Use of an alkoxylated polytetrahydrofuran to reduce fuel consumption

Abstract

The use of an alkoxylated polytetrahydrofurane of formula wherein m, m, n, n, p, p and k are integers in the range of ?1, R.sup.1 denotes an unsubstituted linear or branched alkyl radical, R.sup.2 denotes CH.sub.2CH.sub.3, and R.sup.3 denotes a hydrogen atom or CH.sub.3, as an additive in a fuel for reducing fuel consumption in the operation of an internal combustion engine with this fuel. ##STR00001##

Claims

1. A method for reducing fuel consumption in operating an internal combustion engine with a fuel, the method comprising: introducing an alkoxylated polytetrahydrofurane of formula (I) ##STR00012## into the fuel as an additive, wherein m is an integer in the range of ?1 to ?50, m is an integer in the range of ?1 to ?50, (m+m) is an integer in the range of ?2 to ?90, n is an integer in the range of ?0 to ?75, n is an integer in the range of ?0 to ?75, p is an integer in the range of ?0 to ?75, p is an integer in the range of ?0 to ?75, k is an integer in the range of ?2 to ?30, R.sup.1 denotes an unsubstituted, linear or branched, alkyl radical having 6, 7, 8, 9, 10, 11, 12, 13, 14 15, 16, 17, 18, 19 20, 21 22, 23, 24, 25, 26, 27 or 28 carbon atoms, R.sup.2 denotes CH.sub.2CH.sub.3, and R.sup.3 denotes a hydrogen atom, whereby the concatenations denoted by k are distributed to form a block polymeric structure and the concatenations denoted by p, p, n, n, m and m are distributed to form a block polymeric structure.

2. The method as described in claim 1, wherein the additive minimizes power loss in the internal combustion engine and improves acceleration of the internal combustion engine.

3. The method as described in claim 1, wherein the additive improves the lubricity of lubricant oils contained in the internal combustion engine for lubricating purposes by operating the internal combustion engine with the fuel containing an effective amount of at least one alkoxylated polytetrahydrofurane of formula (I).

4. The method according to claim 1, wherein k is an integer in the range of ?3 to ?25.

5. The method according to claim 1, wherein the alkoxylated polytetrahydrofurane has a weight average molecular weight Mw in the range of 500 to 20000 g/mol determined according to DIN 55672-1 (polystyrene calibration standard).

6. The method according to claim 1, wherein (m+m) is in the range of ?3 to ?65.

7. The method according to claim 1 wherein the ratio of (m+m) to k is in the range of 0.3:1 to 6:1.

8. The method according to claim 1, wherein m is an integer in the range of ?1 to ?25 and m is an integer in the range of ?1 to ?25.

9. The method according to claim 1, wherein R.sup.1 denotes an unsubstituted, linear alkyl radical having 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17 or 18 carbon atoms.

10. The method according to claim 1, wherein m is an integer in the range of ?1 to ?30, m is an integer in the range of ?1 to ?30, (m+m) is an integer in the range of ?3 to ?50, n is an integer in the range of ?3 to ?45, n is an integer in the range of ?3 to ?45, (n+n) is an integer in the range of ?6 to ?90, p is an integer in the range of ?0 to ?75, p is an integer in the range of ?0 to ?75, k is an integer in the range of ?3 to ?25, R.sup.1 denotes an unsubstituted, linear or branched, alkyl radical having 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17 or 18 carbon atoms, R.sup.2 denotes CH.sub.2CH.sub.3, and R.sup.3 denotes a hydrogen atom.

11. The method according to claim 10, wherein the ratio of (m+m) to k is in the range of 0.3:1 to 6:1 and the ratio of (n+n) to k is in the range of 1.5:1 to 10:1.

12. The method according to claim 1, wherein m is an integer in the range of ?1 to ?30, m is an integer in the range of ?1 to ?30, (m+m) is an integer in the range of ?3 to ?50, n is an integer in the range of ?0 to ?45, n is an integer in the range of ?0 to ?45, p is an integer in the range of ?3 to ?45, p is an integer in the range of ?3 to ?45, (p+p) is an integer in the range of ?6 to ?90, k is an integer in the range of ?3 to ?25, R.sup.1 denotes an unsubstituted, linear or branched, alkyl radical having 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17 or 18 carbon atoms, R.sup.2 denotes CH.sub.2CH.sub.3, and R.sup.3 denotes a hydrogen atom.

