Solvents and compositions for treating hydrocarbon-bearing formations

A method of treating a hydrocarbon-bearing formation, the method comprising:

• receiving data comprising a temperature and a brine composition of the hydrocarbon-bearing formation;
• selecting a treatment composition for the hydrocarbon-bearing formation comprising a fluorinated compound and solvent comprising at least one of a ketone, ester, ether, each having from 4 to 10 carbon atoms, or a hydrofluoroether or hydrofluorocarbon, wherein, at the temperature, a mixture of an amount of the brine composition and the treatment composition separates into at least two separate transparent liquid layers, and wherein the mixture is free of precipitated solid;
• and
• contacting the hydrocarbon-bearing formation with the treatment composition.

A composition comprising solvent and one of a fluorinated polymer or a fluorinated polyurethane with at least two repeat units,

• the fluorinated polymer comprising:
• at least one divalent unit represented by formula:
• and at least one unit selected from the group consisting of:
• wherein
• Rf1 represents a perfluoroalkyl group having up to 8 carbon atoms;
• R, R1, R2, and R3 are each independently selected from the group consisting of hydrogen and alkyl having up to 4 carbon atoms;
• m is an integer from 1 to 11;
• EO represents —CH2CH2O—;
• each R4O is independently selected from the group consisting of —CH(CH3)CH2O—, —CH2CH2CH2O—, —CH2CH(CH3)O—, —CH(CH2CH3)CH2O—, —CH2CH(CH2CH3)O—, and —CH2C(CH3)2O—;
• each p is independently 1 to 150;
• and
• each q is independently 0 to 55;
• the fluorinated polyurethane comprising:
• at least one end group represented by the formula
• —NH—C(O)—O—(CjH2j)N(R″)S(O)2—Rf2;
• and
• at least one end rou represented b the formula —NH—CHkH2k)—SiG′3;
• wherein
• each Rf2 independently represents perfluoroalkyl having from 2 to 6 carbon atoms;
• each R″ is independently hydrogen or alkyl having up to four carbon atoms;
• each G′ is independently alkoxy or hydroxyl;
• and
• j and k are each independently values from 1 to 6;
• and the solvent comprising:
• water in a range from 5 to 40 percent by weight, based on the total weight of the composition;
• a monohydroxy alcohol having up to 4 carbon atoms in a range from 25 to 60 percent by weight, based on the total weight of the composition;
• and
• a ketone having from 4 to 10 carbon atoms in a range from 15 to 60 percent by weight, based on the total weight of the composition.