title: On-line titration of non-ionic surfactants in wastewater treatment plants using a specific electrode.
abstract: Textile finishing industry wastewater often contains high concentrations of surfactants. Non-ionic surfactants like alcohol ethoxylates are among the most used surfactants and are discharged from batch-processes in widely varying concentrations. The anaerobic biomass and especially methanogenic microorganisms have been shown to be inhibited by surfactants. To protect these microorganisms from irreversible inhibition a measurement of the surfactant concentration is useful for the process control, but most analytical methods are too complicated and expensive for an on-line process control. It was shown that the titration of non-ionic surfactants is possible in the presence of biomass and in wastewater from textile wet processes using the Metrohm NIO-electrode. Titration and sampling were successfully performed with standard equipment. The software used for the process control of a lab-scale anaerobic treatment plant was also used to evaluate the obtained titration curves. This allowed performing the titrations without using a more expensive titrator.
authors.affiliation: Laboratorium für Technische Chemie, ETH Zürich, HCI, Switzerland.
authors.forename: H
authors.initials: H
authors.lastname: Feitkenhauer
authors.forename: U
authors.initials: U
authors.lastname: Meyer
mesh_terms: D000438:Alcohols / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D001421:Bacteria, Anaerobic / Q000378:metabolism; D018533:Biomass; D019149:Bioreactors; D004566:Electrodes; D012984:Software; D013501:Surface-Active Agents / Q000737:chemistry* / Q000302:isolation & purification* / Q000378:metabolism; D013783:Textile Industry; D013997:Time Factors; D017186:Titrimetry / Q000379:methods*; D014871:Water Microbiology; D018508:Water Purification / Q000295:instrumentation* / Q000379:methods*
chemical_list: D000438:Alcohols; D013501:Surface-Active Agents; C061143:Neodol-12