TABLE OF CONTENT CHAPTER CONTENT PAGE

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1 vii TABLE OF CONTENT CHAPTER CONTENT PAGE TITLE PAGE DECLARATION DEDICATION ACKNOWLEDGEMENT ABSTRACT ABSTRAK TABLE OF CONTENT LIST OF TABLES LIST OF FIGURES NOMENCLATURE LIST OF APPENDICES i ii iii iv v vi vii xi xiii xviii xx CHAPTER I INTRODUCTION 1.1 Historical Background of Membrane 1 Technology 1.2 Problem Statement Objectives of the Study Research Scopes 8

2 viii CHAPTER 2 LITERATURE REVIEW 2.1 Overview of Membrane Technology Type of Membranes Membrane Separation Processes Advantages of Membranes Processes Ultrafiltration Membranes Fundamental of Ultrafiltration Membranes History of Ultrafiltration Membranes Mechanism of Membrane Transport 22 Through Ultrafiltration Membrane Rejection, Concentration Polarization and Membrane Fouling Rejection Concentration Polarization and Membrane Fouling Development of Asymmetric Hollow Fiber Ultrafiltration Membrane for Cyclodextrin Separation Enzyme and other Separation in 25 Biotechnology Membrane Separation in Biotechnology Hollow Fiber Membranes and Its 31 Common Principles Membrane Formation by Phase Inversion Process Wet Phase Inversion Process Dry/Wet Phase Inversion Process Production of Hollow Fiber Ultrafiltration Membranes

3 ix Hollow Fiber Spinning Phase Inversion Effects in 53 Hollow Fiber Membrane Formation Rheological Factors in Hollow Fiber Membrane Production 57 CHAPTER 3 METHODOLOGY 3.1 Experimental Design Dope Formulation Polymer Solvent, Nonsolvent and Polymer Additive Turbidimetric Titration Method Preparation of Polymer Solution Dry/Wet Spinning Process Solvent Exchange Process Practicalities of Fiber Spinning Preparation of Hollow Fiber Membrane Modules 75 (Potting-up) 3.7 Measurement of Membrane Flux and Rejection Plane Polarized Infrared Fourier Transform 79 Spectroscopy 3.9 Scanning Electron Microscopy (SEM) 81 CHAPTER 4 RESULTS AND DISCUSSION 4.1 Hollow Fiber Membrane Performance Testing Effects of Bore Fluid on Membrane Performance and Morphology 82

4 x Effects of Polymer Concentration on Membrane Performance and Morphology Effects of Dope Extrusion Rate on Membrane Performance and Morphology CHAPTER 5 GENERAL CONCLUSIONS AND RECOMMENDATIONS FOR FUTURE WORK 5.1 General Conclusions Recommendations for Future Work 110 REFERENCES 112 PUBLICATIONS 122 APPENDIX 123 Appendix A-C

5 xi LIST OF TABLES TABLE NO. TITLE PAGE 2.1 Membrane at a glance Types and characteristics of widely practiced membrane processes Factors affecting hollow fiber morphology Materials used for polymer solution formulation Physical, mechanical and thermal properties of polyethersulfone (PES) Water activities of bore fluid solutions Hollow fiber ultrafiltration membrane spinning dimensions 3.5 Infrared bands of functional groups in polyethersulfone (PES) Effects of bore fluid on membrane performance Comparison of solution with different polymer concentration 4.3 Effect of polymer concentration on membrane performance 90 92

6 xii 4.4 Wall thickness, outer and inner diameter of hollow fiber membrane produced with different polymer concentration 4.5 Effects of dope extrusion rate on membranes performance 4.6 Wall thickness, outer and inner diameter of hollow fiber membrane

7 xiii LIST OF FIGURES FIGURE NO. TITLE PAGE 1.1 Basic of membrane separation process Asymmetric membrane consists of a very thin skin layer overlaying on a thick and highly porous sublayer Milestones in the development of ultrafiltration The sieve mechanism of ultrafiltration membrane Concentration polarization in ultrafiltration Types of hollow fiber membrane and its applications The structure of hollow fiber membrane Tube-in-orifice spinneret Spinneret faces: (a) segmented-arc design; (b) plug-inorifice design; (c) tube-in-orifice; (d) multi-annular design 2.9 Schematic depiction of the immersion precipitation process: P, polymer; S, solvent; NS, non-solvent Schematic ternary phase diagram for ternary system Ternary phase diagram of polymer/solvent/nonsolvent system 43

8 xiv 2.12 Schematic diagram of an isothermal ternary phase diagram showing the equilibrium tie-lines connecting equilibrium compositions on the binodal curve having polymer rich and polymer poor compositions indicated as PR and PP respectively 2.13 Schematic representation of diffusion paths initiating near the binodal boundary and potentially penetrating to the metastable (nucleation and growth) region (A ), the unstable (spinodal decomposition) region (A ) or the solidus tie-line (A ) where the morphology is vitrified immediately upon phase separation and unable to evolve Hollow fiber spinning technique Schematic diagram of die swell phenomenon in hollow fiber spinning 3.1 Critical issues controlling successful ultrafiltration membranes Experimental design The structure of polyethersulfone used for asymmetric hollow fiber preparation Apparatus for turbidimetric titration Equipment used for polymer solution preparation Steps involved in the preparation of asymmetric membrane according to the dry/wet phase separation process 3.7 Schematic diagram of hollow fiber spinning system: (1) nitrogen cylinder; (2) dope reservoir; (3) gear pump; (4) 71 72

