Fuel composition

Abstract

An unleaded gasoline fuel composition for improving engine performance in spark ignition internal combustion engines comprises: a major amount of gasoline base fuel, and a detergent additive package, wherein the detergent additive package comprises a quaternary ammonium internal salt detergent and a Mannich base detergent mixture, wherein the quaternary ammonium internal salt is obtained from amines or polyamines that is substantially devoid of any free anion species, wherein the Mannich base detergent mixture comprises a first Mannich base detergent component derived from a di- or polyamine and a second Mannich base detergent component derived from a monoamine, wherein the weight ratio of the first Mannich base detergent to the second Mannich base detergent mixture ranges from about 1:6 to about 3:1, and wherein the weight ratio of the quaternary ammonium internal salt detergent and the Mannich base detergent mixture ranges from about 1:10 to about 1:100.

1 . An unleaded gasoline fuel composition for improving engine performance in spark ignition internal combustion engines, wherein the unleaded a gasoline fuel composition comprises:
 a major amount of gasoline base fuel, and   a detergent additive package,   wherein the detergent additive package comprises a quaternary ammonium internal salt detergent and a Mannich base detergent mixture,   wherein the quaternary ammonium internal salt is obtained from amines or polyamines that is substantially devoid of any free anion species,   wherein the Mannich base detergent mixture comprises a first Mannich base detergent component derived from a di- or polyamine and a second Mannich base detergent component derived from a monoamine,   wherein the weight ratio of the first Mannich base detergent to the second Mannich base detergent mixture ranges from about 1:6 to about 3:1, and   wherein the weight ratio of the quaternary ammonium internal salt detergent and the Mannich base detergent mixture ranges from about 1:10 to about 1:100.   
     
     
         2 . The unleaded gasoline fuel composition according to  claim 1  wherein the weight ratio of the first Mannich base detergent to the second Mannich base detergent ranges from about 1:1 to about 1:3. 
     
     
         3 . The unleaded gasoline fuel composition according to  claim 1  wherein the unleaded gasoline fuel composition comprises from about 23 ppm to 2000 ppm by weight of the detergent additive package. 
     
     
         4 . The unleaded gasoline fuel composition according  claim 1  wherein the first Mannich base detergent and the second Mannich base detergent are derived from polyisobutenyl-substituted hydroxyaromatic and wherein the polyisobutenyl group has a molecular weight ranging from 500 to 1000 Daltons, as determined by gel permeation chromatography. 
     
     
         5 . The gasoline fuel additive package according to  claim 4 , wherein the polyisobutenyl-substituted hydroxyaromatic is polyisobutenyl-substituted phenol or cresol. 
     
     
         6 . The gasoline fuel additive package according to  claim 5 , wherein the polyisobutenyl-substituted hydroxyaromatic is polyisobutenyl-substituted cresol. 
     
     
         7 . The unleaded gasoline fuel composition according to  claim 1  wherein the quaternary ammonium internal salt has the structure of Formula II 
       
         
           
           
               
               
           
         
         wherein R and R′ are, independently, alkylene linkers having 1 to 10 carbon atoms; 
         R 8  is a C12 to C100 alkylene, alkene, or hydrocarbyl group or an aryl group or optionally substituted aryl group; each R 9  is, independently, a linear or branched C1 to C4 alkyl group; and R 10  is a hydrogen atom or a C1 to C4 alkyl group. 
       
     
     
         8 . The gasoline fuel additive package according to  claim 1 , wherein the package further comprises one or more of a demulsifier, a corrosion inhibitor, an antiwear additive, an antioxidant, a metal deactivator, an antistatic additive, a dehazer, an antiknock additive, a lubricity additive, a poloyether monool or polyether polyol carrier fluid, and a combustion improver. 
     
     
         9 . Use of an unleaded gasoline fuel composition for improving engine and/or injector performance in a gasoline direct injection engine, wherein the unleaded gasoline fuel composition comprises a major amount of gasoline base fuel and a detergent additive package, wherein the detergent additive package comprises a quaternary ammonium internal salt detergent and a Mannich base detergent mixture, wherein the quaternary ammonium internal salt is obtained from amines or polyamines that is substantially devoid of any free anion species, and wherein the Mannich base detergent mixture comprises a first Mannich base detergent component derived from a di- or polyamine and a second Mannich base detergent component derived from a monoamine, wherein the weight ratio of the first Mannich base detergent to the second Mannich base detergent mixtures ranges from about 1:6 to about 3:1, and wherein the weight ratio of the quaternary ammonium internal salt detergent and the Mannich base detergent mixture ranges from about 1:10 to about 1:100. 
     
     
         10 . Method for improving engine performance and/or injector performance in a gasoline direct injection engine, the method comprising supplying to the engine an unleaded gasoline fuel composition comprising a major amount of gasoline base fuel and a detergent additive package wherein the detergent additive package comprises a quaternary ammonium internal salt detergent and a Mannich base detergent mixture, wherein the quaternary ammonium internal salt is obtained from amines or polyamines that is substantially devoid of any free anion species, and wherein the Mannich base detergent mixture comprises a first Mannich base detergent component derived from a di- or polyamine and a second Mannich base detergent component derived from a monoamine, wherein the weight ratio of the first Mannich base detergent to the second Mannich base detergent mixtures ranges from about 1:6 to about 3:1, and wherein the weight ratio of the quaternary ammonium internal salt detergent and the Mannich base detergent mixture ranges from about 1:10 to about 1:100.