JP3233491B2 - Hydrated hydraulic fluid - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-containing hydraulic fluid composition which is a kind of a flame-retardant hydraulic fluid, and more particularly to a water-containing hydraulic fluid composition having excellent pump performance and wastewater treatment performance, and further having excellent performances such as stability. It relates to a hydraulic fluid composition.

[0002]

2. Description of the Related Art Hydraulic devices have been widely adopted by industry,
It contributes to improving productivity. These hydraulic devices are driven by hydraulic oil, but when used near heat sources, such as devices that handle high-temperature metals, devices that generate electric sparks, and heating furnaces, there is a risk of fire, so various types of flame-retardant operating devices are used. Oil is used. Among these flame retardant hydraulic oils, hydrous hydraulic fluids are widely used because of their low cost and excellent flame retardancy. A typical example of the water-containing hydraulic fluid is a water-glycol hydraulic fluid, and its types include a solution type and an emulsion type. The emulsion type has a concern about separation and decay, whereas the solution type water-glycol hydraulic fluid does not have a concern about separation and decay and has excellent performance such as nonflammability and high temperature stability. I have.

[0003] However, it is known that the conventional water-glycol type hydraulic fluid has the above-mentioned excellent performance, but has a problem in wastewater treatment. That is, when the water-glycol hydraulic fluid leaks from the hydraulic system and mixes with the wastewater, the COD component cannot be removed by the ordinary wastewater treatment methods such as the coagulation sedimentation method and the activated sludge method, and the pollution control is not possible. There's a problem. In the wastewater treatment of a water-containing hydraulic fluid, glycols are particularly problematic in the composition of the water-glycol hydraulic fluid. Glycols commonly used in water-glycol-based hydraulic fluids cannot be separated by coagulation and sedimentation because they are water-soluble, and high molecular weight glycols are extremely difficult to decompose by activated sludge treatment. is there. For this reason, methods such as separation by adsorption on activated carbon or the like and membrane separation have been studied in some cases, but their practical use has not been advanced due to the problems of processing speed and processing cost. A flame-retardant lubricating oil comprising polyoxyalkylene glycol diether, polyoxyethylene glycol monoether, and water has been proposed as a lubricating oil having improved wastewater treatment properties (Japanese Patent Publication No. 23240/1986). However, since this lubricating oil uses water-soluble polyoxyethylene glycol monoether at a high ratio of 10 to 45 wt%, the coagulation and sedimentation treatment is poor, and the wastewater treatment is still insufficient. Can not.

On the other hand, the hydrous working fluid must have excellent pump performance as well as waste water treatment performance. However, none of the conventional hydrous hydraulic fluids has both excellent wastewater treatment performance and excellent pump performance.

[0005]

SUMMARY OF THE INVENTION The present invention has excellent flame retardancy equivalent to that of a water-glycol type hydraulic fluid, and has stability, corrosion resistance and abrasion resistance. It is an object of the present invention to provide a water-containing hydraulic fluid composition having a coagulation-sedimentation treatment property and excellent pump performance.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in order to solve the above-mentioned problems, and as a result, a specific polyoxyalkylene glycol monoether compound has been substituted for the polyoxyethylene glycol monoether compound. Focusing on using, as a result of further research, by combining a specific polyoxyalkylene glycol monoether compound and a specific fatty acid salt, stability,
It has various properties such as corrosion resistance and flame retardancy, and even when mixed in wastewater, the base compound is separated from the water without dissolving in a large amount of wastewater, and practically does not dissolve in the wastewater. It has been found that the present invention exhibits excellent coagulation and sedimentation treatment properties and also exhibits excellent pump performance, and has completed the present invention.

That is, the present invention relates to (A) 5 to 40 wt% of a polyoxyalkylene glycol monoether compound represented by the following general formula (1), and (B) C6-C36 represented by the following general formula (2). 5-20 fatty acid salts
The present invention provides a hydrous hydraulic fluid characterized by containing wt% and (C) 40 to 90% by weight of water.
General formula (1):

[0008]

Embedded image R _1- [O (C ₃ H ₆ O) _a (C ₂ H ₄ O) _b H] _x (wherein, R ₁ is a monovalent or polyvalent hydrocarbon group having 3 to 20 carbon atoms) , A is the average addition mole number of propylene oxide and is 4 to 25, b is the average addition mole number of ethylene oxide, and when R ₁ has 3 to 6 carbon atoms, a / b
Is 18/2 to 75/2, and the carbon number of R ₁ is 7 to 10
A / b is from 8/2 to 65/2, and R ₁ is
When the number of carbon atoms is 11 to 20, a / b is 5/2 to 65.
/ A 2, x is an integer corresponding to the valence of R _1. )
General formula (2):

[0009]

Embedded image R ₂ COOM (wherein, R ₂ is a hydrocarbon group having 5-35 carbon atoms, M represents a salt-forming cation.)

