Conductivity improving additive for fuel oil compositions

Abstract

An fuel oil containing a conductivity improving additive comprising the combination of: (a) an oil soluble succinimide dispersant comprising a functionalized hydrocarbon reacted with an alkylene polyamine and (b) a conductivity improver comprising (i) an olefin polysulfone and (ii) a polymeric polyamine reaction product of epichlorohydrin and an aliphatic primary monoamine or an N-aliphatic hydrocarbyl alkylene diamine, or the sulfonic acid salt of the polymeric polyamine reaction product or (c) the combination of an oil soluble succinimide dispersant comprising a functionalized hydrocarbon reacted with a heavy polyamine and (d) a conductivity improver comprising a hydrocarbon soluble copolymer of an alkylvinyl monomer and a cationic vinyl monomer, wherein the copolymer has an alkylvinyl monomer unit to cationic vinyl monomer unit ratio of from about 1:1 to about 10:1, the copolymer having an average molecular weight of from about 800 to about 1,000,000.

1 . An improved fuel oil composition, the composition comprising a fuel oil having an inherent conductivity of less than 15 pS/m and a two component additive system; wherein the two component additive system comprises the combination of: 
 (a) an oil soluble succinimide dispersant comprising a functionalized hydrocarbon reacted with an alkylene polyamine; and    (b) a conductivity improver comprising (i) an olefin polysulfone and (ii) a polymeric polyamine reaction product of epichlorohydrin and an aliphatic primary monoamine or an N-aliphatic hydrocarbyl alkylene diamine, or the sulfonic acid salt of the polymeric polyamine reaction product,    or the combination of:    (c) an oil soluble succinimide dispersant comprising a functionalized hydrocarbon reacted with a heavy polyamine, and    (d) a conductivity improver comprising a hydrocarbon soluble copolymer of an alkylvinyl monomer and a cationic vinyl monomer, wherein the copolymer has an alkylvinyl monomer unit to cationic vinyl monomer unit ratio of from about 1:1 to about 10:1, the copolymer having an average molecular weight of from about 800 to about 1,000,000.    
     
     
         2 . A composition according to  claim 1 , wherein the dispersant is a polyisobutenyl succinimide.  
     
     
         3 . A composition according to  claim 1  which comprises an antioxidant.  
     
     
         4 . A composition according to  claim 1  which comprises a metal deactivator.  
     
     
         5 . A composition according to  claim 1 , in which the polyisobutenyl has a molecular weight of 900-3000.  
     
     
         6 . A composition according to  claim 1  which also comprises one or more additives selected from the group consisting of cold flow improvers, lubricity additives, corrosion inhibitors, anti-icing additives, biocides, thermal stability additives, anti-foam agents, anti-rust agents, demulsifiers, detergents, dispersants, stabilisers, static dissipator additives and cetane improvers.  
     
     
         7 . A composition according to  claim 1 , in which the fuel oil is a turbine combustion fuel oil.  
     
     
         8 . A composition according to  claim 1 , in which the fuel oil is a diesel fuel or a heating oil.  
     
     
         9 . A conductivity improving additive comprising the combination of: 
 (a) an oil soluble succinimide dispersant comprising a functionalized hydrocarbon reacted with an alkylene polyamine; and    (b) a conductivity improver comprising (i) an olefin polysulfone and (ii) a polymeric polyamine reaction product of epichlorohydrin and an aliphatic primary monoamine or an N-aliphatic hydrocarbyl alkylene diamine, or the sulfonic acid salt of the polymeric polyamine reaction product,    or the combination of:    (c) an oil soluble succinimide dispersant comprising a functionalized hydrocarbon reacted with a heavy polyamine, and    (d) a conductivity improver comprising a hydrocarbon soluble copolymer of an alkylvinyl monomer and a cationic vinyl monomer, wherein the copolymer has an alkylvinyl monomer unit to cationic vinyl monomer unit ratio of from about 1:1 to about 10:1, the copolymer having an average molecular weight of from about 800 to about 1,000,000.    
     
     
         10 . The use of an additive according to  claim 9  to improve the conductivity of a fuel oil.