Flow-through coulometry as a calibrationless method in inorganic trace analysis

The possibility of calibration-less determination of trace concentrations o f some electrochemically active elements such as Ag, As, Cd, Hg, Pb, etc, b y flow-through coulometry is described. The analyte species are collected q uantitatively from the flowing sample solution on a porous working electrod e made of vitreous carbon particles set at either a constant potential orc The deposit is stripped by a constant current in the next step and the corr esponding electrical charge is measured and evaluated. The analyte concentr ation is calculated by making use of the combined Faraday's laws of electro lysis. The method exerts detection limits about 1 mug/l or lower and a line ar concentration range over 3 orders of magnitude.