We found a match
Your institution may have rights to this item. Sign in to continue.
- Title
EFFECTS OF pH, CHLORIDE AND CALCIUM(II) ON ADSORPTION OF MONOMETHYLMERCURY BY SOILS.
- Authors
Yin, Yujun; Allen, Herbert E.; Huang, C.-P.; Sanders, Paul F.
- Abstract
Adsorption of monomethylmercury (MMHg) by soil from 2 x 107 and 1 x 10-6 M solutions was investigated to understand soil-water partitioning of MMHg. The effects of three factors -- pH, Cl-, and Ca1+ -- on adsorption were examined. Adsorption as a function of pH followed a concave downward profile with the maximum adsorption occurring at pH between 5 and 6. Less adsorption at low pH values mainly resulted from the proton competition for surface sites and Cl- complexation for MMHg. Decreases in adsorption at high pH values are attributed to the complexation of MMHg with soluble organic ligands whose concentrations increase with pH. Addition of 1.0 x 10-3 M Cl- decreased adsorption at low pH where CH3 HgCl was dominant over CH3 HgOH, and exhibited no effect on adsorption at high pH when CH3 HgOH became predominant. The presence of a low concentration of Ca2+ (1.0 x 10-4 M) had no effect on MMHg adsorption; however, a high concentration of Ca2+ (3.3 x 10-3 M) increased adsorption at pH < 6 but had no effect at pH > 6. This is ascribed to the combined effects of pH and Ca2+ on the solubility of organic ligands.
- Subjects
MERCURY compounds; SOILS; WATER; CHLORINE; CALCIUM; ADSORPTION (Chemistry); LIGANDS (Chemistry)
- Publication
Environmental Toxicology & Chemistry, 1997, Vol 16, Issue 12, p2457
- ISSN
0730-7268
- Publication type
Article
- DOI
10.1002/etc.5620161204