The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 04, 2001
Filed:
Nov. 10, 1998
Robert N. O'Brien, Victoria, B.C., CA;
Other;
Abstract
Methods for concentrating nitric acid in aqueous solution are known wherein reduction of some nitric acid initially present in the solution oxidizes nitric oxide obtained for example from exhaust vapors of heterogneously catalytically combusted ammonia, but gas effluence and solution dilution associated with such methods have necessitated recirculation piping to convey fluids of varying content to and fro between separated reactor units adapted to conduct different sub-reactions subsumed under an overall process which is inherently unworkable in batch mode operations. Herein the invention features joint execution of all necessary reactions in a single reactive solution body, and resorts to a liquid phase homogeneous catalysis involving nitrate and/or nitrosyl ions, in a process which is effective whether in continuous or batch processing. Problems with low gas solubilities and diffusivities are resolved when a high enough Hatta Number is attained due to fast free radical-ion reactions in the vicinity of gas-liquid interfaces provided by gas-filled bubbles. Reaction control means include varying the proportion and/or concentration of sulfuric acid blended with nitric acid to constitute a catalytic solution.