| abstract |
Ferric iron contained in a fracturing fluid is prevented from precipitating or otherwise disadvantageously reacting by adding a thioalkyl acid compound to the fracturing fluid. The thioalkyl acid compound reduces ferric ion to ferrous ion which remains in solution at pH levels below about 7.5. The thioalkyl acid compound has the formula:n n where n is an integer from 1 to 10; Z is R or M; R is hydrogen, -(CH₂) x CH₃,-CH₂COOH or -(CH₂) x C₆H₅ wherein x is 0 or an integer from 1 to 6; M is sodium, potassium, ammonium, calcium, magnesium or H₃N⁺OH; and d is 1 when Z is R, or d is 1 or 2 when Z is M to match the valence of M. |