PURDUE UNIVERSITY GRADUATE SCHOOL Thesis Acceptance This is to certify that the thesis prepared By Entitled Complies with University regulations and meets the standards of the Graduate School for originality and quality For the degree of Final examining committee members , Chair Approved by Major Professor(s): Approved by Head of Graduate Program: Date of Graduate Program Head's Approval: Dong-Hee Kang Phytoremediation of Iron Cyanide Complexes in Soil and Groundwater. Doctor of Philosophy M. K. Banks C. Johnston R.S. Govindaraju P. Schwab 31 July 2006 M. K. Banks Darcy Bullock UMI Number: 3239788 3239788 2007 UMI Microform Copyright All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. ProQuest Information and Learning Company 300 North Zeeb Road P.O. Box 1346 Ann Arbor, MI 48106-1346 by ProQuest Information and Learning Company. i PHYTOREMEDIATION OF IRON CYANIDE COMPLEXES IN SOIL AND GROUNDWATER A Dissertation Submitted to the Faculty of Purdue University by Dong-Hee Kang In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy August 2006 Purdue University West Lafayette, Indiana ii ACKNOWLEDGMENTS There are many people who I would like to thank for their contribution to this dissertation. First and foremost, I would like to thank my advisor, Professor Katherine Banks of the School of Civil Engineering for her continuous support of my Ph.D program. Professor Banks always gave me clarity when I had a question about my research or writing. She consistently allowed this dissertation to be my own work and guided me in the right direction. She showed me different ways to approach a research problem and the need to be persistent to accomplish any goal. She is most responsible for assisting me with the writing of this dissertation as well as directing me towards a challenging research project. Without her encouragement and constant guidance, I could not have finished this dissertation. I sincerely want to thank Professor Paul Schwab of the Department of Agronomy for his assistance with the statistical analyses and analytical methods development. He always made me comfortable and provided truthful advice about my future when I stopped by his office. Thanks also to Professor Rao S. Govindaraju of the School of Civil Engineering for asking insightful questions to help me think through my research direction. I wish to thank Professor Cliff Johnston of the Department of Agronomy who offered guidance and research direction on the adsorption experimental design. In addition, I would like to thank Professor James Alleman, Chair of iii the Department of Civil, Construction, and Environmental Engineering at Iowa State University for instruction on the toxicity assays. I would like to acknowledge my colleagues from the Banks research group for their assistance and support during my doctoral work. I would especially like to thank James Hunter, who gave me confidence when I doubted myself and helped me develop innovative research ideas. (More importantly, he taught me to how to play hard and control stress!) I also would like to thank my fantastic coworker, Lee-Yen Hong, for her friendship, encouragement, and research discussions. Also, many thanks to my other friends at Purdue University for their support: Yong Sang Kim, Sybil Sharvelle, Agnes Szlezak, Eric McLamore, and Jason Hickey. I also appreciate the help provided by Dr. Changhe Xiao with his patient explanations during instrument repair. Special recognition goes to Dr. Mi-Youn Ahn, who provided insightful comments and reviewed my work on very short notice. Also, thanks to Dr. Andrew R. Zimmerman (Assistant Professor of Geological Sciences at the University of Florida), who gave me useful information about oxidation and enzyme activity. I want to thank Professor Won Chul Cho of the Department of Civil Engineering at Chung-Ang University (Seoul, Korea) who was my MS advisor for his continuous support. Also, I appreciate the assistance of Dr. David Tsao (BP Corporation, IL) and Dr. Wang-Cahill Fan for guidance on the design of greenhouse study and financial support of the project. Finally, I would like to thank my lovely wife and best friend, Hye Jeong Lee, for her patience and for keeping my life in proper perspective and balance, and my parents for their endless encouragement and constant support. iv TABLE OF CONTENTS