol, and the medium-chain fatty acid is a mixed acid of monobasic fatty acid and dibasic fatty acid.

Further preferably, the long-acting anhydrous antifreeze fluid for automobile engines as described above, wherein the base fluid consists of propylene glycol and ethylene glycol. Still further preferably, the long-acting anhydrous antifreeze solution for automobile engines as described above, wherein the base solution is prepared from the following raw materials in a mass ratio of 1: (0.4-0.5) propylene glycol and ethylene glycol.

Further preferably, the long-acting anhydrous antifreeze fluid for automobile engines as described above, wherein said monobasic fatty acid is caprylic acid, and said dibasic fatty acid is selected from one of the following: suberic acid, azelaic acid, sebacic acid. Still further preferably, the long-acting anhydrous antifreeze solution for automobile engines as described above, wherein the mass ratio of the monobasic fatty acid to the dibasic fatty acid is 1 (1.2-3.5).

Most of the corrosion inhibitors have optimal concentration, and the excessive or insufficient consumption of the corrosion inhibitors is not beneficial to the exertion of the corrosion inhibition effect. After further optimization, the composition of each component of the long-acting anhydrous antifreeze fluid for the automobile engine is defined as follows: 92-95% of base liquid, 2.9-3.3% of 6- (N-allyl-1, 1,2, 2-tetrahydroperfluorodecyl) amine-2-mercapto-1, 3, 5-triazine-4-sodium mercaptide, 1.4-1.6% of medium-chain fatty acid, 2.6-3.0% of dipropylene glycol dimethyl ether and 0.002-0.004% of colorant; the base liquid is prepared from the following components in percentage by mass of 1: (0.4-0.5) propylene glycol and ethylene glycol.

Still further preferably, the long-acting anhydrous antifreeze solution for automobile engines is prepared from the following components in percentage by mass: 92.6 to 92.8 percent of base liquid, 3.0 to 3.2 percent of sodium 6- (N-allyl-1, 1,2, 2-tetrahydroperfluorodecyl) amine-2-mercapto-1, 3, 5-triazine-4-mercaptide, 1.4 to 1.5 percent of medium chain fatty acid, 2.6 to 2.8 percent of dipropylene glycol dimethyl ether and 0.002 to 0.004 percent of colorant; the base liquid is prepared from the following components in percentage by mass of 1: (0.4-0.5) propylene glycol and ethylene glycol.

In addition, the invention also provides a preparation method of the long-acting anhydrous antifreeze solution for the automobile engine, which comprises the following steps:

(1) adding medium-chain fatty acid into the basic solution, and stirring to dissolve and uniformly mix;

(2) adding 6- (N-allyl-1, 1,2, 2-tetrahydroperfluorodecyl) amine-2-mercapto-1, 3, 5-triazine-4-sodium mercaptide into the mixed solution obtained in the step (1), heating to 50-60 ℃, and stirring until the mixture is completely dissolved;

(3) and (3) adding dipropylene glycol dimethyl ether into the mixed solution obtained in the step (2), and stirring to uniformly mix to prepare the anhydrous antifreezing solution.

The invention has the following beneficial effects:

(1) the corrosion inhibitor is used for preventing metal corrosion, all parts of the whole system which can be contacted with a medium can be protected, and compared with any other corrosion prevention measures, the corrosion inhibitor has incomparable advantages.

(2) The antifreeze solution disclosed by the invention is free from icing, boiling, scale and corrosion when used, reduces the local overheating of an engine (the abrasion and friction of the engine are aggravated due to the local overheating) caused by poor heat conduction capability because a large amount of steam and bubbles are generated when the traditional antifreeze solution passes through the periphery of a combustion chamber due to low boiling point, and prolongs the service life of a circulating system and the engine.

(3) The antifreeze does not contain substances harmful to human and environment, the viscosity of the antifreeze changes along with the temperature, the internal temperature of an engine is balanced, the working condition of the engine is improved, fuel oil is combusted more fully, and the emission of tail gas is reduced.

(4) The antifreeze fluid has good heat conduction capability, reduces local overheating and friction force of parts, enables fuel to be combusted more completely, improves the efficiency of the fuel and saves the oil quantity.

(5) The antifreeze of the invention does not contain water and corrosive substances, does not generate corrosion and scale, and is provided with sufficient auxiliary supplementary substances to ensure the service life of the antifreeze.

Detailed Description

In order that the objects and advantages of the invention will be more clearly understood, the invention is further described in detail below with reference to examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not limit the scope of the invention. It should be noted that AF177N is sodium 6- (N-allyl-1, 1,2, 2-tetrahydroperfluorodecyl) amine-2-mercapto-1, 3, 5-triazine-4-mercaptide, and DPDM is dipropylene glycol dimethyl ether.

Examples 1 to 13: preparation of anhydrous antifreezing solution

Table 1: formula of anhydrous antifreezing solution (unit:%)

The preparation method comprises the following steps:

(1) weighing propylene glycol and ethylene glycol, mixing to obtain a base solution, adding caprylic acid into the base solution, uniformly mixing, adding sebacic acid, and stirring to dissolve;

(2) adding 6- (N-allyl-1, 1,2, 2-tetrahydroperfluorodecyl) amine-2-mercapto-1, 3, 5-triazine-4-sodium mercaptide into the mixed solution obtained in the step (1), heating to about 55 ℃, and stirring until the mixture is completely dissolved;

(3) and (3) adding dipropylene glycol dimethyl ether into the mixed solution obtained in the step (2), and stirring to uniformly mix to prepare clear and transparent anhydrous antifreezing solution.

