High-power liquid fuel composition for spark-ignition engines

Abstract

A high-power liquid fuel composition for spark-ignition engines is provided. The fuel composition has a RON greater than or equal to 95 and a MON greater than or equal to 85, the RON and MON values being measured according to the ASTM D 2699-86 standard or D 2700-86 standard, and includes at least one C4-C5 unsaturated alcohol. The disclosure also relates to the use of a C4-C5 unsaturated alcohol, preferably 3-methyl-2-butene-1-ol or 3-methyl-3-butene-1-ol, in a petrol fuel composition, for improving the power of a naturally-aspirated or turbocharged spark-ignition engine, during the combustion. The disclosure also relates to a process for preparing such a fuel composition.

1 . A method for improving the power of a naturally-aspirated or turbocharged spark-ignition engine during combustion of a petrol fuel composition, the method comprising adding at least one C4-C5 unsaturated alcohol in the petrol fuel composition. 
     
     
         2 . The method according to  claim 1 , wherein the power improvement is at least 2 hp for engine speeds ranging from 3000 to 8250 rpm. 
     
     
         3 . The method according to  claim 1 , wherein the petrol fuel composition is a competition fuel composition. 
     
     
         4 . The method according to  claim 1 , comprising improving the power of a turbocharged engine. 
     
     
         5 . The method according to  claim 1 , wherein the petrol fuel composition has a RON greater than or equal to 95 and a MON greater than or equal to 85, the RON and MON values being measured according to the ASTM D 2699-86 standard or D 2700-86 standard. 
     
     
         6 . The method according to  claim 1 , wherein the C4-C5 unsaturated alcohol is selected from 3-methyl-2-butene-1-ol, 3-methyl-3-butene-1-ol and their mixture. 
     
     
         7 . The method according to  claim 1  wherein the composition comprises a single C4-C5 unsaturated alcohol. 
     
     
         8 . The method according to  claim 1 , wherein the composition has:
 a density measured according to the ASTM D 4052 standard comprised between 720 and 785 kg/m 3 ;   a maximum oxygen content less than 2.8% by mass or less than 3.7% by mass if the lead content is less than 0.013 g/L;   a maximum nitrogen content less than 0.5% by mass;   a benzene content less than 5% by volume, measured according to the ASTM D 3606 standard;   a RON comprised between 97 and 100 and a MON comprised between 86 and 92, measured according to the ASTM D 2699-86 standard or D 2700-86 standard, when the lead content of the fuel is non-zero and less than or equal to 0.4 g/L; and   a RON comprised between 95 and 102 and a MON comprised between 85 and 90, measured according to the ASTM D 2699-86 standard or D 2700-86 standard, when the lead content of the fuel is zero or less than 0.4 g/L.   
     
     
         9 . The method according to  claim 1 , wherein the composition comprises moreover one or more additives. 
     
     
         10 . The method according to  claim 1  wherein the composition comprises:
 from 20 to 35% by volume of aromatic hydrocarbons; 
 from 22 to 35% by volume of C6-C9 isoparaffins; 
 from 5 to 15% by volume of C4-C5 isoparaffins; 
 from 14 to 50% by volume of one or more C4-C5 diolefins; 
 from 3 to 22% by volume, 
 from 0 to 6% by volume of one or more C1-C4 paraffinic or isoparaffinic alcohols; 
 from 0 to 5% by volume of at least one alkyl ether; and 
 from 0 to 6% by volume of one or more C8 isoolefins. 
 
     
     
         11 . The method according to  claim 1 , wherein the composition comprises:
 from 20 to 35% by volume of aromatic hydrocarbons;   from 22 to 35% by volume of isooctane;   from 5 to 15% by volume of isopentane;   from 14 to 50% by volume of isoprene;   from 3 to 22% by volume of at least one C4-C5 unsaturated alcohol;   from 3 to 6% by volume of one or more C1-C4 paraffinic or isoparaffinic alcohols; and   from 3 to 6% by volume of one or more C8 isoolefins.   
     
     
         12 . The method according to  claim 11 , wherein the sum of the percentages by volume of the constituents of the composition is equal to 100%. 
     
     
         13 . The method according to  claim 1 , wherein the composition comprises from 5 to 15% by volume of at least one C4-C5 unsaturated alcohol. 
     
     
         14 . The method according to  claim 7 , wherein the composition comprises a single C4-C5 unsaturated alcohol chosen from 3-methyl-2-butene-1-ol or 3-methyl-3-butene-1-ol. 
     
     
         15 . The method according to  claim 10 , wherein aromatic hydrocarbons are selected from the alkylbenzenes. 
     
     
         16 . The method according to  claim 10 , wherein the C4-C5 diolefins have two conjugated ethylene bonds. 
     
     
         17 . The method according to  claim 13 , wherein the composition comprises from 5 to 15% by volume of 3-methyl-2-butene-1-ol.