Process for quantitatively converting urea to ammonia on demand

Patent 6761868 Issued on July 13, 2004. Estimated Expiration Date:

September 12, 2021. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

3826815

3900554

3922222

Method of hydrolyzing urea contained in waste water streams
Patent #: 4087513
Issued on: 05/02/1978
Inventor: Schell

Catalytic method for hydrolyzing urea
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Catalytic method for hydrolyzing urea
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Process for the purification of urea solutions containing biuret and the like
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Inventors

Assignee

The Chemithon Corporation

Application

No. 09951287 filed on 09/12/2001

US Classes:

423/358, From organic material containing nitrogen423/235Nitrogen or nitrogenous component

Examiners

Primary: Langel, Wayne A.

Attorney, Agent or Firm

Marshall, Gerstein & Borun LLP

Foreign Patent References

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International Class

C01C 108

Abstract

Processes and apparatus for quantitatively converting urea to ammonia on demand are disclosed. One process includes the steps of: receiving a demand rate signal for ammonia; feeding reactants including urea and water into a reactor to provide a reaction mixture; and controlling temperature and pressure in the reactor to produce a gaseous product stream including ammonia and carbon dioxide at substantially constant concentrations. Another process includes the steps of: feeding molten urea or solid urea to a reactor; feeding water (liquid or steam) to the reactor; and reacting the urea and water at elevated temperature and pressure to form a gaseous product stream including ammonia and carbon dioxide.

Other References

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