Environmental Surfaces and Interfaces from the Nanoscale to the Global Scale

Preface xv Constants and Units xvii Periodic Table of the Elements 1 Some Fundamental Chemical Thermodynamic and Kinetic Concepts 1 Concentration Units 1 Thermodyamic Versus Kinetic Approaches 2 Introductory Thermodynamics 3 Gibbs Energy 4 Chemical Potential and Activity 4 Equilibrium Constants 5 Calculating the Equilibrium Constant from Gibbs Energy Changes 6 Temperature Effects on Keq 8 Calculating Activities 9 Saturation Indices (SIs) 12 Carbonate Equilibria in Open or Closed Systems 13 Calcite Equilibria in a System Open to Atmospheric Carbon Dioxide 14 Redox Reactions 17 Metal Speciation Diagrams 19 A Brief Introduction to Kinetics 20 Overall Versus Elementary Reactions 20 Molecularity and Reaction Order 21 Transition State Theory and the Arrhenius Equation 24 Michaelis-Menten Kinetics 25 The Elovich Equation for Chemisorption Kinetics 26 Simultaneous Versus Sequential Reaction Sequences 27 Transport Versus Surface Control of Mineral Growth and Dissolution Rates 28 Rate Laws for Surface-Controlled Mineral Growth and Dissolution 30 Equilibration Time in Porous Media 31 Questions for Further Thought 31 Further Reading 34 2 The Hydrologic Cycle as Context for Environmental Surfaces and Interfaces 35 The Structure and Fundamental Properties of Water 35 The Chemical Composition of the Earth 37 The Critical Zone 38 The Hydrologic Cycle 38 Oceans 39 Atmosphere 40 Underground water 43 Soils and Soil Water 44 Groundwater 45 Surface Waters: Focus on Rivers 52 Stream Load 52 Gibbs Plots 54 The Hyporheic Zone 56 The OTIS Model and Solute Transport in Streams 56 Particle Transport and Sedimentation 57 Water Budgets and Chemical Fluxes in Terrestrial Ecosystems 59 Questions for Further Thought 62 Further Reading 66 3 Some Minerals of Special Interest to Environmental Surface Chemistry 67 Gibbsite 67 Quartz 68 Kaolinite 69 Smectite: Example Montmorillonite 71 Fe(hydr)oxides 73 Hematite 73 Goethite 73 Lepidocrocite 76 Maghemite 77 Ferrihydrite 77 Magnetite 77 Manganese Oxides 77 Calcite 78 Feldspars 79 Zeolites 79 Questions for Further Thought 81 Further Reading 81 4 Some Key Techniques for Investigating Surfaces and Interfaces 82 A Brief Overview of Some Commonly Used Techniques 82 In-Depth Descriptions of Some Key Techniques 86 Scanning Electron Microscopy (SEM) 86 Transmission Electron Microscopy (TEM) 87 Scanning Tunneling Microscopy (STM) 90 Case Study: Imaging Parameters and High-Resolution Imaging of Hematite 91 AFM and Interfacial Forces 92 X-Ray Photoelectron Spectroscopy (XPS) 99 BET Surface Area Measurements 100 Some Synchrotron-Based Techniques 103 Microscopies for Biofilm Imaging 108 Questions for Further Thought 108 Further Reading 111 5 Surfaces and Interfaces 112 What is a Surface? What is an Interface? 112 The Challenges of Defining Surfaces and Interfaces 113 Surfaces are Complex 114 Relaxation and Reconstruction 114 Surface Sites 115 Surface Microtopography 116 Surface Free Energy 117 Water Near Surfaces 119 Dynamic Surfaces 120 Bacterial Substrates 120 Fractal Properties of Surfaces and Environmental Particles 120 Interdisciplinary Topic of Study 123 Surface Free Energy and Surface Excess 124 Surface Tension and Related Phenomena 126 Surfactants and Micelles 126 Contact Angle 127 The Young-Laplace Equation 128 Meniscus and Capillarity 128 The Gibbs Equation 130 Some Approaches to Surface and Interface Modeling 130 Case Study: Bacteria–Mineral–Gas Interactions in the Vadose Zone 132 Questions for Further Thought 133 Further Reading 135 6 The Charged Interface and Surface Complexation 136 Some Evidence for Surface Charge 136 Sources of Mineral Surface Charge 137 Points of Zero Charge 139 Case Study: The Surface