DE2144199B2 - FUELS FOR GASOLINE ENGINES - Google Patents

Description

The invention relates to fuels for gasoline engines with a content of surface-active or washing-active substances petrol-soluble additives.

The increasing density of traffic in large cities and streets is accompanied by pollution of the air we breathe through partially burned or unburned components of the fuels from automobile engines. As an important part of the cause of the incomplete _4C constant burning of petroleum hydrocarbons are as well as for oil spray residues caused by impurities and deposits in the carburetor caused to rich mixture compositions. In the newer automobile engines in particular, the crankcase is vented and the so-called blowby gas is fed back into the intake part or the air filter of the carburetor. Part of the oil mist that occurs in the crankcase is brought into the engine via the carburettor and is mostly burned there, but parts of the oil mist also precipitate in the carburetor interiors. The modern high-performance carburetors are complex structures with very fine channels and bores and precisely calibrated nozzles for spraying and metering the gasoline. If only slight deposits of dirt and residue occur in the fine control elements, nozzles and ducts of these carburettors, the functionality of the carburettors is greatly influenced and worsened. The (, ₀ consequence of this is an incorrect composition of the fuel-air mixture, so that the combustion in the engine does not take place as completely as with clean carburettors. At the same time, however, the ratio of carbon monoxide to carbon dioxide in the exhaust gases is also adversely affected, ie higher proportions of carbon monoxide occur in dirty carburetors.

It is therefore desirable to take appropriate measures to avoid carburetors for automobile engines always to keep clean, to prevent deposits on and in the carburetor parts and if they are dirty Carburetors to achieve a cleaning effect through appropriate additives to the fuel and the Wash deposits and dirt out of the carburetors.

Experiments with known oil- and gasoline-soluble surface-active compounds have so far shown little success. In particular, derivatives of oleic acid, palm kernel oil fatty acid and other fatty acids in the range of C _{) 2} - to ^ (, - carbon atoms have been proposed for this purpose. Amine salts of carboxylic acids and other similar compounds have been tried. In particular, one would suspect that the ethanolamine esters of oleic acid would show a particular cleaning and emulsifying effect. However, as engine tests have shown, this is not the case , they show no effect with the commercially available gasoline.

Also compounds, acid amides and amine salts, with the amine components diethylenetriamine, dipropylenetriamine, triethylenetetiamine show under the Practical conditions possible concentrates only inadequate effect in terms of keeping the Carburetor.

It has now been found that fuels for gasoline engines have no or practically no carburetor residues when they are made from commercially available gasoline and 20 to 2000 ppm of a mixture of the surface or washing-active petrol-soluble components

(A) Diamides from Ci ₂ - to C »-fatty acids and polyamines with ?. up to 6 carbon atoms and 2 to 4 nitrogen atoms and

(b) Esters consist of C _{) 2} - to C ^ -fatty acids and ethanol or propanolamines.

The effect of this combination is increased by using the combinations as a component

(c) sterically hindered by bulky alkyl substituents known per se as antioxidants Phenols and, if appropriate, also

(d) as a solubilizer for components a to c and residue oils from the nonanol and decanol oxo synthesis as top lubricating oil components clogs.

In doing so, certain conditions are expediently observed. to achieve the maximum effect, namely the ratio (a) to (b) should be 1: 8 to 8: 1 or (a) to <b) to (c) 1: 1: 8 to 8: 1: 1.

Fatty acid esters of alkanolamines are oleic acid esters of mono- or di- or triethanolamine. Palmiu-, stearic, undecanoic acid esters and naphthenic acid and tallow oleic acid esters and corresponding esters of propanolamines.

Di-fatty acid amides of polyamines are di-oleic acid (diethylenetriamine) diamide, di-stearic acid (dipropylenetriamine) diamide. Di-palmitic acid (diethylenediamine) -diamide, di-lauric acid- (methyldipropylenetriamine) -diamide or di-undekansäuie- (triethylenetetramine) diamide into consideration.

