Patent · US Expired

Process and apparatus for measuring gaseous fixed nitrogen species

US4333735A · kind A · utility

487Cited by
4References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 16, 1981
Grant dateJun 8, 1982
Priority date
Expiry dateMar 16, 2001

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T436/176152
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Process and apparatus for measuring total fixed gaseous nitrogen species, including NH.sub.3, NO, NO.sub.2, HCN and organic amines in gaseous mixtures. The process involves catalytic conversion at elevated temperature of all fixed nitrogen species to nitric oxide, NO, followed by chemiluminescent measurement of the resulting NO concentration. The improvement features of the process are the use of a reduced pressure gaseous sample flow to prevent N.sub.2 poisoning of the heated platinum catalyst and a preheat step of the reduced pressure gaseous mixture in an inert, non-catalytic quartz preheater prior to catalytic conversion to prevent loss of some species, such as NH.sub.3, through premature catalyzed reaction with NO and subsequent loss from the system as N.sub.2.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.