Mobilization of colloidal ferrihydrite particles in porous media—An inner-sphere complexation approach

Statistics – Applications

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

Prediction of colloid release and transport as affected by reactive species remains a significant challenge for field applications. In this paper, we report experimental and modeling results of ferrihydrite colloid release under the influence of citrate species. Using a 3-plane surface complexation model, equilibrium constants were obtained for the three proposed inner-sphere complexes by fitting a citrate adsorption isotherm on ferrihydrite at pH 4, and a pH adsorption envelop with 0.64 mM citrate. The constants were used in a reactive transport model for simulating reaction fronts of dissolved species during injection of citrate in ferrihydrite-coated quartz columns. Simulation results show that sorption alone may not adequately describe the breakthrough curves. Inclusions of ferrihydrite dissolution and re-adsorption of Fe(III) improve the prediction of dissolved species transport. Additionally, matrix diffusion may be needed for improved prediction. For the release of colloidal iron oxides it was shown that both oxide dissolution and interfacial repulsion controlled the process during complete breakthrough. However, the peak release of colloids, which occurred during the actual breakthrough of dissolved species, was mainly brought about by electric double layer forces. These particles underwent detachment deposition detachment cycles along the flow path, and emerged in the effluent with the major reaction front. To quantitatively predict colloid release, a semi-empirical linear correlation was established, linking the calculated electric potential to experimental colloid release rates. The model may be applied to the prediction and scaling of aquifer remediation studies involved in the injection of organic ligands to mobilize particle bound contaminants.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Mobilization of colloidal ferrihydrite particles in porous media—An inner-sphere complexation approach does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Mobilization of colloidal ferrihydrite particles in porous media—An inner-sphere complexation approach, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Mobilization of colloidal ferrihydrite particles in porous media—An inner-sphere complexation approach will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1757439

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.