Stabilized biodiesel fuel compositions

Abstract

Disclosed are stabilized biodiesel fuel compositions, which compositions comprise a biodiesel fuel, for example the methyl esters of the fatty acids of rapeseed or soy oil, which compositions comprise a biodiesel fuel and an effective stabilizing amount of a combination of i) one or more compounds selected from the group consisting of the sterically hindered phenolic antioxidants and ii) one or more compounds selected from the group consisting of the triazole metal deactivators.

1 . A biodiesel fuel composition stabilized against the deleterious effects of heat, light, oxygen and metals, which composition comprises
 a biodiesel fuel and   an effective stabilizing amount of a combination of   i) one or more compounds selected from the group consisting of the sterically hindered phenolic antioxidants and   ii) one or more compounds selected from the group consisting of the triazole metal deactivators.   
     
     
         2 . A composition according to  claim 1  comprising one or more phenolic antioxidants selected from the group consisting of butylated phenol, butylated hydroxytoluene, butylated hydroxyanisole, tocopherol, benzylphosphonates, esters of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid with mono- or polyhydric alcohols, esters of β-(5-tert-butyl-4-hydroxy-3-methylphenyl)propionic acid with mono- or polyhydric alcohols, esters of β-(3,5-dicyclohexyl-4-hydroxyphenyl)propionic acid with mono- or polyhydric alcohols and esters of 3,5-di-tert-butyl-4-hydroxyphenyl acetic acid with mono- or polyhydric alcohols. 
     
     
         3 . A composition according to  claim 1  comprising one or more hindered phenolic antioxidants selected from the group consisting of 2,6-di-tert-butylphenol, 2,6-di-tert-butyl-4-methylphenol (BHT), 2,2′-methylene bis-(4,6-di-tert-butylphenol), 1,6-hexamethylene-bis-(3,5-di-tert-butyl-4-hydroxyhydrocinnamate), ((3,5-bis(1,1-dimethylethyl)-4-hydroxphenyl)methylthio)acetic acid C 10 -C 14  isoalkyl esters, 3,5-di-tert-butyl-4-hydroxyhydrocinnamic acid C 6 -C 9 alkyl esters, 3,5-di-tert-butyl-4-hydroxyhydrocinnamic acid methyl ester, tetrakis-(3-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionyloxymethyl)methane, thiodiethylene bis(3,5-di-tert-butyl-4-hydroxyhydrocinnamate), octadecyl 3,5-di-tert-butyl-4-hydroxyhydrocinnamate and 2,5-di-tert-butylhydroquinone. 
     
     
         4 . A composition according to  claim 1  comprising one or more hindered phenolic antioxidants selected from the group consisting of 2,6-di-tert-butylphenol, 3,5-di-tert-butyl-4-hydroxyhydrocinnamic acid methyl ester and tetrakis-(3-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionyloxymethyl)methane. 
     
     
         5 . A composition according to  claim 1  comprising one or more triazole metal deactivators selected from compounds of the formula 
       
         
           
           
               
               
           
         
         where 
         R 1  and R 2  are the same or different and are hydrogen, C 1 -C 20 alkyl, C 3 -C 20 alkenyl, C 5 -C 12 cycloalkyl, C 7 -C 13 aralkyl, C 6 -C 10 aryl or hydroxy or R 1  and R 2 , together with the nitrogen atom to which they are each attached may form a 5-, 6- or 7-membered heterocylic ring, or R 1  and R 2  are a group of formula
   R 3 X[(—R 4 —)O] n (—R 4 )— 
 
         where 
         X is O, S or NR 3 , 
         R 3  is hydrogen or C 1 -C 20 alkyl, 
         R 4  is C 1 -C 12 alkylene, 
         n is 0 or an integer from 1 to 6, 
         or one of R 1  and R 2  is a group of formula 
       
       
         
           
           
               
               
           
         
         or R 2  is a group of formula (II) and R 1  is a group of formula
   [R 4 ] n —N(R 5 )-A-[N(R 5 ) 2 ] m    
 
         where 
         m is 0 or 1 and, when m is zero, A is a group of formula (II) and, when m is 1, A is alkylene or C 6 -C 10  arylene and R 5  is a group of formula (II). 
       
