Water-based formulation of h2s/mercaptan scavenger for fluids in oilfield and refinery applications

Abstract

Hydrogen sulfide (H 2 S) and/or mercaptan scavengers are chemicals that remove H 2 S and/or mercaptans from gas, oil and water. Water-based formulations may be made and used employing scavenging compounds having the formulae: wherein each R 1 , R 2 , R 3 , and R 4 are the same or different and are selected from the group consisting of hydrogen, an alkyl, an alkenyl, an aryl, an acyl, a halogen, a hydroxyl, a nitro, an alkyl ester, an aryl ester, an alkyl ether, an aryl ether, a hydroxymethyl, an anhydride group, an amino, and a sulfide. In one non-limiting embodiment the compounds (A) and (B) do not contain nitrogen atoms. Water-based formulations, such as those using a protic solvent with the above compounds, work well as H 2 S scavengers.

What is claimed is: 
     
         1 . A protic composition for treating fluids containing hydrogen sulfide comprising:
 a protic solvent;   optionally a base selected from the group consisting of sodium hydroxide, potassium hydroxide and combinations thereof; and   a non-nitrogen-based compound having a formula selected from the group consisting of:   
       
         
           
           
               
               
           
         
       
       wherein each R 1 , R 2 , R 3 , and R 4  are the same or different and are selected from the group consisting of hydrogen, an alkyl, an alkenyl, an aryl, an acyl, a halogen, a hydroxyl, an alkyl ester, an aryl ester, an alkyl ether, an aryl ether, a hydroxymethyl, an anhydride, and a sulfide, where the protic composition reduces the amount of hydrogen sulfide in the fluid as compared to an identical method absent the protic composition, where the fluid is selected from the group consisting of:
 an aqueous phase, 
 a gaseous phase, 
 a mixture of an aqueous phase and a gaseous phase, 
 a mixture of an aqueous phase and a hydrocarbon phase, and 
 a mixture of an aqueous phase, a gaseous phase and a hydrocarbon phase. 
 
     
     
         2 . The protic composition of  claim 1  having a pH of greater than 9. 
     
     
         3 . The protic composition of  claim 1  having a pH of from about 11 to about 13. 
     
     
         4 . The protic composition of  claim 1  comprising a base selected from the group consisting of sodium hydroxide, potassium hydroxide and combinations thereof, the base being present at a concentration effective to give the composition a pH of greater than 9. 
     
     
         5 . The protic composition of  claim 1  where the protic solvent is selected from the group consisting of water, alcohols, glycols, and combinations thereof. 
     
     
         6 . The protic composition of  claim 1  where the non-nitrogen-based compound is present in the protic composition at a concentration of from about 50 to about 1000 ppm. 
     
     
         7 . A protic composition for treating fluids containing hydrogen sulfide comprising:
 a protic solvent selected from the group consisting of water, alcohols, glycols, and combinations thereof;   optionally a base selected from the group consisting of sodium hydroxide, potassium hydroxide and combinations thereof; and   from about 50 to about 1000 ppm present in the protic composition of a non-nitrogen-based compound having a formula selected from the group consisting of:   
       
         
           
           
               
               
           
         
       
       wherein each R 1 , R 2 , R 3 , and R 4  are the same or different and are selected from the group consisting of hydrogen, an alkyl, an alkenyl, an aryl, an acyl, a halogen, a hydroxyl, an alkyl ester, an aryl ester, an alkyl ether, an aryl ether, a hydroxymethyl, an anhydride, and a sulfide, where the protic composition reduces the amount of hydrogen sulfide in the fluid as compared to an identical method absent the protic composition, where the fluid is selected from the group consisting of:
 an aqueous phase, 
 a gaseous phase, 
 a mixture of an aqueous phase and a gaseous phase, 
 a mixture of an aqueous phase and a hydrocarbon phase, and 
 a mixture of an aqueous phase, a gaseous phase and a hydrocarbon phase; and 
 
       where the protic composition has a pH of greater than 9. 
     
     
         8 . The protic composition of  claim 7  having a pH of from about 11 to about 13. 
     
     
         9 . The protic composition of  claim 7  comprising a base selected from the group consisting of sodium hydroxide, potassium hydroxide and combinations thereof, the base being present at a concentration effective to give the composition a pH of greater than 9. 
     
     
         10 . A protic composition for treating fluids containing hydrogen sulfide comprising:
 a protic solvent;   a base selected from the group consisting of sodium hydroxide, potassium hydroxide and combinations thereof; and   a non-nitrogen-based compound having a formula selected from the group consisting of:   
       
         
           
           
               
               
           
         
       
       wherein each R 1 , R 2 , R 3 , and R 4  are the same or different and are selected from the group consisting of hydrogen, an alkyl, an alkenyl, an aryl, an acyl, a halogen, a hydroxyl, an alkyl ester, an aryl ester, an alkyl ether, an aryl ether, a hydroxymethyl, an anhydride, and a sulfide, where the protic composition reduces the amount of hydrogen sulfide in the fluid as compared to an identical method absent the protic composition, where the fluid is selected from the group consisting of:
 an aqueous phase, 
 a gaseous phase, 
 a mixture of an aqueous phase and a gaseous phase, 
 a mixture of an aqueous phase and a hydrocarbon phase, and 
 a mixture of an aqueous phase, a gaseous phase and a hydrocarbon phase; and 
 
       the protic composition having a pH of from about 11 to about 13. 
     
     
         11 . The protic composition of  claim 10  comprising a base at a concentration effective to give the composition a pH of greater than 9. 
     
     
         12 . The protic composition of  claim 10  where the protic solvent is selected from the group consisting of water, alcohols, glycols, and combinations thereof. 
     
     
         13 . The protic composition of  claim 10  where the non-nitrogen-based compound is present in the protic composition at a concentration of from about 50 to about 1000 ppm.