Cerium oxide nanoparticles as fuel additives

Abstract

A method of improving the efficiency of a fuel is described which comprises adding to the fuel prior to the introduction of the fuel to a vehicle or other apparatus comprising an internal combustion engine cerium oxide and/or doped cerium oxide and, optionally, one or more fuel additives.

1 . A method of improving the efficiency of a fuel for an internal combustion engine which comprises adding to the fuel prior to the introduction of the fuel to a vehicle or other apparatus comprising an internal combustion engine cerium oxide and/or doped cerium oxide and, optionally, one or more fuel additives.  
   
   
       2 . A method according to  claim 1  which comprises adding cerium oxide which has been doped with a divalent or trivalent metal or metalloid which is a rare earth metal, a transition metal or a metal of group IIA, IIIB, VB or VIB of the Periodic Table.  
   
   
       3 . A method according to  claim 2  wherein the metal is a transition metal.  
   
   
       4 . A method according to  claim 3  wherein the metal is rhodium, copper, silver, gold, palladium, platinum, iron, manganese, chromium, cobalt, vanadium, zirconium or titanium.  
   
   
       5 . A method according to  claim 2  wherein the metal is terbium, praeseodymium, samarium, gadolinium, antimony, selenium, gallium, magnesium, beryllium, boron or calcium.  
   
   
       6 . A method according to  claim 1  wherein the cerium oxide and/or doped cerium oxide has a size not exciding 1 micron.  
   
   
       7 . A method according to  claim 6  wherein the cerium oxide and/or doped cerium oxide has a size from 1 to 300 nm.  
   
   
       8 . A method according to  claim 1  wherein the cerium oxide and/or doped cerium oxide has been coated with an organic acid, anhydride or ester or a Lewis base.  
   
   
       9 . A method according to  claim 8  wherein the coating is of a dicarboxylic acid anhydride.  
   
   
       10 . A method according to  claim 9  wherein the coating is of an alkenyl succinic anhydride.  
   
   
       11 . A method according to  claim 10  wherein the succinic anhydride is dodecenyl succinic anhydride, octadecenyl succinic anhydride or polyisobutenyl succinic anhydride.  
   
   
       12 . A method according to  claim 1  wherein the fuel is diesel fuel.  
   
   
       13 . A method according to  claim 1  wherein the cerium oxide and/or doped cerium oxide is added with a solvent which is an aliphatic or aromatic hydrocarbon or an aliphatic alcohol.  
   
   
       14 . A method according to  claim 1  wherein the cerium oxide and/or doped cerium oxide is added to the fuel at the refinery.  
   
   
       15 . A method according to  claim 1  wherein the cerium oxide and/or doped cerium oxide is added at a fuel depot.  
   
   
       16 . A method according to  claim 1  wherein the cerium oxide and/or doped cerium oxide is added at the filling station forecourt.  
   
   
       17 . A method according to  claim 1  wherein the cerium oxide and/or doped cerium oxide is added together with one or more of a detergent, dehazer, anti-foaming agent, ignition improver, anti-rust agent, reodorant, anti-oxidant, metal deactivator, lubricity agent or demulsifier.  
   
   
       18 . A method according to  claim 17  wherein the cerium oxide and/or doped cerium oxide is added together with a detergent.  
   
   
       19 . A method according to  claim 18  wherein the detergent is a basic nitrogen-containing ashless detergent.  
   
   
       20 . A method according to  claim 19  wherein the detergent is a succinimide which has an average of at least 3 nitrogen atoms per molecule.  
   
   
       21 . A method according to  claim 20  wherein the succinimide is derived from an alkyl or alkenyl succinic acylating agent having at least 35 carbon atoms in the alkyl or alkenyl part and an alkylene polyamine mixture having an average of at least 3 nitrogen atoms per molecule.  
   
   
       22 . A method according to  claim 20  wherein the succinimide is derived from a polyisobutenyl succinic acylating agent obtainable from a polyisobutene having a number average molecular weight of 500 to 10,000 and an ethylene polyamine having an average composition from triethylene tetramine to pentaethylene hexamine.  
   
   
       23 . A method according to  claim 21  wherein the aliphatic chain of the succinimide has a molecular weight from 500 to 2500.  
   
   
       24 . A method according to  claim 23  wherein the aliphatic chain of the succinimide has a molecular weight from 750 to 1500.  
   
   
       25 . A method according to  claim 18  wherein the cerium oxide and/or doped cerium oxide is added together with at least one of an anti-foaming agent, demulsifier or anti-rust agent.  
   
   
       26 . A method according to  claim 1  wherein the cerium oxide and/or doped cerium oxide is added at a concentration not exceeding 20 ppm.  
   
   
       27 . A method according to  claim 26  wherein the cerium oxide and/or doped cerium oxide is added in an amount not exceeding 10 ppm.  
   
   
       28 . (canceled)  
   
   
       29 . A fuel additive which comprises cerium oxide and/or doped cerium oxide and a detergent.  
   
   
       30 . A fuel additive according to  claim 29  wherein the concentration of cerium oxide and/or doped cerium oxide is from 0.1 to 10% by weight.  
   
   
       31 . A fuel additive according to  claim 30  wherein the concentration of cerium oxide and/or doped cerium oxide is from 0.5 to 5% by weight.  
   
   
       32 . A fuel additive which comprises cerium oxide and/or doped cerium oxide and a detergent wherein the cerium oxide is one defined in  claim 2 .  
   
   
       33 . A fuel additive according to  claim 32  wherein the detergent is a basic nitrogen-containing ashless detergent.  
   
   
       34 . A fuel additive according to  claim 33  wherein the detergent is a succinimide which has an average of at least 3 nitrogen atoms per molecule.  
   
   
       35 . A fuel additive according to  claim 34  wherein the succinimide is derived from an alkyl or alkenyl succinic acylating agent having at least 35 carbon atoms in the alkyl or alkenyl part and an alkylene polyamine mixture having an average of at least 3 nitrogen atoms per molecule.  
   
   
       36 . A fuel additive according to  claim 34  wherein the succinimide is derived from a polyisobutenyl succinic acylating agent obtainable from a polyisobutene having a number average molecular weight of 500 to 10,000 and an ethylene polyamine having an average composition from triethylene tetramine to pentaethylene hexamine.  
   
   
       37 . A fuel additive according to  claim 35  wherein the aliphatic chain of the succinimide has a molecular weight 500 to 2500.  
   
   
       38 . A fuel additive according to  claim 37  wherein the aliphatic chain of the succinimide has a molecular weight 750 to 1500.  
   
   
       39 . A fuel additive according to  claim 32  which also comprises one or more of a dehazer, anti-foaming agent, ignition improver, anti-rust agent, reodorant, anti-oxidant, metal deactivator, lubricity agent or demulsifier.  
   
   
       40 . A fuel additive according to  claim 39  which comprise one or more of an anti-foam agent, an anti-rust agent or a demulsifier.  
   
   
       41 . A fuel additive according to  claim 29  which comprises a solvent which is an aliphatic or aromatic hydrocarbon or an aliphatic alcohol.  
   
   
       42 . (canceled)