Abstract
Intraparticle surface diffusion is an important and rate-limiting process in the sorption of metal ions to microporous sorbents such as those of hydrous amorphous Al (HAO), Fe (HFO), and Mn (HMO) oxides; these minerals are abundant in the environment, exhibiting a high affinity for metal contaminants. In aquatic systems representative of natural environments, internal micropore surfaces of HAO, HFO, and HMO can account for 40 to 90% of the sorption sites. Surface diffusivities have been observed to range between 10-16 and 10-10 cm2 s-1 for metals including Sr, Cd, Zn, and Ni. The combination of significant microporosity and small diffusivities results in the amorphous oxides acting as natural attenuating sinks.
Original language | English (US) |
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Pages (from-to) | 259-265 |
Number of pages | 7 |
Journal | Journal of Colloid And Interface Science |
Volume | 247 |
Issue number | 2 |
DOIs | |
State | Published - 2002 |
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Surfaces, Coatings and Films
- Biomaterials
- Colloid and Surface Chemistry
Keywords
- And adsorption enthalpy
- Hydrous aluminum oxide
- Hydrous iron oxide
- Hydrous manganese oxide
- Intraparticle surface diffusion
- Metal ion adsorption
- Sorption