DE1125577B - Lubricating oil - Google Patents

Description

The invention relates to lubricating oils which contain an additive which gives them improved anti-rust, imparts emulsion-preventing, wear-reducing properties and high pressure properties.

For certain purposes, e.g. For example, for lubricating turbines, oils must have special properties as the presence of water increases the risk of rusting the metal parts brings. The additives to be used according to the invention are extremely valuable for such cases because they prevent rust and emulsification between oil and water.

The lubricating oil according to the invention is characterized in that it is a carboxylic acid as an additive general structural formula

R-O-C-S CH, COOH

Applicant:

Esso Standard Societe Anonyme
Frangaise, Paris

Representative: E. Maemecke, Berlin-Lichterfelde West,

and Dr. W. Kühl, Hamburg 36, Esplanade 36 a,

Patent attorneys

Claimed priority:
France of 7 July 1958 (No. 769 675)

contains, in which R is an alkyl radical having 4 to 20 carbon atoms.

These additives can be produced in a simple, known manner by one monohydric aliphatic alcohol corresponding to the radical R and having 4 to 20 carbon atoms in the molecule with carbon disulfide and a metal hydroxide to a xanthate and this then with the salt a haloacetic acid. The reaction product eventually becomes the free acid of the above Formula with HiKe of a strong acid such as hydrochloric acid, set free, purified and isolated.

Patent protection is not claimed here for the manufacture of the additives.

It is known to use oil-soluble disulfides or polysulfides of xanthates together with organic nitro compounds to be used as lubricating oil additives to improve high pressure lubricity.

It is also known to use certain polyalkylene glycol xanthogenic acid derivatives of very intricate molecular structure as a lubricant on its own or as an additive to mineral oils or to polyalkylene glycols to be used to increase the high pressure lubrication capacity.

The oil additives to be used according to the invention give the lubricating oils primarily anti-rust properties for the metal parts with which they come into contact. They also offer the advantage of not forming an emulsion, so that emulsification between the oil and the water is prevented. In addition, these additives give the greases and oils to which Robert de Dryver, Notre-Dame-de-Gravenchon,
Seine-Maritime, Jean-Baptiste Signouret,

Billiere-Pau, Basses-Pyrenees,
and Robert Tirtiaux, Notre-Dame-de-Gravenchon,

Seine-Maritime (France),
have been named as inventors

are added, extreme pressure properties and wear-reducing properties.

The amount of additive to be added to the lubricant base depends on the intended use. If the rust protection is all that matters, an additive between 0.01 and 0.5 is sufficient, preferably between 0.03 and 0.1 percent by weight, based on the total amount of lubricant. Should High-pressure properties are imparted to lubricating greases or lubricating oils, it is preferred to use 1 to 10 percent by weight, based on the total amount of lubricant.

Mineral or synthetic oils can be used as the oil base for the lubricants; preferably paraffinic oils are used. The lubricants according to the invention can also other additives, such as pour point depressants, viscosity index improvers, oxidation retardants and dyes, contain.

example 1

The additive A is made in a manner known _{per se by reacting 63.2 g of C 10} -oxoalcohol with 18 g

209 519/416

Carbon disulfide and 8 g of soda, further conversion of the 48 g of sodium xanthate obtained in this way with 21.8 g of sodium monochloroacetate, acidifying the reaction product with dilute hydrochloric acid and Purification of the resulting carboxylic acid produced.

Corrosion protection tests are carried out according to ASTM test standard D-665-49T with the aid of a paraffin oil (Viscosity index = 107; viscosity = 86.6 cSt at 37.7 ° C). These exams have the following results:

additive Weight percent Results None 0 Wave on by distilled water or sea water 2,6-di-tert-butyl-4-methylphenol
Addition A 0.4
0.05
0.4
0.05 eaten
Wave on by distilled water or sea water
eaten
No corrosion
> No corrosion 2,6-Ditert.butyl-4-methylphenol ...
and
Addition A

Example 2

With the addition of example 1, oxidation tests according to the modified "Steager-Life-Test" carried out.

The lubricating oil mixture (200 ecm) is placed in a drying chamber with a rotating base (4 to 5 rpm) at 110 + 0.5 ° C while passing through a stream of purified air at one speed from 47 to 541 / hour in the presence of polished electrolytic copper plates (40-70-0.1 mm) oxidized, the copper plates being replaced every 72 hours will.

After 380 hours, the acid number and the NPA color are measured and compared with the corresponding Values for the same parts before oxidation compared.

With the oil base used in Example 1, these tests lead to the following results:

additive Weight
percent Before the test
Acid number | NPA color 2+
2+
2+ After 380 hours
at HO ⁰ C
Acid number [NPA color black
5V ₂
5+ None 0.4
0.4
0.05 0.04
0.04
0.04 3.5
0.11
0.10 2,6-di-tert-butyl-4-methylphenol
2,6-di-tert-butyl-4-methylphenol
and
Addition A

These results show that the addition of product A to one of the antioxidants (2,6-di-tert-butyl - 4 - methylphenol) containing lubricating oil has no adverse effect on its resistance to oxidation.

Example 3

The demulsification tests are performed according to the set of American federal standards (WL 79Ie) described method 32 015 of 21.5.53 carried out which, apart from some Details that correspond to the French test standard "P 1571 ex 165 ter" (of the French fleet).

These tests are performed at 82 ° C with 40 ml of oil and 40 ml of distilled water or sea water under run under the following conditions:

Speed of rotation

of the plate 1500 rpm

Time to emulsify .. 5 minutes

A paraffinic oil of one serves as the oil base Viscosity index of 105 and a viscosity of 86.6 cSt at 37.8 ° C.

The results are compiled in the following table.

additive

Weight percent

Decanting time

Minutes of distilled water
aqueous

Phase ecm oil phase

emulsion

aqueous

phase

ecm

Sea water oil phase

Emulsion ecm

None |

2,6-di-tert-butyl-4-methylphenol

2,6-di-tert-butyl-4-methyl-

phenol

Addition A

0.4

0.4
0.05

10
20th

10
20th

10
20th

43 40

42
41

42
41

0 0

0 0

0 0

37 38

38
39

37
39

43 42

42 41

43 41

0 0

0 0

0 0

Example 4

If a lubricating oil additive is prepared according to Example 1, but amyl alcohol is used as the starting material instead of the C ₁₀ -oxo alcohol, a carboxylic acid is obtained which is referred to below as "Additive B" and has an acid number of 190 and a sulfur content of 23 percent by weight.

With a paraffinic lubricating oil with a viscosity index of 113 and a viscosity of 32 cSt at 37.8 ° C, which contains this additive, high-pressure tests are carried out in a four-ball device (see pp. 446 to 448, Vol. III, 2nd World Petroleum Congress, 1936, as well as SAE-Journal, Vol. 44 ND 5, p. 196, May 1939).

These tests have the following results:

Welding load, kg

Base oil without additives 110 Base oil + 2% additive B 250

Claims (3)

PATENT CLAIMS: 1. Lubricating oil, characterized in that it as an additive a carboxylic acid of the general structural formula R —O —C- CH ₂ -COOH contains, in which R is an alkyl radical having 4 to 20 carbon atoms. 2. Lubricating oil according to claim 1, characterized in that there is the addition in amounts of 0.01 to 10 percent by weight, based on the total amount. 3. Lubricating oil according to claim 1 and 2, characterized in that the lubricating oil base is a Mineral oil or a synthetic oil. _ Considered publications:
German patent specifications No. 925 192, 923 318. © 209 519/416 3.