Study of the emulsion droplet collisions with the polarizable water/1,2-dichloroethane interface by the open circuit potential measurements

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388955%3A_____%2F19%3A00500333" target="_blank" >RIV/61388955:_____/19:00500333 - isvavai.cz</a>

Result on the web

<a href="http://hdl.handle.net/11104/0292425" target="_blank" >http://hdl.handle.net/11104/0292425</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.electacta.2019.01.041" target="_blank" >10.1016/j.electacta.2019.01.041</a>

Result language

angličtina

Original language name

Study of the emulsion droplet collisions with the polarizable water/1,2-dichloroethane interface by the open circuit potential measurements

Original language description

The open circuit potential (OCP) measurements are used to study the single collisions of the DCE-in-water emulsion droplets containing an electrolyte (tetradodecylammonium chloride, TDDACl) with the polarizable water/1,2-dichloroethane (DCE) interface. The OCP transients exhibit a series of the potential spikes, which consist of the initial negative potential step followed by a slower relaxation of the potential to its original value. A novel mechanism of the collisions is proposed including the interpretation of the potential response shape. Low stability of the emulsion system precluded a convincing comparison of the OCP and DLS data, though in some cases the size distributions obtained by OCP and DLS measurements may coincide. A comparison of the interfacial tension or capacitance curves measured in the absence and presence of the emulsion droplets indicates that their specific adsorption at the water/DCE interface is negligible. The mean droplet diameter exhibits a monotonic increase with the increasing droplet concentration and time pointing to an increasing effect of the flocculation and coalescence. The change of the collision frequency with the emulsion droplet concentration can be rationalized by using a steady-state diffusion transport model, which predicts that the collision frequency scales down with the fourth power of the droplet diameter. The droplet size distribution is not much affected by a change in the TDDACl concentration, which leads to the proportional change of the total charge integrated from all the emulsion droplet collisions. However, the total charge itself represents only a small fraction of the charge theoretically available, which suggests that a large portion of the collisions are accompanied by the zero-net charge transfer of the neutral ion pair TDDA+Cl−, and/or a number of the droplets are lost through their accumulation on the glass walls of the experimental system. The DCE-in-water emulsion exhibits a very low stability, which is manifested primarily by a strong effect of the droplet concentration on the mean droplet diameter or by its increase with time, as well as by a difference in the droplet size distributions averaged over different time spans. Breakdown of this emulsion system seems to occur through a combination of the flocculation, coalescence and sedimentation. Nevertheless, the OCP measurements provide a valuable insight into its interfacial dynamic behavior.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10405 - Electrochemistry (dry cells, batteries, fuel cells, corrosion metals, electrolysis)

Project

<a href="/en/project/GA17-09980S" target="_blank" >GA17-09980S: Biomimetic electrochemistry of emulsion micro-droplets at the polarised interface between two immiscible electrolyte solutions</a><br>

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2019

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Electrochimica acta

ISSN

0013-4686

e-ISSN

—

Volume of the periodical

299

Issue of the periodical within the volume

MAR 2019

Country of publishing house

GB - UNITED KINGDOM

Number of pages

11

Pages from-to

875-885

UT code for WoS article

000457551900094

EID of the result in the Scopus database

2-s2.0-85060917002