DE1149844B - Mineral lubricating oil - Google Patents

Description

GERMAN

PATENT OFFICE

S 68894 IVc / 23c

REGISTRATION DATE: JUNE 10, 1960

NOTICE
THE REGISTRATION
AND ISSUE OF
EDITORIAL: JUNE 6, 1963

Mineral lubricating oil

The invention relates to mineral lubricating oils which contain N-substituted glycine compounds.

Rusting of ferrous surfaces is a common phenomenon in the field of Special attention must be paid to lubrication and B. a serious problem in the case of steam turbine lubrication, especially when new systems are initially operated. Rust formation occurs primarily in those places where the clear width between bearing surfaces, as with regulator mechanisms, is very small. It is usually caused by water, which enters the oil supply through condensation, for example, and becomes in the oil through the circulation system entrained, whereby it comes into contact with the ferrous surfaces. It represents this one poses a significant risk to the service life of the turbine.

Many substances have been proposed as additives in order to impart anti-rust properties to lubricating oils To give. To prevent rust in the presence of seawater, such as in marine turbine lubrication, Most of the compounds used were materials containing two or more carboxylic acid groups (-COOH). Monocarboxylic acids have generally proven to be non-existent in ship service proven effective.

Applicant:

Socony Mobil Oil Company,
Inc., New York, NY (V. St. A.)

Representative: Dr. E. Wiegand, Munich 15,

Nussbaumstrasse 10, and Dipl.-Ing. W. Niemann,

Hamburg 1, patent attorneys

Claimed priority:

V. St. v. America June 10, 1959

(No. 819 233 and No. 819 234)

Harry John Andress Jr., Pitman, NJ, and
Paul Yoke Chan Gee, Woodbury, NJ (V. St. A.), has been named as an inventor

It is known to use N-substituted glycines of the formulas below in mineral lubricating oils

Il

R-CH-C-OH CH ₂ -C -NHR

Il ο

Il

RC-NHCH ₂ COOH

O CH ₂ COOH

Il /

RC-N

CH ₂ COOH

O CH ₂ CONH ₂

RC-N

CH ₂ COOH

to use.

However, the use of these additional compounds does not provide a solution to the invention lying task, the creation of mineral lubricating oils, especially turbine oils, which also have good anti-rust properties in the presence of seawater. Mineral lubricating oils, which the well-known Containing additives do not meet the emulsion tests. It also leads to the well-known Mineral lubricating oils intended use of amines to solubilize the additional compounds for the formation of unwanted green precipitates in the event of long-term oxidation residues.

It has now been found that mineral lubricating oils can be given effective anti-rust properties in the presence of seawater by adding certain glycine compounds.
The mineral lubricating oil according to the invention is

309 599/283

by the content of a small amount of N-sub substituted glycines of the general formula

HO

I Il

X - C - C - NHCH ₂ COOH

I - ι

Xi-C-C-Y
O

or

Il

R-CH-C

N-CH ₂ COOH

H ₂ C-

characterized, where X and Xi are either H or an alkenyl radical having 8 to 35 carbon atoms, with the proviso that only one of the symbols X or Xi is hydrogen, and Y is either OH or NHR ', where R' is a tert., in the α-position to the nitrogen atom is alkyl radical with 6 to 30 carbon atoms which is only substituted with methyl groups, R represents an alkenyl radical with 8 to 35 carbon atoms and the compounds I in the case of Y = OH and II can be present _{as salts with amines RTSfH 2.}

The additional compounds provided according to the invention can be obtained by reacting glycine (aminoacetic acid) and an alkenyl succinic anhydride or an alkenyl succinic acid. This production is not the subject of the present invention.

When equimolar amounts of an alkenyl succinic anhydride and glycine are condensed without forming water of condensation, an amic acid is formed. The condensation easily takes place in the range of ambient temperatures or higher temperatures. The reaction is an amide formation which is brought about by the known addition of the anhydride group to an amino group. This addition takes place at any temperature, but temperatures between approximately 90 and 120 ^° C. are preferred. The reaction time depends on the amount charged and the reaction temperature selected. Usually the addition of the acid anhydride is nearly complete in a few minutes. In order to ensure that the reaction is complete, the heating is preferably continued for a few hours, optionally 10 hours. In general, the reaction time varies between a few minutes and about 10 hours. If desired, non-polar solvents such as benzene, toluene, kerosene or xylene can be used to improve the flowability.

