Method for treating hazardous and corrosion-inducing sulfur compounds

• US 6,652,660 B2
• Filed: 01/23/2003
• Issued: 11/25/2003
• Est. Priority Date: 09/19/2000
• Status: Expired due to Term

• Current Assignee: United Laboratories International, LLC (TriStar Global Energy Solutions, Inc.)
• Original Assignee: United Laboratories International, LLC (TriStar Global Energy Solutions, Inc.)
• Inventors: Frost, Jack G.
• Primary Examiner(s): GRIFFIN, WALTER DEAN
• Application Number:
  US10/349,647
• Publication Number:
  US 20030118470A1
• Time in Patent Office: 306 Days
• Field of Search: 422/7, 208/47, 585/950, 134/2, 148/240, 148/277, 423/544, 423/567.1
• US Class Current: 134/2
• CPC Class Codes: C01B 17/05 by wet processes
• CPC Class Codes: C01B 17/74 Preparation
• CPC Class Codes: C10G 27/12 with oxygen-generating compounds, e.g. per-compounds, chromic acid, chromates plumbites or plumbates C10G19/06
• CPC Class Codes: Y10S 585/95 Prevention or removal of corrosion or solid deposits

Abstract

A method for treating compounds which contain reactive sulfur is disclosed, wherein the treatment produces compounds which contain sulfur in a non reactive form. The method is based on the use of an oxidizing compound selected from the group consisting of water soluble inorganic persulfates, water soluble inorganic and organic adducts of hydrogen peroxide and mixtures thereof. The method is particularly useful in preventing stress corrosion cracking of stainless steel and in preventing auto-ignition of pyrophoric iron sulfide.

Claims

1. A method of decontaminating a closed vessel having an interior surface in contact with a first compound containing sulfur in a reactive form, said method being comprised of converting said first compound to a product selected from the group consisting of a second compound, elemental sulfur and mixtures thereof, wherein said second compound contains sulfur in a non-reactive form and is different from said first compound, the steps of said method comprising:

providing a closed vessel having an interior surface in contact with said first compound,

introducing into said closed vessel an aqueous solution comprising an effective quantity of an oxidizing agent,

establishing contact between said aqueous solution of said oxidizing agent and said first compound, and

maintaining said contact between said aqueous solution of said oxidizing agent and said first compound for a time sufficient to convert said first compound to said product;

said first compound is selected from the group consisting of water soluble compounds containing sulfur-to-sulfur bonds having an anion defined by the general structure

2. The method of claim 1 wherein said contact between said aqueous solution of said oxidizing agent and said first compound occurs at a temperature in the range of from about 150°

F. to about 190°

F. and the quantity of said oxidizing agent in said solution is an amount in the range of from about 500 to about 2000 parts of said oxidizing agent per million parts of said aqueous solution.

3. The method of claim 2 further comprising maintaining said quantity of said oxidizing agent in said aqueous solution at a value of at least about 500 parts of said oxidizing agent per million parts of said aqueous solution during said contact and terminating said contact after said quantity of said oxidizing agent remains constant for a time in the range of from about 1 to about 2 hours.

4. The method of claim 3 wherein the material of construction of said interior surface in contact with said first compound is susceptible to stress corrosion cracking.

5. The method of claim 4 wherein said material of construction is Austenitic steel.

6. The method of claim 4 wherein said water insoluble sulfides in said first compound are comprised of pyrophoric iron sulfide.

7. The method of claim 3 wherein said first compound is pyrophoric iron sulfide.