Further, the present invention provides (A) the following general formula (1)
5 to 40% by weight of a polyoxyalkylene glycol monoether compound represented by the formula: (B) 5 to 20% by weight of a fatty acid salt having 6 to 36 carbon atoms represented by the following general formula (2):
(C) 37 to 89.9% by weight of water and (D) 0.1 to 3% by weight of a polyoxyalkylene glycol compound having an average molecular weight of 1,000 to 20,000 represented by the following general formula (3). A hydrous hydraulic fluid is provided. General formula (1):

[0011]

Embedded image R _1- [O (C ₃ H ₆ O) _a (C ₂ H ₄ O) _b H] _x (wherein, R ₁ is a monovalent or polyvalent hydrocarbon group having 3 to 20 carbon atoms) , A is the average addition mole number of propylene oxide and is 4 to 25, b is the average addition mole number of ethylene oxide, and when R ₁ has 3 to 6 carbon atoms, a / b
Is 18/2 to 75/2, and the carbon number of R ₁ is 7 to 10
A / b is from 8/2 to 65/2, and R ₁ is
When the number of carbon atoms is 11 to 20, a / b is 5/2 to 65.
/ A 2, x is an integer corresponding to the valence of R _1. )
General formula (2):

[0012]

R ₂ COOM wherein R ₂ represents a hydrocarbon group having 5 to 35 carbon atoms and M represents a salt-forming cation. General formula (3):

[0013]

HO (AO) H wherein AO represents a polyoxyalkylene group comprising an oxyethylene group and an oxypropylene group, and the weight ratio of the oxyethylene group to the polyoxyalkylene group is 5
5% or less. Hereinafter, the present invention will be described in detail.

In the hydrous working fluid of the present invention, a polyoxyalkylene glycol monoether compound represented by the general formula (1) (hereinafter sometimes referred to as compound A) is used as the component (A). R ₁ in the general formula (1) represents a monovalent or polyvalent hydrocarbon group, and includes an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, and an aromatic hydrocarbon group. Hydrocarbon groups are preferred. The carbon number of the monovalent or polyvalent hydrocarbon group is 3
-20, preferably 4-15. When the number of carbon atoms of the monovalent or polyvalent hydrocarbon group is less than 3, the compound A becomes water-soluble and adversely affects the coagulation / precipitation treatment property. On the other hand, when the number exceeds 20, the hydrophobicity of the compound A becomes too large. Since a solubilizing system is not formed, a working fluid having the intended performance of the present invention cannot be obtained. The valence of the monovalent or polyvalent hydrocarbon group may be appropriately selected, but is preferably monovalent to divalent.

The molar ratio a / b of the number of added moles a of propylene oxide and the number of added moles b of ethylene oxide is such that when R ₁ has 3 to 6 carbon atoms, a / b is 18/2 to 75 /
2, when R ₁ has 7 to 10 carbon atoms, a / b
Is 8/2 to 65/2, and the carbon number of R ₁ is 11 to 20.
If it is, a / b is 5 / 2-65 / 2. If it is less than these ranges, the hydrophilicity of the compound tends to be strong, and if it exceeds the range, the stability of the system tends to be poor.

The propylene oxide unit and the ethylene oxide unit may form a random structure or a block structure, and are represented by the following general formulas (4) and (5). Those that form a block structure are preferable, and those that form a block structure represented by the general formula (4) are particularly preferable. General formula (4):

[0017]

Embedded image R _1- [O- (C ₃ H ₆ O) _a- (C ₂ H ₄ O) _b -H] _x General formula (5):

[0018]

Embedded image R _1- [O- (C ₂ H ₄ O) _b- (C ₃ H ₆ O) _a -H] _x

The polyoxyalkylene glycol monoether compound represented by the general formula (1) has 3 to 3 carbon atoms.
It can be obtained by adding propylene oxide and propylene oxide to 20 monohydric or polyhydric alcohols. Specific examples of monohydric or polyhydric alcohols include:
For example, propanol, butanol, propylene glycol, butanediol, hexylene glycol, octylene glycol, glycerin, trimethylolpropane,
Examples include pentaerythritol, sorbitol, glucose, di (hydroxymethyl) cyclohexane, di (hydroxymethyl) benzene.

When the compound A used in the present invention is derived from a monohydric alcohol, the compound A is represented by the following general formula.

