Composition and method for controlling precipitation when acidizing wells
US5622919A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 13, 1995 |
| Grant date | Apr 22, 1997 |
| Priority date | — |
| Expiry date | Nov 13, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S585/95
- 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.