Page LIST OF TABLES vii LIST OF FIGURES ix LIST OF ABBREVIATIONS xi ABSTRACT xii CHAPTER 1. INTRODUCTION 1 CHAPTER 2. LITERATURE REVIEW 4 2.1. Manufactured Gas Plants Sites 4 2.2. Classification of Cyanide Compounds 6 2.3. Cyanide Toxicity 7 2.4. Solubility of Iron Cyanide Complexes 8 2.5. Fate and Transport of Cyanide 9 2.6. Microbial Degradation of Cyanide 11 2.7. Phytoremediation of Cyanide Contaminants 13 2.8. Modeling of Phytoremediation Processes 17 2.9. References 19 CHAPTER 3. DISSERTATION OBJECTIVES AND HYPOTHESES 33 CHAPTER 4. SELECTION OF PLANT VARIETIES FOR PHYTOREMEDIATION OF IRON CYANIDE COMPLEXES 35 4.1. Introduction 36 4.2. Materials and Methods 39 4.2.1. Soil Preparation 39 4.2.2. Plant Species 39 4.2.3. Germination Assay 40 4.2.4. Root Characteristics 41 4.2.5. Statistical Analysis 41 4.3. Results and Discussion 42 v Page 4.3.1. Germination. 42 4.3.2. Root Characteristics 44 4.4. Conclusions 45 4.5. References 47 CHAPTER 5. PHYTOREMEDIATION OF IRON CYANIDE COMPLEXES USING CYANOGENIC AND NON-CYANOGENIC PLANT SPECIES 56 5.1. Introduction 57 5.2. Materials and Methods 59 5.2.1. Soil Preparation 59 5.2.2. Plant Selection 60 5.2.3. Greenhouse Methods 60 5.2.4. Analysis of Cyanide 61 5.2.5. Toxicity Assay 62 5.2.6. Statistical Methods 63 5.3. Results and Discussion 64 5.4. Conclusions 68 5.5. References 70 CHAPTER 6. SORPTION OF IRON CYANIDE COMPLEXES ONTO CLAY MINERALS, MANGANESE OXIDES, AND SOIL 80 6.1. Introduction 81 6.2. Materials and Methods 83 6.2.1. Soil Preparation 83 6.2.2. Clay Mineral Preparation 83 6.2.3. Manganese Oxide Synthesis 84 6.2.4. Adsorption 84 6.2.5. Cyanide Analysis 85 6.2.6. Acid Extraction 85 6.2.7. CEC and AEC 86 6.3. Results and Discussion 87 6.4. Conclusions 90 6.5. References 92 CHAPTER 7. THE ROLE OF TRAMETES VILLOSA LACCASE ON OXIDATION AND ADSORPTION OF FERROCYANIDE 100 7.1. Introduction 101 7.2. Materials and Methods 103 7.2.1. Materials 103 7.2.2. Enzyme Reactions 104 7.2.3. Adsorption Assessment 104 vi Page 7.2.4. Cyanide Analysis 105 7.2.5. Laccase Analysis 106 7.3. Results and Discussion 106 7.4. Conclusions 110 7.5. References 111 CHAPTER 8. EFFECT OF PLANTS ON LANDFILL LEACHATE CONTAINING CYANIDE AND FLUORIDE 120 8.1. Introduction 121 8.2. Description of Field Site 125 8.3. Materials and Methods 128 8.3.1. Plant Selection 128 8.3.2. Soil and Leachate Analysis 128 8.3.3. Fluoride and Cyanide Adsorption 129 8.3.4. Greenhouse Study 130 8.3.5. Cyanide Analysis for Soil and Plant Biomass 130 8.3.6. Fluoride Analysis for Soil and Plant Biomass 131 8.3.7. Assessment of Root Characteristics 132 8.3.8. Statistical Analysis 133 8.4. Results and Discussion 133 8.4.1. Leachate Toxicity 133 8.4.2. Root Characteristic 137 8.4.3. Fluoride and Cyanide Adsorption 138 8.4.4. Soil pH 138 8.4.5. Fluoride Concentration 140 8.4.6. Cyanide Concentration 141 8.5. Conclusions 142 8.6. References 144 CHAPTER 9. CONCLUSIONS AND FUTURE RESEARCH 165 9.1. Conclusions 165 9.2. Future Research 167 APPENDIX 169 VITA 196 vii LIST OF TABLES Table Page Table 2.1 Total Cyanide Concentrations in Contaminated Soil and Groundwater 25 Table 2.2 Environmental Cyanide Compounds 26 Table 2.3 Potential Risks from Daily Exposure to Cyanide Compounds 27 Table 2.4 Equilibrium Reactions and Constants (log K o ) 28 Table 2.5 Adsorption of Iron Cyanide Complexes 29 Table 2.6 Plants Used in Phytoremediation Applications 30 Table 2.7 Phytoremediation of Cyanide 31 Table 4.1 Soil Characteristics 50 Table 4.2 Plant Varieties 51 Table 4.3 Germination Assays 52 Table 4.4 Root Characteristics of Surface Area, Average Diameter, and Tips 53 Table 5.1 EC 50 (%) and Cyanide Concentration of Leachate 74 Table 5.2 EC 50 (%) of Soil Samples 75 Table 5.3 Overall Mass Balance of Cyanide after 4 Months (%) 76 Table 6.1 Acid Extractable Aluminum, Calcium, Iron, Magnesium, and Manganese 95 Table 6.2 Freudlich Isotherm Parameters as a Function of Sorbents 96 Table 7.1 Freundlich Adsorption Isotherm Parameters 114 [...]