Conductivity improving combination of cerium oxide and detergents for diesel fuels

Abstract

The disclosure provides conductivity improving concentrates and methods for improving conductivity and reducing risks associated with static discharge in middle distillate fuel composition compositions, particularly diesel fuels. The conductivity improvement is provided with the combination of cerium oxide nanoparticles and dispersant/detergent and shows aged conductivity comparable to or higher than that obtained with conventional antistatic agents.

1 . An additive concentrate for a middle distillate fuel composition, said additive concentrate comprising an antistatic agent, said antistatic agent comprising, in combination, a dispersant and cerium oxide particles. 
     
     
         2 . The additive concentrate of  claim 1 , wherein said fuel comprises a diesel fuel. 
     
     
         3 . The additive concentrate of  claim 1 , wherein said antistatic agent contributes no more than 0.135 ppm of sulfur to the additive concentrate. 
     
     
         4 . The additive concentrate of  claim 1 , wherein the cerium oxide particles comprise nanoparticles. 
     
     
         5 . The additive concentrate of  claim 1 , wherein said dispersant comprises a succinimide dispersant. 
     
     
         6 . The additive concentrate of  claim 7 , wherein said succinimide dispersant is formed from tetraethylene pentamine. 
     
     
         7 . Use of the additive concentrate of  claim 1  to provide a conductivity measure of at least 500 pS/m in a middle distillate fuel after aging for 7 days at 21° C. 
     
     
         8 . A middle distillate fuel composition having improved conductivity, said fuel comprising an antistatic agent, said antistatic agent comprising, in combination, a dispersant and cerium oxide particles. 
     
     
         9 . The fuel of  claim 8 , wherein said fuel comprises a diesel fuel. 
     
     
         10 . The fuel of  claim 8 , wherein said antistatic agent contributes no more than 0.135 ppm of sulfur to the fuel composition. 
     
     
         11 . The fuel of  claim 8 , wherein said fuel has a conductivity of at least 500 pS/m after 7 days of aging at 21° C. 
     
     
         12 . The fuel of  claim 8 , wherein the cerium oxide particles comprise nanoparticles. 
     
     
         13 . The fuel of  claim 8 , wherein said dispersant comprises a succinimide dispersant. 
     
     
         14 . The fuel of  claim 13 , wherein said succinimide dispersant is formed from tetraethylene pentamine. 
     
     
         15 . Use of the fuel of  claim 8  in a combustion apparatus. 
     
     
         16 . A method of dispensing a middle distillate fuel composition comprising the steps of adding to a middle distillate fuel composition an antistatic agent comprising, in combination, a dispersant and cerium oxide particles in an amount sufficient to provide a conductivity benefit to said fuel. 
     
     
         17 . The method of  claim 16 , further comprising the step of dispensing said fuel composition prior to the conductivity of said fuel composition dropping below 50 pS/m. 
     
     
         18 . The method of  claim 17 , wherein said dispensing step comprises dispensing said fuel composition into a bulk container. 
     
     
         19 . The method of  claim 16 , wherein said dispersant and said cerium oxide particles are pre-blended in an additive concentrate prior to addition to said fuel. 
     
     
         20 . The method of  claim 16 , wherein said fuel comprises a diesel fuel. 
     
     
         21 . The method of  claim 16 , wherein said antistatic agent contributes no more than 0.135 ppm of sulfur to the fuel composition. 
     
     
         22 . The method of  claim 16 , wherein said cerium oxide particles comprise nanoparticles. 
     
     
         23 . The method of  claim 16 , wherein said detergent comprises a succinimide detergent. 
     
     
         24 . The method of  claim 23 , wherein said succinimide dispersant is formed from tetraethylene pentamine. 
     
     
         25 . A method of reducing a risk of ignition or explosion from static discharge, comprising the steps of providing a middle distillate fuel composition; adding a combination of a dispersant and cerium oxide particles to said fuel composition to improve conductivity in said fuel composition; thereby reducing the risk of static discharge in said fuel composition. 
     
     
         26 . The method of  claim 25 , further comprising the step of dispensing the fuel composition. 
     
     
         27 . The method of  claim 26 , wherein said dispensing step comprises dispensing said fuel composition into a bulk container. 
     
     
         28 . The method of  claim 26 , wherein the conductivity in said fuel composition is at least 50 pS/m at the time and temperature of delivery. 
     
     
         29 . The method of  claim 25 , wherein dispersant and said cerium oxide particles are pre-blended in an additive concentrate prior to being added to said fuel composition. 
     
     
         30 . The method of  claim 25 , wherein said fuel composition comprises a diesel fuel. 
     
     
         31 . The method of  claim 25 , wherein said middle distillate fuel is substantially free of a sulfur-containing conductivity improver. 
     
     
         32 . The method of  claim 25 , wherein the combination of dispersant and cerium oxide particles add no more than 0.135 ppm of sulfur to the fuel composition. 
     
     
         33 . The method of  claim 25 , wherein the cerium oxide particles comprise nanoparticles. 
     
     
         34 . The method of  claim 25 , wherein said dispersant comprises a succinimide dispersant. 
     
     
         35 . The method of  claim 34 , wherein said succinimide dispersant is formed from tetraethylene pentamine.