Method of reducing the vapor pressure of ethanol-containing motor fuels for spark ignition combustion engines

Abstract

Method of reducing the pressure of a C 3 to C 12 hydrocarbon-based motor fuel mixture containing 0.1 to 20% by volume of ethanol for conventional spark ignition internal combustion engines, wherein, in addition to an ethanol component (b) and a C 3 to C 12 hydrocarbon component (a), an oxygen-containing additive (c) selected from at least one of the following types of compounds: alcohol other than ethanol, ketone, ether, ester, hydroxy ketone, ketone ester, and a heterocyclic-containing oxygen compound, is used in the fuel mixture in an amount of at least 0.05 by volume of the total fuel, is disclosed. A mixture of fuel grade ethanol (b) and oxygen-containing additive (c) usable in the method of the invention is also disclosed.

What is claimed is:  
     
         1 . A method for providing a hydrocarbon-based motor fuel composition for conventional spark ignition internal combustion engines having a reduced vapor pressure comprising combining: 
 (a) a hydrocarbon component comprising C 3  to C 12  hydrocarbon fractions;    (b) an ethanol component comprising fuel grade ethanol for conventional spark ignition internal combustion engines, said ethanol component comprising 0.1% to 20% of the composition by volume; and    (c) an oxygen-containing additive comprising at least one compound selected from the group consisting of alcohol other than ethanol, ketone, ether, ester, hydroxyketone, ketone ester and a heterocyclic compound containing oxygen, said oxygen-containing additive comprising at least 0.05% of the composition by volume.    
     
     
         2 . The method according to    claim 1   , wherein the oxygen-containing additive (c) is added to the ethanol component (b) and then a mixture of (b) and (c) is added to the hydrocarbon component (a).  
     
     
         3 . The method according to    claim 1   , wherein the ethanol component (b) is added to the hydrocarbon component (a) and then the oxygen-containing additive (c) is combined with a mixture of (b) and (a).  
     
     
         4 . A method according to any one of claims  1 - 3 , wherein the oxygen-containing additive (c) is at least one compound selected from the group consisting of (1) an alkanol having from 3 to 10 carbon atoms; (2) a ketone having from 4 to 9 carbon atoms; (3) a dialkyl ether having from 6 to 10 carbon atoms; (4) an alkyl ester of an alkanoic acid, said alkyl ester having 5 to 8 carbon atoms; (5) a hydroxyketone having 4 to 6 carbon atoms; (6) a ketone ester of an alkanoic acid, said ketone ester having 5 to 8 carbon atoms; and (7) an oxygen-containing heterocyclic compound having 5 to 8 carbon atoms.  
     
     
         5 . A method according to any one of claims  1 - 3 , wherein the hydrocarbon component (a) is a non-reformulated standard gasoline, a hydrocarbon liquid from petroleum refining, a hydrocarbon liquid from natural gas, a hydrocarbon liquid from an off-gas of chemical-recovery carbonization, a hydrocarbon liquid from synthesis gas processing or mixtures thereof.  
     
     
         6 . A method according to any one of claims  1 - 3 , wherein a denatured ethanol mixture comprising about 92% by volume of ethanol and about 8% by volume of hydrocarbons and by-products is present in the motor fuel composition.  
     
     
         7 . A method according to any one of claims  1 - 3 , wherein the ethanol component (b) comprises at least about by volume 99.5% of ethanol.  
     
     
         8 . A method according to any one of claims  1 - 3 , wherein the components (a), (b) and (c) are combined without being mixed and the resulting motor fuel composition is permitted to stand for at least one hour prior to use.  
     
     
         9 . A method according to any one of claims  1 - 3 , wherein the oxygen-containing additive (c) is present in amounts up to 15% by volume of the motor fuel composition.  
     
     
         10 . A method according to any one of claims  1 - 3 , wherein the motor fuel composition exhibits the following characteristics: 
 (i) a density at 15° C., according to ASTM D-4059 of at least 690 kg /m 3 ;    (ii) an oxygen content according to ASTM D-4815 of no greater than 7% w/w;    (iii) a dry vapor pressure equivalent according to ASTM D-5191 from 20 kPa to 120 kPa;    (iv) an acids content according to ASTM D-1613 of no greater than 0.1 weight % HAc;    (v) a pH according to ASTM D-1287 from 5 to 9;    (vi) an aromatics content according to SS 155120 of no greater than 40% by volume, wherein benzene is present in amounts according to EN 238 no greater than 1% by volume;    (vii) a sulfur content according to ASTM D-5453 of no greater than 50 mg/kg;    (viii) a gum content according to ASTM D-381 of no greater than 2 mg/100 ml;    (ix) a water content according to ASTM D-6304 of no greater than 0.25% w/w;    (x) distillation properties according to ASTM D-86, wherein initial boiling point is at least 20° C.; a vaporizable portion at 70° C. is at least 25% by volume; a vaporizable portion at 100° C. is at least 50% by volume; a vaporizable portion at 150° C. is at least 75% by volume; a vaporizable portion at 190° C. is at least 95% by volume; a final boiling point no greater than 205° C.; and an evaporation residue no greater than 2% by volume; and    (xi) an anti-knock index 0.5 (RON+MON) according to ASTM D-2699-86 and ASTM D-2700-86 of at least 80.    
     