13. The method according to claim 12, wherein the ratio of (m+m) to k is in the range of 0.3:1 to 6:1 and the ratio of (p+p) to k is in the range of 1.5:1 to 10:1.

14. A fuel composition comprising, in a major amount, a gasoline fuel and, in a minor amount, at least one alkoxylated polytetrahydrofurane of formula (I), and at least one fuel additive which is different from the alkoxylated polytetrahydrofurane (I) and has detergent action, ##STR00013## wherein m is an integer in the range of ?1 to ?50, m is an integer in the range of ?1 to ?50, (m+m) is an integer in the range of ?2 to ?90, n is an integer in the range of ?0 to ?75, n is an integer in the range of ?0 to ?75, p is an integer in the range of ?0 to ?75, p is an integer in the range of ?0 to ?75, k is an integer in the range of ?2 to ?30, R.sup.1 denotes an unsubstituted, linear or branched, alkyl radical having 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27 or 28 carbon atoms, R.sup.2 denotes CH.sub.2CH.sub.3, and R.sup.3 denotes a hydrogen atom, whereby the concatenations denoted by k are distributed to form a block polymeric structure and the concatenations denoted by p, p, n, n, m and m are distributed to form a block polymeric structure.

15. The fuel composition according to claim 14 comprising, as the fuel additive which is different from the alkoxylated polytetrahydrofuran (I) and has detergent action, at least one representative (D) selected from the group consisting of: (Da) a mono- or polyamino group having up to 6 nitrogen atoms, at least one nitrogen atom having basic properties; (Db) a nitro group, optionally in combination with at least one hydroxyl group; (Dc) a hydroxyl group in combination with at least one mono- or polyamino group, at least one nitrogen atom having basic properties; (Dd) a carboxyl group or an alkali metal or an alkaline earth metal salt thereof; (De) a sulfonic acid group or an alkali metal or an alkaline earth metal salt thereof; (Df) a polyoxy-C.sub.2-C.sub.4-alkylene moiety terminated by at least one hydroxyl group, at least one mono- or polyamino group, at least one nitrogen atom having basic properties, or by at least one carbamate group; (Dg) a carboxylic ester group; (Dh) a moiety derived from succinic anhydride and having at least one hydroxyl and/or amino and/or amido and/or imido group; and/or (Di) a moiety obtained by Mannich reaction of at least one substituted phenol with at least one aldehyde and at least one mono- or polyamine.

16. The fuel composition according to claim 14, additionally comprising, as a further fuel additive in a minor amount, at least one carrier oil.

17. The fuel composition according to claim 14, additionally comprising, as a further fuel additive in a minor amount, at least one tertiary hydrocarbyl amine of formula NR.sup.4R.sup.5R.sup.6 wherein R.sup.4, R.sup.5 and R.sup.6 are the same or different C.sub.1- to C.sub.20-hydrocarbyl residues with the proviso that the overall number of carbon atoms in formula (I) does not exceed 30.

18. The fuel composition according to claim 15, comprising at least one representative (D) which is (Da), which is a polyisobutene monoamine or a polyisobutene polyamine having M.sub.n=300 to 5000, having at least 50 mol-% of vinylidene double bonds and having been prepared by hydroformylation of the respective polyisobutene and subsequent reductive amination with ammonia, monoamines or polyamines, in combination with at least one mineral or synthetic carrier oil.

19. An additive concentrate, comprising at least one alkoxylated polytetrahydrofurane of formula (I), and at least one fuel additive which is different from the alkoxylated polytetrahydrofurane (I) and has detergent action, ##STR00014## wherein m is an integer in the range of ?1 to ?50, m is an integer in the range of ?1 to ?50, (m+m) is an integer in the range of ?2 to ?90, n is an integer in the range of ?0 to ?75, n is an integer in the range of ?0 to ?75, p is an integer in the range of ?0 to ?75, p is an integer in the range of ?0 to ?75, k is an integer in the range of ?2 to ?30, R.sup.1 denotes an unsubstituted, linear or branched, alkyl radical having 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25 26, 27 or 28 carbon atoms, R.sup.2 denotes CH.sub.2CH.sub.3, and R.sup.3 denotes a hydrogen atom, whereby the concatenations denoted by k are distributed to form a block polymeric structure and the concatenations denoted by p, p, n, n, m and m are distributed to form a block polymeric structure.

