DE2417788A1 - Detergent additives for petrol - consisting of poly-carboxylic acid ester amide-imides - Google Patents

Abstract

In the parent patent, detergent additives for petrol, of formula (I) (where A is the hydrocarbon gp. of a mono-, bi- or tri-cyclic non-aromatic acid with m = n COOH gps; R1 is the gp. of a 3-18C alcohol; -NR2R3 is the gp. of an aliphatic, cycloaliphatic or aromatic primary or secondary 2-36C amine; m and n are 1-5, and m + n is 3-6; at least one of R1 R2 and R3 contains 6 or more C atoms) were disclosed. In the patent of addtn. the additives are of formula (II) (where A is a gp. of an acid as above with M m+n+l COOH gps. R4-N is the gp. of a primary and -NR2R3 the gp. of a primary or sec amine; m is 0-4, n is 0-6, l is 0, 24 or 6, and m+n+l is 3-6, l is greater than O if m is greater than O; at least one of R1 to R4 contains 6 or more C atoms). Carbon deposits on valves, carburetter, etc. are prevented, when the additives are present in the petrol at 10-1000 (50-300) ppm.

Description

Use of amides of cyclic polycarboxylic acids as additives to fuels. Addition to patent. .O. ... (Patent application P 22 56 6901-42) The main patent relates to the use of ester amides of cyclic polycarboxylic acids of the formula in which A is the hydrocarbon residue of a mono-, bi- or tricyclic non-aromatic polycarboxylic acid with m + n carboxyl groups, R1 is the residue of an alcohol with 3 to 18 carbon atoms, R2-N-R3 is the residue of an aliphatic, cycloaliphatic or aromatic primary or secondary amine with 2 to 36 carbon atoms and m and n denote the numbers 1 to 5, the sum of m + n being 3 to 6 and at least one of the ester or amide radicals being derived from alcohols or amines with at least 6 carbon atoms, as an additive on fuels for gasoline engines.

In a modification of the subject matter of the main patent, it has now been found that compounds of the formula II are equally suitable as additives to fuels for gasoline engines in which A is the hydrocarbon residue of a mono-, bi- or tricyclic non-aromatic polycarboxylic acid with m + n + 1 carboxyl groups, R is the residue of an alcohol with 3 to 18 carbon atoms, R4-N is the residue of a primary and R2-NR) is the residue of a primary or secondary amine, m the numbers 0 to 4, n the numbers 0 to 6, 1 the numbers 0, 2, 4 or 6, the sum of m, n and 1 being 3 to 6 and at least one of the esters -, the amide or imide residues differ from alcohols or

Derives amines having at least 6 carbon atoms and furthermore 1 means a number greater than 0 if m is greater than O.

Accordingly, pure amides, amide-imides, ester-imides and ester-amide-imides come - but not ester amides, which are the subject of the main patent.

Compounds to be used with preference are those in which at least two of the radicals R1, R2, R3 or R4 have at least 8 carbon atoms.

For the starting acids, the alcohols, the amines and the application of the compounds of the formula II, the details of the main patent apply unchanged.

Amides or imides of the formula II are prepared in a manner known per se.

Amides of the formula II are expediently prepared in such a way that one the free acid, the anhydride or the anhydride acid with or without a solvent with the amine, in particular a secondary amine, is heated in excess for several hours, the water formed is distilled off or removed from the system and after the reaction has ended optionally the solvent and the excess amine in a manner known per se, e.g. by distillation, removed The corresponding imides are formed with the same Conduct of the reaction if, in particular, primary amines are used.

If some of the compounds according to the invention still have free carboxyl groups, so it seems appropriate to the fuel that these compounds according to the invention contains at least an equivalent amount corresponding to the free carboxyl groups of amines, such as fatty acid diethylenetriamine, oleic acid dipropylenetriamine, dioleic acid diethylenetriamine, to be added, so that there are no more free acidic groups.

A prerequisite for the use of these polycarboxylic acid compounds is their good oil and gasoline solubility. It is therefore advisable to use long-chain ones as possible Remains R1 to R4 to choose from. As a rule, you will therefore choose leftovers that are still there have more than 8 carbon atoms, preferably 9 to 18 carbon atoms. Even one will expediently use compounds of the formula II which have more than two of the long-chain Residues per molecule, e.g. 5 to 6 residues of alcohols and amines with preferably 9 to 18 carbon atoms.