[0021]

R _1- [O (C ₃ H ₆ O) _a (C ₂ H ₄ O) _b ] -H In the above formula, R ₁ has 3 to 20 carbon atoms, preferably 4 to 15 carbon atoms.
Represents a hydrocarbon group. Examples of the hydrocarbon groups R _1, a linear or branched alkyl group or alkenyl group are preferred.
a represents an average polymerization mole number of propylene oxide, and 4
~ 25, preferably in the range of 4 ~ 20, b represents an average polymerization mole number of ethylene oxide,
The range is from 1 to 10, preferably from 1 to 5. Compound A may be used singly or may be used alone.
A combination of more than one species may be used.

In the hydrous hydraulic fluid of the present invention, (B)
As the component, a fatty acid salt of the general formula (2) (hereinafter sometimes referred to as compound B) is used. The general formula (2)
R ₂ in is a hydrocarbon group, preferably aliphatic hydrocarbon group. The aliphatic hydrocarbon group includes a linear or branched saturated or unsaturated hydrocarbon group.
The carbon number of this hydrocarbon group is in the range of 6 to 36, preferably in the range of 10 to 20. When the number of carbon atoms of the hydrocarbon group is less than 6, the solubilizing ability is reduced and the composition becomes unstable. When the number of carbon atoms exceeds 36, the viscosity is increased and the use as a working fluid becomes difficult.

M in the general formula (2) represents a salt-forming cation, and examples thereof include an alkali metal, ammonium and amine. As a specific example of M,
For example, sodium, potassium, lithium, ammonium, ethanolamine, diethanolamine, triethanolamine and the like, preferably sodium,
It is an alkali metal such as potassium. Specific examples of the fatty acid salt include, for example, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid,
Salts such as aromatic fatty acids and dimer acids are mentioned. In addition, the compound B may be used individually by 1 type, and may be used in combination of 2 or more type.

In the working fluid of the present invention, water is used as the component (C). As the water in this case, purified water is preferable. In the working fluid of the present invention, a polyoxyalkylene glycol compound represented by the general formula (3) (hereinafter sometimes referred to as compound D) is used as a component (D), if necessary. . In the general formula (3) representing the compound D, AO represents a polyoxyalkylene group comprising a copolymer of an oxyethylene group (C ₂ H ₄ O) and an oxypropylene group (C ₃ H ₆ O); The weight ratio of the oxyethylene group to the polyoxyalkylene group is 55% or less, and it is particularly preferable to define the weight ratio in the range of 30 to 55%.

The polyoxyalkylene group (A
In O), the oxyethylene group unit and the oxypropylene group unit may form a random structure or a block structure, but preferably have a block structure. As an example of such a block structure, (C ₃ H _{6
O) m - (C 2 H} 4 O) l - (C 3 H 6 O) n ( wherein, m, n
Represents the number of moles of the oxypropylene group, and l represents the number of moles of the oxyethylene group. ), (C ₂ H ₄ O) _q − (C ₃ H ₆ O) _p −
(C ₂ H ₄ O) _r (where q and r represent the number of moles of the oxyethylene group, and p represents the number of moles of the oxypropylene group). The average molecular weight of the polyoxyalkylene glycol compound represented by the general formula (3) is about 100
0 to 20,000, especially about 3,000 to 10,000
It is preferable to set it in the range of 000. When the weight ratio of the oxyethylene group to the polyoxyalkylene group in the general formula (3) exceeds 55%, the water solubility of the compound D becomes large, which adversely affects the coagulation-precipitation treatment property of the working fluid. Further, when the molecular weight of the compound D is less than about 1000, the viscosity of the working fluid becomes too low, while when the molecular weight exceeds about 20,000, the viscosity of the working fluid becomes too high. Compound D may be used alone or in combination of two or more.

The compounding ratio of each component in the hydrous hydraulic fluid of the present invention is as follows. When the hydrous hydraulic fluid comprises Compound A, Compound B and water, Compound A is 5 to 40% by weight, preferably 10 to 30% by weight. %, Compound B is 5 to 20% by weight, preferably 6 to 15% by weight. The amount of water is 40 to 9
0% by weight, preferably 55 to 86% by weight. When the hydrous hydraulic fluid is composed of compound A, compound B, water and compound D, compound A is 5 to 40% by weight, preferably 10 to 30% by weight.
%, Compound B is 5 to 20% by weight, preferably 6 to 1%.
5% by weight, water is 37-89.9% by weight, preferably 53%
８４84.9% by weight, compound D is 0.1-3% by weight, preferably 0.1-2% by weight. When the amount of compound A is less than 5% by weight, the viscosity decreases, and when it exceeds 40% by weight, the composition becomes unstable. When the amount of the compound B is less than 5% by weight, the composition becomes unstable, and when the amount exceeds 20% by weight, the viscosity is excessively increased. When the content of the compound D is less than 0.1% by weight, the viscosity decreases, and when it exceeds 3% by weight, the viscosity increases.

