caa a22 4500 37892740X CHVBK 20180305123621.0 cr unu---uuuuu 161128e20041101xx s 000 0 eng 10.1524/ract.92.9.567.54984 doi (NATIONALLICENCE)gruyter-10.1524/ract.92.9.567.54984 Application of the NICA-Donnan model for proton, copper and uranyl binding to humic acid [Elektronische Daten] [Takumi Saito, S. Nagasaki, S. Tanaka, L. K. Koopal] Humic acids are natural organic materials that play an important role in the migration of heavy metal and actinide ions in aquatic and soil systems. In the present study, the binding of protons, copper ions and uranyl ions to the purified Aldrich humic acid (PAHA) is investigated and the results are modeled with the Non-Ideal Competitive Adsorption (NICA) model extended with electrostatic interactions according to the Donnan model (NICA-Donnan model). The NICA part of the model enables one to describe the competitive ion binding to a heterogeneous substrate taking into account a different stoichiometry per ion. The NICA-Donnan model can describe the binding of the ions to PAHA in large concentration ranges (3<pH<11; 3<pCu<13; 4<pUO2<18) and over a wide range of environmental conditions (pH, ionic strength). From the model description it follows that the affinity distribution of PAHA is bimodal with about equal numbers of "carboxylic"- (low logKH) and "phenolic"-type (high log KH) sites. The stoichiometry parameters of the binding reactions for copper and uranyl indicate both mono- and bi-dentate binding. Some specific attention is paid to the distribution of the bound uranyl ions over the "carboxylic" and "phenolic"-type sites. Such information is useful for comparison with spectroscopic information on the binding. © 2004 Oldenbourg Wissenschaftsverlag GmbH Laboratory techniques, experiments nationallicence Analytical chemistry nationallicence Inorganic chemistry nationallicence Saito Takumi aut Nagasaki S. aut Tanaka S. aut Koopal L. K. aut Radiochimica Acta/International journal for chemical aspects of nuclear science and technology Oldenbourg Wissenschaftsverlag GmbH 92/9-11/2004(2004-11-01), 567-574 0033-8230 92:9-11/2004<567 2004 92 ract https://doi.org/10.1524/ract.92.9.567.54984 text/html Onlinezugriff via DOI 1 research article jats NATIONALLICENCE 856 40 https://doi.org/10.1524/ract.92.9.567.54984 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Saito Takumi aut NATIONALLICENCE 700 1- Nagasaki S. aut NATIONALLICENCE 700 1- Tanaka S. aut NATIONALLICENCE 700 1- Koopal L. K. aut NATIONALLICENCE 773 0- Radiochimica Acta/International journal for chemical aspects of nuclear science and technology Oldenbourg Wissenschaftsverlag GmbH 92/9-11/2004(2004-11-01), 567-574 0033-8230 92:9-11/2004<567 2004 92 ract CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-gruyter