Bitumen Emulsion Destabilization Kinetics : Importance of the Crystallized Wax Content
We study the kinetics of bitumen emulsion destabilization after the addition of sodium hydroxide (NaOH) using macroscopic observations and rheology. Destabilization occurs in a two-step process: first, emulsion flocculates, forming a percolated network of contacting drops, and then coalescence provo...
| Veröffentlicht in: | Langmuir : the ACS journal of surfaces and colloids. - 1992. - 33(2017), 38 vom: 26. Sept., Seite 9740-9749 |
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| Weitere Verfasser: | , , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2017
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| Zugriff auf das übergeordnete Werk: | Langmuir : the ACS journal of surfaces and colloids |
| Schlagworte: | Journal Article Research Support, U.S. Gov't, Non-P.H.S. |
| Zusammenfassung: | We study the kinetics of bitumen emulsion destabilization after the addition of sodium hydroxide (NaOH) using macroscopic observations and rheology. Destabilization occurs in a two-step process: first, emulsion flocculates, forming a percolated network of contacting drops, and then coalescence provokes the irreversible connection of bitumen drops, leading to a bitumen continuous network that further relaxes the shape. We show that the destabilization kinetics exhibits a rheological easily identifiable signature allowing reproducible and accurate measurement of the connection/coalescence time trc (which corresponds to the time, determined by rheology, required to form the network made of drops connected by nonrelaxed coalescence). Using this powerful tool, we show that, even if viscosity is thought to govern the shape relaxation of the connected network it does not determine the connection kinetics. Indeed, emulsions with similar rheological behaviors exhibit very different destabilization times. Instead, we evidence a good correlation between the bitumen crystallized wax content and trc. From these experimental results, we discuss the stabilizing effect against coalescence of crystals in bitumen emulsions |
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| Beschreibung: | Date Completed 23.07.2018 Date Revised 23.07.2018 published: Print-Electronic Citation Status PubMed-not-MEDLINE |
| ISSN: | 1520-5827 |
| DOI: | 10.1021/acs.langmuir.7b01578 |