DE1154220B - Process for incorporating a water-soluble solid into a lubricating grease - Google Patents

Description

According to one proposal, water-soluble solids can be converted into water-insoluble, non-dissolving solids Hydrocarbons or hydrocarbon mixtures, such as lubricating oils, heating oils and fuels, be dispersed by adding an aqueous solution of the solid with 0.5 to 5 percent by weight, calculated on the solid, a known emulsifier with the hydrocarbon or the hydrocarbon mixture emulsified into a water-in-oil type emulsion and the resulting water-in-oil emulsion thereupon is dewatered.

According to a further proposal, stable suspensions of organic and inorganic metal salts can be used are produced in a lubricating oil intended for the lubrication of diesel engines, by dissolving a salt of a divalent metal in such a solvent which is not or not completely miscible with the lubricating oil in question, together with an emulsifier in a lubricating oil to a stable emulsion with ao an average size of the dispersed Particles of preferably no more than 2 μ is emulsified, the ratio of the molecular Equivalents of emulsifier to the salt of a divalent metal is less than 1 and then thereafter the immiscible solvent is completely or largely removed from the emulsion.

When incorporating water-soluble solids in lubricating greases, the special problem of a Sufficient homogeneous and as fine as possible dispersion of the solid particles in the grease mass on, the dispersion once achieved also during the more or less long storage time of the grease and should be maintained during the use of the latter. In particular must be avoided that the solid particles subsequently become larger or grow, because on the one hand they tend to precipitate and on the other hand impair the lubricating effect of the grease.

It has now been found that this problem can be solved by combining various procedural measures can be solved satisfactorily, which ensure the desired effect only through their interaction.

The new method of incorporating a water soluble solid into a grease is thereby characterized in that an aqueous solution of the solid with an oil-soluble emulsifier from the Group of the organic salts of a polyvalent metal or those derived from organic acids Partial ester of a polyhydric alcohol with a method of incorporating a water-soluble one Solid into a grease

Applicant:

Bataafse Petroleum Maatschappij NV,
The hague

Representative: Dr. K. Schwarzhans, patent attorney,
Munich 19, Romanplatz 10

Claimed priority:
Great Britain, December 5, 1955 (No. 34 748)

Howard Daniel Moore, Chester, Cheshire,
and Richard Rigby, Saughall, Chester, Cheshire

(Great Britain),
have been named as inventors

Lubricating oil to form a water-in-oil emulsion emulsified, the emulsion formed is dehydrated by rapid evaporation and the suspension obtained is mixed with a grease at a temperature not exceeding 125 ° C.

The method according to the invention can be used to incorporate various types of water soluble solid substances are used in lubricating greases, including solid inorganic salts, solid Acids and solid organic substances. The procedure is especially valuable when using a lubricating grease Corrosion inhibitors or extreme pressure additives are to be incorporated.

Examples of water-soluble corrosion inhibitors are the alkali nitrites, such as sodium nitrite and potassium nitrite, Ammonium nitrite and the nitrites of amines, such as dicyclohexylammonium nitrite, as well as the corresponding Chromates, phosphates and iodates.

Arsenites, such as sodium or potassium arsenite, and the corresponding chromates, including sodium, ammonium and lithium chromate, the alkali carbonates including sodium carbonate and sodium bicarbonate, as well as the corresponding hypochlorites, silicates, chlorates and perchlorates can be applied. Also borates, like

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Borax, or boric acid, are suitable additives for lubricating oil, used when it comes to the partial ester lubricating greases, type acts, and in amounts of 0.01 to 5 weight as extreme pressure additives, which are water-soluble percent, in particular 0.1 percent by weight (calculated represent solid bodies, z. B. Oxyfett- as metal and based on the lubricating oil) if it acids, such as glycolic acid, lactic acid, a-oxycaproone, S are emulsifiers of the type of salts mehrwera-Oxyisobutter-, α-Oxyvalerien-, Ascorbin-, Berntiger metals are involved.

stone, oxal, maleic, aconite, glutacone and ci- It is often convenient to use a mixture of two or more

traconic acid, polyoxy fatty acids, such as glycerol, era such emulsifiers. A calcium

bon, gluconic, galactonic and mannonic acid, hy- or barium naphthasulfonate, combined with z. B.

