AT215050B - Lubricating oil composition - Google Patents

Description

  

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    Lube oil position
In the two-stroke spark ignition internal combustion engines, fuel, generally gasoline containing lubricating oil, is introduced into the combustion chamber through the carburetor. Part of the oil separates out of this mixture in the engine and takes care of the lubrication, the remaining part of the oil gradually burns completely or incompletely and goes off with the exhaust gases.



   Studies have shown that the individual types of lubricating oil have a detrimental effect on the combustion properties of the fuel to different degrees. The combustion properties of the fuel are most impaired by paraffinic oils, which is reflected in the lowering of the octane number. This effect of reducing the octane number can be perceived in the straight as well as in the crack and ethyl benzines. This effect is pronounced to a lesser extent in the case of the mixed oils based on paraffin and naphthene and to a lesser extent in the case of the naphthenic oils.



   It has been found that the harmful effect of the lubricating oils on the combustion properties of the fuel can be reduced or completely eliminated if the lubricating oil composition contains 80-95% naphthenic lubricating oil and 20-5% monomethyl or ethyl derivatives of aniline.



   In this description, a naphthenic lubricating oil is understood to mean a lubricating oil which, in its chemical composition, has 40-60% by weight of naphthenic aromatic ring content.



   The effect of the lubricating oil composition can be further improved by adding ash-free and oil-soluble additives that improve the properties of the lubricating oil. These additives can be used in an amount of 1.5 to 6.8%, advantageously in an amount of about 3 to 4%. The lubricant composition advantageously jointly contains the following customary ash-free additives: a) sulfuric or sulfuric acid increasing the oxidation stability. sulfur- and phosphorus-containing organic substances, such as. B. thiophosphoric acid ester, or the reaction product of phosphorus pentasulfide and turpentine; b) Oil-soluble, ash-free detergents which have a cleaning effect on the surface of the internal combustion engine. For this purpose, a nitrogen-containing copolymer, e.g.

   Use, e.g., a copolymer of diethylaminoethyl methacrylate and lauryl methacrylate ester; c) an ash-free, rust-preventing additive, advantageously e.g. B. unsaturated oxy fatty acids or their esters; d) wear-reducing, ash-free substances, advantageously chlorine-containing organic compounds that do not cause corrosion, e.g. B. monochlomaphthalene, and furthermore e) substances preventing lead deposits, advantageously organic phosphates or phosphites, eg. B. tributyl phosphite, tricresyl phosphite.



   The fact that all additives are ash-free means that deposits in the internal combustion engine can be reduced to a minimum. For the two-stroke internal combustion engines with spark ignition, ash-containing substances were generally used as additives, which were only used for special lubrication purposes and which generally caused harmful deposits in the internal combustion engine.



   The lubricating oil composition according to the invention is added to the fuels, especially gasoline, of the two-stroke combustion engines with spark ignition in an amount of 1 to 10% by weight.

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     At pie I 1: 840 g of naphthenic lubricating oil with the following data:
Naphthene aromatic ring content 46% by weight
Viscosity at 1000C (Centistoke) 15.8 cSt
Viscosity-density constant 0.8677
Flash point according to Marcusson 2460C
125 grams of monomethylaniline
35 g of ash-free additives with the following composition:
10.0 g of dioctyldithiophosphoric acid ester
3.0 g copolymer of diethylaminoethyl methacrylate and lauryl methacrylate
1.0 g of isopropyl ricin oleate
19.0 grams of monochloronaphthalene
2.0 g tributyl phosphate
Example 2:

   845g naphthenic lubricating oil with the following data:
Naphthene aromatic ring content 48% by weight
Viscosity at 1000C 15.96 cSt
Viscosity-density constant 0.8708
Flash point according to Marcusson 2410C
100 g monoethylaniline
5 g ash-free additional mixture:
18 g sec. Octyl-isopropyl-dithiophosphoric acid ester
12 g copolymer of diethylaminoethyl methacrylate and cetyl methacrylate
20 g monochloronaphthalene
3 g triphenyl phosphite.



   Comparative tests were carried out to determine the extent to which the lubricating oil compositions containing nitrogen-containing aromatic compounds offset the octane number-lowering effect of the various lubricating oils. It was also investigated to what extent the ashless ingredients that improve the lubricating properties influence the combustion properties of the fuel, namely the octane number. The experimental data are illustrated in the table below.



   In the experiments, naphthenic lubricating oil according to Example 1 and paraffinic lubricating oil were used, to which equal amounts of ashless additives were added in one series of experiments, monomethylaniline in a second series of experiments, and monomethylaniline and ash-free additives according to Example 1 in a third series of experiments. The octane numbers were determined in each case.
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  Octane number
<tb> Lube oil content <SEP> Naphthenic <SEP> Paraffinic <SEP> Naphthenic <SEP> Naphthenic <SEP> Lube oil <SEP>
<tb> of <SEP> petrol <SEP> lubricating oil <SEP> lubricating oil <SEP> lubricating oil <SEP> lubricating oil <SEP> composition
<tb> + <SEP> ashless <SEP> + <SEP> monomethyl-according to <SEP>
<tb> Addition <SEP> aniline <SEP> Example <SEP> 1
<tb> 0 <SEP> 71 <SEP> 71 <SEP> 71 <SEP> 71 <SEP> 71
<tb> 2, <SEP> 5 "/ 0 <SEP> 70.5 <SEP> 69 <SEP> 70.5 <SEP> 71 <SEP> 71
<tb> 4. <SEP> 0% <SEP> 70 <SEP> 68 <SEP> 70 <SEP> 71 <SEP> 71
<tb> 6, <SEP> 6% <SEP> 69.5 <SEP> 66 <SEP> 69.5 <SEP> 71 <SEP> 71
<tb>
 
Laboratory and operational tests were carried out with the oil compositions according to Example 1 and 2, which related to the rust-reducing effect, to the oxidation stability, and to the wear-reducing effect.

   These additives did their respective effects well.

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  Example 3: 830g phthenic lubricating oil with the following data:
Naphthenic ring content 41 wt. -0/0
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7.0 g of dioctyldithiophosphoric acid ester
10.0 g copolymer of diethylaminoethyl methacrylate and cetyl methacrylate
1.0 g propyl oleate
2.0 g tricresyl phosphate
15.0 grams of monochloronaphthalene
Example 4: 875 g of naphthenic lubricating oil with the following data:
Naphthene aromatic ring content 57% by weight
Viscosity at 1000C 15.8 cSt
Viscosity-density constant 0.8855
100 grams of monomethylaniline
25 g of ash-free additives with the following composition:
10.0 g dihexyldithiophosphoric acid ester
3.0 g copolymer of diethylaminoethyl methacrylate and lauryl methacrylate
1.0 g of isopropyl ricin oleate
2.0 g of tributyl phosphite
9.0g camphor monochrome
PATENT CLAIMS:
1.

   Lubricating oil composition for the fuels used in two-stroke internal combustion engines with spark ignition, characterized in that the lubricating oil composition is 80-95% naphthenic
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Claims (1)

a) the oxidation stability increasing sulfur or. sulfur- and phosphorus-containing organic substances, b) oil-soluble, ash-free detergents, c) rust-preventing compounds, advantageously unsaturated oxyfatty acids or their esters, d) wear-reducing compounds, advantageously chlorine-containing organic compounds, e.g. B. Monochloronaphthalene, e) compounds preventing lead deposits, advantageously organic phosphates or phosphites.