A method determining di-and tri-valent cobalt extracted from soils with EDTA·HOAc·NH4OAc solution (pH4.65) was developed based on the difference of the stability constants of Co(II) EDTA and Co(III) EDTA.Ana...A method determining di-and tri-valent cobalt extracted from soils with EDTA·HOAc·NH4OAc solution (pH4.65) was developed based on the difference of the stability constants of Co(II) EDTA and Co(III) EDTA.Analytical results indicated that soil cobalt existed in both two oxidation states,i.e.,di-and tri-valent cobalt.Extractable di-valent cobalt in 60 soil samples collected from various soils in China ranged from 0.02 ppm to 3.54ppm,with the mean of 0.62ppm,and extractable tri-valent cobalt from 0.04 ppm to 27.65ppm,with the mean of 2.93ppm.展开更多
文摘A method determining di-and tri-valent cobalt extracted from soils with EDTA·HOAc·NH4OAc solution (pH4.65) was developed based on the difference of the stability constants of Co(II) EDTA and Co(III) EDTA.Analytical results indicated that soil cobalt existed in both two oxidation states,i.e.,di-and tri-valent cobalt.Extractable di-valent cobalt in 60 soil samples collected from various soils in China ranged from 0.02 ppm to 3.54ppm,with the mean of 0.62ppm,and extractable tri-valent cobalt from 0.04 ppm to 27.65ppm,with the mean of 2.93ppm.
