Fuel for homogeneous charge compression ignition (hcci) systems and a process for production of said fuel

Abstract

The invention provides a HCCI fuel or fuel component, which fuel includes at least n-paraffins and iso-paraffins having from 7 to 14 carbon atoms, and which fuel has an ignition delay of less than 7 ms, according to ASTM D6890. A process for preparing a HCCI fuel or fuel component.

1 . A HCCI fuel or fuel component, which fuel includes at least n-paraffins and iso-paraffins having from 7 to 14 carbon atoms, and which fuel has an ignition delay of less than 7 ms, according to ASTM D6890, which fuel has an ASTM D86 distillation range from 90° C. to 270° C. 
   
   
       2 . A fuel as claimed in  claim 1 , which fuel contains less than 1% wt of aromatic and negligible levels of sulphur. 
   
   
       3 . A fuel as claimed in  claim 1 , which fuel has an ignition delay of less than 5 ms. 
   
   
       4 . A fuel as claimed in  claim 1 , which fuel has an ignition delay of between 2 and 5 ms. 
   
   
       5 . A fuel as claimed in  claim 1 , wherein the mass % of the n-paraffins exceeds that of any other single component in the fuel. 
   
   
       6 . A fuel as claimed in  claim 1 , wherein the mass % of the n-paraffins is in excess of 25% by mass of the fuel 
   
   
       7 . A fuel as claimed in  claim 1 , wherein the mass % of the n-paraffins is in excess of 50% by mass of the fuel. 
   
   
       8 . A fuel as claimed in  claim 1 , wherein the mass % of the n-paraffins is in excess of 80% by mass of the fuel. 
   
   
       9 . A fuel as claimed in claim  1 , wherein the mass % of the n-paraffins is in the order of 95% by mass of the fuel. 
   
   
       10 . A fuel as claimed in  claim 1 , wherein the n-paraffins are Fischer-Tropsch (FT) reaction derived n-paraffins. 
   
   
       11 . A fuel as claimed in  claim 1 , wherein the iso-paraffins are FT reaction derived iso-paraffins. 
   
   
       12 . A fuel as claimed in  claim 1 , which fuel includes one or more of: olefins, lubricity improver, and oxygenates. 
   
   
       13 . A fuel as claimed in  claim 1 , which fuel is substantially free of heteroatoms such as nitrogen, sulphur and oxygen. 
   
   
       14 . A process for preparing a fuel, which process includes blending HCCI fuel or fuel component as claimed in  claim 1 , as a blending component with conventional fuel. 
   
   
       15 . A process for preparing a HCCI fuel or fuel component, which fuel or fuel component includes at least n-paraffins and iso-paraffins, which fuel has an ignition delay of less than 7 ms, said process including one or more steps selected from:
 a) hydrotreating at least a Condensate fraction of a Fischer-Tropsch (FT) synthesis reaction product, or a derivative thereof;   b) hydroconverting a Wax fraction of the FT synthesis product or a derivative thereof;   c) fractionating in a single unit or in separate units, one or more of the hydrotreated Condensate fractions of step a) and the hydroconverted fraction of step b) to obtain the desired HCCI fuel or fuel component having from 7 to 14 carbon atoms and which fuel has an ASTM D86 distillation range from 90° C. to 270° C.; and   d) optionally, blending two or more of said components from step c) in a desired ratio to obtain the desired HCCI fuel.   
   
   
       16 . A process as claimed in  claim 15 , wherein the hydroconversion is by way of hydrocracking. 
   
   
       17 . A process as claimed in  claim 15 , wherein the blending of step d) is the blending of FT condensate derivative and hydroconverted FT wax derivative in a blending ratio of from 1:99 to 99:1 by volume. 
   
   
       18 . A process as claimed in  claim 15 , wherein the fuel produced by the process is a fuel as claimed in  claim 1 . 
   
   
       19 . (canceled) 
   
   
       20 . (canceled) 
   
   
       21 . (canceled) 
   
   
       22 . (canceled)