The compounds to be used according to the invention should be expedient a minimum solubility of about 0.1 g / l gasoline, advantageously at least 1 g / l gasoline exhibit. It is expedient to add them to the gasoline to be improved in such a way that that initially - e.g. with the help of a solubilizer such as toluene, or a Gasoline fraction with a larger proportion of aromatics - a concentrate is prepared that continuously metered into the motor fuel, preferably in the refinery can be. This concentrate can contain other carburetor cleaning components, for example Fatty acid amides or Polyamides contain, with the amounts just so be chosen large that the coking described in the main patent on the valve not yet entered. This is usually less than 200 to 500 ppm in the finished product Fuel.

The fuels for gasoline engines have properties that are known per se The range of their volatility extends from to 100 ° F (37.8 ° C) 6 1bs / sq.i. (0.41 bar) to 16 1bs / sq.in. (1.03 bar) and over a range of "50 % Points "in the ASTM D-86 test from 170 ° F (77 ° C) to 270 ° F (132 ° C). The ASTM end point of motor gasoline is between 350 ° F (176 ° C) and 450 ° F (232 ° C). Full specification for motor gasoline are defined in detail in the United States Federal Specification VV-M-561 a-2, Oct. 30, 154, as Fuel M, Regular and Premium grades of classes An B and Ca Example 1 bicyclooctentetracarboxylic acid di-2-ethylhexylimide 248 parts of bicyclooctentetracarboxylic acid dianhydride are dissolved in 1500 parts by volume of dimethylformamide at 60 ° C and then 258 Parts of 2-ethylhexylamine added. The reaction mixture is heated to 40 for about 8 hours heated to 15,000 and then the solvent is distilled off in vacuo After cooling, 456 parts (97 of the theory) Imid9 get a solidified mass a pour point of 84 to 89 ° C, an acid number of 10 and a nitrogen content from 6.0 9 (,.

According to the information in Example 1, the following were further prepared: acid or Anhydride amine content acidity compound mol mol% number 2 cyclohexane hexacarbon 5) 7.7 5-10 acid tri-hexylimide 5 cyclohexane hexacarbon- 1 X 5.0 5-10 acid tri-tridecylimide 4 bicyclooctentetracarbonr 1 2 6.5 5-10 acid di-benzylimide example 5 bicyclooctentricarboxylic acid tr-idecylimide-tridecylamide 222 parts of bicyclooctentricarboxylic anhydride are dissolved in 1000 parts by volume of dioxane and in the heated to 10Q0C mixture of 1000 parts by volume of dioxane and 650 parts of tridecylamine are then entered Heated under reflux for 8 hours and dioxane and excess tridecylamine in vacuo distilled off.

After cooling, a paste-like mass of 755 parts is obtained (92 % of theory) with a nitrogen content of 5.0.

Example 6 Cyclohexanhexacarboxylic acid hexa- (di-tridecy amide 174 parts Cyclohexanhexacarboxylic acid are dissolved in 1000 parts by volume of dimethylformamide and in the heated to 1300C mixture of 700 parts of di-tridecylamine in 600 parts by volume Dimethylformamide entered. After 54 parts of water have been separated off, the Reaction solution concentrated in vacuo, leaving dimethylformamide and excess tridecylamine be separated.

674 parts (94% of theory) of a pasty mass are obtained with a Nitrogen content of 5> 45 ffi and an acid number of 7.

Example 7 Cyclohexanhexacarboxylic acid hexa- (di-2-ethylhexyl) amide 174 parts of cyclohexane hexacarboxylic acid are made up in small portions in 775 parts 1000C heated di-2-ethylhexylamine entered. Subsequently, within 8 hours 54 parts of water removed from the circuit. After the excess amine in vacuo is distilled off, the crystalline residue is washed with petroleum ether and dried. 456 parts (90 of theory) with a nitrogen content of 5.2% and an acid number of 8.

