GB1587949A - Gasoline fuels for internal combustion engines - Google Patents

Description

(54) GASOLINE FUELS FOR INTERNAL COMBUSTION ENGINES (71) We, BASF AKTIENGESELLSCHAFT, a German Joint Stock Company of 6700 Ludwigshafen Federal Republic of Germany, do hereby declare the invention, for which we pray that a Patent may be granted to us, and the method by which it is to be performed. to be particularly described in and by the following Statement: The present invention relates to gasoline fuels for internal combustion engines. containing diamides of fatty acids and polyamines as additives to assist in cleaning, or keeping clean, their carburetors.

As described in detail in German Laid-Open Application DOS 2.144,199. it is desirable to admix to gasoline fuels for internal combustion engines additives which clean. or keep clean.

their carburetors.

Our British Patent Specification No. 1410788 describes and claims gasoline fuels for internal combustion engines which contain. as surface-active or detergent gasoline-soluble components: a) one or more diamides of fatty acids of 11 to 20 carbon atoms with aliphatic polyamines of 2 to 6 carbon atoms and 2 to 4 amino nitrogen atoms and b) one or more esters of naphthenic acids or fatty acids of 11 to 20 carbon atoms with ethanolamines or isopropanolamines. with or without c) one or more phenols which are sterically hindered by the presence of bulky (space-filling) alkyl substituents and which are known per se as antioxidants and furthermore with or without d) as solubilizer for components (a) to (c) and as upper cylinder lubricant component.

residual oil from the oxysynthesis of nonanol and decanol.

We have found that the action of the gasoline additives can be improved further and in particular any possible corrosion can be prevented if the above component (b) is replaced by one or more condensation products of saturated or unsaturated carboxylic acids of 8 to 20 carbon atoms with from 2 to 20 moles (per mole of carboxylic acid) of ethylene oxide and/or propylene oxide.

Suitable carboxylic acids for the condensation products (b) for use in the present invention are above all fatty acids. Examples include decanoic acid, undecanoic acid. dodecanoic acid.

lauric acid. oleic acid. stearic acid, palmitic acid. naphthenic acids and castor oil fatty acids.

These acids may be either linear or branched and may even contain a five-membered or six-membered ring in the molecule. The carboxylic acids. preferably fatty acids. are condensed. in optional sequence. with from 2 to 20 moles (per mole of acid) of ethylene oxide and/ or propylene oxide. for example with from 1 to 10 moles of ethylene oxide and from 1 to 10 moles of propylene oxide. or are condensed with from 2 to 20 moles of a mixture of these oxides. Preferred compounds simultaneously contain from two to four units of ethylene oxide and from 2 to 5 units of propylene oxide.

Suitable diamides (a) derived from polyamines are di-oleyl -diethylenetriaminediamide.

di-stearyl -dipropylenetriamine diamide. ' di-palmityl -diethylenediamide, di-lauryl -methyldipropylenetriaminediamide and di-undecanoyl -triethylenetetraminediamide.

Particularly effective sterically hindered phenols (c) have been found to be 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 amounts of additives a + b or a + b + c employed are in general from 20 to 2.000 ppm. preferably from 50 to 500 ppm. by weight. Preferably. the weight ratio a:b is from 1:8 to 8:1 or, if c is present, the weight ratio a:b:c is from 1:1:8 to 8:1:1.

Further, it has been found that in general residual oils from oxo reactions, and in particular oxo reactions starting from olefins of 3 to 16 carbon atoms, preferably of 3 to 12 carbon atoms, are not only excellent solubilizing agents (d) but also impart very good low temperature properties to the mixtures of compounds to be added to the gasoline. This applies particularly to the residual oils from the oxo process for the preparation of butyraldehyde and butanol.Such residual oils may, for example, be characterized as follows: Residual oil from the synthesis of butanol: density at 200C 0.851 g/cm3 pour point (DIN 51,583) -60 C acid number from 0.05 to 0.4 mg KOH/g Abel-Pensky flash point > 60"C Marcusson flash point 75 to 850C viscosity at 200C 5 to 10 cSt viscosity at 50"C 2 to 4 cSt boiling range, 5% by volume below 175 + 10 C 50% by volume below 190 + 10 C 90% by volume below 210 + 10 C ash content less than 1 % Residual oils from the synthesis of non an ol/decanol:: Boiling range, start > 230 C 50% by volume below about 330"C 80% by volume below about 350"C density at 20"C from 0.85 to 0.89 pour point (DIN 51,583) < -20 C Pensky-Martens flash point > 1000C ash content < 1% A further surprising advantage of the residual oils from the oxo reaction, especially of the residual oils from the synthesis of butanol, was found on combining these components, which clean the carburetor, with the petroleum-based upper-cylinder lubricant oils which have long been known and which serve to clean the valves.

