APPROACHES TO IN-LINE REMOVAL OF DISSOLVED-OXYGEN IN FLOW SYSTEMS FORPROCESS ANALYSIS

Two methods for the removal of oxygen in analytical flow systems are d escribed. Efficient deoxygenation can be realized by introducing N-2 i nto the stream to form a two-phase flow combined with a membrane gas-l iquid separator. A similar effect can be obtained by passing the flow through a length of Poreflon membrane tubing placed in a water bath at 100 degrees C. These methods are simple and rapid and remove more tha n 98% of the oxygen originally present. In order to evaluate the effic iencies of oxygen removal by these methods, we developed a reversed (r eagent injection)-FIA system utilizing pyrogallol for spectrophotometr ic oxygen determination.