Cold Flow Improvement of Distillate Fuels Using Alpha-Olefin Compositions

Abstract

The cold flow of middle distillate fuels may be improved by adding an effective improving amount of one or more alpha-olefin compositions. The compositions include, but are not necessarily limited to, polymers of alpha-olefins per se, copolymerized or grafted alpha-olefins with maleic anhydride, acrylic acid, vinyl acetate, alkyl acrylates, methacrylic acid, and/or alkyl methacrylates. These resulting copolymers or grafted polymers may be blended with alkylphenol-formaldehyde resins, which in turn may be blended with ethylene-vinyl acetate (EVA) copolymer. In a non-limiting example, the cold filter plugging point (CFPP) may be synergistically improved as compared with the expected additive effect of using the components separately.

What is claimed is: 
     
         1 . A method for improving cold flow of a distillate fuel comprising adding to the distillate fuel an effective amount of an additive to improve a cold flow property, where the additive is selected from the group consisting of:
 polymerized alpha-olefins;   alpha-olefins copolymerized or reacted with a second component selected from the group consisting of maleic anhydride, acrylic acid, vinyl acetate, alkyl acrylates, methacrylic acid, alkyl methacrylates, and combinations thereof to give a reaction product;   alpha-olefins copolymerized or reacted with a second component selected from the group consisting of maleic anhydride, acrylic acid, vinyl acetate, alkyl acrylates, methacrylic acid, alkyl methacrylates, and combinations thereof to give a reaction product, where the reaction product is in turn blended with alkylphenol-formaldehyde resins; and   alpha-olefins copolymerized or reacted with a second component selected from the group consisting of maleic anhydride, acrylic acid, vinyl acetate, alkyl acrylates, methacrylic acid, alkyl methacrylates, and combinations thereof to give a reaction product, where the reaction product is in turn blended with alkylphenol-formaldehyde resins, which compositions are further blended with ethylene-vinyl acetate (EVA) copolymer.   
     
     
         2 . The method of  claim 1  where the alpha-olefin has from 6 to 30 carbon atoms. 
     
     
         3 . The method of  claim 1  when:
 where the alpha-olefin is copolymerized with or reacted with maleic anhydride, the mole ratio of maleic anhydride to alpha olefin ranges from about 0.03/1 to 3/1; 
 where the alpha-olefin is copolymerized with or reacted with acrylic acid, the mole ratio of acrylic acid to alpha-olefin ranges from about 0.04/1 to about 0.9/1; and 
 where the alpha-olefin is copolymerized with or reacted with vinyl acetate, the mole ratio of vinyl acetate to alpha-olefin ranges from about 0.04/1 to about 2/1. 
 
     
     
         4 . The method of  claim 1  where:
 the weight average molecular weight of the reaction product ranges from about 1000 to about 20,000; 
 the weight average molecular weight of the alkylphenol-formaldehyde resins ranges from about 2000 to about 20,000; and 
 the weight average molecular weight of the EVA copolymer ranges from about 1000 to about 10,000. 
 
     
     
         5 . The method of  claim 1  where the effective amount of the additive ranges from about 10 ppm-vol to about 10,000 ppm-vol. 
     
     
         6 . The method of  claim 1  where the improved cold flow property is improved cold filter plugging point (CFPP), and where the CFPP is improved as compared to an otherwise identical distillate fuel absent the alpha-olefin component. 
     
     
         7 . The method of  claim 1  where the additive is not esterified. 
     
     
         8 . A method for improving cold flow of a distillate fuel comprising adding to the distillate fuel from about 10 ppm-vol to about 10,000 ppm-vol of an additive to improve a cold flow property, where the additive is selected from the group consisting of:
 polymerized alpha-olefins;   alpha-olefins copolymerized or reacted with a second component selected from the group consisting of maleic anhydride, acrylic acid, vinyl acetate, alkyl acrylates, methacrylic acid, alkyl methacrylates, and combinations thereof to give a reaction product;   alpha-olefins copolymerized or reacted with a second component selected from the group consisting of maleic anhydride, acrylic acid, vinyl acetate, alkyl acrylates, methacrylic acid, alkyl methacrylates, and combinations thereof to give a reaction product, where the reaction product is in turn blended with alkylphenol-formaldehyde resins; and   alpha-olefins copolymerized or reacted with a second component selected from the group consisting of maleic anhydride, acrylic acid, vinyl acetate, alkyl acrylates, methacrylic acid, alkyl methacrylates, and combinations thereof to give a reaction product, where the reaction product is in turn blended with alkylphenol-formaldehyde resins, which compositions are further blended with ethylene-vinyl acetate (EVA) copolymer;   
       where the alpha-olefin has from 6 to 30 carbon atoms. 
     
