Method of Reducing Fuel Corrosiveness

Abstract

Fuels containing biodiesel, petroleum distillates, or blends of these may be treated by the addition of small amounts of one or more alkanolamines according to formula (I) R n —N(CH 2 CHR 1 OH) 3-n ;   (I) wherein n is 1 or 2, R 1 is H or CH 3 , and each R is independently selected from the group consisting of hydrogen and branched, linear, and cyclic C3-C24 alkyl groups, provided that at least one R is not hydrogen. Fuels treated in this manner may be less corrosive toward metals with which they are in contact.

1 . A treated fuel comprising:
 a) an untreated fuel consisting of a biodiesel, a petroleum distillate, or a blend thereof; and   b) one or more alkanolamines according to formula (I)
   R n —N(CH 2 CHR 1 OH) 3-n    (I); 
   wherein n is 1 or 2, R 1  is H or CH 3 , and each R is independently selected from the group consisting of hydrogen and branched, linear, and cyclic C3-C24 alkyl groups, provided that at least one R is not hydrogen, and wherein the treated fuel is essentially free of added biological control agents.   
     
     
         2 . The treated fuel of  claim 1 , wherein the treated fuel comprises less than 2 wt % water. 
     
     
         3 . The treated fuel of  claim 1 , wherein the treated fuel further comprises from 2 to 25 wt % water. 
     
     
         4 . The treated fuel of  claim 1 , wherein the untreated fuel consists of said blend and wherein the biodiesel constitutes at least about 5 wt % of the blend. 
     
     
         5 . The treated fuel of  claim 1 , wherein the untreated fuel consists of said blend and wherein the biodiesel constitutes at least about 20 wt % of the blend. 
     
     
         6 . The treated fuel of  claim 1 , wherein the untreated fuel consists of said blend and wherein the biodiesel constitutes at least about 80 wt % of the blend. 
     
     
         7 . The treated fuel of  claim 1 , wherein the untreated fuel consists of the biodiesel. 
     
     
         8 . The treated fuel of  claim 1 , wherein the untreated fuel consists of the petroleum distillate. 
     
     
         9 . The treated fuel of  claim 1 , wherein the biodiesel or the petroleum distillate comprises one or more fatty or naphthenic acid impurities, or both, and wherein the one or more alkanolamines of formula (I) are present in an amount equal to at least 0.8 mol equivalents relative to a total of the fatty and naphthenic acid impurities. 
     
     
         10 . The treated fuel of  claim 1 , wherein the one or more alkanolamines of formula (I) are present in an amount equal to from 0.01 to 2 wt % relative to the untreated fuel. 
     
     
         11 . The treated fuel of  claim 1 , wherein corrosion of brass in the presence of the treated fuel produces less than 70 ppm of copper in the treated fuel. 
     
     
         12 . The treated fuel of  claim 1 , wherein the biodiesel or the petroleum distillate comprises one or more fatty or naphthenic acid impurities, or both, and wherein the biodiesel comprises from 0.01 to 5 wt % of the fatty acid impurities. 
     
     
         13 . The treated fuel of  claim 1 , wherein the untreated fuel consists of said blend. 
     
     
         14 . The treated fuel of  claim 1 , wherein the petroleum distillate comprises No. 2 fuel oil. 
     
     
         15 . The treated fuel of  claim 1 , wherein the petroleum distillate comprises a jet fuel. 
     
     
         16 . The treated fuel of  claim 1 , wherein the biodiesel or the petroleum distillate comprises one or more fatty or naphthenic acid impurities, or both, and wherein the petroleum distillate comprises from 0.01 to 1 wt % of the naphthenic acid impurities. 
     
     
         17 . The treated fuel of  claim 1 , wherein a total number of carbon atoms in the R groups is from 4 to 24. 
     
     
         18 . The treated fuel of  claim 1 , wherein a total number of carbon atoms in the R groups is from 6 to 20. 
     
     
         19 . A method of treating a fuel, comprising blending together:
 a) an untreated fuel consisting of a biodiesel, a petroleum distillate, or a blend thereof; and   b) one or more alkanolamines according to formula (I)
   R n —N(CH 2 CHR 1 OH) 3-n    (I); 
   wherein n is 1 or 2, R 1  is H or CH 3 , and each R is independently selected from the group consisting of hydrogen and branched, linear, and cyclic C3-C24 alkyl groups, provided that at least one R is not hydrogen, and wherein the treated fuel is essentially free of added biological control agents.   
     
     
         20 . The method of  claim 19 , wherein the blending is performed at a temperature from 10 to 50° C. 
     
     
         21 . The method of  claim 19 , further comprising blending from 2 to 25 wt % of water, based on the total weight of the resulting mixture, with any of the biodiesel, the petroleum distillates, the untreated fuel, or the treated fuel.