Application of glassy carbon substrated cyanide‐sensitive electrodes in determination of cyanide and mercaptan levels of wastewater

Quantities of free and complex cyanides and mercaptans were determined in wastewater. Levels of free and complex cyanides were determined after previous oxidation of mercaptans by hydrogen peroxide. The procedure used for cyanide determination relied on applying a laboratory‐made glassy carbon (GC) substrated melt‐coated Agl “cyanide‐sensitive” electrode. The level of mercaptans was determined by iodometric titration in bicarbonate solution. Iodine was coulometrically generated using the depolarization end point detection on a GC/saturated calomel electrode indicating a couple connected directly to the recorder