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93101_7EnvChBasicsCondensedLect.pdf Narrative for a Lecture on Environmental Chemistry Slide 1: Environmental chemistry is that branch of chemical science tha t deals with the production, transport, reactions, effects, and fates of chemical species in the water, air, ter restrial, and biological environment and the effects of human activities thereon.ENVIRONMENTAL CHEMISTRY Environmental chemistry is that branch of chemical science that deals with the production, transport, reactions, effects, and fates of chemical species in the water, air, terrestrial, and biological environments and the effects of human activities thereon.

Reference: Stanley E. Manahan,

Fundamentals of Environmental

Chemistry,

3rd ed., Taylor & Francis/CRC Press, 2009

(manahans@missouri.edu) For additional information about environmental chemistry and to download this and other presentations see: http://sites.google.com/site/manahan1937/Home http://manahans1.googlepages.com/

S(coal) + O2 SO2SO2SO2 + 1/2O2 + H2O

H2SO4H2SO4 H 2 SO 4 , sulfatesILLUSTRATION OF THE DEFINITION

OF ENVIRONMENTAL CHEMISTRYSlide 2: The definition of environmental chemistry is illustrated with a typical pollutant species. I

n this case sulfur

in coal is oxidized to sulfur dioxide gas that is emitted to the atmosphere. The sulfur dioxide gas can be oxidizedto sulfuric acid by atmospheric chemical processes, fall back to Earth as acid rain, affect a receptor such as plants,and end up in a "sink" such as a body of water or soil.

Slide 3: In the past many environmental problems were caused by practices that now seem to be totally unacceptable as expressed from the quote in this slide from what was regarded as a reputable book on the American chemical industry in 1954.

The result was

polluted air, polluted water, dangerous hazardous waste sites, and harm to living organisms.

Into theriverOut the door

Up the stack

(From American Chemical Industry

Ña History, W. Haynes,

Van Nostrand Publishers, 1954)

The Old Attitude: ÒBy sensible definition any by-product ofa chemical operation for which there is no profitable use is awaste. The most convenient, least expensive way of disposingof said wasteÑup the chimney or down the riverÑis best.Ó

Slide 4: Dating from around 1970, laws and regulations were implemented to contro l air and water pollution and to clean up hazardous waste sites. These measure s have relied largely upon "end of pipe" controls in which pollutants were gener ated but were removed before release to the environment. Although costly and requiring constan t vigilance to make sure that standards have been met, these measures have been successful in reducing pollution and preventing increases in pollutant releases.

Currently: A Òcommand-and-controlÓ approach using Òend-of-pipeÓ treatment measures and remediation of waste siteshas reduced major environmental problems

Wastewatertreatment

Remediation

Stack controls

Slide 5: As an alternative to the regulatory approach, the tendency now is toward sustainability with systems that emphasize recycling of materials, excha nge of materials between concerns, and zero discharge of wastes. Properly designed, such systems are inherently friendly to the environment and reduce the need for measures that emphasize purely pollution control.

Now the goal must be to close the loop, recycle asmuch as possible, avoid discharge of pollutants orwastes, and apply the principles of industrial ecology,green chemistry, and green engineering

Material exchange

Zero discharge

Recycle

Slide 6: Traditionally, environmental science has considered four environmental spheres: water, air, living organisms, and earth. But it is important t o consider a fifth environmental sphere, the anthrosphere, which consists of the things tha t humans make and do. The remainder of this lecture considers environmental chemistry within a framework of these five environmental spheres.

Atmosphere

Hydrosphere

Biosphere

Geosphere

Anthrosphere

Slide 7: A variety of chemical and biochemical phenomena occur in the hydrosphere . Some of these are shown in this slide for a body of water stratified wit h a warmer oxygenated upper layer floating on top of a cooler oxygen-deficient lower layer, a common phenomenon during summer months. Gases are exchanged with the atm osphere at the surface and solutes are exchanged between water and sediment. Pho tosynthesis produces biomass, represented here as [CH 2

O]. In the oxygen

- deficient lower layer biomass undergoes biodegradation by the action of anoxic bacteria using oxidizing agents other than O 2 . When sulfate functions as the oxidizing agent odorous hydrogen sulfide gas may be evolved. 2HCO 3 + h !Photosynthesis {CH 2

