Fuel Composition

Abstract

A fuel composition includes a lower alkyl monool(s) and C 2 -C 6 esters of one or more long chain fatty acids. Generally, C, H and O atoms constitute at least 99.99% (by wt.) of the composition, and the composition can be essentially free of sulfur and/or nitrogen atoms. The composition can be provided by adjusting to less than 7.0 the pH of a liquid that contains at least one C 2 -C 6 ester of one or more long chain fatty acids. The C 2 -C 6 ester(s) can be provided by transesterifi-cation of a triglyceride-containing composition using a C 2 -C 6 monool, which preferably is present in stoichiometric excess.

1 . A fuel composition comprising:
 a) at least about 2.5% (by vol.) of at least one C 2 -C 6  alcohol, and   b) at least one C 2 -C 6  ester of one or more long chain fatty acids,   wherein at least one of the following is true:
 (1) said fuel composition exhibits a pH of less than about 6.8, and 
 (2) said fuel composition has a kinematic viscosity of less than about 4.0 centistokes. 
   
     
     
         2 . The fuel composition of  claim 1  wherein said composition exhibits a pH of less than about 6.8 and has a kinematic viscosity of less than about 4.2 centistokes. 
     
     
         3 . The fuel composition of  claim 1  wherein said composition exhibits a pH of from about 5.5 to about 6.7. 
     
     
         4 . The fuel composition of  claim 3  wherein said has a kinematic viscosity of less than about 4.2 centistokes. 
     
     
         5 . The fuel composition of  claim 1  wherein said composition comprises at least about 0.2% (by vol.) water. 
     
     
         6 . The fuel composition of  claim 1  wherein said composition has a cloud point of at least as low as −5° C. when measured in accordance with ASTM D2500. 
     
     
         7 . A fuel composition comprising:
 a) from about 5 to about 10% (by vol.) of at least one C 2 -C 6  alcohol, and   b) at least one C 2 -C 6  ester of one or more long chain fatty acids,   said fuel composition having a kinematic viscosity of from about 3.5 to about 4.0 centistokes.   
     
     
         8 . The fuel composition of  claim 7  wherein said composition exhibits a pH of from about 6.0 to about 6.7. 
     
     
         9 . The fuel composition of  claim 7  wherein said composition is essentially free of at least one of sulfur and nitrogen atoms. 
     
     
         10 . The fuel composition of  claim 7  wherein said composition comprises at least about 0.2% (by vol.) water. 
     
     
         11 . The fuel composition of  claim 7  wherein said composition has a cloud point of at least as low as −5° C. when measured in accordance with ASTM D2500. 
     
     
         12 . A process for providing a fuel composition, comprising:
 a) providing a liquid that contains at least one C 2 -C 6  ester of one or more long chain fatty acids,   b) adjusting the pH of said liquid to less than 7.0, thereby providing a raw fuel composition, and   c) optionally, treating said raw fuel composition so as to remove particulates having an average diameter greater than about 1 μm, thereby providing a refined fuel composition.   
     
     
         13 . The process of  claim 12  wherein said at least one C 2 -C 6  ester is provided by transesterifying a triglyceride-containing composition using a C 2 -C 6  monool. 
     
     
         14 . The process of  claim 13  wherein said C 2 -C 6  monool comprises ethanol, said ethanol optionally being present in stoichiometric excess. 
     
     
         15 . The process of  claim 12  wherein said fuel composition comprises at least about 0.2% (by vol.) water. 
     
     
         16 . The process of  claim 12  wherein said fuel composition comprises less than about 5 parts per million of Group I metal ions. 
     
     
         17 - 20 . (canceled)