hydroxylpolycarboxylic acids, such as citric, tartaric, tar ίο a calcium or barium salt of an aromatic

tronic and malic acid, organic salts such as sodium carboxylic acid or oxycarboxylic acid, which by a

benzoate and sodium acetate, amides, urea, ace or more alkyl groups with 8 or more carbons

tamide, thiourea, succinimide and maleic acid substance atoms is substituted, or with a calcium

amide, as well as amino acids such as glycine, alanine, cysteine, or barium salt of one by one or more alkyl

Glutamic acid and aspartic acid. 15 groups with 8 or more carbon atoms substituted

Mixtures of water-soluble solid phenols can also be used.

Substances according to the present process the lubricating mixtures of oil-soluble naphthasulfonates polyvalent

fats are incorporated. Metals with a partial ester of a polyvalent alcohol

When carrying out the process after the Erfin- hols are also well usable,

dung can be the aqueous solution of the water-soluble 20 The emulsions can be prepared by

solid body have any suitable concentration, simply adding the aqueous solution of the solid

z. B. from 1 percent by weight to the maximum solvent for the lubricating oil containing the emulsifier,

ability of the solid body in water. whereupon the mixture is stirred and then desired

The aqueous solution preferably contains 5 to, if homogenized, for example by adding

85 percent by weight of solids. The best ones carry out the emulsion by means of a gear pump

Results are obtained when the aqueous solution or a colloid mill.

gen a concentration of solids between 35. The aqueous solution is preferably in the and 65 percent by weight. Lubricating oil emulsified so intensely that the average these Solutions are preferably dispersed in a particle size of the aqueous Lö-lubricating oil emulsified of the same kind as that of 30 solution is no more than 2 microns. To this which forms the basis of the grease, which the way particularly resistant emulsions can er solids should be incorporated. The lubricating oil will hold in which the dispersed particles a mineral lubricating oil or a synthe- tized one can remain, d. H. don't clump together table hydrocarbon lubricating oil, such as polymeric or no flakes or agglomerates, ized olefins or alkylated aromatic compounds- 35 Removal of the water after the aqueous or a synthetic lubricating oil has been emulsified from the non-koh solution in the lubricating oil be of the hydrogen type, such as a silicone fluid or produced by rapid evaporation, a high boiling ester, e.g. B. Sebacic acid-di- takes place due to the presence of the emulsifiers (2-ethylhexyl) ester. The best results are obtained during water evaporation - provided achieved when 1 part by weight of the aqueous solution 4 ° that the water evaporates quickly - practically in 1 to 3 parts by weight of the lubricating oil no agglomeration of the dispersed particles emulsifies, However, care must always be taken to ensure that in this way there is a dispersion in the lubricating oil applied proportions in the absence of very fine particles of the solid, original Emulsifier used in individual cases formed into a body dissolved in water, and this Run water-in-oil emulsion. 45 particles are used in the manufacture of the The type of oil-soluble emulsifier is different from emulsifier used in constant susceptibility Meaning if the dispersion of the pension kept.

The size of these fine, solid particles depends on what they want to be moderate and stable. According to the invention, the size of the particles of the aqueous solution that were used before the oil-soluble emulsifiers are organic 50 which were present in the emulsion after evaporation, salts of polyvalent metals or organic partial esters of polyhydric alcohols derived from the concentration of the solid body in these acids. aqueous solution and also on the way in which the oil-soluble organic salts of alkaline earth metal- the water is removed from the emulsion. Suitable oils, especially calcium, are preferred. Methods for the rapid evaporation of water These salts can be derived from fatty acids, 55 are evaporation on a rotating heated cylinder such as stearic acid, aromatic carboxylic acids such as mill, equilibrium evaporation (flash evaporation alkylsalicylic acids, naphthenic acids or sulphonic acid) or spraying in a drying tower , in acids such as naphthasulfonic acids. Calcium naphtha- which the atomized emulsion is brought into contact with a hot sulfonate and calcium alkyl salicylate, especially gas stream, those with high basicity, e.g. B. a basicity above ^6o The suspension of the finely divided solid in 150 ¹ Vo are very suitable. Emulsifiers of the type the lubricating oil is then used in the lubricating grease and the partial esters are glycerol monooleate, monostearate works. The temperature at which this ver or monoricinoleate, diethylene glycol monolaureate, mixing is carried out is an important factor -monooleate or monostearate, sorbitol mono- or for the success of the process, and the best result -dioleate and the polycyethylene sorbitol esters of fat- , 65 would occur at temperatures between about space resin or naphthenic acids. temperature and 125 ° C.