     
     
         6 . A composition according to  claim 5  comprising one or more triazole metal deactivators selected from the group consisting of 
       1-(or 4)-(dimethylaminomethyl)triazole, 
       1-(or 4)-(diethylaminomethyl)triazole, 
       1-(or 4)-(di-isopropylaminomethyl)triazole, 
       1-(or 4)-(di-n-butylaminomethyl)triazole, 
       1-(or 4)-(di-n-hexylaminomethyl)triazole, 
       1-(or 4)-(di-isooctylaminomethyl)triazole, 
       1-(or 4)-(di-(2-ethylhexyl)aminomethyl)triazole, 
       1-(or 4)-(di-n-octylaminomethyl)triazole, 
       1-(or 4)-(di-n-decylaminomethyl)triazole, 
       1-(or 4)-(di-n-dodecylaminomethyl)triazole, 
       1-(or 4)-(di-n-octadecylaminomethyl)triazole, 
       1-(or 4)-(di-n-eicosylaminomethyl)triazole, 
       1-(or 4)-[di-(prop-2′-enyl)aminomethyl]triazole, 
       1-(or 4)-[di-(but-2′-enyl)aminomethyl]triazole, 
       1-(or 4)-[di-(eicos-2′-enyl)aminomethyl]triazole, 
       1-(or 4)-(di-cyclohexylaminomethyl)triazole, 
       1-(or 4)-(di-benzylaminomethyl)triazole, 
       1-(or 4)-(di-phenylaminomethyl)triazole, 
       1-(or 4)-(4′-morpholinomethyl)triazole, 
       1-(or 4)-(1′-pyrrolidinomethyl)triazole, 
       1-(or 4)-(1′-piperidinomethyl)triazole, 
       1-(or 4)-(1′-perhydroroazepinomethyl)triazole, 
       1-(or 4)-(2′,2″-dihydroxyethyl)aminomethyl]triazole, 
       1-(or 4)-(dibutoxypropyl-aminomethyl)triazole, 
       1-(or 4)-(dibutylthiopropyl-aminomethyl)triazole, 
       1-(or 4)-(di-butylaminopropyl-aminomethyl)triazole, 
       N,N-bis-(1- or 4-triazolylmethyl)laurylamine, 
       N,N-bis-(1- or 4-triazolylmethyl)oleylamine, 
       N,N-bis-(1- or 4-triazolylmethyl)ethanolamine and 
       N,N,N′,N′-tetra(1- or 4-triazolylmethyl)ethylene diamine. 
     
     
         7 . A composition according to  claim 5  comprising 1-(di-isooctylaminomethyl)-1,2,4-triazole or 1-(di-(2-ethylhexyl)aminomethyl) 1,2,4-triazole. 
     
     
         8 . A composition according to  claim 1  comprising one or more triazole metal deactivators selected from compounds of the formula 
       
         
           
           
               
               
           
         
         where 
         R 6  is C 1 -C 12 alkyl, 
         R 7  is C 1 -C 12 alkyl, C 1 -C 12 alkyl interrupted by one or more O atoms or is C 5 -C 12 cycloalkyl and 
         R 8  and R 9  are hydrogen or methyl. 
       
