Patent ID: 7629298

Claim:
A method for modifying the wettability of sandstone, the method comprising applying a chemical formulation to sandstone, the sandstone bearing at least one of oil or gas, and the chemical formulation comprising: a polar organic solvent, water, a fluorochemical represented by the formula: R f SO 2 —N(R)(C n H 2n )CHZ(C m H 2m )N(R′)SO 2 R f wherein each R f is independently —C p F 2p+1 , where p is an integer from 2 to 5; R is selected from the group consisting of an aryl group and a C 1 to C 6 alkyl group; m and n are each independently integers from 1 to 20; Z is selected from the group consisting of —H and a group having the formula —(C t H 2t )—X-Q-Si(Y′) w (Y) 3−w , in which t is an integer from 0 to 4; —X— is selected from the group consisting of —O—, —S— and —NH—; -Q- is selected from the group consisting of —C(O)NH—(CH 2 ) v — and —(CH 2 ) v —; v is an integer from 1 to 20; Y is a hydrolyzable group; Y′ is a non-hydrolyzable group; and w is an integer from 0 to 2; and R′ is selected from R and a group represented by the formula —(CH 2 ) v —Si(Y′) w (Y) 3−w , with the proviso that when Z is —H, R′ is a group represented by the formula —(CH 2 ) v —Si(Y′) w (Y) 3−w ; and a hydrolysis catalyst for hydrolyzing the Si—Y bond, the hydrolysis catalyst comprising one of an acid compound or alkaline compound.