CN106905932B - A kind of organic type engine coolant containing carboxylated graphene and preparation method thereof - Google Patents

Abstract

The invention discloses an organic type engine coolant containing carboxylated graphene and a preparation method thereof. The engine coolant includes the following components in parts by weight: 30-95 parts of glycol, 5-70 parts of deionized water, 0.03-3 parts of carboxylated graphene, 0.5-5.0 parts of organic acid corrosion inhibitor, 0.01-0.5 part of azole corrosion inhibitor, 0.001-0.01 part of defoamer, and 0.01-0.05 part of dye. The carboxylated graphene in the engine coolant of the invention and the organic acid corrosion inhibitor act synergistically to adsorb on the metal surface to form a dense carboxylated graphene/organic acid protective film, thereby preventing copper, brass, carbon steel, cast iron, Soldering tin and cast aluminum have comprehensive anti-corrosion effect, especially the heat transfer corrosion and cavitation corrosion performance of cast aluminum are excellent.

Description

A kind of organic type engine coolant containing carboxylated graphene and preparation method thereof

technical field

The invention relates to the field of engine coolant, in particular to an organic engine coolant containing carboxylated graphene and a preparation method thereof.

Background technique

Engine coolant is an indispensable part of maintaining the normal operation and operation of the engine. Coolant is the heat transfer medium of the engine cooling system, which plays the role of cooling, anti-corrosion, anti-scaling and anti-freezing. Coolant usually consists of water, antifreeze, corrosion inhibitor, scale inhibitor, colorant, defoamer, etc. According to the composition of the corrosion inhibitor, the engine coolant can be divided into inorganic type coolant based on inorganic salt corrosion inhibitor and organic type coolant based on organic acid corrosion inhibitor.

At present, inorganic coolants are mostly used in China, and the main inorganic salt corrosion inhibitors are silicates, borates, molybdates, phosphates, etc. Inorganic salt corrosion inhibitor mainly achieves the purpose of protecting the metal by passivating the metal surface and forming a passivation film. Inorganic salt corrosion inhibitors show the following weaknesses in the application process: (1) the consumption rate is fast, and additives need to be supplemented when used; (2) the passivation film generated is thick, and the thermal conductivity is poor, resulting in a decrease in heat dissipation performance; (3) ) The inorganic salt corrosion inhibitor has poor stability; (4) The environment is not friendly. The above-mentioned disadvantages limit the further wide application of inorganic type coolants.

The corrosion inhibitors of organic coolants that are widely used on the market mainly include monobasic organic acids and dibasic organic acids. The organic acid type corrosion inhibitor mainly changes the electrochemical properties of the metal surface through active adsorption on the metal surface, thereby preventing metal corrosion. Compared with inorganic corrosion inhibitors, the consumption of organic acid corrosion inhibitors is slow, and no supplementary additives are required. However, the adsorption film formed by the organic acid corrosion inhibitor is thin (only a few nanometers) and not dense, resulting in an unsatisfactory anticorrosion effect on solder and aluminum alloys, especially heat transfer corrosion of cast aluminum and cavitation corrosion of aluminum pumps.

SUMMARY OF THE INVENTION

The problem to be solved by the present invention is to provide a kind of organic engine cooling liquid containing carboxylated graphene, the carboxylated graphene in the cooling liquid and the organic acid corrosion inhibitor act synergistically, and have an ideal anti-corrosion effect on metals, In particular, the anti-corrosion effect of cast aluminum heat transfer corrosion and aluminum pump cavitation corrosion is remarkable.

In the first aspect, the present invention provides an organic type engine coolant containing carboxylated graphene, which, in parts by weight, comprises the following components: 30-95 parts of diol, 5-70 parts of deionized water, carboxyl group 0.03-3 parts of graphene, 0.5-5.0 parts of organic acid corrosion inhibitor, 0.01-0.5 part of azole corrosion inhibitor, 0.001-0.01 part of defoamer, and 0.01-0.05 part of dye.

