Biodiesel-fischer-tropsch hydrocarbon blend

Abstract

The invention provides a biodiesel and Fischer-Tropsch derived hydrocarbon blend, whereby the characteristics of the Fischer-Tropsch derived hydrocarbon are used to improve the diesel-like characteristics of biodiesel. The invention also provides a blending component for Compression Ignition engine fuel as well as a method of adjusting the density of a hydrocarbon fuel.

1 . A hydrocarbon composition for use in compression ignition engines (CI), said composition comprising a blend of Fischer-Tropsch derived hydrocarbon which includes hydroprocessed Fischer-Tropsch hydrocarbon, send blend having a density of below 0.8 kg/l at 15° C. and bio-diesel having a density of above 0.8 kg/l at 15° C. in a volumetric ratio of from 1:4 to 4:1, said composition having a density of above 0.8 kg/l at 15° C. while maintaining the Fischer-Tropsch derived hydrocarbon's net volumetric heating valve.  
     
     
         2 . A hydrocarbon composition as claimed in  claim 1 , having a viscosity of below 4.1 cSt.  
     
     
         3 . A hydrocarbon composition as claimed in  claim 1 , wherein the volumetric ratio is from 1:2 to 2:1.  
     
     
         4 . A hydrocarbon composition as claimed in  claim 3 , wherein the volumetric blending ratio is 1:1.  
     
     
         5 . A hydrocarbon composition as claimed in  claim 1 , having a cetane number in excess of 50.  
     
     
         6 . A hydrocarbon composition as claimed in  claim 5 , having a cetane number in excess of 55.  
     
     
         7 . A hydrocarbon composition as claimed in  claim 1 , having a CFPP in accordance with IP 309 of below −12° C.  
     
     
         8 . A hydrocarbon composition as claimed in  claim 7 , having a CFPP in accordance with IP 309 of below −15° C.  
     
     
         9 . A hydrocarbon composition as claimed in  claim 8 , wherein the biodiesel comprises of a mixture of linear C 10 -C 20  methyl esters with minor quantities of water, glycerol, and methanol.  
     
     
         10 . A hydrocarbon composition as claimed in  claim 1 , wherein the Fischer-Tropsch hydrocarbon which is blended with bio-diesel is derived from a Fischer-Tropsch synthesis process using a catalyst which is based on a metal selected from a group consisting of iron, cobalt, and ruthenium, or mixtures of two or more thereof.  
     
     
         11 . A hydrocarbon composition as claimed in  claim 1 , wherein the composition of the Fischer-Tropsch hydrocarbon includes a mixture of paraffins, olefins, and oxygenates.  
     
     
         12 . A hydrocarbon composition as claimed in  claim 11 , wherein the Fischer-Tropsch hydrocarbon comprises a mixture of both linear and branched C 9 -C 20  paraffins, C 9 -C 20  olefins, and C 7 -C 20  alcohols.  
     
     
         13 . A hydrocarbon composition as claimed in  claim 1 , wherein the Fischer-Tropsch hydrocarbon is a Fischer-Tropsch diesel.  
     
     
         14 . (Canceled)  
     
     
         15 . A blending component as claimed in  claim 14 , having a density of at least 0.8 kg/l at 15° C.  
     
     
         16 . A blending component as claimed in  claim 14 , having a viscosity below 4.1 cSt.  
     
     
         17 . A blending component as claimed in  claim 14 , wherein the volumetric blending ratio of Fischer-Tropsch derived hydrocarbon and biodiesel in the blending component is from 1:4 to 4:1.  
     
     
         18 . A blending component as claimed in  claim 14 , wherein the volumetric blending ratio of Fischer-Tropsch derived hydrocarbon and biodiesel in the blending component is from 1:2 to 2:1.  
     
     
         19 . A blending component as claimed in  claim 14 , wherein the volumetric blending ratio of Fischer-Tropsch derived hydrocarbon and biodiesel in the blending component is 1:1.  
     
     
         20 . A method of increasing the density of a hydrocarbon fuel composition having a densisty of below 0.8 kg/l to above 0.8 kg/l, said method including blending of bio-diesel into the fuel composition in a volumetric ratio of bio-diesel to hydrocarbon fuel composition of at least 1:3 as calculated before the blending in of the bio-diesel, thereby to obtain a resulting fuel composition having a density of above the 0.8 kg/l threshold and a net volumetric heating value of about 33 000 MJ/m 3  wherein said fuel composition includes hydroprocessed Fischer-Tropsch hydrocarbon.  
     
     
         21 . A method as claimed in  claim 20 , wherein the volumetric ratio is at least 1:2.  
     
     
         22 . A method as claimed in  claim 21 , wherein the volumetric ratio is about 1:1.  
     
     
         23 . (Canceled)