Determination of Co and Ni in soils and river sediments by electrothermal atomic absorption spectrometry with slurry sampling

Cobalt and nickel were determined in slurry samples of soils and river sediments by electrothermal atomization atomic absorption spectrometry (ETAAS) with Zeeman effect background correction. It is suggested that cobalt and nickel can be determined simultaneously by slurry sampling ETAAS. The results of determinations with the use of slurry sampling technique and aqueous standards are in good agreement with certified values, and the repeatability of the over-all analytical procedure expressed as relative standard deviation is less than 8.8% for Ni and 6.9% for Co. The characteristic mass is 7.5 pg and 14.1 pg for Co and Ni, respectively. The analytical results are also compared with the results obtained by sample microwave assisted wet digestion followed by inductively coupled plasma – atomic emission spectrometry (ICP-AES) determination. The influence of sample grinding and sample homogeneity is discussed as well.