20. The additive concentrate according to claim 19, comprising at least one representative (Da), which is a polyisobutene monoamine or polyisobutene polyamine having M.sub.n=300 to 5000, having at least 50 mol-% of vinylidene double bonds and having been prepared by hydroformylation of the respective polyisobutene and subsequent reductive amination with ammonia, monoamines or polyamines, and further comprising at least one mineral or synthetic carrier oil.

Description

EXAMPLES

Example 1: Preparation of an Alkoxylated Polytetrahydrofurane from Polytetrahydrofurane 650 with 12 Equivalents of C12-Epoxide and 20 Equivalents of Butylene Oxide (Block)

(1) A steel reactor (1.5 l) was loaded with polytetrahydrofurane (MW 250) (0.2 mol, 130 g), and 3.4 g KOtBu was mixed and the reactor was purged with nitrogen. The reactor was heated under vacuum (10 mbar) and heated to 140? C. for 0.25 h. Then again nitrogen was loaded. At a pressure of 2 bar 50 g C.sub.12-epoxide was brought in dropwise at 140? C. 390 g C.sub.12-epoxide of total (441 g; 2.4 mol) was added during 5 h at 140? C. and under pressure of 6 bar. Then butylene oxide (288 g, 4.0 mol) was added within 4 h at 140? C. The reactor was stirred for 10 h at 140? C. and cooled to 80? C. The product was stripped by nitrogen. Then the product was discharged and mixed with Ambosol? (magnesium silicate, 30 g) and mixed on a rotary evaporator at 80? C. The purified product was obtained by filtration in a pressure strainer (Filtrations media: Seitz 900). Yield: 866 g, quantitative (theor.: 859 g) OHZ: 30.1 mg KOH/g.

Example 2: Preparation of a Gasoline Performance Package

(2) 400 mg/kg of the alkoxylated polytetrahydrofurane of Example 1 above were mixed with a gasoline performance package comprising the customary detergent additive Kerocom? PIBA (a polyisobutene monoamine made by BASF SE, based on a poly-isobutene with M.sub.n=1000), a customary polyether-based carrier oil, kerosene as a diluent and a customary corrosion inhibitor in customary amounts.

Example 3: Fuel Economy Tests

(3) A typical Eurosuper base fuel to EN 228 customary on the European market was additized with the gasoline performance package of Example 2 in the dosage rate specified there and used to determine fuel economy in a fleet test with three different automobiles according to U.S. Environmental Protection Agency Test Protocol, C.F.R. Title 40, Part 600, Subpart B. For each automobile, the fuel consumption was determined first with unadditized fuel and then with the same fuel which now, however, comprised the gasoline performance package of Example 2 in the dosage specified there. The following fuel savings were achieved: 2004 Mazda 3, 2.0 L 14: 2.00%; Honda Civic, 1.8 L 14: 0.95%; 2010 Chevy HRR, 2.2 L 14: 0.66%
On average, over all automobiles used, the result was an average fuel saving of 1.20%.

Example 4: Engine Cleanliness Tests

(4) In order to demonstrate that the alkoxylated polytetrahydrofuranes (I) mentioned do not decrease engine cleanliness, the average IVD values and the TCD values were determined with gasoline performance package of Example 2 (GPP 1) and, for comparison, with the same gasoline performance package without the alkoxylated polytetra-hydrofurane of Example 1 (GPP 2), according to CEC F-20-98 with a Mercedes Benz M111 E engine using a customary RON 95 E10 gasoline fuel and a customary RL-223/5 engine oil. The following table shows the results of the determinations:

(5) TABLE-US-00001 Additive average IVD [mg/valve] TCD [mg] None 118 2852 GPP 1 3 4582 GPP 2 12 4433

Example 5: Storage Stability

(6) 48.0% by weight of GPP 2 above were mixed with 14.3% by weight of alkoxylated polytetrahydrofurane of Example 1 and 37.7% by weight of xylene at 20? C. and stored thereafter in a sealed glass bottle at ?20? C. for 42 days. At the beginning of this storage period and then after each 7 days, the mixture was evaluated visually and checked for possible phase separation and precipitation. It is the aim that the mixture remains clear (c), homogeneous (h) and liquid (l) after storage and does not exhibit any phase separation (ps) or precipitation (pr). The following table shows the results of the evaluations:

(7) TABLE-US-00002 after 7 days c, h, l after 14 days c, h, l after 21 days c, h, l after 28 days c, h, l after 35 days c, h, l after 42 days c, h, l Result: pass