     
         9 . The method of  claim 8  when:
 where the alpha-olefin is copolymerized with or reacted with maleic anhydride, the mole ratio of maleic anhydride to alpha olefin ranges from about 0.03/1 to 3/1; 
 where the alpha-olefin is copolymerized with or reacted with acrylic acid, the mole ratio of acrylic acid to alpha-olefin ranges from about 0.04/1 to about 0.9/1; and 
 where the alpha-olefin is copolymerized with or reacted with vinyl acetate, the mole ratio of vinyl acetate to alpha-olefin ranges from about 0.04/1 to about 2/1. 
 
     
     
         10 . The method of  claim 8  where:
 the weight average molecular weight of the reaction product ranges from about 1000 to about 20,000; 
 the weight average molecular weight of the alkylphenol-formaldehyde resins ranges from about 2000 to about 20,000; and 
 the weight average molecular weight of the EVA copolymer ranges from about 1000 to about 10,000. 
 
     
     
         11 . The method of  claim 8  where the improved cold flow property is improved cold filter plugging point (CFPP), and where the CFPP is improved as compared to an otherwise identical distillate fuel absent the alpha-olefin component. 
     
     
         12 . The method of  claim 9  where the additive is not esterified. 
     
     
         13 . A distillate fuel composition having improved cold flow comprising:
 a distillate fuel; and   an effective amount to improve a cold flow property the distillate fuel of an additive, where the additive is selected from the group consisting of:
 polymerized alpha-olefins; 
 alpha-olefins copolymerized or reacted with a second component selected from the group consisting of maleic anhydride, acrylic acid, vinyl acetate, alkyl acrylates, methacrylic acid, alkyl methacrylates, and combinations thereof to give a reaction product; 
 alpha-olefins copolymerized or reacted with a second component selected from the group consisting of maleic anhydride, acrylic acid, vinyl acetate, alkyl acrylates, methacrylic acid, alkyl methacrylates, and combinations thereof to give a reaction product, where the reaction product is in turn blended with alkylphenol-formaldehyde resins; and 
 alpha-olefins copolymerized or reacted with a second component selected from the group consisting of maleic anhydride, acrylic acid, vinyl acetate, alkyl acrylates, methacrylic acid, alkyl methacrylates, and combinations thereof to give a reaction product, where the reaction product is in turn blended with alkylphenol-formaldehyde resins, which compositions are blended with ethylene-vinyl acetate (EVA) copolymer. 
   
     
     
         14 . The distillate fuel of  claim 13  where the alpha-olefin has from 6 to 30 carbon atoms. 
     
     
         15 . The distillate fuel of  claim 13  when:
 where the alpha-olefin is copolymerized with or reacted with maleic anhydride, the mole ratio of maleic anhydride to alpha olefin ranges from about 0.03/1 to 3/1; 
 where the alpha-olefin is copolymerized with or reacted with acrylic acid, the mole ratio of acrylic acid to alpha-olefin ranges from about 0.04/1 to about 0.9/1; and 
 where the alpha-olefin is copolymerized with or reacted with vinyl acetate, the mole ratio of vinyl acetate to alpha-olefin ranges from about 0.04/1 to about 2/1. 
 
     
     
         16 . The distillate fuel of  claim 13  where:
 the weight average molecular weight of the reaction product ranges from about 1000 to about 20,000; 
 the weight average molecular weight of the alkylphenol-formaldehyde resins ranges from about 2000 to about 20,000; and 
 the weight average molecular weight of the EVA copolymer ranges from about 1000 to about 10,000. 
 
     
     
         17 . The distillate fuel of  claim 13  where the effective amount of the additive ranges from about 10 ppm-vol to about 10,000 ppm-vol. 
     
     
         18 . The distillate fuel of  claim 13  where the improved cold flow property is improved cold filter plugging point (CFPP), and where the CFPP is improved as compared to an otherwise identical distillate fuel absent the alpha-olefin component. 
     
     
         19 . The distillate fuel of  claim 13  where the additive is not esterified.