Conversion of aluminum-mercury amalgam and incidental mercury in contact with aluminum alloy surfaces to harmless compounds
AssigneeMobil Oil Corporation
InventorHoward L. Craig, Jr.
Life of this patent
Estimating the term…
Abstract
A method for treating mercury-contaminated aluminum surfaces to render aluminum-mercury amalgam and liquid mercury harmless to aluminum is provided. The method involves converting the mercury to a compound which is inert to aluminum, such as mercuric sulfide, at temperatures below the freezing point of water. This is accomplished by contacting the aluminum surface with a condensable solvent such as carbon disulfide, carbonyl sulfide, or tetrahydrofuran having gaseous hydrogen sulfide dissolved therein, and then dissolving a reactive gas such as sulfur dioxide within the solvent. The reaction of the two dissolved gases within the solvent generates the sulfur which reacts with the mercury to form mercuric sulfide.
Claims23
A method for treating a mercury-contaminated aluminum surface, comprising:
- (a) providing a liquid solvent which is substantially nonreactive with aluminum or mercury but capable of dissolving a sulfur-bearing component;
- (b) contacting said mercury-contaminated aluminum surface with said liquid solvent;
- (c) dissolving a sulfur-bearing component into said liquid solvent;
- (d) dissolving a gas reactive with said sulfur-bearing component into said solvent, said sulfur-bearing component and said gas reacting in such a manner that sulfur from said sulfur-bearing component reacts with the mercury upon said mercury-contaminated aluminum surface to render it inert to aluminum.
A method for rendering mercury and mercury amalgam present on an aluminum surface inert to aluminum, comprising:
- (a) depositing on said aluminum surface a liquid solvent capable of dissolving hydrogen sulfide;
- (b) contacting the resulting liquid solvent-wet surface with gaseous hydrogen sulfide;
- (c) contacting said solvent-wet aluminum surface with a reactant for releasing sulfur from hydrogen sulfide present in said liquid solvent, whereby said sulfur reacts with said mercury to form a compound inert to aluminum.
A method for rendering mercury and mercury amalgam present on an aluminum surface inert to aluminum, comprising:
- (a) providing a vaporized solvent having hydrogen sulfide dissolved therein;
- (b) condensing said vaporized solvent mixed with said dissolved hydrogen sulfide onto said aluminum surface;
- (c) contacting said solvent-wet aluminum surface with a gas capable of reacting with hydrogen sulfide and releasing sulfur therefrom, whereby said sulfur reacts with said mercury to form a compound inert to aluminum.
A method for treating a mercury-contaminated aluminum surface comprising:
- maintaining the temperature of said surface below about zero degrees Centigrade;
- providing a solvent capable of dissolving a sulfur-bearing component;
- contacting said surface with said solvent;
- dissolving a sulfur-bearing component within said solvent;
- and
- dissolving a substance reactive with said sulfur-bearing component in said solvent, said substance being capable of causing the release of sulfur from said sulfur-bearing component,
- whereby said sulfur reacts with said mercury to form mercuric sulfide.
Dependencies are inferred from the claim text.