NOM-CD
Natural Organic Matter Charge Distribution — simulates metal binding to humic/fulvic acids using NICA-Donnan competitive adsorption on carboxylic and phenolic sites. Based on Hiemstra et al. 2013, Environ. Sci. Technol.
Model Parameters
Theoretical Basis
- NICA-Donnan: Non-Ideal Competitive Adsorption on two site types — carboxylic (high-affinity, low capacity) and phenolic (lower-affinity, higher capacity)
- Electrostatic correction: Donnan potential depends on pH and ionic strength, modulating apparent binding affinity
- Metal parameters: Calibrated against Milne et al. 2003 generic NICA-Donnan dataset (Geochim. Cosmochim. Acta)
Key References
- Hiemstra et al. (2013) Natural and pyrogenic natural organic matter (NOM) affect arsenate competition on goethite. Environ. Sci. Technol.
- Milne et al. (2003) Generic NICA-Donnan model parameters for proton and metal binding by humic substances. Geochim. Cosmochim. Acta.