Inventors:
John E. Johnson - Lansdale PA
Mark Steinert - Shillington PA
Assignee:
JMIC, Inc. - Shillington PA
International Classification:
G01N 100
Abstract:
An analytical apparatus for measuring a low concentration of a constituent in a stream at a parts per billion level is provided. The apparatus comprises a sample loop having a predetermined volume for receiving a sample from the stream, a purifier for producing substantially pure carrier liquid from a sample of the stream, a first and a second multi-path valve, a preconcentrator column for absorbing and increasing the concentration of the low concentration constituent, an eluent, and a detector. In one embodiment, the apparatus is an ion chromatograph and may be used to analyze ions at concentrations as low as about 10 to about 1 part per billion. A method for analyzing a stream for a low concentration constituent present in a stream at a parts per billion level is also provided. The invention also includes methods for single- and multi-point calibration of a detector in an analytical apparatus for measuring a low concentration of a constituent in a stream at a parts per billion level.