Although the anhydride is preferred, the compounds used according to the invention can also be prepared from the corresponding alkenylsuccinic acid. In this case, the condensation with the amino compound is accompanied by the formation of one mole of water per mole of amine. In this case, the reaction is carried out at temperatures between about 130 and 200 ^° C., although the reaction can also be carried out at temperatures above or below this range. The reaction continues until 1 mole of water per mole of alkenyl succinic acid is evolved, which usually takes about 6 to 10 hours. To facilitate removal of the water and to achieve a more complete reaction in accordance with Le Chatelier's principle, a hydrocarbon solvent which forms an azeotropic mixture with water can be added to the reaction mixture. Heating is continued until the removal of the water by azeotropic distillation is essentially complete. Examples of suitable solvents which form azeotropes are benzene, toluene and xylene.

The salt of the amic acid can easily be obtained by heating the amic acid and a primary tertiary Alkylamine can be produced in equimolar proportions.

The amide of the amic acid can be prepared by any of the conventional amide-forming reactions will. It is easiest by reacting the amic acid and the tertiary alkylamine in equimolar amounts Quantities and with the removal of one mole of water of condensation. The applied Reaction conditions correspond to those above for the conversion of alkenylsuccinic acid conditions indicated with the amine compound reactant.

If equimolar amounts of an alkenylsuccinic anhydride or an alkenylsuccinic acid and glycine are reacted with elimination of condensation water, an N-carboxymethylalkenylsuccinimide is formed. In the case of the anhydride, 1 mol of water is formed per mol of reaction component, in the case of the acid 2 mol of water are formed. Accordingly, the condensation is carried out at temperatures between approximately 150 and 250 ^° C., preferably between approximately 175 and 200 ^° C. The reaction time depends on the reaction temperature used. The reaction continues until the required amount of condensation water is developed. Generally the time will vary between 2 and 6 hours. Shorter reaction times result if the water is removed by azeotropic distillation. Suitable liquids which form azeotropes with water are non-polar solvents such as benzene, toluene or xylene.

The alkenyl radical of succinic acid or succinic anhydride contains 8 to 35 carbon atoms, preferably between 10 and 14 carbon atoms. Examples of the leftovers are:

Octenyl, diisobutenyl, 2-methylheptenyl, 4-ethylhexenyl, Nonenyl, decenyl, undecenyl, dodecenyl, triisobutenyl, tetrapropenyl, tetradecenyl, hexadecenyl, 11-tricosenyl and 17-pentatriacontenyl.

The amine salts of the N-carboxymethyl alkenyl succinimides can easily be prepared by heating the succinimides with an equimolar amount of a tertiary alkyl primary amine. The addition takes place easily without giving off water, but it is facilitated ^{by heating to temperatures between about 50 and 100 ° C.} The amines which are suitable for forming the salts are the primary tertiary alkyl monoamines in which a tertiary carbon atom is bonded to the nitrogen atom and which between

contain about 6 and 30 carbon atoms in the tertiary alkyl radical, and mixtures thereof. These amines all contain the end group N-carboxymethylalkenyl-succinimide
O

(g) R -CH-C

- CH ₂ -C-NH ₂

CH ₃

Examples of the amines are primary tertiary hexyl, octyl, nonyl, decyl, dodecyl, tetradecyl, octadecyl, Eicosyl-, docosyl-, tetracosyl- and tricontylamine.

From the above it can be seen that the compounds used according to the invention represented by the following specific formulas included in general formulas I and II can be:

N-CH ₂ COOH

H ₂ C-

Amic acids

(a) R -CH-COOH

H ₂ CC-NHCH ₂ COOH O

Amic acids O

I!

