Abstract: An electrochemical detection cell (320), which is usable either for potentiometric or electrolytic conductivity detection, has a capillary (305), which controls electrolyte flow. A gas stream containing detectable substances is input through a non-wettable plastic capillary (306). A reaction zone (310) through which both gas and liquid flow is internally wettable. Reference electrode (309) and either electrode (311) or (312) may be used for potentiometric detection. Sensor electrodes (311) and (312), both in the reaction zone, are used for conductivity detection. The electrolyte is fed through the capillary (305) gravimetrically from a reservoir, and the gas stream is supplied by a pyrolysis furnace. The mechanism of ionization in the gas phase ionization detector (GPELCD) is described.

Abstract: A detector system (10) especially suited for detecting a halogen containing component in a gas stream includes a gas chromatograph (12), which is connected by gas line (13) to pyrolysis chamber (14). Sources (16) of additional gas streams are connected by a gas line (18) to the pyrolysis chamber (14). The detector electrodes in the pyrolysis chamber (14) are electrically connected to detector electronics (20) by line (22). A temperature control circuit (24) is electrically connected to heater (26) by line (28). Heater (26) is thermally coupled to the pyrolysis chamber (b 14) at (30). The pyrolysis chamber (14) is thermally coupled to thermocouple (32) at (34). The thermocouple (32) is electrically connected to the temperature control circuit (24) by line (36). The heater (26) is independent of the detector electrodes and maintains a temperature between about 700 degrees and 1000 degrees Centigrade. The detector electrodes are substantially alkali metal free.

Abstract: An electrochemical detector cell (10) and apparatus incorporating the cell (10) includes a first capillary (12) having an entrance (14) connected to an electrolyte source (30) and an exit (16). A second capillary (18) is connected to reactive gas source (32) and intersects the first capillary (12) at (22) to define a reaction zone (20) in the first capillary (12). A sensor electrode (24) is positioned in the first capillary (12) in the reaction zone (20). A third capillary (26) intersects the first capillary (12) within the reaction zone (20). A reference electrode (28) is positioned in the third capillary (26). The third capillary (26) is connected to a solution source (34). The electrodes (24) and (28) may be used for potentiometric measurements. A fourth capillary (38) intersects the first capillary between entrance (14) and intersection (22) of the first capillary (12) and the second capillary (18).