Premium
Improved cadmium sorption isotherms by the determination of initial contents using the radioisotope 109 Cd
Author(s) -
Schug Bettina,
Düring RolfA.,
Gäth Stefan
Publication year - 2000
Publication title -
journal of plant nutrition and soil science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.644
H-Index - 87
eISSN - 1522-2624
pISSN - 1436-8730
DOI - 10.1002/(sici)1522-2624(200004)163:2<197::aid-jpln197>3.0.co;2-u
Subject(s) - cadmium , sorption , chemistry , environmental chemistry , freundlich equation , matrix (chemical analysis) , heavy metals , analytical chemistry (journal) , chromatography , nuclear chemistry , adsorption , organic chemistry
Cadmium (Cd) sorption isotherms were estimated by two different analytical approaches to assess the influence of initial Cd concentrations of soil matrix on the sorption of added Cd. For the laboratory experiments a heterogeneous set of samples was collected to include a wide range of different initial Cd concentrations. Comparison of both analytical methods (conventional analysis, radioanalysis) resulted in a strong conformity of Cd contents in solution at equilibrium. The calculated Cd concentrations in the soil solid phase differ according to the analytical approach for considering the initial contents. The determination of the initial contents by the proposed radioanalytical method with 109 Cd resulted in long linear Freundlich‐isotherms, even in the low concentration range. Thus, radioanalysis seems to be the most suitable method to recognise the initial contents of Cd in soil. EDTA extractable Cd represent the initial concentrations, which are averaged over solid and liquid phase. However, depending on the sorption characteristics of the soil these rates vary. In the investigated set of soil samples 52.3 to 99.3% of Cd must be added to the solid phase.