FI112799B - Use of an aqueous solution comprising trimethylglycine as hydraulic fluid - Google Patents

Abstract

The present invention relates to the use of a water based fluid composition as a hydraulic fluid. The fluid composition is particularly suitable for conditions with temperatures lower than 0 DEG C. The fluid composition comprises from 1 to 60% by weight of trimethyl glycine or salts of a trimethyl glycine hydrate or derivativesof trimethyl glycine or mixtures thereof, from 40 to 99% by weight of water and optionally additives.

Description

112799

Use of an aqueous solution containing trimethylglycine as a hydraulic fluid Anhydrous av en vattenlösning omfattande trimethylglycin som hydraulikvätska 5

The present invention relates to the use of an aqueous liquid composition as a hydraulic fluid and as a lubricating fluid, shear fluid or drilling fluid. The liquid composition is particularly suitable for conditions where the temperature may drop below 0 ° C.

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Hydrostatic transmission was invented more than 90 years ago, but the materials used at the time were not suitable for continuous use. The benefits of water are non-toxic, inexpensive, non-flammable, safe and easy to use, and there are no environmental problems with using the water. Indeed, hydro-hydraulics systems have recently been heavily developed to replace similar oil-based systems, as industry is increasingly demanding cleaner processes without undesirable environmental impacts. In addition, any leakage of hydraulic oil from the oil-based system may spoil the products being manufactured, resulting in many components using mechanical transmission components to provide power at the application.

Hydraulic hydraulics systems consist, as in conventional hydraulics, of: * - pump units with tanks, rotary and linear actuators, and actuator control and protection valves. Conventional tap water is used as power transmission medium and 25 for lubrication. The components used in water hydraulics systems are of a material and quality suitable for use with, in particular, ordinary potable water. However, water has some of the crucial drawbacks of water hydraulics systems. Water freezes at temperatures that; are below 0 ° C. In addition, water causes corrosion on metal surfaces, especially in the presence of iron-containing substances, and microbes can grow in the water, which can cause equipment contamination and malfunctions. Water lubricating properties are not optimal.

Aqueous solutions of ethylene glycol and propylene glycol can be used at temperatures below 0 ° C in aqueous hydraulics systems. Frequently used as antifreeze glycols, these glycols cause corrosion problems and, when evaporated, emit an unpleasant odor along with the air stream, some with high viscosity and quite considerable toxicity. In addition, their use, especially in the food industry, has recently been restricted. The disadvantage of ethylene glycol is its toxicity and low environmental friendliness. Indeed, propylene glycol is often used in place of ethylene glycol in applications where less toxic properties are required. However, propylene glycol is an environmentally polluting compound which has the disadvantage of having a large increase in viscosity at low temperatures. Used oil-based or glycol-based hydraulic fluids must be disposed of at a hazardous waste disposal plant.

Typical compositions of water-based hydraulic fluids (HF-C fluids) contain 15-30% high-viscosity polyether glycol and 35-45% '·' water with up to 50% simple glycol and small amounts • '' known additives. In general, the goal is to reduce; t Hydraulic fluids with a polyether glycol content of 10% or lower, and manufactures products called "High Water Based Fluids" (HWBFs), typically containing 50% to 98% water, by removing some of the glycol or glycol .

25 ··, From the foregoing, it can be seen that there is an obvious need for hydraulics hydraulics as a hydraulic fluid as well as a biodegradable aqueous liquid-1 'synthetic lubricant, shear fluid and drilling fluid that can also be used at temperatures below 0 ° C. : 30 non-toxic and non-corrosive.

3, 112799

FI 99260 describes a heat transfer / coolant containing 15-50% trimethylglycine or derivatives thereof and 50-85% water. Patent application FI 973551 describes the use of an aqueous liquid solution of trimethylglycine in wetting and spray cooling systems and patent application FI 973552 5 describes the use of a liquid containing trimethylglycine or derivatives thereof and water for the freezing of aircraft and runways.

It is an object of the present invention to use an aqueous liquid composition for aqueous hydraulics systems as hydraulic fluid as well as lubricating fluid, cutting fluid and drilling fluid. The liquid is also suitable for use at temperatures below 0 ° C and can solve or substantially reduce the problems and drawbacks of prior art solutions.

The use of a liquid composition according to the invention as a hydraulic fluid for water hydraulics systems is characterized in what is claimed.

