PowerPoint PresentationU6220: Environmental Chem. & Tox.Slide 3Slide 4Slide 5Slide 6Slide 7Slide 8Slide 9Slide 10Slide 11Slide 12Chemical Elements (the Periodic Table) and those essential for lifeSlide 14Slide 15Slide 16Slide 17Slide 18Slide 19Slide 20Slide 21Slide 22Slide 23Slide 24Slide 25Slide 26Slide 27Slide 28Slide 29Slide 30Slide 31Slide 32Slide 33Slide 34Slide 35Slide 36Slide 37Slide 38Slide 39Slide 40Slide 41Slide 42Slide 43Slide 44Slide 45Slide 46Slide 47Slide 48Slide 49Slide 50“Creative minds have been known to survive any sort of bad training. - Anna Freud“Your theory is crazy, but it's not crazy enough to be true.” Niels Bohr“Never express yourself more clearly than you are able to think” Niels BohrA)A) Intro to Fate & Transport of Environmental Intro to Fate & Transport of Environmental contaminants contaminants B)B)Basic Chemistry reviewBasic Chemistry reviewC)C)Chemical processes: Sorption and Chemical processes: Sorption and particulate transportparticulate transportU6220: Environmental Chem. & Tox.Chemical cycling and role of the “anthroposphere” (or Chemical cycling and role of the “anthroposphere” (or “anthrosphere”)“anthrosphere”)Introduction to Environmental ChemistryIntroduction to Environmental Chemistry- AquaticAquatic: Water as solvent (polar): Water as solvent (polar)Mobility, solubility, exchange with other phases Mobility, solubility, exchange with other phases (sorption, precipitation, volatilization, condensation)(sorption, precipitation, volatilization, condensation)- AtmosphereAtmosphere: No chemical bonds between individual : No chemical bonds between individual components in gas phasecomponents in gas phasePartial pressure, exchange (precipitation, volatilization), Partial pressure, exchange (precipitation, volatilization), mobilitymobility SolidsSolids: less mobile phase  sequestration (low : less mobile phase  sequestration (low bioavailability - really? Children…)bioavailability - really? Children…)Interaction with other phases (sorption, dissolution, etc)Interaction with other phases (sorption, dissolution, etc)MediaMediaSource and Fate of Chemicals in the Source and Fate of Chemicals in the EnvironmentEnvironmentChemical fate in a defined “controlled” volume Chemical fate in a defined “controlled” volume (boundary conditions)(boundary conditions)•Chemical reactions - speciationChemical reactions - speciation•Biological uptake - Bioaccumulation - Transformation - Biological uptake - Bioaccumulation - Transformation - ExcretionExcretion•Physical processes (mobility- diffusion/advection - Physical processes (mobility- diffusion/advection - immobilization)immobilization)Source and Fate of Chemicals in the Source and Fate of Chemicals in the EnvironmentEnvironmentPhysical transportPhysical transport•Advective transportAdvective transport•(Diffusive transport)(Diffusive transport)Units of interest are units Units of interest are units of mass (or moles) per of mass (or moles) per area/volume, per unit area/volume, per unit time:time:Flux (J, Q, etc)Flux (J, Q, etc)Atmospheric TransportAtmospheric TransportA knowledge of physical transport and chemical reaction rates is needed to A knowledge of physical transport and chemical reaction rates is needed to predict concentrations of air pollutants as they are transported away from predict concentrations of air pollutants as they are transported away from their source (also applicable to water transport)their source (also applicable to water transport)Advective motion of fluids (gases, liquids) will disperse a contaminant in the Advective motion of fluids (gases, liquids) will disperse a contaminant in the direction of the fluid motion (direction of the fluid motion (flux densityflux density):):J = CVJ = CVTurbulent and molecular diffusion processes will carry contaminant mass in Turbulent and molecular diffusion processes will carry contaminant mass in the direction of decreasing chemical concentration (spreading)the direction of decreasing chemical concentration (spreading)J = -D(dC/dx)J = -D(dC/dx)Surface Water TransportSurface Water TransportA knowledge of physical transport and chemical reaction rates is needed to A knowledge of physical transport and chemical reaction rates is needed to predict concentrations of water pollutants as they are transported away predict concentrations of water pollutants as they are transported away from their source (remember atmospheric transport)from their source (remember atmospheric transport)Advective motion of fluids (gases, liquids) will disperse a contaminant in the Advective motion of fluids (gases, liquids) will disperse a contaminant in the direction of the fluid motion (direction of the fluid motion (flux densityflux density):):J = Q.C (or in generally C.V)J = Q.C (or in generally C.V)Turbulent and molecular diffusion processes will also carry contaminant Turbulent and molecular diffusion processes will also carry contaminant mass in the direction of decreasing chemical concentration (spreading).mass in the direction of decreasing chemical concentration (spreading).(source: Dr. P. Schlosser and Tracer Group (Earth & Environmental Engineering)€ C x,t( )=M4πDLte−(x−Vt )2/(4 DLt )Surface Water TransportSurface Water TransportHudson conservative tracer Hudson conservative tracer pulse injectionpulse injection experiments experimentshttp://www.seas.columbia.edu/earth/tracer/ (source: Dr. P. Schlosser and Tracer Group (Earth & Environmental Engineering)QuickTime™ and aTIFF (Uncompressed) decompressorare needed to see this picture.QuickTime™ and aTIFF (Uncompressed) decompressorare needed to see this picture.Multidisciplinary by natureEnvironmental ChemistryEnvironmental Chemistry012340 0.5 1 1.5 2 2.5 3Time (t)Conc [A]- Equilibrium: “Steady State” ConditionsEquilibrium: “Steady State” ConditionsWhere will the system end-up?Where will the system end-up?Chemical ProcessesChemical ProcessesSteady StateAt t = xAt tx = 1 sec  Fast reaction and system isAt tx = 1 sec  Fast reaction and system is““equilibrium controlledequilibrium controlled””- In practical engineering purposes  when system is In practical engineering purposes  when system is notnot in equilibrium, then the in equilibrium, then the raterate of reaction is important of reaction is important““kinetics controlledkinetics controlled””Chemical ProcessesChemical Processes0123450 50 100 150