O} + O

2 (g) + CO 32
- CO 3 + H 2

OAcid-base

HCO 3 + OH--

Ca + CO

3 CaCO 3 (s)Precipitation 2{CH 2

O} + SO

4 + 2H +

Microbial

action H 2 S( g) + 2H 2 O + 2CO 2 (g)

Uptake

Leaching

Ground-

waterCd 2+ C h e latio n NH +4

Reduction Oxidation

NO 3 CO 2 O 2

Gas exchange with the atmosphere

2- 2+2- 2-

Sediment

- CHEMICAL AND BIOCHEMICAL PHENOMENAIN A STRATIFIED BODY OF WATER Slide 8: An important aspect of water chemistry is water treatment. This slide sh ows the activated sludge process used to treat municipal wastewater. A suspensi on of microorganisms in an aerated tank biodegrades organic wastes represented as [CH 2 O]. This removes oxygen demand from the water so that it will not deplete ox ygen when discharged to a stream or body of water. The microorganisms settle in a settling basin and are pumped back to the aeration tank, greatly speeding the biodegradation process. Excess microorganisms, sewage sludge or biosolids also represented as {C H 2

O}, are

taken to an anaerobic digester where they produce combustible methane, C H 4 , and carbon dioxide. The methane may provide fuel sufficient to run the engines that produce all the power needed by the plant.

ACTIVATED SLUDGE WASTEWATER TREATMENT

AirSludge

settling

Purified water

with reducedBOD

Wastewater containingBOD, {CH

2 O}

Aeration tank

Settled sludge with viable microorganisms

Excess sludge toanaerobic digester

Byproduct methane

fuel gas {CH 2

O} + O

2 ! CO 2 + H 2

O + Biomass

Organic N

! NH 4 + , NO 3 -

Organic P ! H

2 PO 4 -, HPO 4 2-

Organic S

! SO 42
- 2{CH 2 O} ! CH 4 + CO 2

Anaerobic digester

Slide 9: As water supplies become more limited around the world, renovation and r e-use of wastewater become more important. This slide shows a system for purif ying wastewater treated by the activated sludge process so that it can be used for applications such as groundwater recharge and irrigation. Advanced treatment processe s can even bring the wastewater up to drinking water standards. A feature of the system shown is a wetlands area where algae and plants growing profusely in the fertile wastewater remove excess nutrients and produce biomass that can be converted to biofuels.

The largest

purification and water reuse project of its kind worldwide, the Orange C ounty California Groundwater Replenishment System, utilizes a three-step process of microfiltration, reverse osmosis and ultraviolet light to purify highly-treated sewer water to state and federal drinking water standards (http://www.gwrsystem.com/).

Secondary wastewatertreatment effluent

Wetlands

Plants and algae harvestedfor energy production

Water purified

in wetlands

Groundwater recharge

Non-potable use, irrigation

Membrane filtration, mayinclude reverse osmosis

Retentate with impurities

not passed through membraneto disposal, treatmentPotable water tomunicipal water system

Activated carbon filtration

for organics removal

Water vapor from

the hydrosphereWater (rainfall) tothe hydrosphereand geosphereThinning air

Gases and particles

from the geosphereGases and particlesfrom the anthrosphereN2, O2, argon, raw material gasesto the anthrosphere

Exchange of O

2 and CO 2 with the biosphere, release of H 2

O from plantsTemperature stabilization

(greenhouse effect)protection from ultraviolet radiation

Chemical and photochemical

processesTemperatureinversionsHigh-altitude ozone, O3,Slide 10: The atmosphere is essential for life on Earth as a source of