The carboxylated graphene is graphene with carboxyl functional groups on the surface.

Preferably, the dihydric alcohol and deionized water form the base liquid of the cooling liquid, and in parts by weight, the organic type engine cooling liquid containing carboxylated graphene includes the following components: 100 parts of base liquid, 0.03-3 parts of carboxylated graphene, 0.5-5.0 parts of organic acid corrosion inhibitor, 0.01-0.5 part of azole corrosion inhibitor, 0.001-0.01 part of defoamer, and 0.01-0.05 part of dye.

Preferably, the organic engine coolant containing carboxylated graphene, in parts by weight, includes the following components: 55 parts of diols, 45 parts of deionized water, 0.2 parts of carboxylated graphene, 0.2 parts of organic 3.5 parts of acid corrosion inhibitor, 0.15 part of azole corrosion inhibitor, 0.01 part of defoamer, and 0.03 part of dye.

Preferably, the dihydric alcohol is one or more of ethylene glycol, 1,2-propylene glycol and 1,3-propylene glycol.

Preferably, the organic acid corrosion inhibitor includes a monocarboxylic acid and a dicarboxylic acid; the monocarboxylic acid is one or more of _C6 - _C10 monocarboxylic acids, and the dicarboxylic acid is One or more of C ₄ -C ₁₀ dicarboxylic acids.

The _C6 - _C10 monocarboxylic acid is a carboxylic acid with only one carboxyl group with 6-10 carbon atoms in the carbon chain; the _C4 - _C10 dicarboxylic acid is a carbon chain in the carbon chain A carboxylic acid having two carboxyl groups having 4 to 10 atoms.

Preferably, the azole corrosion inhibitor is one or both of benzotriazole and methyl benzotriazole.

Preferably, the defoamer is one of a silicone-based defoamer or an organic ether-based defoamer.

Preferably, the dye is at least one of acid lake blue, weak acid blue, rose red and bright yellow.

Monobasic organic carboxylic acid and dibasic organic carboxylic acid can form a protective film by adsorption on the metal surface, but the protective film is too thin and not dense, which is easy to corrode the metal, especially when the temperature is high and the gas is impacted. Therefore, the heat transfer corrosion of cast aluminum and the cavitation corrosion of aluminum pumps are poor in pure organic acid coolant. Pure graphene has poor wettability with water, alcohol and their mixtures, and cannot form a protective film by adsorption on the metal surface. The surface carboxylated graphene is compatible in water, alcohol and their mixtures; more importantly, using the carboxyl groups on the surface, carboxylated graphene can chemically bond with the metal to form a corrosion-resistant protective film on the metal surface. However, the protective film of pure carboxylated graphene has voids and is not dense. At this time, a monobasic organic carboxylic acid corrosion inhibitor and a dibasic organic carboxylic acid corrosion inhibitor with an appropriate proportion and appropriate carbon chain length are added. The carbon structure in carboxylated graphene and the carbon chain of the organic acid inhibitor (related to the length of the carbon chain and the branched structure of the carbon chain) are well adsorbed and stacked on the metal surface, forming a dense and flexible organic/inorganic hybrid Anti-corrosion protective film. The carboxylated graphene/organic acid protective film has good flexibility, and has quite high mechanical strength and hardness, so it has a good resistance to the impact pressure generated during the cavitation corrosion process; on the other hand, the formed carboxylated The thermal resistance between the graphene/organic acid protective film and the metal matrix is small, the protective film is thin and dense, and the thermal conductivity is very good, so the anti-corrosion effect on the heat transfer corrosion of cast aluminum is remarkable.

