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Pushpa Datta Upreti PDF

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FACULTY OF HEALTH AND LIFE SCIENCES REMEDIATION OF TEXTILE AND MINING INFLUENCED EFFLUENTS USING NOVEL HETEROGENEOUS PAN CATALYST AND MODIFIED PAN MESH A thesis submitted in the partial fulfilment for the degree of Doctor of Philosophy (Ph.D.) in Environmental Technology By Pushpa Datta Upreti Supervisor: Prof. Dr. Katherine D. Huddersman March 2018 DEDICATION I would like to dedicate this thesis in memory of my beloved late parents: Mr. Ganesh Datta Upreti Mrs. Maheshwori Upreti Who sacrificed own happiness for my success and could not be there when it is happening!!! II ACKNOWLEDGEMENT First, I would like to express my deepest and sincere gratitude to my supervisor Prof. Dr. Katherine D. Huddersman for her continual invaluable guidance and support without which this project would not come to this stage. I am deeply indebted to her for the opportunities, from the laboratory to the pilot trials, provided to me. Her support was more than one could hope for from a supervisor, an exceptional supervisor. Her efforts enlightened me with life-long research skills. I would like to thank my second supervisor Prof. Dr. Martin Grootveld. I would like to express my sincere thanks to Dr. George Tangyie Chi for his invaluable feedback and guidance. I would like to thank Dr. Walkiria Schlindwein for feedback and discussions during annual reviews. I would like to thank technicians, especially Unmesh Deshai, Nazmin Juma and Rachel Armitage, of the Faculty of Health and Life Sciences for their support. I would like to remember my colleagues Aghogho Ekpruke, Emmanuel Ushie, Dr. Caroline Akinremi, Elmajid Yusuf and Dr. Leo Ihonre Asuelimen in the research group for their friendship and stress-free friendly environment making this programme memorable. I am deeply indebted to my family, Dhruba Datta Upreti – brother; Apsara Upreti – sister- in-law; Barsha Belbase – wife; Avani Upreti – niece; Samriddha Upreti – son and Avan Upreti – nephew for their love and always being there to support and encourage me. I would like to appreciate all the relatives, friends and social committee co-workers for their encouragement and positive vibes. I would like to thank Innovate UK for the opportunity of innovation voucher and Jersey Dyer, Leicester for the part of SME in the scheme. I would like to express my sincere gratitude to The Coal Authority (CA) for managing the sponsorship of the metal removal project from the Department for Environment, Food & Rural Affairs (DEFRA). My special thanks goes to Isla Ismail, the then project manager from CA. I would like to appreciate all the related staff from The CA, The Environment Agency, Severn Trent Services and Integrated Water Services for their help. III PUBLICATION A part of chapter six of this research has led to the publication of the following conference proceeding. Upreti, Pushpa; Tangyie, George Chi; Huddersman, Katherine; Smail, Isla (2016): Field trial of an ion exchange based metal removal technology in the treatment of mine waters. – In: Drebenstedt, C. & Paul, M.: IMWA 2016 – Mining Meets Water – Conflicts and Solutions. – p. 828 – 835; Freiberg / Germany (TU Bergakademie Freiberg). IV ABSTRACT The effectiveness of a modified PAN catalyst and hydrogen peroxide system in the treatment of textile effluent and a modified ion exchange PAN mesh in the remediation of non-coal mine drainage was investigated. The results show a tremendous potential in the treatment of such wastewaters. The treatment process for textile effluent was optimized in batch mode of operation. The influence of pH and catalyst was more pronounced compared to that of H O . At optimum 2 2 conditions, 99.5 % decolourization and 91.9 % loss of aromaticity and 70 % mineralization were achieved in 100 minutes. The sorption of dye onto the catalyst is favourable and can be best described by a Langmuir adsorption isotherm model. The model predicts a maximum adsorption capacity for the PAN catalyst as 0.68 mg of RO16 per gram of catalyst. A direct relationship between pH, temperature and iron leaching was established. The leached iron has no significant contribution, by means of homogeneous catalysis, in the removal of dye. The system was successful in treating a real dye-bath effluent that was much more concentrated than usual textile effluents. The continuous flow treatment in a prototype of a rotating discs contactor revealed that 99.2 %, 73 %, 64.4 % and 50 % removal efficiencies for decolourization, loss of aromaticity, COD and mineralization at optimum conditions. The breakthrough of the system occurred after 50 days. The system was successfully regenerated in-situ three times and the lifetime of the catalyst extended to 103 days in total, decolourizing 25.3 g of RO16 dye from 546.7 L solution. The deactivation of catalyst occurred mainly due to the loss of iron and partially due to loss of functional groups that ligate iron. Similar to the batch experiments, the leached iron, in continuous flow experiment, has insignificant contribution in removing dye through homogeneous catalysis. The ion exchange capacity of the