Impurity mediated nucleation in hexadecane-in-water emulsions

TL;DR

This study investigates the nucleation process of hexadecane in water emulsions, revealing deviations from classical theory due to impurity-induced droplet heterogeneity, and proposes a new explanation involving mobile impurities.

Contribution

It introduces a novel impurity-mediated mechanism explaining nucleation heterogeneity in emulsions, challenging classical homogeneous assumptions.

Findings

Deviations from classical nucleation theory observed

Impurities induce droplet heterogeneity affecting nucleation

Proposed model aligns well with experimental data

Abstract

We report detailed nucleation studies on the liquid-to-solid transition of hexadecane using nearly monodisperse hexadecane-in-water emulsions. A careful consideration of the kinetics of isothermal and nonisothermal freezing show deviations from predictions of classical nucleation theory, if one assumes that the emulsion droplet population is homogeneous. Similar deviations have been observed previously. As an explanation, we propose a novel argument based on the dynamic generation of droplet heterogeneity mediated by mobile impurities. This proposal is in excellent agreement with existing data.