DE1269118B - Process for improving the properties of high-performance lubricants used diester lubricating oils - Google Patents

Description

If one compares comparatively low molecular weight Di- Method to improve the properties

carboxylic acids with - preferably branched - pri- _of high-performance lubricants

Esterified alcohols are obtained, especially diester lubricating oils
for turbine engines, suitable lubricants. she
are characterized by resistance to the cold and 5

at high temperatures, excellent lubricating effect

and good viscosity-temperature behavior. However, all applicant-type esters have the disadvantage that they

Sealing materials swell strongly and even up- Technochemie G. m. B. H. Process engineering,

to solve. Despite the advantages mentioned, they are therefore io 6900 Heidelberg, Heiligenbergstr. 1 b

difficult to use.

With increasing length of the carbon chain of the Di- ^ _Erfmder

carboxylic acids reduce this disadvantageous behavior,. .

so that finally with a carbon number of 19 in ^{Dr. Herbert} Petrovicki, 6900 Heidelberg;

to the dicarboxylic acids, the esters are similar to mineral 15 Dr. Othmar Pauer, 5302 Beuel;

let use oil products. Such dicarboxylic acids Dr. Kurt Kirsch, 6901 Dossenheim

are z. B. available when acidic in the presence

Catalysts, such as sulfuric acid, under pressure

Oleic acid accumulates carbon oxide (cf. »Fuel Chemistry«, 2
Vol. 36, pp. 321 to 328 [1955]; »Annals of Chemistry«, 20

Vol. 618, pp. 251 to 266 [1958], and “Fette, Seifen, both means subject. Under »basic aluminum

Paints ", Vol. 59, pp. 493 to 498 [1957]. A "niumoxid" is to be understood as a product, its aqueous

Technical mixture of di-suspension obtained in this way has a pH of about 10. It

carboxylic acids with an average of 19 carbon- is obtained by heating technical, with

atoms shows the following 25 alkali metal precipitated aluminum hydroxide to 250 to after the distillation

Properties or key figures 400 ⁰ C (Ullmann's encyclopedia of technical

Viscosity ¹ ^ ' ⁴ · Edition, Vol. II, 1, p. 107, 1961).

at 50 ° C 842 8 cSt - ^ ^as inventive method for improvement

at 98 ° C 6l'l cSt ^ ^er properties of as high-performance lubricants

Viscosity index 76 ³ ° serving diester lubricating oils, which by esterification

Contained pour point -15 5 ⁰ C ^by an average of 19 carbon atoms

Acid number .................... 335 'tendency, due to the addition of carbon oxide to oleic acid

available dicarboxylic acid mixtures with at least

By esterifying this dicarboxylic acid mixture containing 6 carbon atoms, monovalent

are produced with isononyl alcohol from the oxo synthesis in counter-branched alcohols, is thereby

wart of sulfuric acid as a catalyst is obtained characterized in that it is treated with

after the distillation at 250 ° C / 0.55 mm a mixed urea and / or with activated carbon and »ba

ester with the following key figures sic aluminum oxide «.

viscosity

at 50 ⁰ C 28.6 cSt ⁴ ° B eis ρ ie 1 1

at 98 ⁰ C 6.67cSt ^ _-1 _ __ _J,. ,

Viscosity index. 108 2000 parts by weight of heptadecanedicarboxylic acid-dnso-

Pour point -61 5 ° C nonyl esters become methylene chloride in 1400 parts by volume

Acid number . . . '. 6Ί dissolved and heated under reflux. Then one lets

45 a hot solution of 1000 parts with stirring

This ester shows in comparison to others, e.g. B. urea in 1400 parts by volume of methylene chloride so zuaus Sebacic acid obtained, an unsatisfactory flow that the mixture always refluxes. Viscosity-temperature behavior. It is then slowly carried out for several hours. It has now been found that such esters can be cooled to room temperature, the mixture of It can be improved significantly if it is treated with 50 solid parts by centrifuging or filtering with urea or with a mixture of freit and the residue twice with 200 space activated carbon each time and "basic alumina" or partially washed methylene chloride. The filtrate will

1

up to a bottom temperature of 8O ⁰ C evaporated, mixed with 3000 parts by volume of water and acidified (pH = 3 to 5). After separation of the aqueous phase and neutral washing with water, the organic phase is removed by azeotropic distillation with benzene as an entrainer 5 from the rest of the water and distilled to a pot temperature of 130 ⁰ C at 1mm. After this treatment, the ester shows the following key figures

viscosity

at 50 ^° C 28.8 cSt

at 98 ° C 7.64 cSt

Viscosity Index 132

Pour point -58 ⁰ C

Acid number 6

The viscosity-temperature behavior is therefore essential improved.

If you use activated carbon and "basic aluminum oxide" instead of urea, you get one Improvement in both viscosity index and acidity and color, like that the following example shows.

Example2

To 1000 parts heptadecanedicarboxylic-diisononyl esters are added 20 parts of carbon and 20 parts "basic alumina" and the mixture heated with stirring for about 2 hours at 6O ⁰ C. After

118

Filtering off the solid fractions, the ester shows the following Key figures

viscosity

at 50 ° C 27.5 cSt

at 98 ° C 7.34 cSt

Viscosity Index 131

Pour point -61 ⁰ C

Acid number 2.6

The treatment can also be carried out by percolating a column filled with the agents mentioned. You can also use the two methods of treatment, i.e. the one with urea and the one with the mixture of activated carbon and "basic aluminum oxide".

Claims (1)

Claim: Process for improving the properties of diester lubricating oils used as high-performance lubricants, those containing an average of 19 carbon atoms by esterification, by the addition of carbon oxide to oleic acid available dicarboxylic acid mixtures containing at least 6 carbon atoms monovalent branched alcohols are produced, characterized in that they are a treatment with urea and / or with activated carbon and "basic aluminum oxide". 809 557/502 5.68 © Biradesdruekerei Berlin