According to the information in Example 7, the following are obtained in the same way: S @ ure or an @ -Beihydride amine content acid game compound mol mol% number 8 bicyclooctene-b-etracar- 1 4 7.7 boric acid tetra (di-2-ethylhexyl) amide 9 bicyclooctene tetracar- 1 4 9.1 7 carbonic acid tetra (dihexylamide) Example 10 bicyclooct @ ntricarboxylic acid 2-ethylhexylimide-2-ethylhexylamide 222 parts of bicyclooctentricarboxylic anhydride and 129 parts of 2-ethylhexylamine are dissolved in 500 parts by volume of dimethylformamide, heated to reflux; within 4 18 parts of water are distilled off for hours. Then you give another 129 Add 2-ethylhexylamine and separate another 18 parts of water within 2 hours away. After removing the solvent Cm vacuum, 450 parts remain Imld amide back (97% of theory) with a nitrogen content of 6.3% and a Acid number of 7.

According to Example 10, the following are also obtained: acid or A @ - N-hydride Amine content acidity compound mole mole% number 11 bicyclooctentetracarbon 1 3 5.15 5 acid-2-ethylhexylimidbis (di-2-ethylhexyl) amide 12 cyclohexane hexacarbon- 1 5 5.5 7 acid hexylimide-tetra- (di-2-ethylhexyl) -amide 13 bicyclooctentracarbon- 1 3 5.4 10 acid-n-hexyllmid-bisdi-2-ethylhexy @ am @ Example 14 Bicyclooctentetracarboxylic acid 2-ethylhexylimide-di-2-ethylhexyl ester 248 parts of bicyclooctentetracarboxylic acid in 1500 parts by volume of dimethylformamide dissolved, treated with 129 parts of 2-ethylhexylamine and refluxed for 4 hours at 150.degree @rhitzt. There 18 parts of water are split off. After the end of the reaction one sets 260 parts of 2-ethylhexanol are added and the mixture is heated under reflux for a further 6 hours, with again 18 parts are distilled off. The solvent is then distilled off in the Vacuum and get 589 parts of esterimide with a nitrogen content of 2.5 ß and an acid number of 10.

According to the information in Example 14, acid is obtained in the same way or an alco- ge-hydride amine hold acid play compound mole mole mole% number 15 bicyclooctentetracar- 1 1 2 2.7 5 bonsäurehexylimid-2-ethylhexylbutylester 16 Bicyclooctentricarbon- 1 1 1 3,3 7 acid-2-ethylhexylimldn-hexylester 17 Cyclohexanhexacarbon- 1 2 2 3.7 10 acid-di-2-ethylhexylimide-di-2-ethylhexyl ester The invention Fuels contain the compounds obtainable according to Example 1 to 17 in the Usually in amounts up to 0.0 percent by weight; si @ can do more, especially at contain known additives, such as fatty acid amides, fatty acid polyamides, ethers the polyalkylene glycols or anti-icing agents, dyes and corrosion inhibitors, Application example 1 In a BASF single-cylinder test engine with a displacement of 552 cm3 (bore = 65 mm diameter, stroke = 100 mm) were carried out in 50-hour test runs at a constant speed of 2000 rpm and an hourly fuel flow of 1.6 1 fuels according to the invention drove. The engine was modified so that that 10% of the exhaust gases are 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) were directed.

The assessment is based on a so-called "Demerit rating", with a completely residue-free carburetor and the associated intake system receives the rating 10. If soiling occurs, the thickness will correspond and amount used a lower rating number. The blank value (i.e. no cleaning active additive in the fuel), equivalent to a "total pollution", is rated 0. "Total pollution" means complete coverage the surface that 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. This demerit rating showed a degree of soiling with dioctyl phthalate and other dicarboxylic acid esters of 1 in the carburetor at 1000 ppm The inlet valves were after the 50 hour run heavily soiled with black asphalt-like residues.

However, the test runs (50 h) were carried out with 500 DSM bicyclo-acid-octentricarbon-tridecylimide-tridecylamide driven so the carburetor was clean, i.e. the demerit rating gave the number 10.

The inlet valves were left without residue and looked very clean. Similar results were obtained with 1000 ppm of bicyclooctentetracarboxylic acid di-2-ethylhexylimide or cyclohexane hexacarboxylic acid tri-dodecylimide.