It has been found that aqueous solutions containing trimethylglycine or derivatives thereof can be used in hydraulic hydraulics systems and equipment for continuous use as hydraulic fluid, lubricating fluid, cutting fluid and drilling fluid, also at temperatures below 0 ° C. An aqueous liquid composition according to the invention, 1. comprises trimethylglycine (anhydrate or hydrate) or salts of trimethylglycine hydrate or trimethylglycine derivatives or combinations thereof. Preferred '; the compound is trimethylglycine or betaine. Betaine can be prepared synthetically as well as, for example, by isolation from naturally occurring products such as sugar beet; 25 rich, which enables the production of hydro-hydraulic fluid, lubricating fluid, cutting fluid and drilling fluid of biological origin and low life cycle.

:. According to the invention, a liquid composition suitable for use in water hydraulics and hydraulic fluid as well as lubricating fluid, cutting fluid and drilling fluid. comprises from 1 to 60% by weight, preferably from 20 to 35% by weight, of trimethylglycine or trimethylglycine dihydrate salts or trimethylglycine derivatives or combinations thereof and 4112799 40 to 99% by weight of water. Suitably the water in the liquid composition is deionized water or potable tap water, preferably deionized water.

If desired, additives such as stabilizers, corrosion inhibitors, viscosity and surface tension adjusting agents may be added to the liquid composition, if desired, in conventional amounts known in the art for aqueous hydraulics, lubricants, shear fluids and drilling fluids. Compounds that are not harmful to the environment are preferably used. Some suitable additives are shown in the sieve.

Anti-wear agents reduce wear on metal parts. Examples of conventional anti-wear agents are zinc dialkyl thiophosphate and zinc diaryl thiophosphate. Anti-wear compounds are also typically metal or amine salts of organic sulfur, phosphorus or boron derivatives or carboxylic acids. These include, for example, salts of C1-22 aliphatic or aromatic carboxylic acids, sulfuric acids such as aromatic sulfonic acids, phosphoric acids, acidic phosphate esters and analogous sulfur compounds such as'. salts of thiophosphoric acid and dithiophosphoric acid.

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Corrosion inhibitors, also known as corrosion inhibitors, reduce the degradation of metal parts in contact with the liquid composition. Examples of corrosion inhibitors are phosphosulfurized hydrocarbons and products obtained by reacting phosphosulfurized hydrocarbons with alkaline earth metal oxide or hydroxide. The metal corrosion inhibitors may also be other organic or inorganic compounds such as metal nitrides, hydroxylamines, neutralized fatty acid carboxylates, phosphates, sarcosines and succinimides etc. Amines such as alkanolamines, e.g. ethanolamine and diethanolamine are useful. Non-ferrous metal type inhibitors include, for example, aromatic triazoles.

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A surfactant may be included in the composition as a thickening agent, which may be nonionic, cationic, anionic or amphoteric. Examples of suitable surfactants are linear alcohol alkoxylates, nonylphenol ethoxylates, fatty acid soaps, amine oxides, etc.

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Antifoam agents are used to control the antifoam. The foaming can be controlled with high molecular weight dimethylsiloxanes and polyethers. Some examples of polysiloxane-type antifoam agents are silicone oil and polydimethylsiloxane.

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Detergents and metal rust inhibitors include metal salts of sulfonic acids, alkyl phenols, sulfurized alkyl phenols, alkyl salicylates, naphthenates, and other oil-soluble mono- and dicarboxylic acids. Highly basic metal salts such as highly alkaline earth metal sulfonates (especially Ca-15 and Mg salts) are often used as detergents.

Examples of suitable viscosity adjusting agents are all types known in the art, such as polyisobutylene, copolymers of ethylene and propylene, copolymers of methacrylate, methacrylate, butyric acid, unsaturated dicarboxylic acid and styrene copolymers and partially hydrogenated copolymers of isoprene / butadiene and partially hydrogenated homopolymers of butadiene and isoprene.

Antioxidants include the alkaline earth metal salts of alkyl phenolthio thioesters, preferably having a C5-C12 alkyl side chain, eg, calcium nonylphenol sulfide,> · ',! bariumoctylphenylsulfide, dioctylphenylamine, phenylalphanaphthylamine, phospho-sulfurized or sulfurized hydrocarbons, etc.

