Solubility enhancement of seven metal contaminants using carboxymethyl-beta-cyclodextrin (CMCD)

J Contam Hydrol. 2009 Jul 21;107(3-4):108-13. doi: 10.1016/j.jconhyd.2009.04.006. Epub 2009 Apr 20.

Abstract

Carboxymethyl-beta-cyclodextrin (CMCD) has been suggested as a complexing agent for remediation of sites co-contaminated with metals and organic pollutants. As part of an attempt to construct a geochemical complexation model for metal-CMCD interactions, conditional formation constants for the complexes between CMCD and 7 metal ions (Ba, Ca, Cd, Ni, Pb, Sr, and Zn) are estimated from experimental data. Stable metal concentrations were reached after approximately 1 day and estimated logarithmic conditional formation constants range from -3.2 to -5.1 with confidence intervals within +/-0.08 log units. Experiments performed at 10 degrees C and 25 degrees C show that temperature affects the solubility of the metal salts but the strength of CMCD-metal complexes are not affected by this temperature variation. The conditional stability constants and complexation model presented in this work can be used to screen CMCD as a potential remediation agent for clean-up of contaminated soil and groundwater.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Environmental Pollution / prevention & control*
  • Metals / chemistry*
  • Solubility
  • Surface-Active Agents
  • beta-Cyclodextrins / chemistry*

Substances

  • Metals
  • Surface-Active Agents
  • beta-Cyclodextrins
  • carboxymethyl-beta-cyclodextrin