     
         11 . A method according to any one of claims  1 - 3 , wherein vapor pressure increase induced by the ethanol component (b) is reduced by at least 50%.  
     
     
         12 . The method according to    claim 11   , wherein vapor pressure increase induced by the ethanol component (b) is reduced by at least 80%.  
     
     
         13 . The method according to    claim 12   , wherein vapor pressure increase induced by the ethanol component (b) is reduced by 100%.  
     
     
         14 . A motor fuel composition for a conventional spark ignition internal combustion engine comprising: 
 (a) a hydrocarbon component comprising C 3 -C 12  hydrocarbon fractions;    (b) a fuel grade ethanol comprising 0.1% to 20% of a total volume of the motor fuel composition; and    (c) an oxygen-containing additive comprising at least one of (1) an alkanol having from 3 to 10 carbon atoms; (2) a ketone having from 4 to 9 carbon atoms; (3) a dialkyl ether having from 6 to 10 carbon atoms; (4) an alkyl ester of an alkanoic acid, said alkyl ester having 5 to 8 carbon atoms; (5) a hydroxyketone having 4 to 6 carbon atoms; (6) a ketone ester of an alkanoic acid, said ketone ester having 5 to 8 carbon atoms or (7) an oxygen-containing heterocyclic compound having 5 to 8 carbon atoms, and said oxygen-containing additive comprises 0.05% to 15% of the total volume of the motor fuel composition.    
     
     
         15 . The composition according to    claim 14   , wherein said fuel grade ethanol (b) comprises 1% to 20% of the total volume of the motor fuel composition.  
     
     
         16 . The composition according to    claim 14   , wherein wherein said fuel grade ethanol (b) comprises 3% to 15% of the total volume of the motor fuel composition.  
     
     
         17 . The composition according to    claim 14   , wherein wherein said fuel grade ethanol (b) comprises 5% to 10% of the total volume of the motor fuel composition.  
     
     
         18 . The composition according to    claim 14   , wherein said oxygen-containing additive (c) comprises 0.1% to 15% of the total volume of the motor fuel composition.  
     
     
         19 . The composition according to    claim 14   , wherein said oxygen-containing additive (c) comprises 3% to 10% of the total volume of the motor fuel composition.  
     
     
         20 . The composition according to    claim 14   , wherein said oxygen-containing additive (c) comprises 5% to 10% of the total volume of the motor fuel composition.  
     
     
         21 . A mixture utilized in preparation of a motor fuel composition comprising: 
 (i) a fuel grade ethanol (b) and    (ii) an oxygen-containing additive (c) comprising at least one of (1) an alkanol having from 3 to 10 carbon atoms; (2) a ketone having from 4 to 9 carbon atoms; (3) a dialkyl ether having from 6 to 10 carbon atoms; (4) an alkyl ester of an alkanoic acid, said alkyl ester having 5 to 8 carbon atoms; (5) a hydroxyketone having 4 to 6 carbon atoms; (6) a ketone ester of an alkanoic acid, said ketone ester having 5 to 8 carbon atoms or (7) an oxygen-containing heterocyclic compound having 5 to 8 carbon atoms, wherein a ratio of (b) to (c) is from 1:150 to 400:1 by volume.    
     
     
         22 . The mixture according to    claim 21   , wherein the ratio of (b) to (c) is from 1:10 to 10:1 by volume.  
     
     
         23 . A mixture utilized in preparation of a motor fuel composition comprising: 
 (i) a fuel grade ethanol (b) in an amount of 0.5% to 99.5% by volume;    (ii) an oxygen-containing additive (c) in an amount of 0.5% to 99.5% by volume, said oxygen-containing additive (c) comprising at least one of (1) an alkanol having from 3 to 10 carbon atoms; (2) a ketone having from 4 to 9 carbon atoms; (3) a dialkyl ether having from 6 to 10 carbon atoms; (4) an alkyl ester of an alkanoic acid, said alkyl ester having 5 to 8 carbon atoms; (5) a hydroxyketone having 4 to 6 carbon atoms; (6) a ketone ester of an alkanoic acid, said ketone ester having 5 to 8 carbon atoms or (7) an oxygen-containing heterocyclic compound having 5 to 8 carbon atoms; and    (iii) at least one C 5 -C 12  hydrocarbon as a component (d) in an amount of up to 99% by volume,    wherein the ratio between the components in the mixture (b)/{(c)+(d)} is from 1:200 up to 200:1.    
     