Compared with the existing engine coolant, the present invention has the following beneficial effects:

The carboxylated graphene and organic acid corrosion inhibitors in the cooling liquid act synergistically to produce chemical bonds on the metal surface to form a thin, dense and highly thermally conductive carboxylated graphene/organic acid protective film, thereby improving the comprehensive anti-corrosion effect on metals , especially cast aluminum heat transfer corrosion and aluminum pump cavitation corrosion;

Carboxylated graphene and organic acid corrosion inhibitors have good compatibility, good stability, slow consumption, longer service life, and environmental safety in water/glycol base liquid.

On the other hand, the present invention provides the above-mentioned preparation method of the organic type engine coolant containing carboxylated graphene, comprising the following steps:

(1) 30-95 parts by weight of dihydric alcohol and 5-70 parts by weight of deionized water are mixed and stirred to obtain a cooling liquid base liquid;

(2) adding 0.5-5.0 parts by weight of organic acid corrosion inhibitor and 0.03-3 parts by weight of carboxylated graphene to the base solution obtained in step (1), fully stirring until completely dissolved to obtain a first mixed solution;

(3) adding 0.01 to 0.5 parts by weight of an azole corrosion inhibitor to the first mixed solution obtained in step (2), and fully stirring until completely dissolved to obtain a second mixed solution;

(4) adding 0.001 to 0.01 parts by weight of defoaming agent to the second mixed solution obtained in step (3), and fully stirring to dissolve completely until a clear and transparent solution is obtained;

(5) Add 0.01-0.05 parts by weight of dye to the clear and transparent solution obtained in step (4), fully stir until completely dissolved, and finally obtain the cooling liquid product.

Preferably, in parts by weight, the organic engine coolant containing carboxylated graphene includes the following components: 100 parts of base liquid, 0.03 to 3 parts of carboxylated graphene, 0.5 parts of organic acid corrosion inhibitor ～5.0 parts, 0.01～0.5 part of azole corrosion inhibitor, 0.001～0.01 part of defoamer, 0.01～0.05 part of dye.

Preferably, the organic engine coolant containing carboxylated graphene, in parts by weight, includes the following components: 55 parts of diols, 45 parts of deionized water, 0.2 parts of carboxylated graphene, 0.2 parts of organic 3.5 parts of acid corrosion inhibitor, 0.15 part of azole corrosion inhibitor, 0.01 part of defoamer, and 0.03 part of dye.

Preferably, the dihydric alcohol is one or more of ethylene glycol, 1,2-propylene glycol and 1,3-propylene glycol.

Preferably, the organic acid corrosion inhibitor includes a monocarboxylic acid and a dicarboxylic acid; the monocarboxylic acid is one or more of C6-C10 monocarboxylic acids, and the dicarboxylic acid is C4-C10. One or more of C10 dicarboxylic acids.

Preferably, the azole corrosion inhibitor is one or both of benzotriazole and methyl benzotriazole.

Preferably, the defoamer is one of a silicone-based defoamer or an organic ether-based defoamer.

Preferably, the dye is at least one of acid lake blue, weak acid blue, rose red and bright yellow.

The preparation method has the advantages of simple process, low equipment requirements and low cost, and is favorable for industrial production.

Detailed ways

The beneficial effects of the present invention will be further described below in conjunction with examples and comparative examples.

1. Selection of raw materials used in the following examples

Carboxylated graphene: purchased from Nanjing Xianfeng Nanotechnology Company.

All other chemical reagents used in the examples were of analytical grade and were purchased from Qingdao Hailitai Chemical Reagent Co., Ltd.

2. Examples and data

Example 1

55kg of ethylene glycol and 45kg of distilled water are mixed and stirred to obtain a cooling liquid base liquid; 1.6kg of caprylic acid, 1.9kg of adipic acid, and 0.2kg of carboxylated graphene are added to the above-mentioned base liquid, and fully stirred to completely dissolve to obtain the first mixing solution; add 0.15kg of benzotriazole in the first mixed solution, fully stir until completely dissolved to obtain a second mixed solution; add 0.01kg of organosilicon defoamer to the second mixed solution, stir fully to completely dissolve To obtain a clear and transparent solution; add 0.03 kg of rose bengal dye to the above-mentioned clear and transparent mixed solution, fully stir until completely dissolved, and finally obtain cooling liquid product 1.

