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:
Jan. 31, 1978
Filed:
Jan. 30, 1976
Michel Senes, La Baule, FR;
Yannick Le Goff, Saint Nazaire, FR;
Jean-Francois Gourdier, Saint Nazaire, FR;
Abstract
The invention relates to the purification of gaseous effluents containing ides of nitrogen by reduction of said oxides in the presence of a catalyst at raised temperatures. The catalysts used in this process contain iron as a major constituent, and may contain chromium or vanadium: these constitute 96 to 99.5% of the weight of the catalyst. Also present as promoters, in a total amount of 4.0 to 0.5% by weight of the catalyst, are one or more rare earth metal oxides and a trace quantity of a platinum metal. The catalyst is prepared by a method which ensures a specific surface of 20-100 m.sup.2 /g and pores having a maximum dimension between 100 and 5000 A. Such a catalyst is particularly suitable for removing residual oxides of nitrogen from the gaseous effluent obtained in the production of nitric acid by the oxidation of ammonia.