Electrochemical detection of sulphide: a novel dual flow cell

A novel application of a dual flow electrochemical cell to the detection of hydrogen sulphide is presented. The sensor employs the electrochemically initiated reaction of N, N-dimethylphenylene-1,4-diamine (DMPD) with sulphide as the main analytical signal. The redox indicator is passed through one channel while sulphide effluent is flowed through the other with the streams separated by the use of a gas-permeable membrane. Preliminary results have shown that the sensor responds linearly to sulphide over the range 20-103 mu M with the signal profile and response time capable of modulation through variation in the flow rates of the two streams. (C) 2000 Elsevier Science S.A. All rights reserved.