Detector for reference gas and oxydoreducing component comprises electrodes, in which potential difference across electrodes in atmosphere and reference gas is measured

摘要

Two containers (1, 5) are separated by a divider (4). One contains the atmosphere to be analyzed and two working electrodes (7, 8), one to detect the reference gas and the other the oxydoreducing component. The second contains a reference atmosphere and a reference electrode (6). The potential difference between the reference electrode and each working electrode is measured The first and second containers (1, 5) are separated by a divider (4) in a material which is electrically isolating and chemically inert. These containers are filled with the atmosphere to be analyzed and an atmosphere with a known content of the reference gas respectively. The reference electrode (6) is made of metal which can interact with the reference gas. This is placed in the second container near the divider. A first working electrode (7) made of the same metal as the reference electrode is placed in the first container near the divider and opposite a first part (6.1) of the reference electrode to form a condenser with it. The metal chosen has a low electrical sensitivity to the presence of the oxydoreduction component. A second working electrode (8) is made of a metal which can interact with the reference gas in a similar way to the other two electrodes and which is very sensitive to the presence of the oxydoreduction component. This second electrode is placed in the first container near the divider but spaced from the first electrode and opposite a second part of (6.2) the reference electrode to form a condenser with it. The electrodes are connected to means of measuring the voltage difference between the reference electrode and each of the working electrodes. The reference electrode and the first working electrode are made of platinum and the second working electrode is made of gold. The divider is made of quartz and is tubular. Each working electrode is made of a metallic wire wound round the external surface of the tube (4). The reference electrode has a long winding of metallic wire supported by an isolating carrier element (9) to extend in the longitudinal direction of the tube. Alternatively, the reference electrode has two windings on an isolating mandrel inside the tube of the divider, each extending relative to one working electrode. Alternatively, the reference electrode is a metal leaf rolled longitudinally on itself in the longitudinal direction of the tube and supported on its internal surface. The working electrodes are separated by a distance of about 60 times the distance separating each working electrode from the reference electrode.