Charge Properties of Kaolinitic Soils 140 Sorption Terminology 141 Cation Exchange Capacity 145 Sorption Isotherms 148 Adsorption Isotherm Equations 151 The Langmuir Isotherm Equation 151 The Freundlich Isotherm Equation 152 The Frumkin Isotherm Equation 153 The Double Layer, Gouy-Chapman Theory 153 Beyond Gouy-Chapman: Surface Complexation Models 155 Constant Capacitance Model (CCM) 161 The Diffuse Double Layer (DDL) Model 161 Triple Layer Model (TLM) 161 Charge Distribution CD/MUSIC Model 162 Model Verification and Validation 163 Case Study: Incorporating the Work Associated with Removal of Water During Adsorption into the TLM 164 DLVO Theory and Colloid Attachment in Porous Media 165 Questions for Further Thought 168 Further Reading 172 7 Sorption: Inorganic Cations and Anions 173 A Typical Sorption Experiment Design 174 Metal Cation Sorption 176 The Complexity of Cation Adsorption 179 Inorganic Anion Adsorption 183 Phosphate Adsorption 184 Nitrate Adsorption 186 Sulfate Adsorption 186 Carbonate Sorption 186 Importance of Redox State and Valence to Inorganic Ion Adsorption 187 Chromium 187 Neptunium 188 Uranium 188 Selenium 188 Case Study: Arsenic Speciation and Mobility 189 Questions for Further Thought 192 Further Reading 193 8 Sorption: Organic Compounds 194 A Brief Introduction to Organic Chemistry 195 Some Organic Compounds of Interest in Environmental Surface Chemistry 200 Polymers 200 Organic Surfactants, Including Fatty Acids 200 Humic Substances 201 Polycyclic Aromatic Hydrocarbons (PAHs) 202 Substituted Nitrobenzenes (SNBs) 204 Volatile Organic Compounds (VOCs) 205 Sorption of Simple Organic Ligands, Surfactants, and Natural Organic Matter 205 Adsorption of Simple Organic Ligands 205 Adsorption of Anionic Surfactants, Fatty Acids 207 Sorption of Cationic Surfactants 208 Sorption of Phospholipid Surfactants: Biomedical Implications 209 Adsorption of Humic And Fulvic Acids (NOM) 210 Metal–Ligand Coadsorption: Ternary Surface Complexes 214 Sorption of Some Organic Pollutants 215 Vapor Pressure, Solubility, and Density 215 The Octanol-Water Partition Constant, Kow 218 Organic Fuel and Solvent Leaks: Volatilization, Solubility, Density, and Kow 219 The Hammett Constant σ for Substituted Aromatic Acids Based on the Benzene Ring 220 Case Study: Sorption of SNBs 221 Molecular Dynamics (MD) Modeling of Atrazine Absorption 223 The K d Approach to Hydrophobic Organic Compound Transport in Porous Media 224 Activated Carbon and Sorption of VOCs 226 Questions for Further Thought 227 Further Reading 230 9 Mineral Nucleation and Growth 231 Saturation State and Mineral Nucleation: An Example of the Confluence of Thermodynamics and Kinetics 231 Hydroxypyromorphite Nucleation 233 Heterogeneous Nucleation and Epitaxial Growth 233 From Nucleation to Growth 236 Ostwald Ripening 236 Transport and Surface Controlled Growth 236 The Special Importance of Kink Sites 237 BCF Theory 238 Growth Mode and Driving Force 240 Case Study: Calcite Birth and Spread versus Spiral Growth: BCF Theory 241 Rates of Step Advancement 242 Impurities and Growth at Steps 245 Monte Carlo Simulations of Crystal Growth 246 Biomineralization 247 Carbonate Precipitation in the Marine Environment 249 Questions for Further Thought 251 Further Reading 252 10 Mineral Weathering and Dissolution 253 Chemical, Physical, and Biological Weathering 253 Thermodynamics of Mineral Weathering 256 Kinetics of Mineral Dissolution 260 Etch Pit Formation 261 Oxalate Promoted Dissolution of Hematite 263 Comparison of Laboratory- and Field-Based Dissolution Rates 264 Reactive Surface Area and Feldspar Dissolution 266 Rainfall and Weathering: An Example from the Hawaiian Islands 269 Case Study: Weathering in the Antarctic Dry Valleys 270 Reactors for