Startseite Thermodynamics of Micellization, Interfacial Behavior and Wettability Alteration of Aqueous Solution of Nonionic Surfactants
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Thermodynamics of Micellization, Interfacial Behavior and Wettability Alteration of Aqueous Solution of Nonionic Surfactants

  • Sunil Kumar und Ajay Mandal
Veröffentlicht/Copyright: 6. September 2017
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Tenside Surfactants Detergents
Aus der Zeitschrift Tenside Surfactants Detergents Band 54 Heft 5

Abstract

The present work deals with the physiochemical properties of polyoxyethylene sorbitan fatty acid esters (polysorbates), which are commonly known under the trade name Tween. Thermodynamics of micellization and adsorption at air-water interface for these nonionic surfactants solutions have been studied over a broad range of temperature. As the temperature of the surfactant solutions increases, the surface tension decreases whereas the critical micelle concentration (CMC) of each surfactant solution initially decreases and then increases. The free Gibb free energies of the micelle formation ΔGmo, and the surfactant adsorptionΔGadso, are calculated for the CMC of each surfactant at different temperatures. The surface or expanding pressure (Πcmc), minimum area per molecule (Amin), maximum surface excess (Γmax) are also calculated. The interfacial tension (IFT) between the aqueous surfactant solutions and the crude oil are measured at different concentrations of the surfactants using a spinning drop tensiometer. The contact angles are determined on an oil wet quartz surface to investigate the wettability alteration in the presence of Tween surfactants with varying salinity. FTIR analysis of quartz at dry and oil wet state, crude oil and COBRS (crude oil-brine-rock-surfactant) combinations are performed to identify the associated functional groups and their mutual interactions.

Kurzfassung

Die vorliegende Arbeit beschäftigt sich mit den physiochemischen Eigenschaften von Polyoxyethylensorbitanfettsäureestern (Polysorbate), die unter dem Handelsnamen Tween bekannt sind. Die Thermodynamik der Mizellenbildung und der Adsorption an der Luft-Wasser-Grenzfläche für diese nichtionischen Tensidlösungen wurde über einen breiten Temperaturbereich untersucht. Wenn die Temperatur der Tensidlösungen zunimmt, nimmt die Oberflächenspannung ab, während die kritische Mizellenbildungskonzentration (CMC) jeder Tensidlösung anfänglich abnimmt und dann zunimmt. Die freie Gibb-Energie der Mizellenbildung ΔGmo und die der Tensidadsorption ΔGadso werden für jedes Tensid bei der CMC für verschiedene Temperaturen berechnet. Es werden auch der Oberflächen- oder Expansionsdruck (Πcmc), der minimale Platzbedarf pro Tensidmolekül (Amin) und der maximale Oberflächenüberschuss (Γmax) berechnet. Die Grenzflächenspannung (IFT) zwischen den wässrigen Tensidlösungen und dem Rohöl werden bei verschiedenen Tensidkonzentrationen mit einem Spinning-Drop-Tensiometer gemessen. Die Kontaktwinkel werden auf einer mit Öl benetzten Quarzoberfläche bestimmt, um die Änderung der Benetzung in Gegenwart von Tween-Tensiden mit unterschiedlichem Salzgehalt zu ermitteln. Die FT-IR-Analyse von Quarz im Trocken- und im mit Öl benetzten Zustand, des Rohöls und der COBRS-Kombinationen (Rohöl-Sole-Rock-Tensid) werden durchgeführt, um die zugehörigen funktionellen Gruppen und ihre gegenseitigen Wechselwirkungen zu identifizieren.

Key words: Micellization; nonionic surfactant; critical micelle concentration (CMC); interfacial tension (IFT); contact angle
Stichwörter: Mizellenbildung; nichtionisches Tensid; kritische Mizellenbildungskonzentration (CMC); Grenzflächenspannung (ITF); Kontaktwinkel
*Correspondence address, Dr. Ajay Mandal, Department of Petroleum Engineering, Indian Institute of Technology (ISM), Dhanbad 826004, India, E-Mail:

Dr. Ajay Mandal is presently working as Associate Professor in Department of Petroleum Engineering, Indian Institute of Technology (ISM), Dhanbad. His research area includes, synthesis and characterization of surfactants, enhanced oil recovery, gas hydrates and multi-phase flow system. He has published more than 100 research papers in reputed peer reviewed International and National Journals. He is a reviewer of many International Journals. Dr. Mandal has been awarded 2015 SPE South Asia Regional Distinguished Achievement Award for Petroleum Engineering Faculty. He is also a member in the editorial board of International Journal of Petroleum Engineering.

Mr. Sunil Kumar is doing his PhD in the field of surfactant induced enhanced oil recovery in Department of Petroleum Engineering, Indian Institute of Technology (ISM), Dhanbad. Earlier he did his Masters in Petroleum Engineering from the same Institute. He has published seven papers in reputed international Journals.

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Received: 2016-08-24
Accepted: 2017-01-17
Published Online: 2017-09-06
Published in Print: 2017-09-15

© 2017, Carl Hanser Publisher, Munich

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https://doi.org/10.3139/113.110514
Schlagwörter für diesen Artikel
Micellization; nonionic surfactant; critical micelle concentration (CMC); interfacial tension (IFT); contact angle

Artikel in diesem Heft

  1. Contents/Inhalt
  2. Contents
  3. Detergents/Cleaning
  4. Application of Glycerin in Liquid Laundry Detergents as an Example of Innovation in the Household Chemicals Industry
  5. Application
  6. Characterization of Pyrene Solubilization in Selective Micellar Media of Novel Bio-degradable Natural Surfactant Saponin (Extracted from Soap Nut) and Conventional Surfactant SDBS in Presence and Absence of Common Salt NaCl
  7. The Effect of pH on the Properties of a Cationic Bitumen Emulsifier
  8. The Role of Fatty Acids Functional Group in Morinda citrifolia L. on Surface Tension and Diffusion Performance into Ink Particles
  9. Physical Chemistry
  10. Effect of Some Vitamins of Group B (B1, B6, B12) on Micellar and Viscosity Properties of Anionic, Cationic and Nonionic Surfactants in Aqueous Solutions
  11. Phase Behavior and Solubilization of Microemulsions Containing C16mimBr with Different Oil-Water Ratios
  12. Thermodynamics of Micellization, Interfacial Behavior and Wettability Alteration of Aqueous Solution of Nonionic Surfactants
  13. Novel Surfactants
  14. Synthesis and Properties of a Novel Gemini Surfactant with Bis-piperidinium
  15. Surface Activities and Quantum Chemical Calculations for Different Synthesized Cationic Gemini Surfactants
  16. Effect of Novel Surfactant on the Growth Kinetics of Cobalt Nanoparticles
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