If only petroleum-based upper-cylinder lubricant oils are employed in the gasoline additives, amounts of these oils of, for example, from 0.08 to more than 2% by volume are required for an adequate cleaning action on the valves.

If, however, the additives to be employed according to the invention are combined with a petroleum-based upper-cylinder lubricant oil, and if, in the additives according to the invention, a residual oil from the oxo reaction, especially a residual oil from the synthesis of butanol, is employed, the amount of petroleum-based upper-cylinder lubricant oil required to achieve an adequate cleaning action on the valves is reduced substantially.

Accordingly, the combination of residual oil from the oxo reaction, a petroleum-based upper-cylinder lubricant oil and the other compounds to be employed as additives according to the invention contributes substantially to protection of the environment, since substan tially less lubricant oil is required and. as is known, the oxygen-containing residual oils from the oxo reaction undergo far readier combustion in the engine, because of their constitution (higher alcohols, esters, ethers, acetals and aldehydes) than do petroleum-based lubricant oils.

Suitable petroleum-based upper-cylinder lubricant oils are the conventional lubricant oils or lubricant oil cuts. A particularly suitable lubricant oil is characterized by, for example, the following data: color number (ASTM method) 2 density (at 15"C) 9,862 g/cm3 viscosity (at 200C) 30 mm2/s viscosity (at 50"C) 10.3 mm2/s Pensky-Martens flash point about 709C pour point (DIN 51,583) < -20 C acid number 0.01 mg KOH/g The fuels for gasoline engines are characterized by the conventional properties.Their volatility ranges, at 1000F (37.8"C) from 6 Ibs/sq.in. (0.41 bar) to 16 Ibs/sq.in. (1.03 bars) and covers a range of "50% points" in the ASTM D-86 test from 1700F (77"C) to 2700F (132"C). The ASTM end point of motor gasoline is from 350"F (176"C) to 4500F (232"C) Complete specifications for motor gasolines are given in detail in United States Federal Specification VV-M-561 a-2, Oct. 30 1954, under the headings Fuel M, Regular and Premium Grades, Classes A, B and C.

Advantageously, the compounds to be used according to the invention are added to the gasoline which is to be upgraded by first preparing a concentrate, if necessary with the aid of a solubilizing agent, eg. toluene or a gasoline fraction containing a higher proportion or aromatics, which concentrate can be continuously metered into the motor fuel, preferably in the refinery. The concentrate may contain additional carburetor cleaning components, especially the polycarboxylic acid esters disclosed in Belgian Patent 807,489. Such overall combinations have a particularly advantageous effect in that they clean the intake section, the carburetor and the intake valves of gasoline engines, and keep them clean.

The fuels according to the invention may contain other conventional gasoline additives, eg.

lead alkyls, deicing additives, corrosion inhibitors, gum inhibitors and dyes.

The washing action of the fuels according to the invention can be illustrated very clearly by employing the "Residue on Evaporation Tests. Motor Fuel" described in "Standard Methods for Testing Petroleum (Febr. 1956) The Inst. of Petroleum. London", page 394.

According to this method, 100 cm3 gasoline samples are mixed with the various products proposed as components for washing the carburetor and are blown off with hot air, as happens in an automotive carburetor; the residues left are then weighed in glass dishes which have been weighed beforehand. If these residues are each treated with 10 ml of n-heptane, they dissolve to a greater or lesser extent. After again blowing the dishes dry with air, and reweighing, the percentage of dissolved-off residue is obtained, and this is a measure of the washing action. Data for various additives appear in Table 1 which follows, the gasoline in each case being obtained by cracking.

