Use of a complex ester to reduce fuel consumption

Abstract

The use of a complex ester obtainable by esterification reaction between aliphatic linear or branched C 2 - to C 12 -dicarboxylic acids, aliphatic linear or branched polyhydroxy alcohols with 3 to 6 hydroxyl groups, and, as chain stopping agents, aliphatic linear or branched C 1 - to C 30 -monocarboxylic acids or aliphatic linear or branched monobasic C 1 - to C 30 -alcohols, as an additive in a fuel for reducing fuel consumption in the operation of an internal combustion engine with this fuel.

1 . A process for reducing fuel consumption in the operation of an internal combustion engine, the process comprising operating an internal combustion engine with a fuel comprising an additive comprising a complex ester obtained by an esterification reaction among
 (A) at least one aliphatic linear or branched C 2 - to C 12 -dicarboxylic acid,   (B) at least one aliphatic linear or branched polyhydroxy alcohol having 3 to 6 hydroxyl groups, and   (C) as a chain stopping agent
 (C1) at least one aliphatic linear or branched C 1 - to C 30 -monocarboxylic acid in case of an excess of component (B), or 
 (C2) at least one aliphatic linear or branched monobasic C 1 - to C 30 -alcohol in case of an excess of component (A). 
   
     
     
         2 . The process of  claim 1 , which reduces power loss in the internal combustion engine, and which improves acceleration of the internal combustion engine. 
     
     
         3 . The process of  claim 1 , wherein the additive is present in the fuel in an amount effective to improve a lubricity of a lubricant oil in the internal combustion engine. 
     
     
         4 . The process of  claim 1 , wherein component (A) comprises an aliphatic linear C 6 - to C 10 -dicarboxylic acid. 
     
     
         5 . The process of  claim 1 , wherein component (B) comprises at least one member selected from the group consisting of glycerin, trimethylolpropane and pentaerythritol. 
     
     
         6 . The process of  claim 1 , wherein component (C) comprises an aliphatic linear or branched C 8 - to C 18 -monocarboxylic as (C1), or comprises a linear or branched C 8 - to C 18 -alkanol as (C2). 
     
     
         7 . The process of  claim 1 , wherein the complex ester of comprises from 2 to 9 molecule units of component (A) and comprises from 3 to 10 molecule units of component (B), wherein component (B) is in excess compared to component (A), and remaining free hydroxyl groups of (B) are completely or partly capped with a corresponding number of molecule units of component (C1). 
     
     
         8 . The process of  claim 1 , wherein the complex ester comprises from 3 to 10 molecule units of component (A) and comprises from 2 to 9 molecule units of component (B), wherein component (A) is in excess compared to component (B), and remaining free carboxyl groups of (A) are completely or partly capped with a corresponding number of molecule units of component (C2). 
     
     
         9 . A fuel composition comprising:
 in a major amount, a gasoline fuel;   in a minor amount, at least one complex ester obtained by an esterification reaction among   (A) at least one aliphatic linear or branched C 2 - to C 12 -dicarboxylic acid,   (B) at least one aliphatic linear or branched polyhydroxy alcohol having 3 to 6 hydroxyl groups, and   (C) as a chain stopping agent
 (C1) at least one aliphatic linear or branched C 1 - to C 30 -monocarboxylic acid in case of an excess of component (B), or 
 (C2) at least one aliphatic linear or branched monobasic C 1 - to C 30 -alcohol in case of an excess of component (A); and 
   at least one fuel additive which is different from the complex esters ester and has a detergent action.   
     
     
         10 . The fuel composition of  claim 9  comprising as the fuel additive which is different from the complex ester at least one member (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 a hydroxyl group; 
 (Dc) a hydroxyl group in combination with a mono- or polyamino group, at least one nitrogen atom having basic properties; 
 (Dd) a carboxyl group or its alkali metal or alkaline earth metal salt; 
 (De) a sulfonic acid group or its alkali metal or alkaline earth metal salt; 
 (Df) a polyoxy-C 2 -C 4 -alkylene moiety terminated by a hydroxyl group, a mono- or polyamino group, at least one nitrogen atom having basic properties, or by a carbamate group; 
 (Dg) a carboxylic ester group; 
 (Dh) a moiety derived from succinic anhydride and having a hydroxyl and/or an amino and/or an amido and/or an imido group; and 
 (Di) a moiety obtained by Mannich reaction of a substituted phenol with an aldehyde and a mono- or polyamine. 
 
     
     
         11 . The fuel composition of  claim 9 , additionally comprising, as a further fuel additive in a minor amount, at least one carrier oil. 
     
     
         12 . The fuel composition of  claim 9 , additionally comprising, as a further fuel additive in a minor amount, at least one tertiary hydrocarbyl amine of formula NR 1 R 2 R 3  wherein R 1 , R 2  and R 3  are the same or different C 1 - to C 20 -hydrocarbyl residues with the proviso that the overall number of carbon atoms in formula NR 1 R 2 R 3  does not exceed 30. 
     
     
         13 . The fuel composition of  claim 9 , comprising at least one representative (D) that is (Da) a polyisobutene monoamine or a polyisobutene polyamine having M n =300 to 5000, having at least 50 mol-% of vinylidene double bonds and having been prepared by hydroformylation of a respective polyisobutene and subsequent reductive amination with ammonia, a monoamine or a polyamine, in combination with at least one mineral or synthetic carrier oil. 
     
     
         14 . An additive concentrate comprising:
 at least one complex ester obtained by an esterification reaction among   (A) at least one aliphatic linear or branched C 2 - to C 12 -dicarboxylic acid,   (B) at least one aliphatic linear or branched polyhydroxy alcohol having 3 to 6 hydroxyl groups, and   (C) as a chain stopping agent
 (C1) at least one aliphatic linear or branched C 1 - to C 30 -monocarboxylic acid in case of an excess of component (B), or 
 (C2) at least one aliphatic linear or branched monobasic C 1 - to C 30 -alcohol in case of an excess of component (A); and 
   at least one fuel additive which is different from the complex ester and has a detergent action.   
     
     
         15 . The additive concentrate of  claim 14 , comprising at least one representative (D) that is (Da) a polyisobutene monoamine or a polyisobutene polyamine having M n =300 to 5000, having at least 50 mol-% of vinylidene double bonds and having been prepared by hydroformylation of a respective polyisobutene and subsequent reductive amination with ammonia, a monoamine or a polyamine, and further comprising at least one mineral or synthetic carrier oil.