modified PAN fibre was determined though acid-base titration. The sorption of zinc onto ion exchange mesh is favourable and can be best described by Langmuir adsorption isotherm model. The pH of the medium was found to be the most influential parameter with maximum sorption observed at pH ≥ 5.5 at contact time ≥ 4 hours in batch mode of operation. A pilot scale field trial was performed to remediate mine effluent with elevated concentration of zinc, cadmium and lead demonstrates a tremendous potential applicability. According to analyses by UKAS accredited laboratory, the 170 days long trial successfully removed 5.59 kg, 8.53 g and 18.18 g of zinc-total, cadmium-total and lead-total from 131.46 m3 of mine effluent. The system also removed suspended solids, iron, copper, arsenic, nickel, aluminium, boron, manganese and nitrate (NO -N). The performance of the system was not 3 affected by the in-situ regeneration and seasonal variation in temperature. The best performance of the system was observed when the contact time ≥ 1.33 hours. The metal removal mechanism was ion exchange initiated (co)precipitation / sorption of metals onto the surface of ion exchange mesh. This technology can be applied in the remediation of all type of mine waters though pre-treatment to adjust pH and alkalinity may be needed. V TABLE OF CONTENT Dedication.......................................................................................................... II Acknowledgement ........................................................................................... III Publication....................................................................................................... IV Abstract ............................................................................................................ V Table of Content .............................................................................................. VI List of Figures ............................................................................................... XVI List of Tables ............................................................................................... XXIII List of Appendices .......................................................................................XXV List of Abbreviations ..................................................................................XXVI 1. Introduction ................................................................................................ 1 1.1. Introduction to the thesis ................................................................................. 2 1.2. Problem statement – Textile industry effluents................................................ 2 1.2.1. Solution for the treatment of textile effluents ............................................ 4 1.3. Problem statement – mining influenced effluents ............................................ 5 1.3.1. Remediation of mining influenced effluents .............................................. 6 1.4. Aims and objectives ........................................................................................ 7 1.4.1. Objectives – treatment of textile effluents ................................................ 7 1.4.2. Objectives - remediation of mining influenced effluents ........................... 7 1.5. Thesis structure .............................................................................................. 8 2. Literature Review: Treatment of Textile Effluents ................................. 10 2.1. Dyes: definition and history ........................................................................... 11 2.1.1. Chemical structure of dye and component responsible for dye colour .. 12 2.1.2. Classification of dyes ............................................................................. 13 2.1.2.1. Azo dyes ........................................................................................ 14 2.1.2.1.1. Reactive dyes ............................................................................. 15 2.1.3. Worldwide consumption of dyes ............................................................ 16 VI 2.1.4. Characterization of textile effluent .......................................................... 17 2.1.5. Environmental exposure and fate of dyes .............................................. 17 2.1.6. Toxicity and effects of dyes on biological system ................................... 20 2.1.7. Environmental legislation for water quality ............................................. 23 2.1.8. Reactive Orange 16 – the model dye ..................................................... 24 2.2. Treatment technologies for dye removal ....................................................... 26 2.2.1. Biological treatment methods ................................................................. 26 2.2.2. Conventional physicochemical methods ................................................ 28 2.2.2.1. Coagulation and Flocculation (C & F) ............................................. 28 2.2.2.2. Adsorption ...................................................................................... 29 2.2.2.3. Ion exchange .................................................................................. 