oxygen for organisms, carbon dioxide for plants, stabilization of surface temperatures (the good greenhouse effect), and protection from damaging ultraviolet radiation from ozone (O 3 ) in the stratosphere. Although the atmosphere extends far above Earthí s surface, over 99% of it is within a few kilometers of the surface. In fa ct, if Earth were a classroom globe, virtually all of the atmosphereís air would be in a layer the thickne ss of the varnish on the globe! A distinctive feature of atmospheric chemistry is the ability of energetic photons of ultraviolet radiation (hînuî) to put large amounts of energy into a single molecule as shown here for the photodiss ociation of stratospheric O 2 leading to ozone formation. Slide 11: Atmospheric chemistry is complex involving literally hundreds of reactio ns. Photochemical reactions occur when photons of ultraviolet radiation spli t molecules apart producing reactive fragments with unpaired electrons (represented as do ts in the slide) known as free radicals. These species undergo chain reactions such as th ose responsible for the ozone, organic oxidants, aldehydes, and solids characteristic of the unpleasant ingredients of photochemical smog that afflicts Los Angeles, Mexico City, and other urban areas around the world. Reactions such as the formation of sulfuri c acid from sulfur dioxide may occur inside water droplets and on the surfaces of pa rticles suspended in the atmosphere. !"#$%&'()*+,+'(#*%")-, Slide 12: There are many different kinds of air pollutants. Particles obscure visibility and can be detrimental to respiration. Primary particles are those that ente r the atmosphere as particles whereas secondary particles are produced by reactions of gases in the atmosphere. Several inorganic gases, mostly oxides of nitrogen, sulfur, and carbon are air pollutants. Photochemical smog results when nitrogen oxides and hydrocar bons in stagnant air masses subjected to solar radiation undergo photochemical r eactions to form ozone, organic oxidants such as peroxyacetyl nitrate (PAN), ozone, aldehydes, and other species that tend to be detrimental to visibility, respiratory systems, and eyes.

AIR POLLUTANTS

Primary Particles

¥ Pollen ¥ Dust ¥ Fly ash ¥ Polycyclic aromatic hydrocarb ons

Secondary Particles (formed from gas reactions)

¥ Smog particles ¥ Sulfuric acid droplets ¥ Salts such as ( NH 4 ) 2 SO 4

Inorganic Gases

¥ O

3

¥ SO

2 ¥ NO ¥ NO 2 ¥ CO ¥ H 2

S ¥ HCl ¥ NH

3

Organics

¥ Hydrocarbons including those that form photochemical smog ¥ Odorous organic sulfur compounds ¥ Organohalides

¥ Amines and other organonitrogen compounds

¥

Organo

-oxygen compounds including aldehydes and ketones

Photochemical Smog

¥ Smog particles ¥ Ozone ¥ Organic oxidants (PAN)

¥ Aldehydes

315320325330335340345350

1960197019801990

Year360370

2000CO2 level, ppm by volume20052010380385

380390

2010LEVELS OF ATMOSPHERIC

CARBON DIOXIDESlide 13: Although it is a normal constituent of the atmosphere essential to supp ly the carbon required for plant photosynthesis, carbon dioxide may turn out to be a harmful air pollutan t at higher levels. This is because of its role in re-absorbing the infrared radiation by which Earth radiates back into space the solar energy received from the sun. This greenhouse effect is essential to life on Earth because it keeps th e surface warm enough for living organisms to thrive. However, if too much carbon dioxide is present in the atmosphere , Earth"s surface will become too warm—the bad greenhouse effect—leading to melting of polar ice caps and glacie rs, elevated sea levels, severe droughts, and other detrimental effects. As shown in the plot, on this slide, atmospheric ca rbon dioxide levels from the burning of fossil fuels and other sources have been increasing by about 1 part per million per year, now closer to 2 parts per million per year. The resulting doubling of atmospheric carbon dioxide levels wi thin the next century could have substantial, perhaps catastrophic, effects upon the global climate. Slide 14: The geosphere has a very close relationship with the hydrosphere, the atmosphere, and the biosphere and is strongly affected by human activiti es in the anthrosphere. On Earth's surface, the geosphere is composed of rocks in turn made of var ious minerals and usually a thin layer of soil. Igneous rocks thrust upw ard by tectonic forces are broken down (weathered) by physical, chemical, and biologic al processes and material from them is deposited as sedimentary rock. Heat and pressure c onvert se dimentary rock to metamorphic rock.

