A Sensor-Controlled Flow Apparatus for Fast Online Titrations

A process‐suitable titration apparatus was developed for fast online titrations. It consists of computer‐controlled gradient pumps, a sample dilution setup, mixing devices and a microfabricated flow cell with potentiometric sensor. The flow control of the pumps is done via the electrode response signal and a control program applying the feedback algorithm. The apparatus allows the conduction of titration experiments in time cycles of 30 – 50 s in a continuously flowing sample stream. It is about ten times faster than classical batch titrations while accuracy and precision remain of similar magnitude. The long‐term stability and the applicability to process control are shown in field tests. The presented increase of speed, decrease of size and explosion proof make titrations suitable as online technique in the process industry.