Premium
Ion Chromatographic Determination of Total Metals in Soils
Author(s) -
Basta N. T.,
Tabatabai M. A.
Publication year - 1990
Publication title -
soil science society of america journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.836
H-Index - 168
eISSN - 1435-0661
pISSN - 0361-5995
DOI - 10.2136/sssaj1990.03615995005400050015x
Subject(s) - chemistry , dithizone , absorbance , atomic absorption spectroscopy , metal ions in aqueous solution , column chromatography , metal , oxalic acid , resorcinol , extraction (chemistry) , ion chromatography , spectrophotometry , chromatography , analytical chemistry (journal) , inorganic chemistry , physics , organic chemistry , quantum mechanics
An accurate and precise ion chromatographic (IC) method for determination of total Cu, Ni, and Zn in soils was developed. The sample preparation method consists of three steps: (i) digestion of the soil sample by using HNO 3 , HClO 4 , and HF; (ii) extraction of the metals of interest by using dithizone in CHCl 3 ; and (iii) destruction of the metal‐dithizonate complex with HNO 3 . The system consisted of a guard (HPIC‐CG5) column and a separator (HPIC‐CS5) column followed by postcolumn reaction with 4‐(2‐pyridylazo) resorcinol ( par ), to form colored metal complexes. The absorbance of the metal‐ par complexes was measured by an ultraviolet‐visible light ( uv‐vis ) detector at 520 nm. Two different eluents were required for separation of these and other metals. Simultaneous determination of Cd, Cu, Mn, and Zn was achieved by using an eluent containing 4 m M 2,6‐pyridinedicarboxylic acid ( pdca ) and 50 m M HOAc‐NaOAc buffer (pH 4.8). Simultaneous determination of Cu, Ni, Pb, and Zn was accomplished by using an eluent containing 40 m M oxalic acid and 50 m M HOAc‐LiOAc buffer (pH 4.8). Results by the IC method for determination of total Cu, Ni, and Zn in 14 soils were in good agreement with those obtained by atomic absorption spectrophotometry, but results also showed that the proposed IC method is inadequate for determination of total Cd, Mn, and Pb in soils.