Continuous flow analysis: Photometric determination of Cr(III) with ChromeAzurol S using microwave treatment

The effect of microwave and ultraviolet radiation and ultrasonic treatment on the reaction of chromium(III) with Chrome Azurol S, Arsenate I, Alizarin , and Thoron was studied in the batch and flow modes. It was found that the reaction of chromium with the above photometric reagents is most efficient ly activated by microwave radiation of the power 500-200 Wt. The best analy tical properties were found for Chrome Azurol S. A flow system was proposed for the photometric determination of chromium(III) with Chrome Azurol S us ing microwave treatment. The throughput of the system is 68 samples per hou r, the analytical range for chromium(III) is 0.03-60 mg/L. Na, K, Mg, Ca, Z n, Cd, Pb, Cl-, SO42-, NO3-, CH3COO- in 1000-fold amounts; Cu(II) and F- in 500-fold amounts; Fe(III) in a 10-fold amount; and Cr(VI) in a sevenfold a mount do not interfere with the determination of Cr(III). Procedures for th e photometric determination of chromium under batch conditions were develop ed. The accuracy of the developed procedures was verified in the analysis o f tanning agents and dyes for leather.