     
     
         9 . A composition according to  claim 8  comprising one or more triazole metal deactivators selected from the group consisting of 
       1-(2-methoxyprop-2-yl)tolyltriazole, 
       1-(1-methoxyethyl)tolyltriazole, 
       1-(1-methoxpropyl)tolyltriazole, 
       1-(1-isobutoxybutyl)tolyltriazole, 
       1-(1-tert-butoxybutyl)tolyltriazole, 
       1-(1-hexyloxybutyl)tolyltriazole, 
       1-(1-octyloxybutyl)tolyltriazole, 
       1-(1-butoxy-2-methylpropyl)tolyltriazole, 
       1-(1-dodecyloxybutyl)tolyltriazole, 
       1-(1-isopropyloxyethyl)tolyltriazole, 
       1-(1-isopropyloxypropyl)tolyltriazole, 
       1-(1-isopropyloxybutyl)tolyltriazole, 
       1-(1-cyclohexyloxypropyl)tolyltriazole, 
       1-(1-cyclohexyloxyheptyl)tolyltriazole, 
       1-(1-cyclohexyloxybutyl)tolyltriazole, 
       1-[1-(2-methoxyethoxy)butyl]tolyltriazole and 
       1-[1-(2-ethoxyethoxy)butyl]tolyltriazole. 
     
     
         10 . A composition according to  claim 8  comprising 1-(2-methoxyprop-2-yl)tolyltriazole, 1-(1-cyclohexyloxypropyl)tolyltriazole, 1-(1-cyclohexyloxyheptyl)tolyltriazole or 1-(1-cyclohexyloxybutyl)tolyltriazole. 
     
     
         11 . A composition according to  claim 1  comprising one or more triazole metal deactivators selected from compounds of the formula 
       
         
           
           
               
               
           
         
         where 
         R 10  is hydrogen or C 1 -C 12 alkyl, 
         R 11  at and R 12  are the same or different and are hydrogen, C 1 -C 20 alkyl, C 3 -C 20 alkenyl, C 5 -C 12 cycloalkyl, C 7 -C 13 aralkyl, C 6 -C 10 aryl or hydroxy or R 11  and R 12 , together with the nitrogen atom to which they are each attached may form a 5-, 6- or 7-membered heterocylic ring, or R 11  and R 12  are a group of formula
   R 13 X[(—R 14 —)O] n (—R 14 )— 
 
         where 
         X is O, S or NR 13 , 
         R 13  is hydrogen or C 1 -C 20 alkyl, 
         R 14  is C 1 -C 12 alkylene, 
         n is 0 or an integer from 1 to 6, 
         or one of R 11  and R 12  is a group of formula 
       
       
         
           
           
               
               
           
         
         or R 12  is a group of formula (II) and R 11  is a group of formula
   —[R 14 ] n —N(R 15 )-A-[N(R 15 ) 2 ] m    
 
         where 
         m is 0 or 1 and, when m is zero, A is a group of formula (II) and, when m is 1, A is alkylene or C 6 -C 10 arylene and R 15  is a group of formula (II). 
       
     
     
