DE623010C - Process for improving lubricating oils - Google Patents

Description

Lubricating oils, especially those that are to be used at low temperatures, e.g. Am Ice machines or in motors when the outside temperature is low, 'must have a low one Have pour point. The methods used up to now to lower the pour point of lubricating oils are mostly based on the fact that the oils are strongly cooled and the solidified fractions separated by filtration or centrifugation. This way of working is very expensive.

In addition to a low pour point, good lubricating oils must have a relatively low level have a slight difference in viscosities at 38 and 100 °, d. H. You need to in this respect are close to paraffinic lubricating oils, which are relatively have flat temperature viscosity curves, while asphalt-based and naphthenic Lubricating oils show greater dependence of viscosity on temperature. The oils should be as cheap as possible Have viscosity index determined by the definition of Dean and Davis, Chem. And ■ Met. Eng., Vol. 36, p. 618, represents a measure for the temperature dependence of the viscosity » It has now been found that excellent lubricating oils are obtained by using lubricating oils, e.g. B. asphalt-based or naphthemic Lubricating oils mixed with paraffin wax or other waxy substances to improve their temperature viscosity curve and also gives them a pour point depressant content to one to avoid undesired increase in the pour point.

20th Oil I. before after Oil II before after Oil III before after specific weight
² 5 pour point 0.887
-4 °
1.85
103.5 0.886
-23 ⁰
1.89
96 0.935
+ 4 °
1.92
102 0.916
-15 °
1.96
95 0.884
_. 7 °
1.76
IOO 0.881
-17 °
1.69
94 Viscosity in Engler ° at 100 ° C
Viscosity index

The table above shows the properties of several oils before and after Removal of the paraffin contained therein by cooling and pressing or centrifuging specified. '

It can be seen from this information that through

• The removal of the paraffin is indeed the point of contact is lowered, but that the temperature viscosity dependence in each case

ίο experiences a deterioration. ;

. As starting materials for the present process, for. B. paraffinic oils in question how they can be obtained from Pennsylvania and "midcontinent" crude oils; Even fractions obtained from low-quality crude oils can be produced with the addition of petrolatum or paraffin wax or slack paraffin be converted into valuable lubricating oils. The effect is particularly striking the addition of paraffin to oils that do not contain any from the outset, e.g. B. at asphalt-based and naphthenic oils. Furthermore, oils produced by pressure hydrogenation high-boiling carbonaceous substances have been obtained and often one have a high pour point, can be improved in this way.

Paraffin and pour point depressants can be added by first mixing these two substances and adding the mixture to the lubricating oil, or by adding the two additives to the lubricating oil separately one after the other. - Various substances can be considered as additives which lower the pour point. For example, the acids formed during the partial oxidation of paraffin and the like fulfill this purpose. To prepare pour point depressants of this type, the oxidation of the paraffin is expediently carried out at relatively low temperatures, e.g. B. at 150 to 16o ° or above, where «one optionally in the presence of catalysts, for. B. oil-soluble manganese or cobalt salts or cinnamic acid barium works. Small amounts of pour point depressants are sufficient to achieve the desired effect; • used, for example to 4 ° / ₀ of the total Paraffinoxydationsproduktes or 2% of the acids contained therein. Instead of these acids, their zinc or manganese salts can also be used in amounts of about 1% as pour point depressants.

Oxidized, extremely boiling petroleum distillates are further pour point depressants or called distillation residues, which are obtained by this at brings elevated temperatures into contact with an air stream and so partially Causes oxidation.

Very suitable pour point depressants are those according to Patent 556,309 by halogenation and condensation of high molecular weight, wholly or predominantly made of hard or soft 5g oils available from paraffinic hydrocarbons, which in themselves have lubricating oil properties own. The condensation of the hydrocarbons mentioned can not only be combined as in patent 556309 with aromatic hydrocarbons, but also with oxygenated aromatic Compounds such as naphthols, oxyanthracenes, substituted phenols and the like will. In the latter case, the pour point depressants can be oxygen, nitrogen and even contain small amounts of sulfur.

According to the invention 'can also be good lubricating greases z. B. lead oleate, aluminum oleate o. The like. Manufactured by adding point depressants.

Although it has already been suggested to use oils with a low level of natural or after paraffin content remaining after dewaxing by adding pour point depressants of the kind described. According to this, however, it could not be foreseen that "it would be possible to do so by adding paraffin and pour point depressants to produce excellent lubricating oils in which the valuable Viscosity properties can be made usable without impairment the other properties takes place.

95 example

A columbia lubricant is treated with sulfuric acid of D = 1.84 and filtered through clay. It then has the following properties:

Specific weight 0.910

Viscosity at 38 ° ..... 13.3 ° Engler

- ioo ° i> 74 ° -

Viscosity index 50

Pour point -18 °

Flash point 210 ⁰

8.5 parts of this oil are used 1 part petrolatum from the spec. Weight 0.872 and the Viscosity of 1.4 ° Engler at ioO °. That The resulting mixture has the following properties:

Specific weight 0.908

Viscosity at 38 ⁰ 12.2 ° Engler

- ioo ° i, 7 °

Viscosity index 60

Setting point + 15 °

So while the viscosity index is increased by units, the pour point is also increased ^{by 33 0 at the same time.} To this

Mix is ι part of a patent, 556 309 synthetic oil produced. The mixture now obtained has the following properties:

Specific weight 0.908

Viscosity at 38 ⁰ 12.2 ° Engler

- ioo ° i, 7 °

Viscosity index 60

Pour point .. below - 23 ⁰

The pour point of this oil is so low, despite the addition of about 10 ° / ₀ Petroleum, which improved the Temperaturviscositätskurve. You can also first mix the required amount of pour point depressant with the paraffin or petrolatum and then add this mixture to the oil. The invention does not include the simultaneous addition of pressure-hydrogenated cracking residues and paraffin to lubricating oils.

Claims (1)

Claim:
Process for improvement from Lubricating oils, characterized by the addition of paraffin and pour point depressants, the use of pressure hydrogenation products of cracking residues as pour point depressants is excluded.