Determination of chromium by electrothermal atomisation atomic absorption spectrometry
The graphite furnace AAS technique, using both pyrocoated graphite and tantalum carbide coated tubes, has been used for the determination of chromium in steel. Both tubes were found to be superior for the elimination of the interference caused by iron. A 5-fold higher sensitivity of the determination of chromium was obtained with the tantalum carbide coated tube than with the pyrocoated tube. In addition, the lifetime of the tantalum carbide coated tube was found to be about twice that of the pyrocoated tube.