Patent · US Expired

Method of calibration using analytical apparatus for measurement of low concentration constituent

US6679093B2 · kind B2 · utility

6Cited by
5References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 17, 2002
Grant dateJan 20, 2004
Priority date
Expiry dateOct 17, 2022

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N2030/965
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

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 1 to about 500 parts per trillion. 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.

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