Table 1 proportion of amount and nature of additive residue dissolved off blank: 22 O/c 1,000 wt ppm of the diamide A obtained from diethylenetriamine and 2 moles of oleic acid 66% 1,000 wt ppm of the mono-oleyl ester B obtained by reacting oleic acid with 2 moles of ethylene oxide and 3 moles of propylene oxide 48% 1,000 wt ppm of 2,4-di-tert.-butyl- phenol C 73% 1,000 wt ppm of a mixture of 500 wt ppm of the diamide A obtained from diethylenetriamine and 2 moles of oleic acid + 500 wt ppm of the mono-oleyl ester obtained by reacting oleic acid with 2 moles of ethylene oxide and 3 moles of propylene oxide 95% 333 wt ppm A+ 333 wt ppm B + 333 wt ppm C 99% The effect is boosted further if, instead of using the conventional upper-cylinder lubricant oils (pure hydrocarbon mixtures) as solubilizing agents for the mixtures to be added according to the invention, the residues from the oxo reaction especially from the manufacture of butanol, are instead used as additional component (d). In that case, 100% dissolution of the residue is achieved. Component (d) is in general employed in a weight ratio of from 9:1 to 1: 9 with respect to the sum of (a) +(b)ora) + (b) + (c), as the case may be. Particularly good results are achieved with a ratio of 1 : 1.

A further great and unexpected technical advantage under these conditions is that the additives are not only excellent solvents for gummy residues but also undergo far readier combustion in the engine, because of their constitution (higher alcohols, ethers, acetals and aldehydes) than do the upper-cylinder lubricant oils conventionally used.

Test Results Using a BASF single-cylinder test engine with a piston displacement of 332cm3 (bore = 65 mm diameter, stroke = 100 mm), fuels according to the invention were run in tests of 50 hours duration, at a constant speed of 2,000 rpm and with an hourly fuel consumption of 1.6.1. The engine was modified so that 10% of the exhaust gases were recycled to the crank casing below the oil level and were passed from there into the air filter of the intake line of the carburetor (Solex Type 26VFIS -Solex is a Registered Trade Mark).

The lubricating oil used for this test was a mixture of 90 parts by weight of non-blended petroleum base oil and 10 parts by weight of a heavy duty oil. The fuel consisted of a high-olefin unstabilized gasoline obtained by cracking, with a high gum content (ASTM D 529). After test runs of 50 hours, the fuel without the stated additives was found to have produced black deposits on the diffuser and in the region of the throttle valve of the carburetor. as well as on the shaft of the inlet valve. Table 2 which follows shows that the individual components of the mixture alone have a slight cleaning action, whilst when using the same amount of the combination, the cleaning action abruptly exceeds that of the individual components. The degree of soiling in the carburetor (especially in the Venturi tube) is assessed in terms of the ratio of the soiled surface to the clean surface.

The assessment in Table 2 which follows is based on a demerit rating, a carburetor, and intake system, completely free of residues being rated 10. If soiling is found, a lower rating is given, in accordance with the intensity and amount of soiling. The blank (without any cleaning additive in the fuel). equivalent to total soiling, is rated 0. Total soiling means that the surface coming into contact with the fuel in the Venturi tube and in the throttle valve region of the carburetor is completely covered, and that deposits are found on the intake valve of the test engine. Throughout the Table figures in ppm are by weight and the gasoline is automotive gasoline containing gasoline obtained by cracking.

Table 2 Demerit Blank Amount and narure of additive rating 0 l *000 ppm of the diamide of diethylenetri- amine with 2 moles of oleic acid (A) 5 II 1,000 ppm of a ricinoleic acid ester obtained by reaction with 3 moles of propylene oxide and 3 moles of ethylene oxide (B) 0 III 1.000 ppm of residual oilfrom the oxo synthesis of nonanol IV 1.000 ppm of 2,4-di-tert. -butyl-phenol (C) 3 V 500 ppm of the diamide of diethylene triamine with 2 moles of oleic acid + 500 ppm of ricinoleic acid ester obtained by reaction with 3 molesofpropylene oxide and 3 moles of ethylene oxide 8 VI 250 ppm of the diamide of diethylenetri amine with 2 moles of oleic acid + 250 ppm of ricinoleic acid ester obtained by reaction with 3 moles of propylene oxide and 3 moles of ethylene oxide + 500 ppm of residual oil from the oxo synthesis of nonanol 9 VII 200 ppm of the diamide of diethylenetri amine with 2 moles of oleic acid + 100 ppm of ricinoleic acid ester obtained by reaction with 3 moles of propylene oxide and 3 moles of ethylene oxide + 200 ppm of 2,4-di-tert. -butylphenol + 500 ppm of residual oil from the oxo synthesis of nonanol 9.5 VIII 100 ppm A) 50 ppm B) 50 ppm C) 800 ppm D) 9.0 IX 100 ppm A) 50 ppm B) 50 ppm C) 400 ppm D) 400 ppm E) 9.0 X 200 ppm A) 100 ppm B) 100 ppm C) 500 ppm D ) 9.5 XI 100 ppm A) 50 ppm B) 50 ppm C) 800 ppm E) 8.5 XII 100 ppm A) 50 ppm B) 50 ppm C) 400 ppm D) 9.0 D = residual oil from the manufacture of butyraldehyde and butanol by oxo reaction.

