DETERMINATION OF CHROMIUM, COBALT, AND IRON BY FLAME ATOMIC-ABSORPTION SPECTROPHOTOMETRY USING VOLATILIZATION OF METAL TRIFLUOROACETYL ACETONATES

A sample-introduction method for flame-atomic absorption spectrophotometry is described. Solutions of trifluoroacetyl acetonate complexes of chromium, cobalt, and iron are volatilized, and then atomized in a heated silica tube connected directly to the generation apparatus. The complex vapor is carried to the atomizer by nitrogen. The combination of volatilization and silica tube atomization increases sensitivity by factors of 60, 25, and 4 for chromium, cobalt, and iron, respectively (compared with flame atomization of the metal solution), with a relative standard deviation of the order of 5%. © 1990.