The following sterically hindered phenols have been found to be particularly effective: 2,4-di-tert-butylphenol, 2,6-di-

tert-butyl-p-cresol, 2,4-dimethyl-6-tert-butylphenol and other dialkylated phenols, cresols and xylenols.

The additives a + b and a + b + c are preferably present in the fuel in amounts of 50 to 500 ppm act.

This washing effect can be illustrated very clearly if one looks at the so-called "Residue on Evaporation Tests, Motor Fuel", described in "Standard Methods for Testing Petroleum, ₀ (Febr. 1956) The InsL of Petroleum, London", £ te 394, served. According to this method, gasoline samples of 100 cm ³ each are mixed with the individual products proposed as carburetor washing components and blown off with hot air like in a car carburetor, then the remaining residues are weighed back in previously weighed glasses. If these residues are each treated with 10 ml of n-heptane, this will more or less remove the residues. After repeated blowing dry with air and further; o reweighing, the percentage of residue dissolved away indicates the washing effect (Table 1).

Table 1

Blank value: cracked gasoline
1000 ppm di-oleic acid (diethylenireamine) diamide 1

1000 ppm mono-oleic acid ester of triethanolamine Il

1000 ppm 2,4-di-tert-butyl-phenol III
1000 ppm of a mixture of:
500 ppm di-oleic acid) diethylene tri-

amine) -diamide I.

+ 500 ppm mono-oleic acid ester of iriethanolamine II

333 ppm I.
+ 333 ppm II
+ 333 ppm III

dissolved away from the residue

20% 69 "/ o

49%

75%

95%

99%

A further intensification of the effect occurs if one acts as a solubilizer for the invention Mixtures to be added instead of the well-known »upper., < lubricating oils «(pure hydrocarbon mixtures) as a further component (d) the residues of the oxo synthesis of nonanol and decanol takes. A complete residue dissolution of 100% is then achieved. the Component (d) is usually in a quantity so ratio of 9: 1 to 1: 9 to the sum of (a) + (b) or (a) + (b) + (c) applied. Particularly good ones Results are obtained with proportions of 1: 1.

A great, unexpected technical advantage is that these products do not are only excellent solvents for gummy residues, but due to their constitution (higher alcohols, Ethers, acetals and aldehydes) also burn far better in the engine than the top lubricating oils previously used.

In a BASF single-cylinder test engine with a displacement of 332 cm ³ (bore = 65 mm diameter, stroke = 100 mm), fuels according to the invention were run in 50-hour test runs at a constant speed of <2000 rpm and an hourly fuel consumption rate of 1.61. r »pr Mntnr was modified so that 10% of the

do puff gases were returned to the crankcase below the oil level and from there into the air filter of the intake line of the carburetor (Solex Type 26VFIS).

A mixture was used as the lubricating oil for these experiments 90 parts by weight of unalloyed mineral base oil and 10% of an HD oil are used. The fuel passed made from a highly olefinic, non-stabilized cracked gasoline with a high gum content (ASTM D 529). After 50 hours of test runs, the fuel turned black without the specified additives Deposits on the air funnel and in the throttle valve area of the carburetor as well as on the shaft of the inlet valve Table 2 shows the poor cleaning effect of each of the individual mixture components alone and that the combination with the same amount of application the cleaning effect of the respective Exceeds individual components by leaps and bounds. The evaluation of the degree of contamination in the carburetor (especially in the Venturi tube) it makes sense to use the ratio of the dirty to the clean area.

Table 2

The assessment is based on a so-called »Demerit rating«, with a completely residue-free one The carburetor and the associated C-Class system were given a rating of 10. If soiling occurs, a lower rating number is used according to the strength and quantity. The blank value (no cleaning additive in the fuel), is synonymous with "total pollution" rated 0. "Total pollution" means that the surface is completely covered, which comes into contact with fuel in the venturi tube, in the throttle valve area of the carburetor and Deposits on the inlet valve of the test engine.