9 xv on-line filter, 7 mm; (5) syringe pump; (6) spinneret; (7) forced convective tube; (8) roller; (9) wind-up drum; (10) refrigeration/heating unit; (11) coagulation bath; (12) washing/treatment bath; (13) wind-up bath; (14) schematic spinneret 3.8 Schematic diagram of a general fiber spinning process Schematic diagram of hollow fiber membrane module and housing 3.10 Testing rig for hollow fiber ultrafiltration membrane module: (1) feed tank; (2) osmotic pump; (3) control valve; (4) flow meter; (5) pressure gauge; (6) hollow fiber membrane module; (7) beaker for collecting permeate 4.1 The rejection of the membrane versus molecular weight of tested solutes for membrane spun at dope extrusion rate of 3.5 cm 3 /min for both type of bore fluid (BF) 4.2 The overall cross-section of hollow fiber membranes: (a) and (b) for bore fluid of distilled water and (c) and (d) for a mixture of potassium acetate and distilled water (Magnification: 110x) 4.3 Inner and outer edge of cross-section of hollow fiber membranes: (a) and (b) for bore fluid of distilled water and (c) and (d) for a mixture of potassium acetate and distilled water (Magnification: 400x) 4.4 The rejection of the membranes versus molecular weight of tested solutes for membrane spun at 3.5 cm 3 /min of dope extrusion rate The overall cross-section of hollow fiber membranes: 94

10 xvi (a) for solution DS1, (b) for solution DS2 and (c) for solution DS3 (Magnification: 110x) 4.6 Inner and outer edge cross-section of hollow fiber membranes: (a) for solution DS1, (b) for solution DS2 and (c) for solution DS3 (Magnification: 400x) 4.7 Effect of dope extrusion rate on PWP of hollow fiber ultrafiltration membrane Rejection of membrane at different dope extrusion rate Flux of membrane at different dope extrusion rate The rejection of the membranes versus molecular weight of tested solutes for membrane spun at 3.5 cm 3 /min of dope extrusion rate 4.11 The overall cross-section of hollow fiber membranes at different dope extrusion rate (Magnification: 110x) 4.12 Inner and outer edge cross-section of hollow fiber membranes at different dope extrusion rate (Magnification: 400x) 4.13 Scanning electron micrographs of membrane surface at different dope extrusion rate (Magnification: 5000x) 4.14 Plane-polarized infrared spectra parallel (darker line) and perpendicular (lighter line) to shear direction for membrane spun at high dope extrusion rate (3.5 cm 3 /min) 4.15 Plane-polarized infrared spectra parallel (darker line) and perpendicular (lighter line) to shear direction for membrane spun at low dope extrusion rate (2.5 cm 3 /min)

11 xvii 4.16 A linear dichroism spectrum (subtraction of parallel spectrum to perpendicular spectrum) for membrane spun at low dope extrusion rate (2.5 cm 3 /min) (lighter line) and high dope extrusion rate (3.5 cm 3 /min) (darker line) 107

12 xviii NOMENCLATURE A - Surface area of hollow fiber membranes (cm 2 ) A sp - Cross sectional area of the spinneret (cm 2 ) DER - Dope extrusion rate (cm 3 /min) f - Observed/apparent solute rejection (%) f o - Actual/true solute rejection (%) g - Airgap distance (cm) J - Permeate flux (L/m 2.h) JS - Jet stretch ratio or draw ratio MW - Molecular weight (dalton) MWCO - Molecular weight cut-off (dalton) p - Pressure (bar) p o - Atmospheric pressure (bar) p - Transmembrane pressure (bar) PR - Product rate PWP - Pure water permeation rate (L/m 2.h) Q - Volumetric flow rate (L/h) S - Standard Deviation T - Temperature (K) T g - Glass transition temperature ( o C) v - Permeation velocity of product V o - Spine line initial velocity (cm/s) V f - Spine line final velocity (cm/s) g - Shear rate (s -1 ) i - Component i j - Component j T - Total

13 xix BF - Bore fluid DS 1 - Polymer solution 1 DS 2 - Polymer solution 2 DS 3 - Polymer solution 3 D - Diameter C p - Solute concentration of permeate (mg/l) Cf - Solute concentration of feed (mg/l) V - Permeate volume (L) t - Time (h) PVP - Polyvinylpyrrolidone PEG - Poly (ethylene) glycol PES - Polyethersulfone NMP - 1-methyl-2-pyrrolidone NSA - Nonsolvent additive TOC - Total organic carbon analyzer SEM - Scanning electron microscope FTIR - Fourier transform infra-red spectroscopy VEP - Volume extrusion from pump (cm 3 /rev) CD - Cyclodextrin CGT - Cyclodextrin glycosyltransferase RO - Reverse Osmosis NF - Nanofiltration UF - Ultrafiltration MF - Microfiltration BFIR - Bore fluid injection rate (cm 3 /min)

14 xx LIST OF APPENDICES APPENDIX TITLE PAGE A Experimental Data 123 B Feed and Permeate Concentration Measured from Total Organic Carbon Analyzer 149 C Spinning Conditions 151