Patent ID: 6415865
Filing Date: 2002-07-09
Classification: C09K,Y10S

Abstract:
A method of treating a subterranean formation, comprising:contacting the formation with an acidizing composition, said acidizing composition including: a strong mineral acid solution selected from the group of: (a) an aqueous acid solution including at least about 25% by weight, based on the total weight of the solution, hydrochloric acid; and (b) an aqueous acid solution including a mixture of hydrochloric acid and one or more other acids, said hydrochloric acid and other acids being present in the solution in amounts sufficient for the solution to have an acid strength equal to or greater than the acid strength of an aqueous acid solution including about 25% by weight, based on the total weight of the solution, hydrochloric acid; an electron donor agent; and a primary electron transfer agent, said primary electron transfer agent being a source of rhenium ions; and a secondary electron transfer agent, said secondary electron transfer agent being selected from the group consisting of a source of iodide ion and an source of iodine, whereby said electron donor agent and said primary and secondary electron transfer agents function together to reduce ferric ion present in said aqueous mineral acid solution to ferrous ion.