(b) R-CH-C-NHCH ₂ COOH

H ₂ C-COOH

Amic acid salts

(c) R -CH-COOH

H ₂ CC-NHCH ₂ COOH • (R ⁷ NH ₂ ) * O

Amic acid salts O

(d) R - CH - C - NHCH ₂ COOH (RNH ₂ ) *

H ₂ C-COOH

Amidamides O

(e) R -CH- C-NHR '

H ₂ C - C - NHCH ₂ COOH O

Amidamides O

Il

(f) R-CH-C-NHCH ₂ COOH

H ₂ CC-NHR '

Il ο N-carboxymethylalkenyl succinimide salts
O

(Ii) R -CH-C

H ₂ C-

N-CH ₂ COOH-R ⁷ NH ₂

in which R is an alkenyl group with 8 to 35 carbon atoms, preferably with 10 and 14 carbon atoms, R 'the tertiary alkyl radical which contains 6 to 30 carbon atoms, and χ represents an integer of 1 or 2.

The compounds obtained from glycine cause mineral lubricating oils, especially highly refined ones Mineral lubricating oils, such as steam turbine oils, are given anti-rust properties. The amount such a compound, which is added to the lubricating oil, varies between about 0.001 and 10.0 percent by weight of the oil. Amounts between about 0.05 and 1.0 percent by weight are preferred used. The lubricating oil can also contain conventional additives such as antioxidants, pour point depressants, V.I. improvers and extreme pressure agents contain.

The N-substituted glycines can be prepared, for example, by the following procedures:

1. A mixture of 75 g (1, OMoI) glycine and 300 g (1 mol) of tetrapropenylsuccinic anhydride is slowly added at about 110 to 115 ° C. with stirring heated. The reaction mixture is allowed to react for about 3 hours to ensure complete reaction stirred for a long time at 110 to 115 ° C.

2. A mixture of 37.5 g (0.5 mol) of glycine and 150 g (0.5 mol) of tetrapropenylsuccinic anhydride is slowly heated to about 110 to 115 ° C. with stirring. The reaction mixture is stirred at 110 to 115 ° C for about 3 hours. The mixture is ^{cooled to about 50 °} C., and 100 g (0.5 mol) of amine A are added. The mixture is stirred for about 3 hours at 100 ° C. to ensure complete reaction.

3. A mixture of 37.5 g (0.5 mol) of glycine and 150 g (0.5 mol) of tetrapropenylsuccinic anhydride is slowly heated ^{to about 110 to 115 ° C. with stirring.} The reaction mixture is stirred at 110 to 115 ° C for about 3 hours. The mixture is cooled to 50 ° C. and 200 g (1.0 mol) of amine A are added. The mixture is stirred for about 3 hours at 110 ^° C. in order to ensure complete conversion.

4. A mixture of 37.5 g (0.5 mole) glycine and 150 g (0.5 mole) tetrapropenyl succinic anhydride slowly with stirring to about 100 to 115 ° C

heated. The reaction mixture is stirred at 100 to 115 ° C for about 3 hours. The product that the. Amic acid corresponds to procedure 1, is ^{cooled to about 50 0} C, and there are 100 g (0.5 mol). Amine A added. The resulting mixture is then heated slowly to a final temperature of 200 ⁰ C. About 9 g (about 0.5 mol) of water of condensation are evolved during this reaction step to form the amine-A-amide of the product according to Procedure 1.

5. A mixture of 37.5 g (0.5 mol) of glycine and 150 g (0.5 mol) of tetrapropenylsuccinic anhydride is slowly ^{heated to a temperature of about 200 °} C. over a period of about 12 hours. 9 g (0.5 mol) of water are evolved during the course of the reaction.

6. A mixture of 37.5 g (0.5 mol) of glycine and 150 g (0.5 mol) of tetrapropenylsuccinic anhydride is slowly ^{heated to a temperature of about 200 °} C. over the course of 12 hours. The mixture is cooled to about 75 ° C and 100 g (0.5 mol) of amine A are added. The mixture is stirred for about 2 hours at 100 ° C. to ensure complete reaction.

example

Six mineral oil mixtures are produced. Each mixture contains a small proportion of one of the additives obtained according to procedures 1 to 6. Two base oils were used. Oil X is a substantially solvent-refined mineral lubricating oil having a density of 0.8708 g / cm ³ a viscosity of 150 SUS at 38 ° C. Oil Y is a highly solvent refined Mid-Continent oil having a density of 0.8816 g / cm ³ and a viscosity of 415 SUS at 38 ° C. Both are typical steam turbine lubricating oils. These blends are subjected to ASTM Rust Test D 665-44 T using synthetic seawater. The composition of each mixture and the test results are shown in the table.

