DETERMINATION OF CYANIDE BY A FLOW-INJECTION ANALYSIS-ATOMIC ABSORPTION SPECTROMETRIC METHOD

A new flow injection analysis (FIA) procedure is proposed for the indi rect atomic absorption spectrometric determination of cyanide. The FIA manifold is based on the insertion of the sample into a distilled wat er carrier, then the sample flows through a solid-phase reactor filled with silver iodide entrapped in polymeric resin beads. The calibratio n graph is linear over the range 0.2-6.0 mg l(-1) of cyanide (correlat ion coefficient 0.9974), the detection limit is 0.1 mg l(-1), the samp le throughput is 193 h(-1) and the RSD is 0.8%. The method is simple, quick and more selective than other published FIA procedures. The repr oducibility obtained by using different solid-phase reactors and solut ions is in the range 2.2-3.1% (RSD). The method was applied to the det ermination of cyanide in commercial samples such as pharmaceutical for mulations and industrial electrolytic baths.