SU896060A1 - Petroleum oil thickener - Google Patents

Description

(54) CONSTANT OIL OILS

one

The invention relates to greases and lubricants, which are a suspension of highly dispersed graphite, which gives the compositions a certain viscosity, in oils used in mechanical engineering, metal / turkey, radio engineering, etc.

Dry colloid-graphite preparations C-1 and C-2 are used as thickeners for suckers with others. .

The colloid-graphite preparation C-1; it is a finely dispersed low-ash dry gra4ite with an hour size, particles of 2-4 microns. This C-1 preparation is semi-repeated by grinding the artificial or natural graphites: colloid mills in the presence of surfactants. The process of obtaining the colloidal-graphite preparation C-1 is a multistage one, it is very complicated. It is carried out on bulky and energy-intensive equipment.

The purpose of the invention is to develop petroleum oils with high zagu-

properties, the production technology of which is an established process.

To achieve this goal, it is proposed to use expanded graphite as a thickener for petroleum oils.

Expanded graphite is used as a filler in a mixture with synthetic resins for the manufacture of extruded structural materials of flexible graphite tape by rolling 2,

Expanded graphite (along the crystal axis C) is obtained as follows.

Natural or artificial graphite is treated with stirring with a 109% solution of sodium, potassium bichromate in concentrated sulfuric acid (1.84 g / cm®) for 30–60 minutes. After processing, the graphite is separated from the liquid phase by filtration or centrifugation and washed with distilled water.

until neutral and dried at 1015-120 ° C. Dried graphite will be rapidly heated at 600-1000 ° C.

As a result of such processing, graphite acquires a petal structure. The volume density is 0.03-0.005 g / cm. Bulk density is reduced by a factor of 100 or more, and specific; the surface increases ao 200 m2 / g.

The described technology makes it possible to obtain expanded graphite with a given specific surface and with a given particle size, to avoid the complex and non-economic process of repeatedly breaking up artificial or natural graphite in colloid mills. In addition, the process of obtaining a grapitic preparation is simplified, the consumption of thickener for the preparation of a lubricant with desired properties is significantly reduced.

The thickening ability of expanded graphite compared to the known graphite thickener C-1 is judged by the change in shear strength

Indicators

Shear strength at 20 ° С, gf / cm

Evaporation according to GOST 9566-6О at 15О ° С,%

for 1 h

in 31 hours

Thermal-oxidative stability at 2OO ° C:

hardening time, h

mass loss,%

Lubricating properties on the four-ball friction machine according to GOST 949О-75:

As can be seen from the table, expanded graphite has a better thickening ability than graphite C-1. With a content of 15% expanded graphite, the lubricant based on the oil MK-22 has a shear strength of 8.2 gf / cm, while the shear strength is

and change the oil number. The test results are presented in the table.

The oil number is determined in accordance with GOST 7885-68, 0.5 g of expanded graphite or C-1 graphite, weighed with an accuracy of 0.0001 g, is placed in a porcelain dish and dibutyl phthalate is added dropwise from a microburette. After each drop is added, the mixture of graphite and dibutyl phthalate is carefully ground with a spatula until the oily traces of dibutyl phthalate disappear from the cup walls. Dibutyl phthalate is stopped at the collection time of the whole graphite on the paddle. The resulting cake should not break or split with gentle pressure.

The oil number (X) in ml / lUO g is calculated using the formula .V,

where h / is the volume of adsorbed dibutyl phthalate in ml,

The table shows the properties of lubricants with the use of expanded graphite and known C-1.

Graphite C-1

Expanded graphite 35 wt. % 15 wt.%

8.2

1.2

Missing

Oh 55 4.3

5.8,

586

556 18.3 20.5

When the content of 35% graphite C-1 1,2 rc / cMi

The oily number characterizing the amount of non-volatile liquid absorbed by the surface of solid particles for expanded graphite is

750 ml / 100 g, and for C-1 - only 115 ML / 10O g.

The thickening ability of the extended graph is due to the special crust of particles. The particles of graphite as a result of chemical treatment and subsequent calcining acquire greater porosity due to the separation of the crystallites of the initial graphite into separate packets of basal planes. The bulk density of expanded graphite decreases 1OO more times and the specific surface area increases.

20-50 times reduced. Therefore, when mixing liquids with expanded graphite, the fluid enters the interplanar bone space and is held in

non-absorptive forces. In addition, the specific number of particles of expanded graphite increases by an order of magnitude compared to the initial one, which also increases the liquid adsorption rate per unit weight of this material. At the same time, the thickening ability of graphites, including C-1, is due to the adsorption of the liquid only on the outer surface of the particles.

Thus, the use of expanded graphite as a thickener for petroleum oils instead of the graphite preparation C-1 has a lot of advantages. Preparing a dry graphite preparation C-1 is a complicated and expensive process, while obtaining an expanded grant does not require energy-intensive mechanical processing. The specific surface and particle size of the expanded graphite, and with it the thickening properties can be varied over a wide range of values by changing the haul-off conditions.

The use of expanded graphite as compared with С-1 allows to significantly reduce (more than 3 times) the consumption of thickener during the delivery of lubricants.

Claims (2)

Invention Formula The use of expanded graphite as a thickener for petroleum oils. Sources of information taken into account in the examination , I. GOST 5.1386-73, 2. US Patent No. 34О406 1, cl. 161-125, pub. 1968.