The composition of cooling liquid product 1 is: ethylene glycol 55kg, distilled water 45kg, carboxylated graphene 0.2kg, caprylic acid 1.6kg, adipic acid 1.9kg, benzotriazole 0.15kg, silicone defoamer 0.01kg, rose Red dye 0.03kg.

Example 2

60kg ethylene glycol, 35kg propylene glycol and 5kg distilled water are mixed and stirred to obtain cooling liquid base liquid; 1.4kg pimelic acid, 3.6kg isooctanoic acid are added in above-mentioned base liquid, and 3kg carboxylated graphene is fully stirred to dissolve completely to obtain the first A mixed solution; add 0.5kg of methyl benzotriazole to the first mixed solution, fully stir until completely dissolved to obtain a second mixed solution; add 0.01kg of organosilicon defoamer to the second mixed solution, stir well , so that it is completely dissolved until a clear and transparent solution is obtained; 0.05kg of acid lake blue dye is added to the above-mentioned clear and transparent solution, fully stirred until completely dissolved, and finally the cooling liquid product 2 is obtained.

The composition of the cooling liquid product 2 is: ethylene glycol 60kg, propylene glycol 35kg, distilled water 5kg, carboxylated graphene 3kg, isooctanoic acid 3.6kg, pimelic acid 1.4kg, methyl benzotriazole 0.5kg, silicone defoaming agent 0.01kg, acid lake blue dye 0.05kg.

Example 3

30kg propylene glycol and 70kg distilled water are mixed and stirred to obtain a cooling liquid base liquid; 0.15kg glutaric acid, 0.35kg caprylic acid, 0.03kg carboxylated graphene are added in the above-mentioned base liquid, and the first mixed solution is fully stirred until fully dissolved; Add 0.01kg of benzotriazole to the first mixed solution, stir fully until completely dissolved to obtain a second mixed solution; add 0.001kg of organic ether defoamer to the second mixed solution, stir fully, and completely dissolve until obtained Clear and transparent solution; add 0.01kg of bright yellow dye to the above-mentioned clear and transparent solution, fully stir until completely dissolved, and finally obtain cooling liquid product 3.

The composition of cooling liquid product 3 is: propylene glycol 30kg, distilled water 70kg, carboxylated graphene 0.03kg, caprylic acid 0.35kg, glutaric acid 0.15kg, benzotriazole 0.01kg, organic ether defoamer 0.001kg, bright yellow dye 0.01 kg.

Example 4

50kg of ethylene glycol and 50kg of distilled water were mixed and stirred to obtain a cooling liquid base liquid; 1.8kg of suberic acid, 1.4kg of capric acid, and 0.16kg of carboxylated graphene were added to the above-mentioned base liquid, and fully stirred until completely dissolved to obtain the first Mixed solution; add 0.12kg of methyl benzotriazole to the first mixed solution, fully stir until completely dissolved to obtain a second mixed solution; add 0.008kg of organosilicon defoamer to the second mixed solution, stir fully to make Completely dissolve to obtain a clear and transparent solution; add 0.02 kg of weak acid blue dye to the above-mentioned clear and transparent solution, fully stir until completely dissolved, and finally obtain cooling liquid product 4.

The composition of cooling liquid product 4 is: 50kg of ethylene glycol, 50kg of distilled water, 0.16kg of carboxylated graphene, 1.4kg of capric acid, 1.8kg of suberic acid, 0.12kg of methylbenzotriazole, 0.008 kg of silicone defoamer kg, weak acid blue dye 0.02kg.

