Use of high purity imidazoline based amphoacetate surfactant as foaming agent in oil wells
US5614473A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 22, 1995 |
| Grant date | Mar 25, 1997 |
| Priority date | — |
| Expiry date | May 22, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K8/594
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Increased foam quality and resistance to hydrocarbon defoaming for foams used in well boring and stimulation processes as well as secondary and tertiary oil recovery is obtained using imidazoline-based amphoacetates of higher purity, containing essentially negligible amounts of unalkylated amido amines, lower amounts of glycolic acid salts and monochloroacetate salts. The higher purity amphoacetates can be obtained via processes utilizing precise pH control during the reaction of imidazoline, or its open-chain derivatives, with alkylating agents, e.g. sodium monochloroacetate. These higher-purity amphoacetates contain essentially fully alkylated products and lower amounts of glycolic acid derivatives, even though a ratio of monohaloalkylate to substituted imidazoline, or its open-ring derivative, of less than 1.5:1.0 and close to 1.0:1.0 is used.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.