The emulsifiers are usually used in quantities. This mixing preferably takes place at room

from 1 to 5 percent by weight, calculated on the temperature or slightly elevated temperature. In the

Temperatures between 80 and 120 ° C have also proven themselves in practice.

The lubricating greases used can contain any type of base lubricating oil, e.g. B. a mineral Lubricating oil or a synthetic lubricating oil such as a silicone fluid or a high boiling ester. That Thickening agent in the grease can be a soap, e.g. B. an alkali or alkaline earth soap of a fatty acid or oxy fatty acid, or an inorganic colloid such as silica or clay. The invention will used with particular advantage in lubricating greases which contain a mineral lubricating oil, the by an alkali soap, e.g. B. lithium or sodium stearate or oxystearate, is thickened.

The invention is explained in more detail by the following examples, in which the specified parts refer to weight.

example 1

20th

11 parts of sodium nitrite are dissolved in 19 parts of water, and the aqueous solution is 70 parts stirred a lubricating oil mixture, which by dissolving basic calcium naphthasulfonate and basic calcium alkylsalycilates (where the alkyl groups contain 14 to 18 carbon atoms) in a solvent refined mineral lubricating oil with a viscosity of 170 seconds according to Redwood I at 60 ° C. Each of the calcium compounds mentioned is found in applied in an amount equal to 0.04 percent by weight calcium calculated on the oil. The mixture is passed through a colloid mill at 60 ° C and the emulsion thus formed becomes complete through multiple recirculation through fine nozzles while heating the emulsion to 160 ° C drains. This treatment takes about 20 minutes and the product obtained is fine Suspension of sodium nitrite particles in the oil, the average particle size being smaller is than 1 micron.

46 parts of this suspension are mixed in the cold with 300 parts of a lubricating grease of the following composition: 11.5 percent by weight lithium soap from hydrogenated castor oil, 1 percent by weight phenyl-a-naphthylamine, 87.5 percent by weight solvent-refined mineral lubricating oil with a viscosity of 170 seconds Redwood I at 6O ⁰ C.

The grease so produced contains very fine particles of sodium nitrite with a particle size of to 2 microns, which are stably distributed throughout the whole mass. It has excellent anti-corrosion properties Properties.

Example 2

Example 1 is repeated with the modification that the suspension of the lubricating grease in one Mixer is incorporated at 120 °. The particle size of the dispersed sodium nitrite in the grease is larger than Example 1, namely 5 to 10 microns. However, this particle size is still sufficient for formation a grease with satisfactory properties.

Example 3

Example 1 is repeated with the modification that the emulsion is heated on a rotating machine Roller is dehydrated and that the suspension the grease at 120 ° C during cooling of the grease is incorporated in the final stage of its manufacture. The particle size of the Sodium nitrite particles in the resulting grease is 1 to 2 microns.

Claims (2)

PATENT CLAIMS: 1. A method for incorporating a water-soluble solid in a lubricating grease, characterized in that an aqueous solution of the solid with an oil-soluble emulsifier from the group of organic salts of a polyvalent metal or the organic acids derived partial esters of a polyhydric alcohol with a lubricating oil to form a Water-in-oil emulsion is emulsified, the emulsion formed is dehydrated by rapid evaporation and the suspension obtained is mixed with a lubricating grease at a temperature of at most 125 ° C. 2. The method according to claim 1, characterized in that the emulsifier is a mixture of one Petroleum sulfonates and a salt of an aromatic carboxylic acid or oxycarboxylic acid with is one or more alkyl substituents of at least 8 carbon atoms. Legacy Patents Considered:
German patents No. 1 091 685, 1121 258. © 309 687/288 9.63