A non-optimised treatment of wastewaters containing organic and biological substances is very often accompanied by an accidental emanation of hydrogen sulphide H2S and therefore leads (i) to an undesirable odour in the vicinity of water treatment plants, and (ii) to a potential hazard for the neighbouring population. Fast, sensitive and reliable monitoring devices are hence of significant importance. Chalcogenide and chalcohalide glasses are new promising membrane materials for detection of heavy metal ions and toxic anions and particularly well adapted for continuous in situ monitoring and industrial process control. In the present paper, we will discuss analytical characteristics of new chalcogenide glass chemical sensors for detection of S2− and dissolved H2S, which allow reliable process control to be carried out at natural pH of wastewaters.
In-situ process control for semiconductor manufacturing