Methods and Compositions for Removing Residues and Substances from Substrates Using Environmentally Friendly Solvents

Abstract

Environmentally friendly solvents used to dissolve or remove residues and/or substances from substrates wherein the residue and/or substance is contacted with a Generally Recognized As Safe solvent to dissolve the residue and/or substance in the solvent followed by the extraction of the residue and/or substance from the solvent such as by contact with carbon dioxide.

1 . A method for determining the percent of bitumen present in a petroleum residue sample, said method comprising: 
     contacting the petroleum residue sample with an ester-containing solvent to remove the bitumen therefrom, and wherein the weight of the bitumen in the sample is determined by comparing the initial weight of the petroleum residue and the weight of a remaining portion of the petroleum residue. 
   
   
       2 . The method according to  claim 1 , wherein the petroleum residue comprises bitumen and inorganic material, and wherein the inorganic material remains subsequent to said step of contacting the petroleum residue sample with an ester-containing solvent, said method further comprising contacting the inorganic material at least once with an organic solvent. 
   
   
       3 . The method according to  claim 2  wherein the organic solvent is a C1-C4 alcohol 
   
   
       4 . The method according to  claim 3  wherein the organic solvent is ethanol. 
   
   
       5 . The method according to  claim 4  wherein the petroleum residue is an asphalt residue 
   
   
       6 . The method according to  1 , further comprising the step of contacting the ester containing solvent with a fluid comprising carbon dioxide, wherein the petroleum residue is recovered in the fluid such that the ester containing solvent is separated from the petroleum residue.