Abstract
After the microwave acid digestion of a solid sample of 100mg in a sealed double PTFE vessel with a polypropylene jacket and the extraction removal of iron with Hinokitiol into benzene, copper, cobalt and nickel were extracted with ammonium pyrrolidinedithiocarbamate into chloroform. Direct injection of the chloroform extract into a flame gave an characteristic signal profile for Cu, Co and Ni. Injection volumes of 35-45μl of the chloroform extract gave the highest, most constant and most reproducible signals. When we nebulized 40μl of the chloroform extract, three metals were well determined by one-drop flame atomic absorption spectrometry with deuterium background correction. The method was successfully applied to the determination of three elements in a certified reference material (NIES-CRM No. 1, Pepperbush) from the National Institute for Environmental Studies; the result agreed well with the certified values.
