Patent · US Expired

Composition and method for controlling precipitation when acidizing wells

US6225261A · kind A · utility

11Cited by
33References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 7, 1993
Grant dateMay 1, 2001
Priority date
Expiry dateJun 7, 2013

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S507/937
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

A composition and method for acidizing a formation in the presence of ferric ion, free sulfur and/or sulfides is disclosed. The composition employs a ferric ion reducing agent and a sulfide reactant separately or in combination. The ferric ion reducing agent is a thioalkyl acid. The sulfide reactant compounds include .alpha.-diketones and saturated and .alpha.-unsaturated cyclic ketones. In another aspect, the reducing activity of the thioalkyl acid is accelerated by the presence of a catalytic quantity of a compound or mixture of compounds which yield in acid solution cuprous ion, cupric ion or combinations thereof with iodide ion.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.