30 2.2.2.4. Filtration ......................................................................................... 30 2.2.2.5. Oxidation methods .......................................................................... 30 2.2.3. Advanced Oxidation Processes (AOPs) ................................................ 31 2.2.3.1. Fenton oxidation ............................................................................. 33 2.2.3.1.1. Conventional Fenton oxidation ................................................... 35 2.2.3.1.2. Modified Fenton oxidation .......................................................... 38 2.2.3.1.3. Homogeneous versus heterogeneous Fenton oxidation catalysis... ................................................................................................... 39 2.2.3.1.4. Factors affecting Fenton based processes ................................. 41 2.2.3.1.5. Influence of pH ........................................................................... 42 2.2.3.1.6. Influence of hydrogen peroxide concentration ............................ 44 2.2.3.1.7. Influence of amount of catalyst ................................................... 45 2.2.3.1.8. Influence of temperature ............................................................. 45 2.2.3.1.9. Influence of substrate concentration ........................................... 45 2.2.3.2. Modified fibrous polyacrylonitrile (PAN) catalyst ............................. 46 3. Literature Review – Remediation of mining influenced effluents ....... 48 3.1. Mining and the environment .......................................................................... 49 VII 3.1.1. The chemistry of mine waters ................................................................ 52 3.1.1.1. Mine water from the coal mine ........................................................ 53 3.1.1.2. Mine water from the metal mines .................................................... 57 3.1.1.2.1. Zinc (Zn) ..................................................................................... 59 3.1.1.2.2. Cadmium (Cd) ............................................................................ 59 3.1.1.2.3. Lead (Pb) ................................................................................... 60 3.2. Environmental legislation for water quality .................................................... 61 3.3. Mine water treatment technologies ............................................................... 62 3.3.1. Passive treatment methods ................................................................... 62 3.3.1.1. Anoxic Limestone Drains (ALDs) .................................................... 63 3.3.1.2. Oxic limestone drains (OLDs) ......................................................... 64 3.3.1.3. Reducing and alkalinity producing system (RAPS) ......................... 64 3.3.1.4. Constructed wetlands ..................................................................... 65 3.3.1.5. Permeable Reactive Barriers (PRBs) .............................................. 66 3.3.2. Active treatment methods ...................................................................... 67 3.3.2.1. Oxidation ........................................................................................ 68 3.3.2.1.1. Aeration ...................................................................................... 68 3.3.2.1.2. Biochemical oxidation by RBC .................................................... 69 3.3.2.1.3. Chemical oxidation ..................................................................... 69 3.3.2.2. Dosing with alkali ............................................................................ 69 3.3.2.3. Sedimentation ................................................................................ 72 3.3.2.4. Sulfidization and biodesalination ..................................................... 72 3.3.2.5. Membrane processes ..................................................................... 72 3.3.2.6. Extraction ....................................................................................... 73 3.3.2.7. Sorption .......................................................................................... 73 3.3.2.7.1. Adsorption .................................................................................. 74 3.3.2.8. Ion exchange .................................................................................. 75 3.3.2.8.1. Ion exchangers (Resins and Fibres) ........................................... 77 VIII 3.3.2.8.2. Properties of ion exchange resins............................................... 77 3.3.2.8.3. Ion exchange fibres .................................................................... 77 3.3.2.8.3.1. Modified Polyacrylonitrile (PAN) fibre ................................... 78 4. Optimization of dye treatment process .................................................. 81 4.1. Introduction ................................................................................................... 82 4.2. Aim and objectives ....................................................................................... 