Igneousrock

Sedimentaryrock

Metamorphicrock

Heat, pressure

Upwelling, solidifying magma

Hot, molten magmaWeathering, erosion

Transport, sedimentation

Slide 15: Geochemistry is the chemistry of rocks and minerals in the geosphere as it relates to the hydrosphere, atmosphere, biosphere, and, very recently in the geological timetable, the anthrosphere. The geochemical reaction shown in the slide is important in putting dissolved calcium and bicarbonate ion (water alkalinity) into water. The dissolution of calcium carbonate (limestone) by this process causes th e formation of caves and cavities in limestone rock formations. Environmental geochemistry is the environmental branch of geochemistry and is important in considering the effects and fates of pollutants in the geosphere.

GEOCHEMISTRY

Geochemistry

!"#$%&!'()*!+*#,(+$%!&-#+(#&.!/#$+012&.!$2"!-/1+#&&#&!(2!)*#!

3#1&-*#/#!$2"!)*#(/!(2)#/$+012&!'()*!)*#!$),1&-*#/#!$2"!*4"/1&-*#/#5!

For example, carbon dioxide from the atmosphere dissolves in water in the hydrosphere, then reacts with limestone in the geosphere:

¥ CaCO

3 ( s ) + H 2

O + CO

2 ( aq ) ! Ca 2+ ( aq ) + 2HCO 3- ( aq )

ENVIRONMENTAL GEOCHEMISTRY

627(/12,#2)$%!3#1+*#,(&)/4!(&!)*#!8/$2+*!19!3#1+*#,(&)/4!)*$)!#:-%1/#&!)*#!

+1,-%#:!(2)#/$+012&!$,123!)*#!/1+;<'$)#/<$(/<%(9#!&4&)#,&!)*$)!"#)#/,(2#!)*#! +*#,(+$%!+*$/$+)#/(&0+&!19!)*#!&=/9$+#!#27(/12,#2)5 Slide 16: The geosphere is a crucial source of natural capital including essential metals, fuels, and plant nutrients. The geosphere is an important repository of wastes. One such waste for which the geosphere is likely to become a very important repos itory in the future is carbon dioxide from fossil fuel combustion that is currently released to the atmosphere where it causes global warming.

THE GEOSPHERE AS A SOURCE OF NATURAL CAPITAL

Natural capital is a term that describes the resources or value of the environment such as in providing essential materials or absorbing wastes The geosphere is a crucial source of natural capital

¥ Fuels, such as natural gas

¥ Metals, such as iron or copper

¥ Nonmetals, such as clay, sand, gravel

¥ Plant nutrients, such as phosphorus

¥ Absorption of wastes, such as carbon dioxide from fuel combustion pumped underground (carbon sequestration) The most important aspect of natural capital in the geosphere is the ability of soil to support plant growth for food production (next slide ) Slide 17: Soil is a crucial component of natural capital because all terrestrial o rganisms including humans depend upon it for their existence. The layer of produc tive soil on E arth's surface is extremely thin and subject to damage and erosion. M uch productive soil has been lost or ruined and soil conservation is a top priority for sustainability.

SOIL: THE MOST IMPORTANT GEOSPHERIC RESOURCE

Soil is obviously of crucial importance as a support for plant growth Soil is composed of finely divided, highly weathered mineral matter and organic matter from the partial biodegradation of plant material EarthÕs soil is a very thin layer; if Earth were a classroom globe, the average thickness of the total soil resource would be about the same as the diameter of a human cell! Soil is divided into layers called soil horizons (next slide) Slide 18: Soil is typically divided into layers called horizons. Many important chemical and biochemical reactions occur in soil. Soil is subject to water and w ind erosion, and one of the earliest environmental movements, dating back to around 1900 in the U.S., has been soil conservation. Large areas of formerly productive agricultural land have been turned to desert by poor agricultural and animal grazing practices, a la rge problem for sustainability.

SOIL HORIZONS

Vegetation

A horizon, topsoil, layer of root

growth, biodegradation, high organic content

E horizon, layer that is

weathered and leached, often by organic acids from the A horizon

C horizon, weathered

parent rock

Bedrock

O horizon from

decayed and decaying plant biomass

Regolith: unconsolidated

rock debris, organic matter

B horizon, or subsoil, reposi-

itory of organic matter, salts, and clay particles Slide 19: Living organisms constitute the biosphere. Through photosynthesis of pla nts and algae it is the basis of the food chain. In addition to food, the biosphere is a crucial source of biomass for raw material and, in the future, for synthetic fue l. This slide shows a heavy growth of switchgrass, a plant that is remarkably productive of biomass on poor soil and that has significant potential as a renewable fuel resource. !"#$%&'()"#*#$ (+&!,"-*.((/$.$)'!#0!&.112$&3)'*!.0!$ ('4*,#$'5$%&'3.(($ .$67898:;<67$8=$<$7>;>$

