Low-Temperature Fluidity Improver for Biodiesel Fuel

Abstract

Provided is a low-temperature fluidity improver capable of efficiently improving the low-temperature fluidity of a biodiesel fuel. The low-temperature fluidity improver for biodiesel fuels includes a specific aromatic carboxylic acid-based compound.

1 - 8 . (canceled) 
     
     
         9 . A biodiesel fuel composition, comprising:
 a low-temperature fluidity improver for a biodiesel fuel comprising:   (i) a compound represented by the following formula (1) as a component (A):   
       
         
           
           
               
               
           
         
         wherein R 1  and R 3  each represent a hydrogen atom or a hydrocarbon group which may contain one or more atoms selected from sulfur atoms, oxygen atoms and nitrogen atoms, R 2  and R 4  each represent a hydrogen atom, a carboxyl group, or a hydrocarbon group which may contain one or more atoms selected from sulfur atoms, oxygen atoms and nitrogen atoms, and R 2  and R 3  or R 3  and R 4  may be bonded to each other to form a ring, provided that R 2  and R 4  do not simultaneously represent carboxyl groups, 
         wherein the compound represented by the formula (1) comprises isophthalic acid or trimellitic acid, and 
         a compound represented by the following formula (2) as a component (B): 
       
       
         
           
           
               
               
           
         
       
       wherein R 5  and R 6  each represent a hydrogen atom or a hydrocarbon group which has 8 to 22 carbon atoms and which may contain oxygen atoms and/or nitrogen atoms, provided that R 5  and R 6  do not simultaneously represent hydrogen atoms; and
 a biodiesel fuel. 
 
     
     
         10 . The biodiesel fuel composition according to  claim 9 , further comprising a cetane number improver and/or a detergent. 
     
     
         11 . The biodiesel fuel composition according to  claim 9 , further comprising one or more additives selected from the group consisting of a solvent, an antioxidant, a metal deactivator, a deicing agent, a corrosion inhibitor, an antistatic agent, a colorant, and a defoaming agent. 
     
     
         12 . The biodiesel fuel composition according to  claim 9 , wherein R 5  and R 6  in the compound represented by the formula (2) each represent a hydrogen atom or a linear alkyl group having 8 to 16 carbon atoms.