Dissolution Experiments 273 The Use of Radiogenic Isotopes in Weathering Studies 276 Questions for Further Thought 276 Further Reading 279 11 Plants as Environmental Surfaces 280 Ecohydrology and Soil Moisture Balance 280 Some Notes on Angiosperm Physiology 282 The Nutrient Needs of Plants 282 Effects of Plants on Mineral Dissolution and Weathering 284 Modes of Plant Elemental Cycling 287 Plants and Biomineralization: Phytoliths 287 Plants and Formations in Limestone Caves 289 Phytoremediation as an Example of Plant-Mineral-Contaminant Interactions 291 Case Study: Phytoremediation of Atrazine 293 Questions for Further Thought 294 Further Reading 295 12 Microorganisms As Environmental Surfaces 296 How Microorganisms “make a Living” 298 Metabolic Pathways 298 Microbial Redox Reactions and Michaelis-Menten Kinetics 303 Microbial Temperature Ranges and Extremophiles 305 Microbial Growth Curves 306 Bacterial Groups 307 Bacterial Cell Walls 307 Bacterial Adhesion and Biofilms 309 Bacterial–Metal Interactions 312 Bacterial-Promoted Mineral Dissolution 313 Dissolution of Fe(III)(hydr)oxides by DIRB 313 Dissimilatory Metal-Reducing Bacteria 315 Microbial Effects on Carbonate Dissolution 315 The Importance of Field-Based Studies 317 Case Study: The In Situ Microcosm Approach 318 Coupling In Situ Microcosms with Community Analysis 318 Siderophores 320 Microbial Biomineralization 322 Carbonate Precipitation 322 Fe(III)(hydr)oxide Precipitaton: BIOS 323 Banded Iron Formations (BIF) 324 (Alumino)silicate Precipitation 326 Case Study: Bioremediation of U at the Oak Ridge National Laboratory Site 327 Microbial Fuel Cells 329 Questions for Further Thought 332 Further Reading 333 13 Environmental Nanoscience and Nanotechnology 335 What is a Nanoparticle? 335 Nanoparticle Occurrence and Distribution 337 What Makes a Nanoparticle Different? 339 Nanoparticle Surface Area, Stability, and Reactivity 340 Nanoparticles Have a Different Electronic Structure 340 How Electronic Structure Influences Nanoparticle Behavior 342 Nanoparticle Disorder and Defect Structures 343 Ferrihydrite Size, Structure, and Stability 343 Effects of pH and Adsorbed Ions on Nanoparticle Stabilities 344 Case Study: Fe(hydr)oxide Size and Stability 345 Secondary Growth of Nanoparticles 346 Self-Assembly and Templating 348 Nanoparticle Transport in Porous Media 348 The Emergence of Nanotechnology 350 Potential Environmental Effects of Engineered Nanoparticles 351 Questions for Further Thought 353 Further Reading 354 14 The Big Picture: Interface Processes and the Environment 356 Reactive Transport Models for Metals and Radionuclides in Porous Media 356 The K d Approach Encounters Difficulties for Metals and Radionuclides 356 Comparison of the K d versus Surface Complexation Modeling Approaches 357 Acid Rain Effects on Chemical Weathering 358 What Makes Rainfall Acidic? 359 Effects of Acid Rain 360 Acid Rain and Chemical Weathering 360 The Small Watershed Approach 362 NETPATH and PHREEQC 362 The Clean Air Act and Acid Rain Over Time 363 Acid Mine Drainage 364 The Environmental Problem 365 Nanoparticles and AMD 365 Hydrobiogeochemical and Photoreductive Processes 365 Biofilms and AMD 367 Potential Remediation Strategies 369 Environmental Particles and Climate Change 369 Climate Forcing and Feedbacks 370 Volcanoes and Climate 373 CO2 and Weathering 374 Modeling the C Cycle Over Geologic Time 376 Scaling Phenomena: Integrating Observations from the Atomic to the Watershed to the Global Scale 378 The Concept of the Macroscope 378 Embedded Sensor Network Systems 379 Sensors for Surface and Interface Phenomena 380 New Opportunities: New Challenges 380 Questions for Further Thought 381 Further Readings 383 Glossary of Terms 385 References 405 Index 437