CE$97>$)8A>;)8CE9$6;>B>E9

ToxicantOrganismToxic

effect. . . . . + . . . . . ToxicologyToxicological chemistryA MAJOR CONCERN REGARDING THE

BIOSPHERE IS THE EFFECT OF TOXICSUBSTANCES ON ORGANISMS:TOXICOLOGICAL CHEMISTRYSlide 20: A major consideration with respect to the biosphere is the effect of to

xic substances on organisms. Toxicological chemistry addresses the relationship between th e chemical nature of substances and their toxic effects. Slide 21: An interesting aspect of toxicological chemistry is the wide range of to xicities of various substances. The LD 50
values shown in this slide are the doses in mg toxic substance to kg body mass estimated to kill 50% of test subjects. Diethylhexylphthalate (DEHP) is a low toxicity plasticizer added to plastics such as polyvin ylchloride to make them more flexible. Malathion, an organophosphate insecticide, is relat ively safe because mammals, but not insects, can hydrolyze the molecule to safe materials. Though an effective, highly biodegradable organophosphate insecticide, parathion i s now banned because of its toxic effects. Tetrodotoxin is the toxin of the puffer f ish. The Australian inl and taipan snake is known at a "two-step" snake; if it strikes you, you take two steps then fall down dead. TCDD is the infamous dioxin, which causes an unsigh tly chloracne skin condition in humans but is deadly to some other species such as gui nea pigs. B otulinus toxin produced by botulinus bacteria is one of the most toxic s ubstances known, but in dilute form has many medical uses and is the basis of Boto x used to remove skin wrinkles. !"#$ %& "'()*+,"(-+"./"*/.0,"12"34"12"015.6(/0"7+-"84"12"91:;"3(,,<"

If this area represents a

fatal dose of parathion,the area of the circle belowrepresents a fatal dose of SarinRELATIVE TOXICITIES OF TWO

ORGANOPHOSPHATE

COMMPOUNDS. PARATHION IS

A PESTICIDE NOW BANNED

BECAUSE OF ITS TOXICITY AND

SARIN IS A MILITARY POISON

NERVE GAS.Slide 22: Illustrating the great differences in toxicities of substances, if the big red circle represents a fatal dose of parathion organophosphate insecticide, now banned because of its toxi city if not handled properly, the little black dot represents a fatal dose of organophosphate Sarin nerve gas— quite a difference! Slide 23: The body metabolizes toxic substances to detoxify them. Benzene, once wi dely used as a solvent and reagent in organic chemistry laboratories, but now discontinued because of its potential to cause blood abnormalities and possibly leuke mia, is metabolized by cytochrome P-450 enzymes to products such as phenol and trans,trans- muconic acid that are eliminated through urine. Benzene oxepin and benze ne oxide are reactive intermediates that react with biomolecules in the body to produ ce the toxic effects of benzene.

EXAMPLE OF BENZENE

METABOLISM THAT CAUSES

BLOOD ABNORMALITIES

OH H

Benzene epoxide Benzene oxepin

OH H OH + {O}

Enzymatic

epoxidation O

PhenolNonenzymatic

rearrangement

Other metabolic products including the following:

OH OH O O

CCCCCC OHO

HO OH HH H Catechol p-benzoquinone trans,trans-muconic acid Slide 24: Benzene has been replaced in the laboratory with toluene, which has solv ent and chemical properties that are largely similar to those of benzene. Ho wever, the -CH 3 side group on toluene is readily oxidized by body enzymes to benzoic acid, a harmless, common food metabolite. Benzoic acid is conjugated with one of the body 's natural amino acids, glycine, to produce hippuric acid, which is eliminated through urine. So me older organic chemistry laboratory manuals recommend collecting urine from horses from w hich hippuric acid can be extracted. The collection procedure is at best mess y and can be hazardous because horses are notorious for objecting to donation of their body fluids or parts to science. !