Rating number

(Demerit rating)

Blank value: contains petrol

Cracked gasoline ^

A 1000 ppm di-oleic acid (diethylene tri-

amine) -diamide 5

B 1000ppm monooleic acid ester of the tri

ethanolamine 0

C 1000 ppm residual oil from the oxo synthesis of nonanol 0

D 1000 ppm 2,4-u-tert-butyl-phenol 3

F. 500 ppm di-oleic acid (diethylene tri-

amine) -diamide
+ 500 ppm monooleic acid ester of the tri

ethanolamine 7

F 250 ppm di-oleic acid (diethylenetriamine) diamide

+ 250ppm monooleic acid ester of triethanolamine

+ 500ppm residual oil from the oxo synthesis by Nonaol 9

j 200 ppm di-oleic acid (diethyleniamine) diamide

+ 100 ppm monooleic acid ester of triethanolamine

+ 200 ppm 2,4-di-tert-butylphenol

+ 500 ppm residual oil from the oxo synthesis of nonanol 10

example 1

Two 2-1 class cars of the same type and of the same type Make and approximately the same mileage (± 7000 km) were each with the same premium gasoline and the same lubricating oil in pewing operation at the same time in the same city. The vehicles had a mileage of 67000 and 74000 km and were, especially the engine, in technical perfect condition.

It was found that in the first vehicle that was operated with additional fuel, after 20,000 kilometers no reduction in the usual blackish deposits in the carburetor and could be determined in the mixture intake system. However, if the product combination G from Table 2 Added to the fuel of the second vehicle in an amount of 200 ppm, this already occurred after 3000 kilometers on the carburetor parts there is a clear decrease in the pollution that has already formed. To About another 5,000 kilometers the dirt on the walls of the carburetor had almost disappeared.

Example 2

A Fiat 600D engine with Weber carburettors was idling on an engine test bench. At the start of the experiment, the fuel-air mixture was regulated so that the exhaust gas was between 4.0 and Contained 4.5 vol% carbon monoxide. The cold water temperature was held at 45 ± 1 ° C. The fuel used was an unstabilized gasoline with a Pb content of 0.6g / l.

In the tests with the aforementioned fuel, after about 15 hours of testing, the CO content in the exhaust gas, which was due to the dirt deposits in the carburetor. Included maximum values of up to 7% by volume CO were achieved after 50 hours of testing measured.

However, if 200 ppm of the product combinations contained in the fuels according to the invention were added to the fuel and the engine was run under otherwise identical conditions, no increase in the CO content could be determined even after 75 hours of operation. A visual inspection of the carburetor and the intake system of the engine of the showed that no or only very little dirt had built up.

Claims (3)

Patent claims: 1. Fuels for Otto engines, consisting of the commercially available gasoline and 20 to 2000 ppm a mixture of the surface- or washing-active petrol-soluble components a) Diamides from C _ir to C _{2 (r} fatty acids and polyamines with 2 to 6 carbon atoms and 2 to 4 nitrogen atoms and ι ο b) Esters of C, _r to C ₂₀ fatty acids and ethanol or propanolamines and optionally c) sterically known as antioxidants due to space-filling alkyl substituents hindered phenols, and optionally further d) as a solubilizer for components a to c and residual oils as top-lubricating oil components from the nonanol and decanol oxo synthesis. 2. Propellants according to claim 1, containing 50 to 500 ppm of components a + b or a + b + c. 3. Fuels according to claim 1, in which the weight ratio (a) to (b) 1: 8 to 8: 1 or (a) to (b) to (c) is 1: 1: 8 to 8: 1: 1 and the sum of (a) + (b) or (a) + (b) + (c) to the solubilizer (d) is in a weight ratio of 9: 1 to 1: 9.