E = petroleum-based upper-cylinder lubricant oil.

Accordingly, the above combinations show about the same washing action as the additives disclosed in German Laid-Open Application DOS 2,144.199, but with the advantage that when using the mixtures according to the invention virtually no corrosion is detectable in the carburetor.

The solubilizing and synergistic properties of the oxo-oils in combination with the products according to the invention are illustrated by the Example which follows.

EXAMPLE A mixture of 10 g of the diamide of diethylenetriamine with 2 moles of oleic acid, 5 g of ricinoleic acid ester (obtained by reacting ricinoleic acid with 3 moles of propylene oxide and 3 moles of ethylene oxide) and 5 g of 2.4-di-tert.-butylphenol is dissolved, in a beaker. by heating to 50"C. On cooling to room temperature, the mixture again turns cloudy. After standing for 3 days at room temperature, 2.4 g of sediment are obtained on filtering the mixture. After standing for 3 days at 0 C, the mixture has almost set solid; filtration gives 7.2 g of sediment.

However, if 40 g of residual oil from the synthesis of butanol are added to the above components and the procedure described in the Example is followed, the solution of the substances remains clear even after standing for several weeks at OOC. The pour point of the solution. measured according to DIN 51,583, is below -30 C.

Testing the cleaning action on the carburetor and intake system Some of the substances listed in Table 2 were admixed to the fuel of an Opel-Kadett 1.2 liter test engine (55 h.p. at 5,200 rpm). (Opel is a Registered Trade Mark). The test engine was run under the following conditions: conditions: test duration: 40 hours test cycle program: 0.5 min. idling at 1,000 rpm 1 min. at 3,000 rpm and 15 h.p.

(corresponding to 80 km/h) 1 min at 1,300 rpm and 5.5 h.p.

(corresponding to 35 kg/h) 1 min. at 1,850 rpm and 8.5 h.p.

(corresponding to 50 km/h) Engine running conditions: temperature of engine oil in sump 94 + 2"C temperature of coolant (cylinder head outlet) 92 + 2"C air intake temperature (when idling) 100"C carbon monoxide content in exhaust gas, when idling, at start of test 3.5 + 0.5% by volume All the tests were carried out under the above constant engine conditions and the same fuel was used in all tests with the Opel-Kadett engine.

Table 3 below gives the results of the engine tests in the Opel-Kadett engine.

The cleanliness of the carburetor and valves was assessed on the "CRC rating" scale for diesel engines (CRC merit rating: 10.0 = 100% clean). The fuel used contained gasoline obtained by cracking.

TABLE 3 Additive Amount of Additive CRC rating Residue on Substances or (ppm, by carburetor intake intake valve Substances used volume) valve (mg) Blank - 7.0 7.5 282 - 7.3 7.5 296 - 7.0 7.0 316 A 250 8.0 8.0 200 B 500 7.3 7.5 276 C 500 7.0 7.5 264 A 250 8.5 8.0 212 +B +125 A 250 +B +125 9.5 8.0 203 +C +125 A 100 +B + 50 9.0 9.0 98 +C + 50 +E + 800 A 100 +B + 50 9.0 8.5 148 +C + 50 +D +400 A 100 +B + 50 +C + 50 9.2 9.5 52 +D +400 +E +400 A 200 +B +100 +C +100 9.5 9.8 17 +D +400 +E +400 A = diamide of diethylenetriamine with 2 moles of oleic acid B = ricinoleic acid ester obtained by reacting ricinoleic acid with 3 moles of propylene oxide and 3 moles of ethylene oxide C = 2.4-di-tert.-butylphenol D = residual oil from the oxo-synthesis of butanol E = petroleum-based upper-cylinder lubricant oil WHAT WE CLAIM IS: 1.A gasoline fuel for an internal combustion engine which contains as additives.

a) one or more diamides of fatty acids of 11 to 20 carbon atoms and aliphatic polyamines of 2 to 6 carbon atoms and 2 to 4 amino nitrogen atoms and b) one or more condensation products of saturated or unsaturated carboxylic acids of 8 to 20 carbon atoms with from 2 to 20 moles per mole of carboxylic acid of ethylene oxide and/or propylene oxide.

