EP0109366A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method of decontaminating mineral oils and dielectric silicone fluids
Assignee: Delco Di Coppo Ingmario
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Filing: 1983-10-18
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Granted: —
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Expires: 2003-10-18
Abstract
Abstract The method comprises mixing the fluid to be decontaminated with a solvent at a temperature suitable for a full dissolution thereof, separating by decantation and/or centrifugation the solvent excess from the fluid under treatment, stripping the dissolved rests of solvent from the fluid and recovering the solvent by distillation under separation of the polychlorobiphenyl originally contained in the fluid to be decontaminated. A pyrrolidone or an alkylderivative thereof is employed as a solvent. The mixing, decantation and/or centrifugation and stripping steps can be cyclically repeated until the fluid is fully deconctaminated.
Inventors
- 👤 Mario Coppo
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-26 19:40
CPC Classifications
C; C10; C10G; C10G21/00; C10G21/006
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
79 words
Method of decontaminating mineral oils and dielectric silicone fluids from polychlorobiphenyl, characterized in that it comprised the steps of: - mixing the fluid to be contaminated with a suitable solvent at a suitable temperature in order to dissolve the polychlorobiphenyl and the possible oxidized compounds; - separating by decantation and/or centrifugation the solvent excess from the fluid under treatment, - stripping the dissolved rests of solvent from the fluid, - recovering the solvent by distillation and separating polychlorobiphenyl therefrom.
Claim 2
Dependent Claim
79 words
Method of decontaminating mineral oils and dielectric silicone fluids from polychlorobiphenyl, characterized in that it comprised the steps of: - mixing the fluid to be contaminated with a suitable solvent at a suitable temperature in order to dissolve the polychlorobiphenyl and the possible oxidized compounds; - separating by decantation and/or centrifugation the solvent excess from the fluid under treatment, - stripping the dissolved rests of solvent from the fluid, - recovering the solvent by distillation and separating polychlorobiphenyl therefrom.
Claim 3
Dependent Claim
36 words
Method as claimed in claim 1, characterized in that said dissolving step of polychlorobiphenyl and possible oxidized compounds contained in the fluid to be decontaminated occurs at a temperature ranging from 50° to 80 0 C.
Claim 4
Dependent Claim
27 words
Method as claimed in claim 1, characterized in that said stripping step is performed under vacuum . and in an atmosphere of inert gas, such as nitrogen.
Claim 5
Dependent Claim
29 words
Method as claimed in claim 1, characterized in that the mixing and dissolving, decantation and/or centrifugation and/or stripping steps are cyclically carried out until the fluid is fully decontaminated.
Claim 6
Dependent Claim
51 words
Method as claimed in claim 1, characterized in that said solvent is in a liquid condition at the operative temperature, in order to facilitate its mixing with the fluid to be decontaminated, said solvent further presenting a good heat-stability, a good water miscibility, a very small toxicity and a low cost.
Claim 7
Dependent Claim
48 words
Method as claimed in claim 1, characterized in that said solvent has a lower boiling temperature both than that of the fluid to be decontaminated and that of polychlorobiphenyl, in order that it can be readily recovered for reuse, said temperature being however higher than the working temperature.
Claim 8
Dependent Claim
32 words
Method as claimed in claim 1, characterized in that said solvent has a higher density than that of the fluid to be decontaminated in order to facilitate the decantation and/or centrifugation steps.
Claim 9
Dependent Claim
30 words
Method as claimed in anyone of the preceding claims, characterized in that a pyrrolidone or an alkylderivative thereof is employed as a solvent, such as 1-methyl ~ 2-pyrrolidone or 2-pyrrolidone.
References Cited (Backward Citations)
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