Dionex ASE 150, Руководство оператора

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E • Theory of ASE
Doc. 065207-02 9/08
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E.2 Operation
ASE was first described in 1995 and 1996 (1–9). As a technique, it has grown
steadily in use since that time.
Figure E-1 shows a schematic of accelerated
solvent extraction.
To perform an extraction, the solid sample is loaded into a sample cell (1 to
100 mL), and the frit-containing end caps are tightened by hand onto the cells.
The filled sample cells are loaded into the oven for extraction and a collection
vessel (bottle or vial) is installed in the collection vessel holder. The oven is
maintained at the chosen operating temperature throughout the extraction (room
temperature to 200 °C). The cell design and associated fluid apparatus allow
operation of the extractions at elevated pressures (up to 1500 psi) to maintain the
solvents as liquids at temperatures above their boiling points. The temperature and
pressure are controlled independently for each cell regardless of the solvent used,
the moisture or mineral content of the sample, or any characteristic of the matrix
Figure E-1. Schematic of the ASE Process
Pump
Pressure
Relief
Valve
Static Valve
Waste
Bottle Collection
Vessel
Sample
Cell
Oven
Solvent
Bottle
Nitrogen
Purge Valve