2. A fuel as claimed in claim 1. which contains. as a further component, c) one or more phenols which are sterically hindered by the presence of bulky alkyl substituents and are known per se as antioxidants.

3. A fuel as claimed in claim 1 or 2 which contains. as a further component, d) one or more residual oils from an oxo reaction. as solubilizing agents for components a to c and as an upper-cylinder lubricant component.

4. A fuel as claimed in claim 3. in which component d) is a residual oil from the manufacture of butyraldehyde and butanol by the oxo reaction.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (9)

1. **WARNING** start of CLMS field may overlap end of DESC **.

   TABLE 3 Additive Amount of Additive CRC rating Residue on Substances or (ppm, by carburetor intake intake valve Substances used volume) valve (mg) Blank - 7.0 7.5 282 - 7.3 7.5 296 - 7.0 7.0 316 A 250 8.0 8.0 200 B 500 7.3 7.5 276 C 500 7.0 7.5 264 A 250 8.5 8.0 212 +B +125 A 250 +B +125 9.5 8.0 203 +C +125 A 100 +B + 50 9.0 9.0 98 +C + 50 +E + 800 A 100 +B + 50 9.0 8.5 148 +C + 50 +D +400 A 100 +B + 50 +C + 50 9.2 9.5 52 +D +400 +E +400 A 200 +B +100 +C +100 9.5 9.8 17 +D +400 +E +400 A = diamide of diethylenetriamine with 2 moles of oleic acid B = ricinoleic acid ester obtained by reacting ricinoleic acid with 3 moles of propylene oxide and 3 moles of ethylene oxide C = 2.4-di-tert.-butylphenol D = residual oil from the oxo-synthesis of butanol E = petroleum-based upper-cylinder lubricant oil WHAT WE CLAIM IS: 1.A gasoline fuel for an internal combustion engine which contains as additives.

   a) one or more diamides of fatty acids of 11 to 20 carbon atoms and aliphatic polyamines of 2 to 6 carbon atoms and 2 to 4 amino nitrogen atoms and b) one or more condensation products of saturated or unsaturated carboxylic acids of 8 to 20 carbon atoms with from 2 to 20 moles per mole of carboxylic acid of ethylene oxide and/or propylene oxide.
2. 2. A fuel as claimed in claim 1. which contains. as a further component, c) one or more phenols which are sterically hindered by the presence of bulky alkyl substituents and are known per se as antioxidants.
3. 3. A fuel as claimed in claim 1 or 2 which contains. as a further component, d) one or more residual oils from an oxo reaction. as solubilizing agents for components a to c and as an upper-cylinder lubricant component.
4. 4. A fuel as claimed in claim 3. in which component d) is a residual oil from the manufacture of butyraldehyde and butanol by the oxo reaction.
5. 5. A fuel as claimed in any of claims 1 to 4, which contains from 20 to 2,000 ppm by

   weight of components a + b or a + b + c + d.
6. 6. A fuel as claimed in any of claims 1 to 4, which contains from 50 to 1,000 ppm by weight of components a + b or a + b + c + d.
7. 7. A fuel as claimed in any of claims 1 to 6, in which the weight ratio a: b is from 1: 8 to 8: 1 or, if c and/or dare present, the weight ratio a: b: c is from 1 : 1 8 to 8:1:1 and the weight ratio of (a + b) : d or (a + b + c) : d is from 9 1 to 1: 9.
8. 8. A fuel as claimed in any of claims 1 to 7, in which component (b) is a condensation product which contains simultaneously from 2 to 4 units of ethylene oxide and from 2 to 5 units of propylene oxide.
9. 9. A fuel as claimed in claim 1 and substantially as hereinbefore specifically described or exemplified.