Surfactants in Chemical/Process Engineering

Wasan

• Publisher: CRC Press
• Year: 2017
• Print ISBN: 9780824778309
• eBook ISBN: 9781351412513
• Edition: 1
• Topic: Physical Sciences
• Subtopic: Chemistry
• Index: Chemistry

The first reference to link chemical engineering technologies and surfactant science in suchbreadth of focus, Surfactants in Chemical/Process Engineering features contributionsby major authorities in chemical engineering whose applications have opened important newfields for surfactant use. These applications include dispersion science, separation processes, oilrecovery, microemulsions, and environmental control.This volume discusses ultrafiltration processes, flotation, metal extractions, and more...examines surfactants in process streams for such industrial separations as micellar-enhancedultrafiltration, adsorbent regeneration, micellar extractions, and oiVwater demulsification...describes methodologies for separations of fatty acids, metals, minerals and impurities, solvents, and hydrocarbons for cost-saving industrial and consumer product manufacture...details techniques for developing and optimizing formulations for superior agricultural plantcontrol or enhancement systems, micro- and macroemulsions, and liquid surfactant membranes... and looks closely at emulsion polymers in soil stabilizations, protective coatings, sealants, adhesives, textile processing, paper finishing, specialty concretes, and tire manufacture.

1

Dilatational Properties of Adsorbed Surfactant Interfaces and Their Applications

D. A. Edwards and Darsh T. Wasan Illinois Institute of Technology, Chicago, Illinois

I. Introduction

II. Dynamic Surface Properties (Surface Rheology)

III. Surface Dilatational Properties

IV. Applications

A. Foam Rheology

B. Enhanced Oil Recovery

C. Foam Stability

D. Emulsion Stability

V. Summary

References

I Introduction

The adsorption of surfactant at a fluid-fluid interface has long been known to alter equilibrium interfacial properties. However, in practice, equilibrium is an inevitable abstraction: the limiting case of actual dynamic processes which occur near, at, and across an interface. Dynamic interfacial properties, which are required to quantify practical dynamic surface problems, are less well known.

Dynamic interfacial properties may be classified in terms of shear properties and dilatational properties. The former, which typically include the surface shear viscosity and the shear elasticity, have been shown relevant to such dynamic phenomena as foam and emulsion stability, coalescence, and interfacial mass transfer [1—3].

We have recently undertaken a fundamental research program to investigate the less understood but more significant dilatational properties, such as the dynamic surface/interfacial tension, the dilatational modulus, and the surface dilatational viscosity. Our objective in this research has been first, to develop techniques to measure the dilatational properties, and second, to investigate (both experimentally and theoretically) the correlation between the dynamic surface/interfacial properties and foam rheology, foam flow in EOR processes, foam stability, and emulsion stability.

In this chapter we summarize the current results from our research efforts, beginning with a simple derivation of the relation between surface and bulk-phase hydrodynamics (in which context dynamic surface properties are defined), followed by a detailed consideration of surface dilatational properties, and concluding with the various theoretical and experimental results that we have obtained for dilatational surface properties and their application to dynamic interfacial phenomena.

II Dynamic Surface Properties (Surface Rheology)

Surface rheology is the study of interfacial response to deformation. Often we consider the deformational response of the surface as defined by a single stress coefficient: the surface tension. However, when surfactant adsorbs to the fluid-fluid interface, an intrinsic rigidity may arise, introducing beyond the tensile response to deformation, a damping or viscous response which cannot be defined completely by the surface tension, requiring coefficients of surface viscosity.

Although the origin of surface tension and surface viscosities is quite intuitive, the surface st...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright
• Preface
• Contributors
• 1. DILATATIONAL PROPERTIES OF ADSORBED SURFACTANT INTERFACES AND THEIR APPLICATIONS
• 2. THE EFFECT OF SURFACE-ACTIVE AGENTS IN DISTILLATION PROCESSES
• 3. SURFACTANT-BASED TREATMENT OF AQUEOUS PROCESS STREAMS
• 4. LIQUID SURFACTANT MEMBRANES FOR METAL EXTRACTIONS
• 5. SURFACTANTS IN AQUEOUS EMULSIFICATION SEPARATION OF OLEIC AND STEARIC ACIDS
• 6. SURFACTANTS IN FLOTATION
• 7. SURFACTANTS IN HERBICIDE DISPERSIONS
• 8. THE ROLE OF SURFACTANTS IN EMULSION POLYMERIZATION
• 9. MICROEMULSIONS: FORMATION, STRUCTURE, PROPERTIES, AND NOVEL APPLICATIONS
• 10. IMPORTANCE OF SURFACTANTS AND SURFACE PHENOMENA ON SEPARATING DILUTE OIL-WATER EMULSIONS AND DISPERSIONS
• Index