... result of surface runoff and movement through soil into potable groundwater Soil contaminated with cyanide compounds may result from a variety of industrial and municipal activities Sodium ferrocyanide [Na4FeII(CN)6)] and potassium ferrocyanide [K4FeII(CN)6)] are used in road salts as anti-clumping agents gold mining ores Alkaline cyanide solutions are used in heap leaching of Soils contaminated with cyanide. .. transport of these compounds poses a serious risk of groundwater contamination Prediction of fate of these contaminants is often complicated by their physical characteristics and complex interactions in soil and groundwater The sorption and solubility characteristics of cyanide complexes play a major role in controlling contaminant fate and transport in the subsurface The chemistry of cyanide in soils... WAD cyanide, other toxicologically important forms of cyanide are free cyanide, sodium cyanide (NaCN), potassium cyanide (KCN), and moderately and weakly complexed metal-cyanides Weak complexes include tetracyanozincate [Zn (CN)42-] and tetracyanocadminate [Cd(CN)42-], while the strong complexes contain iron cyanide complexes, which are ferro- and ferricyanide complexes ([Fe(CN)64-], [Fe(CN)63-]), and. .. is well documented The seeds of Linum usitassimum predominately contain two cyanogenic diglucosides, linustatin and neolinustatin, which disappear following germination and subsequent plant growth (Niedzwidez-Siegien, 1998) The cyanogenic monoglucosides, linamarin and lotaustralin, predominate in the leaves, stems, and roots of growing and mature plants (Conn, 1980a; Fan and Conn, 1985; Frehner et al.,... However, iron cyanide complexes cannot be regarded as completely inert (Meeussen et al., 1994), because iron cyanide complexes are easily decomposed to HCN 2.4 Solubility of Iron Cyanide Complexes Iron cyanide complexes are the predominant form of cyanide compounds at MGP sites, specifically Prussian blue decompose to free cyanide These cyanide complexes are not stable and tend to Thermodynamically, free cyanide. .. subdivided into weak acid dissociable and strong complexes, as shown in Table 2.2 This classification includes free and strong metal complexed cyanides aq)) Free cyanides, hydrogen cyanide (HCN (g, and cyanide ion (CN-(aq)), are defined as the forms of molecular and ionic cyanide released into solution by the dissolution and dissociation of cyanide compounds and complexes (Smith et al., 1991) In addition... of Fecyanide complexes to free cyanide species is favored by acidic pH and high redox conditions Meeussen et al (1992) stated the following regarding the stability of non-toxic iron- cyanide complexes in soil and groundwater Iron cyanide complexes are 10 thermodynamically stable only under conditions which may be considered as rather extreme for soils and the environment, a relatively high pH combined... concentration of iron cyanide complexes in soil solutions may be governed by Prussian blue which has lower solubility and higher sorption capacity below pH 5 Adsorption experiments for iron cyanide complexes are summarized in Table 2.5 Sorption of iron- cyanide complexes onto soil surfaces is the main immobilizing process at low concentrations (Meeussen, 1992) Although the soil has limited sorption of iron cyanide. .. sorption of iron cyanide complexes, with ferricyanide sorption decreasing with increasing ionic strength In contrast, ferrocyanide sorption is only slightly influenced by ionic strength Organic matter and the presence of clay minerals have been shown to promote the sorption of iron cyanide complexes (Fuller, 1985; Rennert, 2002) 2.6 Microbial Degradation of Cyanide Microbial degradation of cyanide (Castric,... reducing contaminant mobility and preventing migration to groundwater The extraction and accumulation of contaminants in harvestable plant tissues including shoots and leaves (phytoextraction), degradation of complex organic molecules into simple molecules and the incorporation of these molecules into plant tissues (phytodegradation), and stimulation of microbial and fungal degradation by releasing . August, 2006. Phytoremediation of Iron Cyanide Complexes in Soil and Groundwater. Major Professor: M. Katherine Banks. High concentrations of cyanide in soil can result from contamination by road. Information and Learning Company. i PHYTOREMEDIATION OF IRON CYANIDE COMPLEXES IN SOIL AND GROUNDWATER A Dissertation Submitted to the Faculty of Purdue University by Dong-Hee Kang In. ferrocyanide [K 4 Fe II (CN) 6 )] are used in road salts as anti-clumping agents. Alkaline cyanide solutions are used in heap leaching of gold mining ores. Soils contaminated with cyanide complexes