FLOW-INJECTION DETERMINATION OF COMPOUNDS CONTAINING SULFUR BY USING POTENTIOMETRIC TUBULAR SENSOR

A flow-injection analysis (FIA) setup INTRODUCTION with flow-through t ubular solid-state AgI-based membrane detector, sensitive to the sulfh ydryl group, is examined. Application of a flow-injection system is ex emplified by the determination of different compounds containing sulfu r in 0.1 M HClO4 as a supporting electrolyte. For compounds with - SH group, a rectilinear calibration graph is obtained by plotting the pea k height versus concentration of RSH. The experimental slope is in goo d agreement with the theoretical (59 mV (p(RSH))(-1)) value postulated on an precipitation process and formation of RSAg into the carrier st ream or at the sensing part of the detector. The described FIA setup w ith utilized sensor can be applied for calculation of the solubility p roduct of RSAg or stability constant of Ag(SR)(n)((1-n)+) complex. (C) 1998 John Wiley & Sons, Inc. Lab Robotics and Automation 10: 143-149, 1998.