Extraction kinetics of six heavy metals from contaminated clay soils

Abstract The rate of the extraction of four heavy metals (Cu, Nl, Pb and Zn) from artificially polluted and waste site clay soils is determined in a 0.1 N HCl solution. A two‐reaction model is developed that describes the rate of extraction at a constant pH and at a constant temperature by two processes: a fast, irreversible reaction that is first‐order in the metal concentration in the clay and a slow, reversible first‐order reaction. The influence of the temperature on the extraction rate is measured over a range of 5 to 80°C for Ni extraction from an artificially polluted clay soil. Calculated values for the energy of activation suggest that the extraction process is rate‐limited by a diffusion process in the porous soil particles, but chemical limitations seem probable in case of the older contaminations in the waste site soils.

[1]  R. Griffin,et al.  Kinetic and Equilibrium Studies of Boron Desorption from Soil1 , 1974 .

[2]  J. J. Jurinak,et al.  Kinetics of the Phosphate Interaction with Calcite 1 , 1974 .

[3]  G. Soldatini,et al.  Pb adsorption by soils , 1976 .

[4]  B. E. Davies.  Soil Chemistry, Part A: Basic Elements: edited by G. H. Bolt and M. A. M. Bruggenwert, Elsevier, Amsterdam 1976, 281 pp., Price: $16.50 , 1977 .

[5]  Specific and non-specific sorption of cadmium by soil clays as influenced by zinc and calcium , 1979 .

[6]  ZINC ADSORPTION BY TWO ALKALINE SOLIDS , 1979 .

[7]  Adsorptieverschijnselen van zware metalen in gronden , 1980 .

[8]  L. M. Shuman,et al.  Selective Chemical Extraction of Soil Components and Bound Metal Species , 1981 .

[9]  R. Bowman,et al.  Soil Sorption of Nickel: Influence of Solution Composition 1 , 1981 .

[10]  J. Leckie,et al.  Trace-metal adsorption characteristics of estuarine particulate matter: evaluation of contributions of iron/manganese oxide and organic surface coatings , 1982 .

[11]  H. Häni,et al.  Dissolving Heavy Metals from Soils with Acids in order to Approximate Total Element Content , 1983 .

[12]  D. Sparks,et al.  Potassium‐Calcium Exchange in a Multireactive Soil System: I. Kinetics , 1984 .

[13]  R. Harter,et al.  Assessment of Copper-Soil Bond Strength by Desorption Kinetics1 , 1984 .

[14]  D. Sparks.  Soil Physical Chemistry , 1986 .

[15]  J. M. Martín,et al.  Sequential extraction techniques: Promises and problems , 1987 .

[16]  Extractive Cleaning of Heavy Metal Contaminated Clay Soils , 1987 .

[17]  S. Young,et al.  A constant potential titration method for studying the kinetics of Cu2+ desorption from soil and clay minerals , 1987 .

[18]  Extraction of heavy metals from contaminated clay soils , 1989 .

[19]  B. Tuin,et al.  Distribution of six heavy metals in contaminated clay soils before and after extractive cleaning. , 1990 .