«* '; Friction control agents can be used to control the frictional properties of a liquid composition. Examples of suitable friction control agents are fatty acid esters and amides, molybdenum complexes of polyisobutenyl succinic anhydride amino alcohols, glycerol esters of dimerized fatty acids, alkane phosphonic acid dihydroxy, lower alkyl 1-phosphites and epoxides; and alkyleneoxy-5-diaddithio products of phosphosulfurated N- (hydroxyalkyl) alkenylsuccinimides.

Dispersants retain as a suspension in the liquid composition insoluble materials formed as a result of in-use oxidation, thereby preventing flocculation and precipitation or deposition of metal parts.

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The swelling agents for the gaskets are mineral oils which cause swelling of the gaskets in the engine and equipment and include Cg-Cu aliphatic alcohols such as tridecyl alcohol.

In addition, the liquid composition may also contain other components such as border lubricants, high pressure additives, colorants, perfumes, antimicrobial agents and the like, which are well known to those skilled in the art.

: * The following Table I estimates the trimethylglycine and ethylene glycol and; 20 toxicity of propylene glycol based on LD50 values in the literature. The LD 50 values used have been tested in rats orally.

Table I

Compound LD50 / mg / kg

Ethylene glycol 4,700

Propylene Glycol 20,000 '' Trimethylglycine 11,200; · '25: Waterproofing Liquid Waterproofing Composition for Waterproofing, Waterproofing, Waterproofing, jäätymättömyys. The liquid composition used in accordance with the invention is significantly less toxic and more environmentally friendly than the known oil and glycol based hydraulic fluids. It is not classified as hazardous waste and its easy disposal will reduce operating costs. Handling the liquid composition as waste does not require any special measures as it can be absorbed into the ground or drained.

The liquid composition containing trimethylglycine also has corrosion inhibiting properties. Corrosion refers to the wear of a material due to an electrochemical phenomenon. The voltage difference between the liquid and the solid causes the electrons to transfer between the materials. Electron transfer causes wear and thinning of the material. This rate of thinning is described as the corrosion rate of cor-15 in micrometers per year, pm / a. The corrosion rate can be measured by measuring the thinning of the raw material. Table II shows the effect of a 50% trimethylglycine liquid composition on the corrosion of metals to various materials:

TABLE II

i '· 20'; _ 1 Metal Thinning / 2 pm / a

Copper 1.5 ... 0.5

Carbon steel Fe52 75 ... 10 25 Brass 1,5 ... 0,2 * ·, ··. Red metal 125 ... 20

Cast Iron 0.9 ... 0.2> - ^ ___

A higher figure describes the corrosion rate at the beginning of the experiments, a lower figure over time for 30 well-established situations.

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The liquid composition is stable and suitable for use at temperatures from -50 ° C to +110 ° C, with a preferred operating temperature range of -15 ° C to + 30 ° C. Table III shows the kinematic viscosity of ethylene glycol, propylene glycol and trimethylglycine solutions at a freezing point of -15 ° C and 50% by weight. The freezing point is the temperature at which the first crystals form in solution.

Table III

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Liquid Concentration Kinematic viscosity wt% mm2 / s

Temperature 20 ° C -10 ° C -15 ° C

Ethylene glycol 30.5 2.1 4.3 6.5 8.2

Propylene Glycol 33 3.3 7.8 14.4 20

Trimethylglycine 35 2.1 5.1 11 17.2

Ethylene Glycol 50 3.48 7.40 11.7 19.6

Propylene Glycol 50 6.44 18.70 38 87

Trimethylglycine 50 5.90 12.80 21.50 38 ». , Trimethylglycine, or betaine, reduces the size of the water droplet that may be caused by trime; A hydrophobic methyl terminus and a hydrophilic acid terminus j 'of a styloglycine molecule; the influence. This allows the liquid to be used at temperatures below 0 ° C. Follow-; ; Table IV shows the effect of trimethylglycine on the freezing point, v, of the aqueous solution.

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Table IV

Liquid in 50% solution

freezing point, ° C

Ethylene glycol -35

Propylene Glycol -34

Trimethylglycine -40

The trimethylglycine-containing aqueous hyd-5 raulic liquid used in accordance with the invention does not freeze at temperatures of 0 to -50 °. Table V illustrates the effect of trimethyl liglycine on the freezing point of aqueous solutions.

