Methods and compositions for biodistillate fuels containing tallow esters and having low metals uptake

Abstract

The invention relates to methods and compositions for attaining acceptably low uptake of zinc and copper metals in a renewable component of a distillate boiling range fuel composition. The method can advantageously comprise the steps of providing the renewable component comprising blending a tallow ester feed and at least one of soybean oil ester feed and palm oil ester feed, such that the tallow ester feed comprises from about 35 vol % to about 90 vol % of the renewable component, and exposing the renewable component blend to a source of zinc or copper under conditions sufficient for copper and/or zinc to leach into the renewable component, but only to an acceptably low level.

What is claimed is: 
     
         1 . A method of attaining acceptably low uptake of zinc and copper metals in a renewable component of a distillate boiling range fuel composition comprising:
 providing the renewable component comprising blending a tallow C 1 -C 4  alkyl ester feed and at least one of soybean oil C 1 -C 4  alkyl ester feed and palm oil C 1 -C 4  alkyl ester feed, such that the tallow C 1 -C 4  alkyl ester feed comprises from about 35 vol % to about 90 vol % of the renewable component; and   exposing the renewable component blend to a source of zinc or copper under conditions sufficient for copper and/or zinc to leach into the renewable component,   wherein the tallow C 1 -C 4  alkyl ester feed, by itself, exhibits a 24-hour uptake of zinc of at least about 1 ppm and a 24-hour uptake of copper of at least about 1 ppm, and wherein the renewable component blend exhibits a 24-hour uptake of copper and zinc of less than about 1 ppm combined.   
     
     
         2 . The method of  claim 1 , wherein the tallow C 1 -C 4  alkyl ester feed is tallow methyl ester (TME). 
     
     
         3 . The method of  claim 1 , wherein the soybean oil C 1 -C 4  alkyl ester feed is soybean oil methyl ester (SME). 
     
     
         4 . The method of  claim 1 , wherein the palm oil C 1 -C 4  alkyl ester feed is palm oil methyl ester (PME). 
     
     
         5 . The method of  claim 3 , wherein the renewable component comprises from about 5 vol % to about 65 vol % of soybean oil methyl ester (SME). 
     
     
         6 . The method of  claim 4 , wherein the renewable component comprises from about 5 vol % to about 65 vol % of palm oil methyl ester (PME). 
     
     
         7 . The method of  claim 2 , wherein the renewable component comprises from about 40 vol % to about 75 vol % of tallow methyl ester (TME). 
     
     
         8 . The method of  claim 7 , wherein the renewable component comprises from about 25 vol % to about 60 vol % of soybean oil methyl ester (SME). 
     
     
         9 . The method of  claim 7 , wherein the renewable component comprises from about 25 vol % to about 60 vol % of palm oil methyl ester (PME). 
     
     
         10 . The method of  claim 2 , wherein the renewable component comprises from about 40 vol % to about 60 vol % of tallow methyl ester (TME) and from about 40 vol % to about 60 vol % of soybean oil methyl ester (SME). 
     
     
         11 . The method of  claim 2 , wherein the renewable component comprises from about 40 vol % to about 60 vol % of tallow methyl ester (TME) and from about 40 vol % to about 60 vol % of palm oil methyl ester (PME). 
     
     
         12 . The method of  claim 1 , wherein the renewable component blend further exhibits one or more of the following characteristics:
 a 24-hour uptake of copper of less than about 0.70 ppm;   a 24-hour uptake of zinc of less than about 0.40 ppm; and   a 24-hour uptake of copper and zinc of less than about 0.80 ppm combined.   
     
     
         13 . The method of  claim 1 , wherein the renewable component blend further exhibits one or more of the following characteristics:
 a 24-hour uptake of copper of less than about 0.55 ppm;   a 24-hour uptake of zinc of less than about 0.30 ppm; and   a 24-hour uptake of copper and zinc of less than about 0.60 ppm combined.   
     
     
         14 . The method of  claim 1 , further comprising blending from about 5 vol % to about 25 vol % of the renewable component with from about 60 vol % to about 95 vol % of a diesel boiling range non-renewable component to attain a diesel fuel composition with acceptably low copper and/or zinc metal uptake characteristics. 
     
     
         15 . The method of  claim 14 , wherein the diesel boiling range component exhibits at least two of the following characteristics:
 an initial boiling point of at least about 215° F. (about 102° C.);   a final boiling point of about 800° F. (about 427° C.) or less;   a T5 boiling point of at least about 275° F. (about 135° C.); and   a T95 boiling point of about 775° F. (about 418° C.) or less.   
     
     
         16 . The method of  claim 14 , wherein the diesel boiling range component has boiling range from about 451° F. (about 233° C.) to about 800° C. (about 427° C.). 
     
     
         17 . The method of  claim 14 , wherein the diesel fuel composition exhibits at least two of the following characteristics:
 an initial boiling point of at least about 215° F. (about 102° C.);   a final boiling point of about 800° F. (about 427° C.) or less;   a T5 boiling point of at least about 275° F. (about 135° C.); and   a T95 boiling point of about 775° F. (about 418° C.) or less.   
     
     
         18 . The method of  claim 1 , further comprising blending from about 45 vol % to about 85 vol % of the renewable component with from about 15 vol % to about 55 vol % of a diesel boiling range non-renewable component to attain a diesel fuel composition with acceptably low copper and/or zinc metal uptake characteristics. 
     
     
         19 . The method of  claim 18 , wherein the diesel boiling range component exhibits at least two of the following characteristics:
 an initial boiling point of at least about 215° F. (about 102° C.);   a final boiling point of about 800° F. (about 427° C.) or less;   a T5 boiling point of at least about 275° F. (about 135° C.); and   a T95 boiling point of about 775° F. (about 418° C.) or less.   
     
     
         20 . The method of  claim 18 , wherein the diesel fuel composition exhibits at least two of the following characteristics:
 an initial boiling point of at least about 215° F. (about 102° C.);   a final boiling point of about 800° F. (about 427° C.) or less;   a T5 boiling point of at least about 275° F. (about 135° C.); and   a T95 boiling point of about 775° F. (about 418° C.) or less.