BENZENE IS LARGELY REPLACED BY

TOLUENE, WHICH IS METABOLIZED TO

HARMLESS PRODUCTS

CH H H !"# CH H OH $%&'() ! *)+,-,) CO OH $%&',.+!*+./ CO NH CH H CO OH ,0./*1.,&2!3-*4%!5 6 ! 7!"#2 ! %&'(8*1.+!,0./*1.,& 3-*4% ! 55
! +,&9:;*1.,& <.1- ! ;)(+.&% !!!! =.>>:?.+ ! *+./ @ABC%&',();)(+.&%D<.1-!),44!,E!= 7 " Slide 25: The anthrosphere is the fifth environmental sphere to be considered. It consists of the many things that humans make or do, only a few of which are shown here. The anthrosphere is so important in determining conditions on Earth that in

2000 the Nobel

Prize winning atmospheric scientist Paul Crutzen made a convincing argument that we are now leaving the Holocene Epoch, which began with the latest intergla cial period about 12,000 years ago and have entered the Anthropocene Epoch in which human activities, such as emissions of massive amounts of global-warming carbon dioxide to the atmosphere, predominate in determining Earth's environment. ! Structures used formanufacturing,commerce,and otheractivities

Dwellings

Utilities, including water,fuel, and electricitydistribution systems,and waste collection systems, (sewers)Trans-portation sys-tems, including rail-roads, airports, andwaterways con-structed or mod-ified for watertransport

Food productionsystems,including culti-vated fields,irrigation systems,and animal feedlots Machines of var-ious kinds, includ-ing automobiles,farm machin-ery, and air-planes Structures and devices used for communications, such as telephone lines and radio transmitter towers Mines, oil wells, and other structures used by extractive industries

Anthro-sphere

THE ANTHROSPHERE

Slide 26: Shown here is a general outline of a manufacturing process in the anthrosphere such as might be used in the chemical industry. One aspect of manufactur ing that has caused many problems is the production and improper disposal of hazardou s waste substances including toxic heavy metals and organochlorine compounds tha t have a tendency to undergo bioaccumulation. One of the most notorious hazardous waste disposal sites in the U.S. is the Love Canal site near Niagara Falls, Ne w York, where

21,000 tons of chemical wastes containing more than 80 different compoun

ds were disposed. !

EnergyTransportationCommunication

Processingraw materialto finishedmaterial

Raw materialfrom extractivesources

Fabrication and assemblyof product

Raw materialfrom renewablesources

Finished

material

Recycling and disposal

Recycled

material

Recycled

parts

Consumer

Product distribution

Spent product

Waste Slide 27: Dating from the 1990s, green chemistry has become an important disciplin e in the practice of sustainable, environmentally safe chemical science and technology. !

Renewablefeedstocks

Product

No wasteRecycle

DegradabilityReaction

conditions,catalysts

Control

Green chemistry is the practice of chemical science andmanufacturing within a framework of industrial ecology in amanner that is sustainable, safe, and non-polluting and thatconsumes minimum amounts of materials and energy whileproducing little or no waste material.

Slide 28: Industrial ecology dating from around 1990 is very much related to green chemistry. It calls for various enterprises to practice industrial metab olism co-existing to mutual advantage in industrial ecosystems.

INDUSTRIAL ECOLOGY

Industrial ecology

!"#$%&!'(!#()*&+,#'-! &.&+$/!'&!'(!',012#'-!$23&.&+$/4!%#+5!6,#/',.! &3*,2$&!37!,'%!/'+$,#'-&!'()!$($,8.!'()!%#+5!'! (*/9$,!37!$(+$,6,#&$&!/':#(8!*&$!37!%5'+!%3*-)!

3+5$,%#&$!9$!%'&+$!6,3)*2+&!37!3+5$,!/$/9$,&!

37!+5$!&.&+$/!6,'202$)!#(!'!/'(($,!+5'+!

