Organosulfonyl Latent Acids for Petroleum Well Acidizing

Abstract

Oil wells are treated with latent acids containing a sulfonyl moiety, wherein the latent acid is capable of providing an active acid after injection into an oil well. The latent acids are converted to active acids, such as mineral acids or strong organic acids, in the oil well, with resultant dissolution of acid-soluble minerals that impede oil or gas flow. RYSO2X is an exemplary latent acid, where: R is C(1)-C(30) hydrocaryl alone, or appended to an oligomeric or polymeric chain, or substituted; X is halogen; and Y is O, S, Se, or NR or a direct bond. M is a Group IVA metal, a Group IVB metal, a Group IB metal, or a Group HB metal. Other exemplary latent acids include amine functionality.

1 . A method of treating an oil well, comprising injecting into the well a composition comprising a latent acid comprising a sulfonyl moiety, wherein the latent acid is capable of providing an active acid after injection into an oil well. 
     
     
         2 . The method of  claim 1 , wherein the latent acid is a sulfonyl halide, sulfonate ester, sulfonamide, or thiolsulfonate. 
     
     
         3 . The method of  claim 1 , wherein the latent acid is a thiolsulfonate, the method further comprising injecting into the well an oxidizing agent. 
     
     
         4 . The method of  claim 1 , wherein the latent acid is an ester, amide, or acid halide of methanesulfonic acid. 
     
     
         5 . The method of  claim 1 , wherein the composition further comprises a nucleophile. 
     
     
         6 . The method of  claim 1 , wherein the step of injecting the composition comprises injecting it into strata in the well having a temperature from 20 to 250° C. 
     
     
         7 . The method of  claim 1 , wherein the step of injecting the composition comprises injecting it into strata in the well having a temperature from 50 to 150° C. 
     
     
         8 . The method of  claim 1 , wherein the latent acid is according to any of formulas (I), (II), and (III)
   R 1 YSO 2 X   (I)     R 1 YSO 3   −+ NHR 2 R 3 R 4    (II)     (R 1 YSO 3 ) p (OR 2 ) q (NR 3 R 4 ) r M   (III)   
       wherein R 1  is selected from the group consisting of C 1 -C 30  hydrocarbyl moieties, C 1 -C 30  hydrocarbyl moieties appended to an oligomeric or polymeric chain, and C 1 -C 30  hydrocarbyl moieties substituted with functional groups containing halogen, oxygen, sulfur, selenium, silicon, tin, lead, nitrogen, phosphorous, antimony, bismuth, aluminum, boron, or metals selected from Groups IA-IIA and IB-VIIIB of the periodic table; X is a halogen or ZCR 2 R 3 R 4 ; Y and Z are independently O, S, Se, or NR 5 , and Y may also be a direct bond; R 2 , R 3 , R 4  and R 5  are independently hydrogen or as defined for R 1  and wherein any two or more of R 1 , R 2 , R 3 , R 4  and R 5  may be interconnected to form one or more cyclic structures; M is a Group IVA metal, a Group IVB metal, a Group IB metal, or a Group IIB metal; and p+q+r=n wherein n is the valence of metal M. 
     
     
         9 . The method of  claim 8 , wherein the step of injecting the composition comprises injecting it into strata in the well containing predominately silica-containing rock, and wherein the latent acid comprises R 1 SO 2 F or R 1 YSO 2 F. 
     
     
         10 . The method of  claim 8 , wherein the composition further comprises HCl or HF. 
     
     
         11 . The method of  claim 8 , wherein the step of injecting the composition comprises injecting it into strata in the well containing predominately silica-containing rock, wherein the latent acid comprises R 1 SO 2 Cl or R 1 YSO 2 Cl, and wherein the composition further comprises sodium fluoride, potassium fluoride, or barium fluoride. 
     
     
         12 . The method of  claim 11 , wherein the composition further comprises HCl or HF. 
     
     
         13 . The method of  claim 8 , wherein R 1  is a C 1 -C 30  hydrocarbyl moiety and each of R 2 , R 3 , R 4  and R 5  is independently hydrogen or a C 1 -C 30  hydrocarbyl moiety. 
     
     
         14 . The method of  claim 8 , wherein R 1  is a C 1 -C 30  hydrocarbyl moiety substituted with a functional group containing halogen, oxygen, sulfur, nitrogen, silicon, or phosphorus, and wherein each of R 2 , R 3 , R 4  and R 5  is independently hydrogen or a C 1 -C 30  hydrocarbyl moiety substituted with a functional group containing halogen, oxygen, sulfur, nitrogen, silicon, or phosphorus. 
     
     
         15 . The method of  claim 8 , wherein X is Cl. 
     
     
         16 . The method of  claim 8 , wherein X is O-n-butyl or O-sec-butyl. 
     
     
         17 . The method of  claim 8 , wherein X is O-n-octyl. 
     
     
         18 . The method of  claim 8 , wherein X is O-2-ethylhexyl.