COMPOSITE ELECTRODE FOR MEASURING PH OF HIGH-TEMPERATURE HIGH-PRESSURE AQUEOUS SOLUTION

摘要

PURPOSE:To obtain the composite electrode which is chemically stable and has a wide measurable temp. range and fast response speed by providing an oxide semiconductor sensing electrode part, a counter electrode part and a reference electrode part to the inside wall side of an insulating holder which is hollow and is open on one side. CONSTITUTION:Apertures 2-4 are provided to an insulating holder 1 and the oxide semiconductor pH sensing electrode 5 is held in the aperture 2 via an O-ring 7 in a cylinder 6 by positioning the electrode toward the inside wall side of the insulating holder. The reference electrode body 14 is fixed in the aperture 3 and a liquid permeable solid 15 is fixed to the inside wall surface side. An ion-permeable high-polymer film 16 is installed in the pipeline from the aperture 3 and an internal liquid 17 for the reference electrode is packed therein. Further, the counter electrode 28 made of an inert metal is held in the aperture 4 via an O-ring 20 in a cylinder 19 toward the inside wall side.