Acid/base, copper binding, and Cu{sup 2+}/H{sup +} exchange properties of a soil humic acid, an experimental and modeling study
- Stanford Univ., CA (United States)
Acid/base, copper binding and proton exchange properties of a soil humic acid were studied over a range of pHs and ionic strengths. Results indicate that multiple classes of copper binding sites exist. A number of model formulations were used to simulate the data; none were able to reasonably match all aspects of the observed behavior. Model results and analyses suggest that successful replication of humic behavior over a wide range of conditions requires a model formulation which incorporates electrostatic effects for a variable geometry entity, multiple site classes, and probably both uni and multi dentate complexation. Additionally site heterogeneity estimates from acid/base titration data are not likely to reasonably assess the presence of low concentration, high (metal) affinity sites that can be relevant in the study of trace metal complexation.
- OSTI ID:
- 335329
- Journal Information:
- Environmental Science and Technology, Journal Name: Environmental Science and Technology Journal Issue: 5 Vol. 33; ISSN ESTHAG; ISSN 0013-936X
- Country of Publication:
- United States
- Language:
- English
Similar Records
Application of a continuous distribution model for proton binding by humic acids extracted from acidic lake sediments
Acid/base, copper binding, and Cu{sup 2+}/H{sup +} exchange properties of goethite, an experimental and modeling study