Example 2: corrosion test of anhydrous antifreeze

By adopting glassware corrosion determination method (SH/T0085-. 3 parallel test pieces are adopted for each anti-freezing solution, after the test is finished, the test pieces are taken out, the anti-freezing solution is weighed again after being cleaned, and the mass loss average value of the test pieces before and after the test is recorded.

Table 2: weight loss of test piece (unit: mg)

Examples	Red copper	Brass	Steel	Cast iron	Cast aluminum	Soldering tin
							1	2.2	2.7	0.9	1.8	14.0	9.1
2	2.6	2.5	0.7	1.7	13.5	8.6
							3	2.3	2.2	0.8	1.5	13.4	8.7
4	2.0	2.2	0.5	1.4	13.5	8.5
							5	1.8	2.1	0.6	1.1	13.4	8.3
6	1.6	2.0	0.5	0.9	13.2	8.3
							7	1.5	1.9	0.5	0.8	13.0	8.3
8	15.7	14.5	7.9	10.3	33.9	36.5
							9	11.4	10.9	6.2	8.4	26.7	26.1
10	9.1	8.8	4.5	7.0	23.6	25.8
							11	2.1	2.3	0.8	0.9	13.4	8.6

Example 3: freezing point, boiling point and foam tendency test experiment of anhydrous antifreezing solution

Through detection, the freezing point of the anhydrous mixed solution prepared in the examples 1-11 is about-40 ℃ (the detection method is SH/T0090-1991), the boiling point is higher than 190 ℃ and is about 198 ℃ (the detection method is SH/T0089-1991). A foam tendency study was conducted on all the samples and it was found that the anhydrous anti-icing fluids of examples 1-10 all had a foam volume of less than 150mL and a foam disappearance of less than 5 seconds, whereas the anhydrous anti-icing fluid prepared in example 11 had a foam volume of 292mL and a foam disappearance of more than 10 seconds (test method SH/T0066-2002).

Claims (8)

1. The long-acting anhydrous coolant for the automobile engine is characterized by being prepared from the following components in percentage by mass: 92-95% of base liquid, 2.2-3.7% of 6- (N-allyl-1, 1,2, 2-tetrahydroperfluorodecyl) amine-2-mercapto-1, 3, 5-triazine-4-sodium mercaptide, 1.2-1.8% of medium-chain fatty acid, 2.5-3.5% of dipropylene glycol dimethyl ether and 0.002-0.004% of colorant; the base liquid is propylene glycol or/and ethylene glycol, and the medium-chain fatty acid is a mixed acid of monobasic fatty acid and dibasic fatty acid.

2. The long-acting anhydrous coolant for automobile engines according to claim 1, wherein the base fluid is composed of propylene glycol and ethylene glycol.

3. The long-acting anhydrous coolant for automobile engines according to claim 2, characterized in that the base liquid is prepared from the following components in a mass ratio of 1: (0.4-0.5) propylene glycol and ethylene glycol.

4. The long-acting anhydrous coolant for automobile engines according to claim 1, wherein the monobasic fatty acid is caprylic acid, and the dibasic fatty acid is selected from one of the following: suberic acid, azelaic acid, sebacic acid.

5. The long-acting anhydrous coolant for automobile engines according to claim 4, wherein the mass ratio of the monobasic fatty acid to the dibasic fatty acid is 1 (1.2-3.5).

6. The long-acting anhydrous coolant for the automobile engine according to claim 1, which is prepared from the following components in percentage by mass: 92-95% of base liquid, 2.9-3.3% of 6- (N-allyl-1, 1,2, 2-tetrahydroperfluorodecyl) amine-2-mercapto-1, 3, 5-triazine-4-sodium mercaptide, 1.4-1.6% of medium-chain fatty acid, 2.6-3.0% of dipropylene glycol dimethyl ether and 0.002-0.004% of colorant; the base liquid is prepared from the following components in percentage by mass of 1: (0.4-0.5) propylene glycol and ethylene glycol.

7. The long-acting anhydrous coolant for the automobile engine according to claim 6, which is prepared from the following components in percentage by mass: 92.6 to 92.8 percent of base liquid, 3.0 to 3.2 percent of sodium 6- (N-allyl-1, 1,2, 2-tetrahydroperfluorodecyl) amine-2-mercapto-1, 3, 5-triazine-4-mercaptide, 1.4 to 1.5 percent of medium chain fatty acid, 2.6 to 2.8 percent of dipropylene glycol dimethyl ether and 0.002 to 0.004 percent of colorant; the base liquid is prepared from the following components in percentage by mass of 1: (0.4-0.5) propylene glycol and ethylene glycol.

8. The method for preparing a long-acting anhydrous coolant for an automobile engine according to any one of claims 1 to 7, comprising the steps of:

(1) adding medium-chain fatty acid into the base solution, and stirring to dissolve and uniformly mix;

(2) adding 6- (N-allyl-1, 1,2, 2-tetrahydroperfluorodecyl) amine-2-mercapto-1, 3, 5-triazine-4-sodium mercaptide into the mixed solution obtained in the step (1), heating to 50-60 ℃, and stirring until the mixture is completely dissolved;

(3) and (3) adding dipropylene glycol dimethyl ether into the mixed solution obtained in the step (2), and stirring to uniformly mix to prepare the anhydrous cooling liquid.