/#(#/#;$&!$("#,3(/$(+'-!#/6'2+!%5#-$!360/#;#(8! *0-#;'03(!37!,$&3*,2$&4!$($,8.4!'()!2'6#+'-O} using as a

reagent elemental hydrogen produced from the electrolysis of water by wi ndpower. CO 2 + H 2 O + h ! ! " {CH 2

O} + O

2

Carbon Fixation byphotosynthesis

CO 2 CO

2Combustion{CH

2

O}HydrogenationPyrolysis

H 2

Water electrolysisby wind-generatedelectricity

Biorefinery

Organics

Electricity

Brackish waterwastewater

Waterpurification

Pure water

Fixedcarbon

Lignite Electricity

Districtheatingcooling

Byproduct heatGasificationmethanesynthesis

CH 4 , main product

MunicipalcommercialElectricity

Solid wastes, wastewater

Biological treatmentincluding anoxicdigestion

Solids, CO

2 H 2 Water to purification, recycle,irrigation, algae ponds NH 3

AmmoniasynthesisH

2 N 2 NH 3 Slide 30: Sustainability must be the goal, leaving Earth in a condition to support future generations with a good quality of life. !"#$%#&''#&()*"#+*%",$-,($'$"./##01,2$-3#4,5"6# $-#,#7)-8$9)-#")#+*::)5"#;*"*51# <1-15,9)-%# Slide 31: When it comes to sustainability, energy is the key component. For a sustainable world future energy supplies must be sustainable, abundant, safe, environmentally benign, and affordable. Meeting these criteria is a huge challenge. !"!#$%&''(!%')*'+,+)-."-/.0.)%' +1234564758539':;<15:;2';6;:=9'3>43'52'
?'+123456478;' ?'-716@463' ?'+4A;' ?'!22;6B4889'>4:C8;22'3D'3>;';6E5:D6C;63' ?'-FD:@478;' Slide 32: Abundant, sustainable energy can enable accomplishment of all of the goa ls listed in this slide plus many more. !"!#$%&'()#*!'&+!!,-"$&,.!'!& *#-,!#-/&*/"& • !0123456&6768914849:& • !0123456&82;<219&<21&5=6774>?@&636>&4>&AB1@A&6>3412>;6>9@& • !+669&91B>@C219BD2>&>665@& • !E6@B74>B96&@6B=B961&92&C123456&BFG>5B>9&=B961&@GCC746@& • !#6>23B96&=B@96=B961&92&514>H4>?&=B961&@9B>5B15@& • !!>BF76&@247&16@921BD2>& • !':>9A6@4I6&BFG>5B>9&>4912?6>&<61D74I61&<21&812C@& • !E6@912:&ABIB152G@&=B@96@&21&CG9&9A6;&4>92&B&>2>ABIB152G@& <21;& • !!74;4>B96&B41&B>5&=B961&C277G9B>9@& Slide 33: There are many energy alternatives, a number of which are from renewable sources. !"#$%&'()$#*#)+,$&-!#)*&!./#0$ • !123345$67853$ • !98:;2587<$=;7>>4>?$27:@$A( B $8<43342>3C$ • !*D:7;D5$?D3$=<4>43@$4>$3E2;:$37FF5G$H7;4>?$ ;8I8>:$G8D;3@$37FF5483$EDJ8$3:D;:8H$4>I;8D34>?$6;2<$

7>I2>J8>K2>D5$327;I83$37IE$D3$K?E:$3ED583C$

• !A2D5$=DL7>HD>:@$E4?E$A( B $8<43342>3C$$ • !*7I58D;$ • !"GH;2$ • !025D;$ • !M4>H$•!!4HD5$ • !MDJ8$ • !+82:E8;%-7.%61:4-05% • !"4-.0=3?.4-% • !@,%1>%ABBCD%AEDFBB%=2%6+G+63-5%1>%2349G12.0%34%-7.%HIJI%8.9%K5%

L.M+,%

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4%+1(4%,-&"#(131-&)5%-"

Slide 35: Earth is the only home we have and ever can have. Environmental chemistry and the practice of green chemistry and related areas such as industrial ecology are essential to sustaining our home. !"#$%&'(&$%!&)*+,&%)-!&.!&%"/!&"*0&!/!#&1"*&%"/!& !*/'#)*-!*$"+&1%!-'($#,&'(&!((!*$'"+&$)&(2($"'*'*3&)2#&%)-!& "&4567689:45&6;&!:975&:<&=>?@?A&;96B&<4:C?&><&<56@D&5?9?&>D&75?&E6@?9E6>D7&

49?

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