[0027] The viscosity of the hydrous hydraulic fluid composition of the present invention can be appropriately adjusted in accordance with the viscosity characteristics of the hydraulic fluid required in the hydraulic device used. In the hydrous working fluid of the present invention,
In addition to the above components, if necessary, other components, for example, sulfur compounds and phosphorus compounds as extreme pressure agents, hydroxides of alkali metals and amines as pH adjusters, mercaptobenzothiazole as a corrosion inhibitor, triazole and the like Auxiliary components such as metal salts and amine salts of nitrogen-containing compounds and metal salts of aminocarboxylic acids such as ethylenediaminetetraacetic acid as sequestering agents can be added in appropriate amounts. The hydrous working fluid of the present invention can be adjusted by appropriately mixing and mixing predetermined amounts of the respective components.

The hydraulic device that can use the hydrous hydraulic fluid of the present invention is not particularly limited, and may be a machine tool, a die casting machine, a transfer machine, a press machine, a forging machine, a cargo handling machine, a civil engineering construction machine. Various types of hydraulic devices such as plant control devices can be cited, and they are particularly effective in hydraulic devices such as devices that handle high-temperature metals with the danger of fire, devices that generate electric sparks, heating furnaces, and steel facilities. Also, the hydraulic pump used in the hydraulic device is not particularly limited, and various hydraulic pumps can be used.

[0029]

Next, the present invention will be described in more detail with reference to examples. Note that the present invention is not limited by these examples. Examples 1 to 5 Hydrous working fluids having the component compositions shown in Table 1 were prepared, and their performance was evaluated. Table 3 shows the results. The polyoxyalkylene glycol monoether compound and the polyoxyalkylene glycol compound used in Examples had a block structure in the polyoxyalkylene portion, and purified water was used as the water.

[0030]

[Table 1]

Comparative Examples 1 to 3 The performance of three commercially available water / glycol-based hydraulic fluids (I), (II) and (III) having a water content of 70% by weight or less was evaluated. Table 3 shows the results. These commercially available water / glycol based hydraulic fluids (I), (II) and (III) contain 35 to 45% by weight of water, 40 to 50% by weight of a solvent (glycol), and 10 to 15% by weight of a thickener. %,
Other additives have a composition of several% to 15% by weight.

COMPARATIVE EXAMPLE 4 The performance of a commercially available thickened high water content hydraulic fluid (IV) having a water content of 80 wt% or more was evaluated. Table 3 shows the results. The commercially available thickened high water content hydraulic fluid (IV) is a hydraulic fluid having a composition of 75 to 98% by weight of water, 1 to 15% by weight of a thickener and 1 to 10% by weight of other additives. .

Comparative Example 5 A hydrous working fluid having the composition shown in Table 2 was prepared, and the performance of the hydrous working fluid was evaluated. Table 3 shows the results.

[0034]

[Table 2]

The properties of the hydraulic fluid shown below were evaluated by the following test methods. (1) 1% aqueous solution of 100 parts by weight of the coagulation-sedimentation treatment test hydraulic fluid, after adding 1 wt% of aluminum sulfate _{(Al 2 (SO 4) 3} · 14~18H 2 O), the pH with aqueous NaOH 6. Adjust to 5. Thereafter, rapid stirring was performed for 10 minutes and slow stirring was performed for 15 minutes, and then the mixture was allowed to stand for 1 hour, filtered through a filter paper (5C), and then subjected to COD of the filtrate.
The value was measured. The treatment rate was calculated by the following formula, and the flocculation / sedimentation treatment property of the working fluid was evaluated based on the value. The higher the treatment rate, the more excellent the coagulation / sedimentation treatment property.

[0036]

(Equation 2)

[0037]

[Table 3]

The working fluids of the examples were subjected to a shell four-ball test (according to ASTM D-2783) and a metal corrosion test (according to JIS K 2234). The results are shown in Tables 4 to 7. (2) Shell four-ball test (based on ASTM D-2783) Measured under the following conditions. Conditions: 1200 rpm, 15 kg, 30 min

[0039]

[Table 4] (3) Metal corrosion test (based on JIS K 2234) Measured under the following conditions. Conditions: 70 ° C x 168 hours

[0040]

[Table 5]

[0041]

[Table 6]

[0042]

[Table 7] As is clear from the results of Tables 3 to 7, the hydrous hydraulic fluid compositions of the present invention all have sufficient performance as hydraulic fluids, and also have excellent coagulation and sedimentation treatment properties. I understand.

