Richard J Getz

US Patent:

50327216, Jul 16, 1991

Filed:

Jun 1, 1990

Appl. No.:

7/534701

Inventors:

Allan T. Bacon - Joppatowne MD
Julio Reategui - Hunt Valley MD
Richard C. Getz - Baltimore MD

Assignee:

Environmental Technologies Group, Inc. - Baltimore MD

International Classification:

H01J 4940

US Classification:

250282

Abstract:

An improved method for operating an ion mobility spectrometer (IMS) to enable detection of an acid gas analyte when air is used as the carrier gas and the drift gas in the IMS. A controlled concentration of a dopant substance is added to the air carrier gas stream prior to application of the carrier gas stream. In the IMS, the drift times of the ions generated from the doped air carrier gas differ from the drift times of the ions generated from the acid gas analyte, enabling the identification and quantification of the analyte. The dopants comprise substituted phenol compounds, with methyl salicylate (MS) or 2-hydroxyacetophenone (2-HAP) being preferred.

US Patent:

52831990, Feb 1, 1994

Filed:

Oct 18, 1991

Appl. No.:

7/778783

Inventors:

Allan T. Bacon - Joppatowne MD
Richard C. Getz - Baltimore MD

Assignee:

Environmental Technologies Group, Inc. - Baltimore MD

International Classification:

G01N 2400
B01D 5944

US Classification:

436173

Abstract:

An improved ion mobility spectrometer (IMS) and method for operating the same which enables analysis of chlorine dioxide in a mixture of gases which also includes the interferant chlorine. A controlled concentration of an amine such as methylamine is added to the air carrier gas stream prior to application of the carrier gas stream. The amine suppresses the chlorine peak, thereby improving the specificity of the IMS to chlorine dioxide. The IMS of the present invention also includes an improved membrane filter for pre-filtering chlorine, and a software algorithm for accommodating peak drift.