3. Comparative example and performance test

For Examples 1-4 and the existing organic acid type cooling liquid and silicate type cooling liquid in the market, the anti-corrosion performance test was carried out according to GB-T 29743-2013, and the results are shown in Table 1:

The organic type coolant and silicate type coolant used in the comparative example are produced by Qingdao Compton Technology Co., Ltd. The type of silicate type coolant is CPC30-1, and the type of organic acid type coolant is CPC30- 2.

As can be seen from Table 1, the engine coolant of the present invention has comprehensive anti-corrosion properties to copper, brass, carbon steel, cast iron, solder, and cast aluminum; Compared with the coolant, it has more excellent heat transfer and anti-corrosion performance of cast aluminum alloy and anti-corrosion performance of aluminum pump cavitation. The anti-corrosion performance of the engine coolant prepared by the invention is obviously better than that of the existing silicate engine coolant and organic acid type engine coolant.

Table 1 Anti-corrosion performance test results

It should be understood that the above description of the preferred embodiments of the present invention is relatively detailed, and therefore should not be considered as a limitation on the scope of the patent protection of the present invention, and the patent protection scope of the present invention should be subject to the appended claims.

Claims (7)

1. an organic type engine coolant containing carboxylated graphene, by weight, comprising the following components: 100 parts of base fluids, 0.2 to 3 parts of carboxylated graphene, 3.5 to 5.0 parts of organic acid corrosion inhibitors , 0.15-0.5 part of azole corrosion inhibitor, 0.01 part of defoaming agent, 0.03-0.05 part of dye; wherein the base liquid is composed of 55-95 parts of dihydric alcohol and 5-45 parts of deionized water; the organic acid retarder The etchants are monocarboxylic and dicarboxylic acids. 2. the organic type engine coolant containing carboxylated graphene according to claim 1, is characterized in that, by weight, comprises the following components: 55 parts of glycols, 45 parts of deionized water, carboxylated 0.2 part of graphene, 3.5 parts of organic acid corrosion inhibitor, 0.15 part of azole corrosion inhibitor, 0.01 part of defoamer, and 0.03 part of dye. 3. The organic type engine coolant containing carboxylated graphene according to claim 1, wherein the dihydric alcohol is one of ethylene glycol, 1,2-propylene glycol and 1,3-propylene glycol species or several. 4. The organic type engine coolant containing carboxylated graphene according to claim 1, wherein the monocarboxylic acid is one or more of C6-C10 monocarboxylic acids, and the two The carboxylic acid is one or more of C4-C10 dicarboxylic acids. 5. the organic type engine coolant containing carboxylated graphene according to claim 1, is characterized in that, described azoles corrosion inhibitor is one of benzotriazole, methyl benzotriazole species or both. 6 . The organic type engine coolant containing carboxylated graphene according to claim 1 , wherein the defoamer is one of an organic silicon defoamer or an organic ether defoamer. 7 . 7. the preparation method of the organic type engine coolant containing carboxylated graphene as described in any one of claim 1-6, comprises the following steps: (1) 55～95 parts by weight of dihydric alcohol and 5～45 parts by weight of deionized water are mixed and stirred to obtain 100 parts by weight of cooling liquid base liquid; (2) adding 3.5-5.0 parts by weight of organic acid corrosion inhibitor and 0.2-3 parts by weight of carboxylated graphene to the base solution obtained in step (1), fully stirring until completely dissolved to obtain a first mixed solution; (3) adding 0.15-0.5 parts by weight of an azole corrosion inhibitor to the first mixed solution obtained in step (2), and fully stirring until completely dissolved to obtain a second mixed solution; (4) adding 0.01 parts by weight of defoaming agent to the second mixed solution obtained in step (3), fully stirring, and completely dissolving until a clear and transparent solution is obtained; (5) Add 0.03-0.05 parts by weight of dye to the clear and transparent solution obtained in step (4), fully stir until completely dissolved, and finally obtain the cooling liquid product.