(4) Pump Performance Test Next, a pump performance test was performed on Example 5 and Comparative Example 4 using a hydraulic pump (PV2R2-26 manufactured by Yuken Kogyo Co., Ltd.) under the following conditions. Set pressure: 140 kgf / cm ² Number of revolutions: 1200 rpm Test time: 100 hr As a result of the pump performance test, the wear amount of the vane and the cam ring was 70.3 mg in Example 5, and 80.
2 mg.

[0044]

The hydrous hydraulic fluid of the present invention has excellent flame retardancy equivalent to that of a water-glycol hydraulic fluid and is required for a hydraulic oil having stability, corrosion resistance, abrasion resistance and the like. With properties that are excellent in various performances, and excellent in pump performance,
And it is excellent in coagulation sedimentation treatment in a wastewater treatment facility. Therefore, even if the aqueous working fluid of the present invention is mixed with wastewater, the base compound is separated from the water without dissolving in a large amount of wastewater, and is substantially insoluble in the wastewater. There is no particular hindrance to the processing.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI C10N 10:02 C10N 10:02 20:04 20:04 30:00 30:00 Z 30:06 30:06 30:12 30: 12 40:08 40:08 (72) Inventor Daisuke Yamada 1134-2, Gondogendo, Satte City, Saitama Prefecture Cosmo Research Institute, Inc. (72) Inventor Mayumi Yamamoto 1134-2, Gondogendo, Satte City, Saitama Prefecture Cosmo Research Institute R & D Center (58) Field surveyed (Int. Cl. ⁷ , DB name) C10M 173/02

Claims (2)

(57) [Claims] (A) a polyoxyalkylene glycol monoether compound represented by the following general formula (1):
0% by weight, (B) 5 to 20% by weight of a fatty acid salt having 6 to 36 carbon atoms represented by the following general formula (2), and (C) water 40
A water-containing hydraulic fluid characterized by containing about 90% by weight. General formula (1): embedded image R _1- [O (C ₃ H ₆ O) _a (C ₂ H ₄ O) _b H] _x (wherein, R ₁ is monovalent of 3 to 20 carbon atoms or A is a polyvalent hydrocarbon group, a is an average addition mole number of propylene oxide and is 4 to 25, b is an average addition mole number of ethylene oxide, and when R ₁ has 3 to 6 carbon atoms, a / B
Is 18/2 to 75/2, and the carbon number of R ₁ is 7 to 10
A / b is from 8/2 to 65/2, and R ₁ is
When the number of carbon atoms is 11 to 20, a / b is 5/2 to 65.
/ A 2, x is an integer corresponding to the valence of R _1. General formula (2): R ₂ COOM (wherein, represents a hydrocarbon group having 5 to 35 carbon atoms, and M represents a salt-forming cation). 2. A polyoxyalkylene glycol monoether compound represented by the following general formula (1):
0% by weight, (B) 5 to 20% by weight of a fatty acid salt having 6 to 36 carbon atoms represented by the following general formula (2), and (C) 37 to 8 water
9.9% by weight, and 0.1 to 3% by weight of a polyoxyalkylene glycol compound represented by the following general formula (3) and having an average molecular weight of 1,000 to 20,000. Hydrated hydraulic fluid. General formula (1): embedded image R _1- [O (C ₃ H ₆ O) _a (C ₂ H ₄ O) _b H] _x (wherein R ₁ is monovalent of 3 to 20 carbon atoms or A is a polyvalent hydrocarbon group, a is an average addition mole number of propylene oxide and is 4 to 25, b is an average addition mole number of ethylene oxide, and when R ₁ has 3 to 6 carbon atoms, a / B
Is 18/2 to 75/2 , and the carbon number of R ₁ is 7 to 10
A / b is from 8/2 to 65/2, and R ₁ is
When the number of carbon atoms is 11 to 20, a / b is 5/2 to 65.
/ A 2, x is an integer corresponding to the valence of R _1. R ₂ COOM (wherein, represents a hydrocarbon group having 5 to 35 carbon atoms and M represents a salt-forming cation). General formula (3): HO (AO) H (where AO represents a polyoxyalkylene group composed of an oxyethylene group and an oxypropylene group, and the weight ratio of the oxyethylene group to the polyoxyalkylene group is 5
5% or less. )