         12 . A composition according to  claim 11  comprising one or more triazole metal deactivators selected from the group consisting of 
       4-(or 5)-methyl-1-(di(2-ethylhexyl)-aminomethyl)-benzotriazole, 
       4-(or 5)-methyl-1-(dimethylaminomethyl)-benzotriazole, 
       4-(or 5)-methyl-1-(diethylaminomethyl)-benzotriazole, 
       4-(or 5)-methyl-1-(di-isopropylaminomethyl)-benzotriazole, 
       4-(or 5)-methyl-1-(di-n-butylaminomethyl)-benzotriazole, 
       4-(or 5)-methyl-1-(di-n-hexylaminomethyl)-benzotriazole, 
       4-(or 5)-methyl-1-(di-isooctylaminomethyl)-benzotriazole, 
       4-(or 5)-methyl-1-(di-n-octylaminomethyl)-benzotriazole, 
       4-(or 5)-methyl-1-(di-n-decylaminomethyl)-benzotriazole, 
       4-(or 5)-methyl-1-(di-n-dodecylaminomethyl)-benzotriazole, 
       4-(or 5)-methyl-1-(di-n-octadecylaminomethyl)-benzotriazole, 
       4-(or 5)-methyl-1-(di-n-eicosylaminomethyl)-benzotriazole, 
       4-(or 5)-methyl-1-[di-(prop-2′-enyl)aminomethyl]-benzotriazole, 
       4-(or 5)-methyl-1-[di-(but-2′-enyl)aminomethyl]-benzotriazole, 
       4-(or 5)-methyl-1-[di-(eicos-2′-enyl)aminomethyl]-benzotriazole, 
       4-(or 5)-methyl-1-(di-cyclohexylaminomethyl)-benzotriazole, 
       4-(or 5)-methyl-1-(di-benzylaminomethyl)-benzotriazole, 
       4-(or 5)-methyl-1-(di-phenylaminomethyl)-benzotriazole, 
       4-(or 5)-methyl-1-(4′-morpholinomethyl)-benzotriazole, 
       4-(or 5)-methyl-1-(1′-pyrrolidinomethyl)-benzotriazole, 
       4-(or 5)-methyl-1-(1′-piperidinomethyl)-benzotriazole, 
       4-(or 5)-methyl-1-(1′-perhydroroazepinomethyl)-benzotriazole, 
       4-(or 5)-methyl-1-(2′,2″-dihydroxyethyl)aminomethyl]-benzotriazole, 
       4-(or 5)-methyl-1-(dibutoxypropyl-aminomethyl)-benzotriazole, 
       4-(or 5)-methyl-1-(dibutylthiopropyl-aminomethyl)-benzotriazole and 4-(or 5)-methyl-1-(di-butylaminopropyl-aminomethyl)-benzotriazole. 
     
     
         13 . A composition according to  claim 11  comprising 4-(or 5)-methyl-1-(di(2-ethylhexyl)-aminomethyl)-benzotriazole or 4-(or 5)-methyl-1-(di-isooctylaminomethyl)-benzotriazole. 
     
     
         14 . A composition according to  claim 1  comprising
 one or more hindered phenolic antioxidants selected from the group consisting of 2,6-di-tert-butylphenol, 3,5-di-tert-butyl-4-hydroxyhydrocinnamic acid methyl ester and tetrakis-(3-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionyloxymethyl)methane and   one or more triazole metal deactivators selected from the group consisting of   
       1-(di-isooctylaminomethyl)-1,2,4-triazole, 1-(di-(2-ethylhexyl)aminomethyl) 1,2,4-triazole, 1-(2-methoxyprop-2-yl)tolyltriazole, 1-(1-cyclohexyloxypropyl)tolyltriazole, 1-(1-cyclohexyloxyheptyl)tolyltriazole, 1-(1-cyclohexyloxybutyl)tolyltriazole, 4-(or 5)-methyl-1-(di(2-ethylhexyl)-aminomethyl)-benzotriazole and 4-(or 5)-methyl-1-(di-isooctylaminomethyl)-benzotriazole. 
     
     
         15 . A composition according to  claim 1  further comprising one or more stabilizers selected from the group consisting of the 3-arylbenzofuranone stabilizers and the hindered amine light stabilizers. 
     
     
         16 . A composition according to  claim 1  where the components i) and ii) each are present at levels of about 5 ppm to about 5000 ppm. 
     
     
         17 . A composition according to  claim 1  where the components i) and ii) each are present at levels of about 50 ppm to about 5000 ppm. 
     
     
         18 . A process for the stabilization of a biodiesel fuel against the deleterious effects of heat, light, oxygen and metals, which process comprises
 incorporating into a biodiesel fuel   an effective stabilizing amount of a combination of   i) one or more compounds selected from the group consisting of the sterically hindered phenolic antioxidants and   ii) one or more compounds selected from the group consisting of the triazole metal deactivators.   
     
     
         19 . A composition according to  claim 1  further comprising one or more compounds selected from the group consisting of the metal chelating compounds.