Competitive complexation of trace metals to dissolved humic acid
| dc.contributor.advisor | Conklin, Martha H. | en |
| dc.contributor.author | Cao, Yi | |
| dc.creator | Cao, Yi | en |
| dc.date.accessioned | 2018-02-28T19:44:12Z | |
| dc.date.available | 2018-02-28T19:44:12Z | |
| dc.date.issued | 1993 | |
| dc.identifier.uri | http://hdl.handle.net/10150/626920 | |
| dc.description.abstract | Effects of competing trace metals (10 µM) and Ca 2+ (5 mM) on Cd(II), Pb(II) and Cu(II) (0 - 100 µM) complexation by a groundwater humic acid were investigated in a series of 24 batch experiments at pH 6, 7, and 8 (I = 0.05 M). Both trace metals and Ca 2+ have little effect on Cd(II) complexation. No effect of Cu(II) on Pb(II) complexation is observed; Cd(II) appears to slightly enhance the binding between Pb(II) and humic acid. For Cu(II), the addition of Pb(II) decreases the amount of complexation, but Cd(II) also appears to slightly increase it. Calcium, however, decreases the amount of complexation in all cases. The effective binding constants determined show that the relative magnitudes of binding strengths are Cu(II) ,.., Pb(II) > Cd(II). These results indicate that in groundwaters, where more than one metal is present, the effect of other metals must be considered when predicting metal speciation. | |
| dc.language.iso | en_US | en |
| dc.publisher | The University of Arizona. | en |
| dc.rights | Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. | en |
| dc.title | Competitive complexation of trace metals to dissolved humic acid | en_US |
| dc.type | text | en |
| dc.type | Thesis-Reproduction (electronic) | en |
| thesis.degree.grantor | University of Arizona | en |
| thesis.degree.level | masters | en |
| dc.contributor.committeemember | Conklin, Martha H. | en |
| dc.contributor.committeemember | Betterton, Eric | en |
| thesis.degree.discipline | Graduate College | en |
| thesis.degree.discipline | Hydrology and Water Resources | en |
| thesis.degree.name | M.S. | en |
| dc.description.note | Digitized from paper copies provided by the Department of Hydrology & Atmospheric Sciences. | en |
| refterms.dateFOA | 2018-06-24T13:16:27Z | |
| html.description.abstract | Effects of competing trace metals (10 µM) and Ca 2+ (5 mM) on Cd(II), Pb(II) and Cu(II) (0 - 100 µM) complexation by a groundwater humic acid were investigated in a series of 24 batch experiments at pH 6, 7, and 8 (I = 0.05 M). Both trace metals and Ca 2+ have little effect on Cd(II) complexation. No effect of Cu(II) on Pb(II) complexation is observed; Cd(II) appears to slightly enhance the binding between Pb(II) and humic acid. For Cu(II), the addition of Pb(II) decreases the amount of complexation, but Cd(II) also appears to slightly increase it. Calcium, however, decreases the amount of complexation in all cases. The effective binding constants determined show that the relative magnitudes of binding strengths are Cu(II) ,.., Pb(II) > Cd(II). These results indicate that in groundwaters, where more than one metal is present, the effect of other metals must be considered when predicting metal speciation. |