Table V

Concentration of trimethylglycine, w / w Freezing point of solution, ° C

_ __ 20 25 ^ 2 _. 10.7 .. _ _ 50 ^ 40 10

The liquid composition used in accordance with the invention can be classified as flame retardant; ',' As a standard hydraulic, lubricating, shearing or drilling fluid due to its high water content. ". because of the kiss. This also makes the use of the liquid composition safe even under conditions of obvious flammability. Typically, hydraulic systems operate with fluids having a viscosity of ISO VG in the range 22 to 100 mm 2 / s. The viscosity of the liquid composition ISO VG ranges from 2 to 100 mm 2 / s. It is therefore suitable for use in hydraulic systems and as lubricating fluid for machines and equipment. The liquid composition is classified in the HEPR category according to ISO / TC 28 / SE4. In its application, the liquid composition acts as an energy transporter, lubricant, coolant, corrosion inhibitor, and equipment cleaner at the same time as defined in hydraulic lubricants 5.

The following Table IV compares the properties of ethylene and propylene glycol with those of the trimethylglycine solution at different temperatures.

10 TABLE IV

Comparison of the properties of some liquids at temperatures of + 20 ° C and -25 ° C.

Substance Freezing Temperature Density Specific Heat-Dynamic Point Thermal Conductivity Viscosity C C kg / m3 J / kg K W / mK 10A-3Ns / m2

Water δ 20 998 4180 0.63 0.65 -25

Ethylene Glyco-35 20 1066 3220 0.37 3.7 L 50% -25 1093 2940 0.34 32.2

Propylene -34 20 1038 3390 0.35 6.3 · · · · · · · · · · · · “glycol 50% -25 1070 3090 0.33 134 ′ Trimethylglyc -40 20 1090 2840 0.28 6.3; sine 50% -25 1113 2680 0.27 54.1 «'· · * 15 Trimethylglycine-based aqueous liquid composition is not favorable for microbial growth like water alone. Microbiological studies showed no growth of molds, yeasts and bacteria in aqueous solutions of trimethylglycine and above 20% by weight '*'; In solutions, trimethylglycine inhibits microbial growth.

The liquid composition containing trimethylglycine has surprisingly advantageous ointment properties compared to water alone.

"112799

Trimethylglycine is a non-toxic, naturally occurring raw material that lowers the freezing point of water. It does not necessarily require corrosion inhibitors to prevent corrosion, since it already possesses corrosion inhibiting properties. The surprising lubricating properties, stability, non-freezing and non-toxic properties of the liquid composition used in accordance with the invention make it very attractive to use as a hydraulic fluid in aqueous hydraulics systems and as a lubricating fluid, cutting fluid and drilling fluid. The liquid composition is therefore suitable for hydraulic systems, equipment, motors, pumps, lubricants and cutting and drilling fluids, especially for conditions requiring fire resistance, cold resistance and hydrodynamic lubrication. A very important property of a fluid composition for water hydraulics systems is its non-freezing at low temperatures to ensure reliable and smooth operation of the equipment.

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Claims (5)

112799 Use of an aqueous solution comprising trimethylglycine or salts of trimethylglycine hydrate or trimethylglycine derivatives, or combinations thereof, in hydroelectric applications and equipment. Use according to claim 1, characterized in that the aqueous solution comprising trimethylglycine comprises from 1 to 60% by weight of trimethylglycine or trimethylglycine hydrate salts or trimethylglycine derivatives or combinations thereof, from 40 to 99% by weight of water and optionally additives. Use according to claim 1 or 2, characterized in that the aqueous solution comprising trimethylglycine comprises from 20 to 35% by weight of trimethylglycine or salts of trimethylglycine hydrate or trimethylglycine derivatives or combinations thereof and optionally additives. Use according to claim 2 or 3, characterized in that the additives are selected from stabilizers, corrosion inhibitors, viscosity adjusters, surface tension adjusters, anti-wear agents, thickeners, anti-foaming agents, detergents, antioxidants, anti-friction agents, , cross-border lubricants, high pressure agents, colorants, perfumes and antimicrobial agents. Use according to any one of claims 1 to 4, characterized in that the aqueous solution comprising trimethylglycine or salts of trimethylglycine hydrate or trimethylglycine derivatives or combinations thereof is biodegradable, has an LD 50 greater than 11000 mg / kg, it has a freezing point of about -40 ° C in a 50% (w / w) aqueous solution and has an ISO VG viscosity of 2 to 100 mm 2 / s. ': 30, 3 112799