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arXiv · 2303.08761

Diffusiophoresis and medium structure control macroscopic particle transport in porous media

Mamta Jotkar·Pietro de Anna·Marco Dentz·Luis Cueto-Felgueroso
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Abstract

In this letter, we show that pore-scale diffusiophoresis of colloidal particles along local salt gradients manifests in the macroscopic dispersion of particles in a porous medium. Despite is transient character, this microscopic phenomenon controls large-scale particle transport by altering their partitioning between transmitting and dead-end pores. It determines the distribution of residence and arrival times in the medium. Depending on the diffusiophoretic mobility, particles can be mobilized from or trapped in dead-end pores, which provides a means for the controlled manipulation of particles in porous media.

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Mamta Jotkar, Pietro de Anna, Marco Dentz, Luis Cueto-Felgueroso. 2023-03-15. Diffusiophoresis and medium structure control macroscopic particle transport in porous media. https://arxiv.org/abs/2303.08761

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