Related Experiment Video
Updated: Jun 7, 2025
10:52
Multiscale Sampling of a Heterogeneous Water/Metal Catalyst Interface using Density Functional Theory and Force-Field Molecular Dynamics
Published on: April 12, 2019
12.7K
Mechanistic Modeling of Pollutant Mass Redistribution (Sorption/Desorption) in Heterogeneous Systems Explaining
Binlong Liu1, Michael Finkel1, Qiyue Qin1
1Department of Geosciences, University of Tübingen, Schnarrenbergstraße 94-96, Tübingen 72076, Germany.
Environmental Science & Technology
|November 20, 2024
Summary
This study introduces a new model for pollutant transfer in heterogeneous systems, explaining complex kinetics and overshooting concentrations. The model aids in understanding contaminant behavior in soils and water bodies.
Area of Science:
- Environmental Science
- Environmental Chemistry
- Chemical Engineering
Background:
- Pollutant redistribution between solid phases is common in natural and lab settings.
- Modeling sorption/desorption kinetics is complex due to multiple mass transfer mechanisms and particle heterogeneity.
Purpose of the Study:
- To develop a semi-analytical model for simulating pollutant redistribution kinetics in heterogeneous systems.
- To account for coupled intraparticle and external boundary layer diffusion.
- To consider sorbent heterogeneity (shape, size, capacity, solid/porous nature).
Main Methods:
- Formulation of a semi-analytical model in the Laplace domain.
- Validation against batch experiments involving phenanthrene, anthracene-d10, and polyethylene particles/sediment suspensions.
Main Results:
- The model successfully explains temporary overshooting of aqueous phase concentrations.
- It accounts for varying kinetic controls (fast desorption vs. slow sorption) from different particles.
- The model clarifies initial fast kinetics followed by long tailing observed in experiments.
Conclusions:
- The developed model provides a flexible approach to simulate pollutant redistribution in complex environmental systems.
- It enhances understanding of contaminant dynamics influenced by heterogeneous sorbents and coupled mass transfer processes.
- The model is applicable to diverse scenarios involving pollutant transfer between solid and aqueous phases.
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