APPLICATION EXAMPLE 2 A Fiat engine was used on an engine test bench Type 600 D with Weber carburetors operated at idle. At the start of the experiment the fuel-air mixture was adjusted so that the exhaust gas between 3.7 and Contained 4.4 percent by volume carbon monoxide.

The cooling water temperature was kept at 47 tloc. The one used Fuel was an unstabilized gasoline with a Pb content of 0.4 g / l and contained Cracked gasoline parts.

In the tests with the aforementioned fuel, after about 15 Test hours an increase in the CO content in the exhaust gas, which is due to the dirt deposits in the carburetor. Maximum values were up to 7.1 percent by volume CO measured after 50 hours of testing.

However, 100 ppm were cyclohexane hexacarboxylic acid tri-tridecylimide or -tri-n-nonylimide mixed with the fuel and the engine under otherwise identical conditions driven, even after 100 hours of operation there was no increase in the CO content to be established. The inlet valves were also clean.

Application example 3 Two 2.5 l class trolleys of the same type and of the same make and approximately the same mileage (t 8000 km) were each with the same premium gasoline and the same lubricating oil in the taxi operation at the same time in the same City driven. The vehicles had a mileage of 76,000 and 83,000 respectively km and were, especially the engine, in perfect technical condition.

It turned out that the first vehicle, the one with an additional free Fuel was operated, after 15,000 kilometers no reduction in the usual black deposits in the carburetor and in the mixture intake system could.

However, cyclohexane hexanecarboxylic acid hexa- (di-2-ethylhexyl) amide was used added in an amount of 70 ppm or 100 ppm to the fuel of the second vehicle, after 3000 kilometers the carburetor parts already showed a significant decrease the pollution that has already formed. After about another 5000 kilometers was the dirt on the walls of the carburetor has almost disappeared. The inlet valves were clean.

Application Example 4 A Fiat engine was used on an engine test bench Type 500 D operated with Weber carburettors in idle. At the start of the experiment, that was The fuel-air mixture is regulated so that the exhaust gas is between 3.6 and 4.4 percent by volume Contained carbon monoxide.

The cooling water temperature was kept at 47 t10C. The one used Fuel was a stabilized gasoline with a Pb content of 0.4 g / l and contained Cracked gasoline parts.

In the tests with the aforementioned fuel, after about 15 Attempt to increase the CO content in the exhaust gas, which is due to the dirt deposits in the carburetor. Maximum values were up to 7.0 percent by volume CO measured after 50 hours of testing.

However, 100 ppm bicyclooctentetracarboxylic acid di-benzyltmide were used mixed with the fuel and the engine driven under otherwise identical conditions, no increase in the CO content was found even after 72 hours of operation will. The inlet valves were also clean.

Claims (1)

Claims 1. Modification of the use of ester amides of cyclic polycarboxylic acids of the formula in which A is the hydrocarbon radical of a mono-, bi- or tricyclic non-aromatic polycarboxylic acid with m + n carboxyl groups, R1 is the radical of an alcohol with 5 to 18 carbon atoms, R2-NR) is the radical of an aliphatic, cycloaliphatic or aromatic primary or secondary amine 2 to 56 carbon atoms and m and n denote the numbers 1 to 5, the sum of m + n being 5 to 6 and at least one of the ester or amide radicals being derived from alcohols or amines having at least 6 carbon atoms, as an additive to Fuels for gasoline engines according to the main patent. (Patent application P 22 56 690.1-42), characterized in that compounds of the formula II are used in which A is the hydrocarbon residue of a mono-, bi- or tricyclic non-aromatic polycarboxylic acid with m + n + 1 carboxyl groups, R is the residue of an alcohol with 5 to 18 carbon atoms, the rest of a primary and the radical of a primary or secondary amine, m the numbers 0 to 4, n the numbers 0 to 6, 1 the numbers 0, 2, 4 or 6, where the sum of m, n and 1 is 3 to 6 and where at least one of the ester, amide or imide radicals is derived from alcohols or amines with at least 6 carbon atoms and furthermore 1 being a number greater than 0 if m is greater than 0 2. Use of compounds according to claim 1, the alcohol component of which is an alkanol having 4 to 18 carbon atoms. 5. Use of compounds according to claim 1 in amounts of 10 to 1000 ppm, preferably 50 to 300 ppm, based on the fuel.