Development of a potentiometric flow cell with a stainless steel electrodefor pH measurements. Determination of acid mixtures using flow injection analysis

In this work a stainless steel electrode was prepared, characterised and us ed as indicator electrode in a potentiometric flow cell. Due to its versati lity, it was possible to study different electrode geometries and flow cell arrangements. After optimising the system, mixtures of succinic and oxalic acids were determined by titration. Partial least squares (PLS) regression as multivariate calibration tool was applied for data treatment. The predi cted results obtained in a test set showed a relative error of 4.3% for suc cinic acid and 5.5% for oxalic acid. (C) 2000 Elsevier Science B.V. All rig hts reserved.