Compositions, and Methods and Uses Relating Thereto

Abstract

A fuel oil composition comprising a blended fuel oil having a sulfur content of less than 5000 ppm and an additive wherein the additive is a copolymer comprising maleic anhydride derived units and α-olefin derived units.

1 . A fuel oil composition comprising a blended fuel oil having a sulfur content of less than 5000 ppm and an additive wherein the additive is a copolymer comprising maleic anhydride derived units and α-olefin derived units. 
     
     
         2 . The fuel oil composition according to  claim 1  wherein the fuel oil comprises at least one distillate fuel component and at least one residual fuel component. 
     
     
         3 . The fuel oil composition according to  claim 2  wherein the fuel oil comprises from 5 to 95 wt % of residual fuel components and from 5 to 95 wt % of one or more fuel components selected from distillate fuel components and cracked fuel components. 
     
     
         4 . The fuel oil composition according to  claim 1  wherein the maleic anhydride derived units of the copolymer are present as underivatized anhydride moieties and/or as carboxylic acid moieties. 
     
     
         5 . The fuel oil composition according to  claim 1  wherein the α-olefin derived units contain 12 to 36 carbon atoms. 
     
     
         6 . The fuel oil composition according to  claim 1  wherein the maleic anhydride/α-olefin copolymer is present in an amount of from 50 to 5000 ppm. 
     
     
         7 . The fuel oil composition according to  claim 1  wherein the copolymer additive has a number average molecular weight of 5000 to 20000. 
     
     
         8 . The fuel oil composition according to  claim 1  which comprises one or more further additives selected from:
 (i) conductivity improvers; 
 (ii) combustion improvers; 
 (iii) asphaltene dispersants; 
 (iv) fuel antioxidants; 
 (v) cold flow improvers; 
 (vi) wax anti-setting agents; 
 (vii) biofuel instability inhibitors; 
 (viii) blended fuel separation inhibitors; 
 (ix) other detergents/dispersants. 
 
     
     
         9 . The fuel oil composition according to  claim 1  wherein the fuel oil comprising the additive has improved stability compared with an equivalent unadditised fuel oil. 
     
     
         10 . A method of preparing a fuel oil composition, the method comprising admixing an additive with a first component fuel and with a second component fuel wherein the resultant fuel oil composition has a sulfur content of less than 5000 ppm and wherein the additive is a copolymer comprising maleic anhydride derived units and α-olefin derived units. 
     
     
         11 . The method according to  claim 10  wherein the additive is mixed with the first component fuel before the first component fuel is mixed with the second component fuel. 
     
     
         12 . The method according to  claim 10  wherein one or more further component fuels are mixed to provide the fuel oil composition. 
     
     
         13 . A method of improving the stability of a blended fuel oil having a sulfur content of less than 5000 ppm, the method comprising mixing into the fuel oil an additive which is a copolymer comprising maleic anhydride derived units and α-olefin derived units. 
     
     
         14 . The method according to  claim 13  wherein the additive is mixed into a component fuel used to prepare the fuel oil composition. 
     
     
         15 . (canceled) 
     
     
         16 . The method according to  claim 13  wherein the improvement in stability is measured by improved storage stability and/or improved thermal stability and/or improved oxidation stability.