82 4.3. Materials and methods ................................................................................. 83 4.3.1. Reagents ............................................................................................... 83 4.3.2. Materials and instruments ...................................................................... 84 4.3.3. Analytical parameters and methodology ................................................ 85 4.3.3.1. pH .................................................................................................. 86 4.3.3.2. Decolourization of Reactive Orange 16 (RO16) .............................. 86 4.3.3.3. Mineralization ................................................................................. 87 4.3.3.4. Chemical Oxygen Demand (COD) .................................................. 88 4.3.3.5. Sorption of RO16 onto the modified PAN catalyst ........................... 89 4.3.3.6. Loss of catalyst (≈ iron leaching) .................................................... 90 4.3.3.7. Homogeneous catalysis .................................................................. 90 4.3.3.8. Effect of dissolved oxygen on decolourization of RO16 .................. 91 4.3.3.9. Sampling and treatment of Dye-bath effluent .................................. 91 4.4. Experimentation ............................................................................................ 92 4.4.1. Preparation of the catalyst ..................................................................... 92 4.4.1.1. Washing of catalyst ........................................................................ 92 4.4.1.2. pH normalization of modified PAN catalyst ..................................... 92 4.4.2. Experimental procedures ....................................................................... 93 4.5. Results and discussions ............................................................................... 94 4.5.1. UV-Vis spectra of RO16 ........................................................................ 94 4.5.2. Stability of RO16 .................................................................................... 96 4.5.3. Sorption of Reactive Orange 16 onto the catalyst .................................. 97 IX 4.5.3.1. Equilibrium adsorption isotherms .................................................. 100 4.5.3.1.1. The Langmuir isotherm model .................................................. 100 4.5.3.1.2. Freundlich adsorption isotherm model ...................................... 103 4.5.3.1.3. Selection of the best-fit adsorption model ................................. 105 4.5.3.1.4. Influence of pH on sorption of RO16 ......................................... 106 4.5.4. Optimization of Reactive Orange 16 degradation process ................... 108 4.5.4.1. Influence of amount of modified PAN catalyst ............................... 108 4.5.4.2. Influence of hydrogen peroxide on degradation of RO16 .............. 111 4.5.4.2.1. Effect of dissolved oxygen on the decolourization of RO16 ...... 119 4.5.4.3. Influence of pH on degradation of RO16 ....................................... 120 4.5.4.4. Influence of initial concentration of substrate (RO16) .................... 124 4.5.4.5. Influence of temperature on degradation of RO16 ........................ 127 4.5.4.6. Amount of catalyst loss with respect to process parameters ......... 129 4.5.4.7. Extent of decolourization and mineralisation of RO16 ................... 132 4.5.4.8. Homogeneous versus heterogeneous catalyses........................... 133 4.5.4.9. Treatment of effluent from the dye-bath ........................................ 135 4.5.4.9.1. The sample and the constituents .............................................. 135 4.5.4.9.2. UV-Vis scanning of dyes and effluent sample ........................... 136 4.5.4.9.3. Catalysis of dye-bath effluent ................................................... 137 4.5.4.9.3.1. Initial assessment for the catalysis of dye-bath effluent ...... 137 4.5.4.9.3.2. Improvement of the treatment process ............................... 137 4.6. Summary .................................................................................................... 139 5. Continuous Flow Treatment of Reactive Orange 16 (RO16) and Lifetime of the Modified PAN Catalyst ....................................................................... 142 5.1. Introduction ................................................................................................. 143 5.2. Aim and objectives ..................................................................................... 145 5.3. Materials and methods ............................................................................... 146 5.3.1. Reagents ............................................................................................. 146 X

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has no significant contribution, by means of homogeneous catalysis, in the removal of dye. Figure 4-7: Structure of N-acetyl gamma acid. Figure 4-18: UV-Vis spectra comparing RO16 with and without H2O2. destructive methods, for example, advanced oxidation processes (AOPs), are the.
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