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Production of Activated Carbons from Pyrolytic Char for Environmental Applications

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Production of Activated Carbons from Pyrolytic Char for Environmental Applications Western University Scholarship@Western Electronic Thesis and Dissertation Repository 7-27-2015 12:00 AM Production Of Activated Carbons From Pyrolytic Char For Environmental Applications Anastasia Colomba The University of Western Ontario Supervisor Dr. Franco Berruti The University of Western Ontario Joint Supervisor Dr. Cedric Briens The University of Western Ontario Graduate Program in Chemical and Biochemical Engineering A thesis submitted in partial fulfillment of the equirr ements for the degree in Doctor of Philosophy © Anastasia Colomba 2015 Follow this and additional works at: https://ir.lib.uwo.ca/etd Part of the Chemical Engineering Commons Recommended Citation Colomba, Anastasia, "Production Of Activated Carbons From Pyrolytic Char For Environmental Applications" (2015). Electronic Thesis and Dissertation Repository. 2978. https://ir.lib.uwo.ca/etd/2978 This Dissertation/Thesis is brought to you for free and open access by Scholarship@Western. It has been accepted for inclusion in Electronic Thesis and Dissertation Repository by an authorized administrator of Scholarship@Western. For more information, please contact [email protected]. Production Of Activated Carbons From Pyrolytic Char For Environmental Applications (Thesis format: Monograph) by Anastasia Colomba Graduate Program in Engineering Science Department of Chemical and Biochemical Engineering A thesis submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy The School of Graduate and Postdoctoral Studies The University of Western Ontario London, Ontario, Canada © Anastasia Colomba 2015 Abstract Biomass pyrolysis has the potential to become a major component of future biorefineries, since biomass is cracked to produce gases, liquid products (bio-oil) and solid products (bio-char). In order for the process to be economically feasible, it is necessary to obtain the maximum value from each stream, thus no by-product can be regarded as a waste. Bio-char is normally regarded as a by-product of fast pyrolysis, which is optimized to target bio- oil production. However, there are many potentially attractive applications for it: for example, it can be used for the production of activated carbons, which are the most commonly used adsorbent materials. In this study, a new reactor technology developed at ICFAR, the Jiggled Bed Reactor (JBR) is employed as a fast and reliable tool for the optimization of the production of activated carbons from biomass. Due to its excellent heating system, both slow and fast pyrolysis conditions can be achieved, and activation can be carried out. The results obtained in the JBR show good comparison with larger scale reactors, thus allowing the screening of new pyrolysis and activation conditions as well as different feedstocks in a fast and reliable way. The impact of the type of feedstock, activation and pyrolysis conditions (fast/slow) on the final product characteristic and activation kinetics are studied. Finally, the performance of activated carbons produced in the JBR as adsorbents is evaluated for different environmental applications, such as the removal of ammonia and mercury from wastewater and of naphthenic acids from Oil Sands Process-affected water (OSPW). In particular, activated carbon produced from Kraft lignin is shown to outperform commercial activated carbon for wastewater treatment applications. Keywords Activated carbons, biomass, Kraft lignin, pyrolysis, Jiggled Bed Reactor, bio-char, mercury, naphthenic acids ii Acknowledgments First, I would like to acknowledge for my supervisors, Dr. Franco Berruti and Dr. Cedric Briens. Thank you for accepting me into your research group, always believing in me and pushing me to do my best. Thank you for your time and support and for the good times while travelling together. I would also like to acknowledge the people without whom this work would have not been possible: Students, Post-Docs and staff at ICFAR and in particular Valentina Lago, Liliana Pardo and Carolina Morales, Dr. Roel Westerhof, Dr. Pietro Palmisano and Dr. Dongbing Li, Caitlin Marshall, Rob Taylor and Karen McDonalds, for your help and for sharing this journey with me. You all are part of the happiest memories of these years. Ying Zhang from CBE for the help with the BET measurements. Dr. Ajay Dalai, for inviting me to your lab at the University of Saskatchewan and sharing with me your extensive experience. Thank you for your jokes and your contagious laughter. Dr. Rambabu Nedunuri, for the time you dedicated to me during my stay at the University of Saskatchewan. Thank you for your immense kindness and for cooking the best biryani for me. My appreciation also goes to BioFuelNet Canada for the funding and for providing me with two HQP Travel Awards to attend conferences and meetings and the Exchange Award to visit Dr. Dalai’s lab in Saskatoon. Finally, I would like to acknowledge my family and my friends for their unconditioned love and support. Last, but not least, Mitesh Chaudhari: the most special thanks is for you, for always being by my side in both the tough and happy moments I experienced during the last years. Thank you for pushing me to always see the good in life and never give up. Thank you for loving me. Your presence has been the biggest support in my PhD journey. iii Dedication In loving memory of my Godfather and Uncle Maurizio. iv Table of Contents Abstract ........................................................................................................................................... ii Keywords ........................................................................................................................................ ii Acknowledgments.......................................................................................................................... iii Dedication ...................................................................................................................................... iv Table of Contents ............................................................................................................................ v List of Tables .................................................................................................................................. x List of Figures ............................................................................................................................... xii Abbreviations, Symbols, Nomenclature .................................................................................... xviii Chapter 1 ......................................................................................................................................... 1 1. Introduction .......................................................................................................................... 1 1.1 Motivation ........................................................................................................................ 1 1.2 What is Pyrolytic Bio-Char? ............................................................................................ 3 1.3 Possible Bio-Char Applications ....................................................................................... 3 1.4 Activated Carbons ............................................................................................................ 7 Current and perspective market........................................................................................ 7 Feedstocks for the production of activated carbons ......................................................... 9 Production processes ........................................................................................................ 9 1.5 Biomass Pyrolysis .......................................................................................................... 12 The pyrolysis process ..................................................................................................... 12 Reactors used for biomass pyrolysis .............................................................................. 13 1.6 Context and Scope of this Thesis ................................................................................... 15 1.7 Thesis Structure .............................................................................................................. 17 Chapter 2 ....................................................................................................................................... 19 2. Materials and Methodology ............................................................................................... 19 2.1 Feedstocks ...................................................................................................................... 19 v 2.2 Experimental Set Up: the Jiggled Bed Reactor (JBR) ................................................... 22 2.3 Pyrolysis and Activation Procedures.............................................................................. 27 Batch pyrolysis experiments (with CO2 activation) ....................................................... 27 Fast pyrolysis experiments ............................................................................................. 28 Activation experiments with wet gases .......................................................................... 29 Production of HNO3 treated activated carbons .............................................................. 29 Reproducibility ..............................................................................................................
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