     
         24 . The mixture according to    claim 23   , wherein said component (d) is at least one C 8 -C 11  hydrocarbon.  
     
     
         25 . The mixture according to    claim 23   , including up to 90% by volume of said component (d).  
     
     
         26 . The mixture according to    claim 23   , including up to 79.5% by volume of said component (d).  
     
     
         27 . The mixture according to    claim 23   , comprising from 5% to 77% by volume of said component (d).  
     
     
         28 . The mixture according to    claim 23   , comprising 9.5% to 99% by volume of said component (b).  
     
     
         29 . The mixture according to    claim 23   , comprising 20% to 95% by volume of said component (b).  
     
     
         30 . The mixture according to    claim 23   , comprising 25% to 92% by volume of said component (b).  
     
     
         31 . The mixture according to    claim 23   , comprising 0.5% to 90% by volume of said component (c).  
     
     
         32 . The mixture according to    claim 23   , comprising 0.5% to 80% by volume of said component (c).  
     
     
         33 . The mixture according to    claim 23   , comprising 3% to 70% by volume of said component (c).  
     
     
         34 . The mixture according to    claim 23   , wherein the ratio between the components in the mixture (b)/{(c)+(d)} is from 1:10 up to 10:1.  
     
     
         35 . The mixture of    claim 23   , wherein said component (d) is at least one of a saturated aliphatic hydrocarbon, unsaturated aliphatic hydrocarbon, alicyclic saturated hydrocarbon, alicyclic unsaturated hydrocarbon, or a fraction of hydrocarbons boiling at 100-200° C., said fraction of hydrocarbons obtained in distillation of oil, bituminous coal resin or products yielded from processing of synthesis-gas.  
     
     
         36 . The mixture according to    claim 21   , wherein a denatured ethanol mixture comprising about 92% by volume of ethanol and about 8% by volume of hydrocarbons and by-products is present.  
     
     
         37 . The mixture according to    claim 21   , wherein said fuel grade ethanol (b) comprises at least about 99.5% by volume of ethanol.  
     
     
         38 . The mixture according to    claim 23   , wherein a denatured ethanol mixture comprising about 92% by volume of ethanol and about 8% by volume of hydrocarbons and by-products is present.  
     
     
         39 . The mixture according to    claim 23   , wherein said fuel grade ethanol (b) comprises at least about 99.5% by volume of ethanol.  
     
     
         40 . A method of making a fuel for use in a conventional spark ignition internal combustion engine comprising combining a sufficient amount of the mixture according to any one of claims  21 - 39  with a conventional gasoline fuel to provide a vapor pressure of the combination that is no greater than the vapor pressure of the conventional gasoline fuel.  
     
     
         41 . A fuel for use in a conventional spark ignition internal combustion engine made according to the method of    claim 40   .  
     
     
         42 . The fuel according to    claim 41   , wherein an octane number of the combination is at least the same as that of the conventional gasoline fuel.  
     
     
         43 . The fuel according to    claim 41   , wherein an octane number of the combination meets mandatory regulation limits for octane numbers.  
     
     
         44 . A fuel for use in a modified gasoline engine comprising: 
 (i) a fuel grade ethanol (b) and    (ii) an oxygen-containing additive (c) comprising at least one of (1) an alkanol having from 3 to 10 carbon atoms; (2) a ketone having from 4 to 9 carbon atoms; (3) a dialkyl ether having from 6 to 10 carbon atoms; (4) an alkyl ester of an alkanoic acid, said alkyl ester having 5 to 8 carbon atoms; (5) a hydroxyketone having 4 to 6 carbon atoms; (6) a ketone ester of an alkanoic acid, said ketone ester having 5 to 8 carbon atoms or (7) an oxygen-containing heterocyclic compound having 5 to 8 carbon atoms, wherein a ratio of (b) to (c) is from 1:150 to 400:1 by volume.    
     
     
         45 . A fuel for use in a modified gasoline engine comprising: 
 (i) a fuel grade ethanol (b) in an amount of 0.5% to 99.5% by volume;    (ii) an oxygen-containing additive (c) in an amount of 0.5% to 99.5% by volume, said oxygen-containing additive (c) comprising at least one of (1) an alkanol having from 3 to 10 carbon atoms; (2) a ketone having from 4 to 9 carbon atoms; (3) a dialkyl ether having from 6 to 10 carbon atoms; (4) an alkyl ester of an alkanoic acid, said alkyl ester having 5 to 8 carbon atoms; (5) a hydroxyketone having 4 to 6 carbon atoms; (6) a ketone ester of an alkanoic acid, said ketone ester having 5 to 8 carbon atoms or (7) an oxygen-containing heterocyclic compound having 5 to 8 carbon atoms; and    (iii) at least one C 5 -C 12  hydrocarbon as a component (d) in an amount of up to 99% by volume,    wherein the ratio between the components in the mixture (b)/{(c)+(d)} is from 1:200 up to 200:1.