The salt-forming amine, which is used in the special production methods, is a mixture * pure amines. "Amine Α" is a mixture of amines NH2R ', where R' is a directly attached to the nitrogen atom bonded tertiary butyl group and a total of 12 to 15 carbon atoms per amine and contains an average of 12 carbon atoms. This mixture contains about 85 percent by weight tertiary Dodecylamine, about 10 percent by weight tertiary pentadecylamine and relatively small amounts, d. H. less than about 6 weight percent, of amines having fewer than 12 or more than 15 carbon atoms.

The test method used to determine the rust properties of lubricating oil blends was ASTM Test D 665-44 T for determining the rust preventive properties of steam turbine oils in the presence of water using synthetic seawater. The synthetic sea water contained 25 g sodium chloride, 11 g magnesium chloride hexahydrate, 4 g sodium sulfate and 1.2 g calcium chloride per liter. In this test a polished steel rod of cylindrical in 300 cm ³ is immersed to be examined of the oil for 30 minutes at 6O ⁰ C. 30 cm ^{3 of} synthetic sea water are added and the mixture becomes

40

55

60 stirred at 100 revolutions per minute. After hours, the steel rod is removed and the part of the rod that protruded into the oil is examined. When performing this test, the test sample must be completely rust-free.

Additive, Conc Base oil ASTM rust test obtain
after tration
Weight Way of working percent X failed no X passed 1 0.05 X passed 4th 0.05 Y failed - no Y passed 2 0.05 Y passed 3 0.05 X failed - no X passed 5 0.10 Y passed 6th 0.05

It can be seen that the compounds listed herein are effective in the presence of lubricating oils to impart anti-rust properties to seawater. Therefore, these mineral oil compositions are for example in the lubrication of marine turbines, highly effective.

Claims (4)

PATENT CLAIMS: 1. Mineral lubricating oil, characterized by the Content of a small amount of N-substituted glycines of the general formula HO I Il X - C - C - NHCH2COOH I ι Xi-C-C-Y
HO or HO I Il R — C —C N -CH2COOH H ₂ -CC Il ο where X and Xi are either H or an alkenyl radical having 8 to 35 carbon atoms, with the proviso that in each case only one of the symbols X or Xi represents hydrogen, and Y either OH or NHR ', where R' a tertiary alkyl radical which is only substituted with methyl groups in the α-position to the nitrogen atom having 6 to 30 carbon atoms, R represents an alkenyl radical having 8 to 35 carbon atoms and the compounds I in the case of Y = OH and II are present as salts with amines R'NH2 can, in which R 'has the meaning given above. 2. Mineral lubricating oil according to claim 1, characterized in that it is between 0.001 and 10 percent by weight, preferably 0.05 to 1 Ge percent by weight, based on the lubricating oil, which contains N-substituted glycines. 3. Mineral lubricating oil according to claim 1 or 2, characterized in that the N-substituted Glycine as amic acid, obtained from tetrapropenyl succinic anhydride and glycine, the amino mono- or di-salt or mono-amide of which is present, the salt- or amide-forming amine is a mixture of alkylamines NEfeR ', in where R 'is a tertiary alkyl radical having 12 and 15 carbon atoms with an average of about 12 carbon atoms is. 10 4. Lubricating oil according to claim 1 or 2, characterized in that the N-substituted glycine N-Carboxymethyltetrapropenylsuccinimide or its amine salt, the salt-forming Amine represents a mixture of alkylamines NH2R ', in which R' is a tertiary alkyl radical with 12 and 15 carbon atoms on average with about 12 carbon atoms. Considered publications:
U.S. Patent Nos. 2,604,451, 2,790,778, 790,779, 2,790,780.