Patent ID: 6526811
Filing Date: 2003-03-04
Classification: G01N

Abstract:
An analytical apparatus for measuring a low concentration of a constituent in a stream at a parts per billion level, comprising:(a) a sample loop having a predetermined volume for receiving a sample from the stream, the sample loop having an inlet for receiving a sample from the stream and an outlet; (b) a purifier for producing a substantially pure carrier liquid from a sample of the stream; (c) a first multi-path valve connected to the purifier and to the sample loop for alternately connecting the loop with a sample to be analyzed and with a purified carrier liquid from the purifier; (d) a preconcentrator column in fluid connection with the outlet of the sample loop for absorbing and increasing the concentration of the low concentration constituent; (e) a second multi-path valve connected to the preconcentrator column for alternately connecting the column with the carrier liquid containing the constituent and an eluent for the constituent; (f) a source of the eluent for the constituent, the source being connected to the second multi-path valve; and (g) a detector in fluid connection with the preconcentrator column for receiving and analyzing a constituent concentration in an eluent received from the preconcentrator column.