Finlayson-Pitts / Pitts Jr. / Jr. Chemistry of the Upper and Lower Atmosphere

Theory, Experiments, and Applications
1. Auflage 1999
ISBN: 978-0-08-052907-3
Verlag: Elsevier Science & Techn.
Format: EPUB
Kopierschutz: 6 - ePub Watermark

E-Book, Englisch, 969 Seiten

Here is the most comprehensive and up-to-date treatment of one of the hottest areas of chemical research. The treatment of fundamental kinetics and photochemistry will be highly useful to chemistry students and their instructors at the graduate level, as well as postdoctoral fellows entering this new, exciting, and well-funded field with a Ph.D. in a related discipline (e.g., analytical, organic, or physical chemistry, chemical physics, etc.). Chemistry of the Upper and Lower Atmosphere provides postgraduate researchers and teachers with a uniquely detailed, comprehensive, and authoritative resource. The text bridges the 'gap' between the fundamental chemistry of the earth's atmosphere and 'real world' examples of its application to the development of sound scientific risk assessments and associated risk management control strategies for both tropospheric and stratospheric pollutants.Serves as a graduate textbook and 'must have' reference for all atmospheric scientistsProvides more than 5000 references to the literature through the end of 1998Presents tables of new actinic flux data for the troposphere and stratospher (0-40km)Summarizes kinetic and photochemical date for the troposphere and stratosphereFeatures problems at the end of most chapters to enhance the book's use in teachingIncludes applications of the OZIPR box model with comprehensive chemistry for student use

Autoren/Hrsg.

Finlayson-Pitts, Barbara J.

Pitts Jr., James N.

Jr.,

Inhaltsverzeichnis

1;Cover;1
2;Contents;8
3;Preface;18
4;About the Authors;20
5;Acknowledgments;22
6;Chapter 1. Overview of the Chemistry of Polluted and Remote Atmospheres;24
6.1;A. REGIONS AND CHARACTERISTICS OF THE ATMOSPHERE ;25
6.2;B. AIR POLLUTION AND THE CHEMISTRY OF OUR TROPOSPHERE ;26
6.2.1;1. Historical Perspectives: Ancient and Medieval Times ;26
6.2.2;2. "London" Smog: Sulfur Dioxide, Acidic Aerosols, and Soot ;26
6.2.3;3. "Los Angeles" Smog: Ozone and Photochemical Oxidants ;27
6.2.4;4. Acid Deposition;31
6.3;C. CHEMISTRY OF THE NATURAL TROPOSPHERE: REMOTE ATMOSPHERES ;32
6.4;D. CHEMISTRY OF THE STRATOSPHERE;33
6.5;E. GLOBAL CLIMATE CHANGE;34
6.6;F. INDOOR AIR POLLUTION;36
6.7;G. DISCUSSION TOPIC AND OZIPR MODEL;36
6.7.1;1. Discussion Topic: "Background Ozone" ;36
6.7.2;2. OZIPR Model;36
6.8;REFERENCES;36
7;Chapter 2. The Atmospheric System;38
7.1;A. EMISSIONS;38
7.1.1;1. Oxides of Nitrogen;40
7.1.2;2. Volatile Organic Compounds (VOC);41
7.1.3;3. Carbon Monoxide;43
7.1.4;4. Sulfur Compounds;43
7.1.5;5. Total Suspended Particles (TSP), PM10, and PM2.5 ;44
7.1.6;6. Lead;48
7.2;B. METEOROLOGY;49
7.2.1;1. Lapse Rate: Temperature and Altitude;49
7.2.2;2. Potential Temperature;51
7.2.3;3. Temperature Inversions;51
7.3;C. REMOVAL FROM THE ATMOSPHERE: WET AND DRY DEPOSITION ;53
7.4;D. TYPICAL AMBIENT CONCENTRATIONS AND AIR QUALITY STANDARDS ;56
7.4.1;1. Units of Concentrations and Conversions;56
7.4.2;2. Criteria and Noncriteria Pollutants and Air Quality Standards ;58
7.5;E. EFFECTS ON VISIBILITY AND MATERIALS;60
7.6;F. ECONOMICS;61
7.7;G. ATMOSPHERIC CHEMISTRY: RISK ASSESSMENTS AND PUBLIC POLICIES FOR AIR POLLUTION CONTROL ;61
7.8;H. PROBLEMS;62
7.9;REFERENCES;62
8;Chapter 3. Spectroscopy and Photochemistry: Fundamentals;66
8.1;A. BASIC PRINCIPLES;66
8.1.1;1. Molecular Energy Levels and Absorption and Emission Spectroscopy ;66
8.1.2;2. Fates of Electronically Excited Molecules;73
8.2;B. ABSORPTION OF LIGHT;75
8.2.1;1. Basic Relationships;75
8.2.2;2. The Beer – Lambert Law;76
8.3;C. ATMOSPHERIC PHOTOCHEMISTRY;78
8.3.1;1. Solar Radiation and Its Transmission through the Atmosphere ;78
8.3.2;2. Calculating Photolysis Rates in the Atmosphere;84
8.3.3;3. Procedure for Calculating Photolysis Rates;99
8.3.4;4. Example: Photolysis of Acetaldehyde at the Earth's Surface ;104
8.4;D. PROBLEMS;106
8.5;REFERENCES;107
9;Chapter 4. Photochemistry of Important Atmospheric Species;109
9.1;A. MOLECULAR OXYGEN;109
9.1.1;1. Absorption Spectra;109
9.1.2;2. Photochemistry;112
9.2;B. OZONE;113
9.2.1;1. Absorption Spectra;113
9.2.2;2. Photochemistry;114
9.3;C. NITROGEN DIOXIDE;118
9.3.1;1. Absorption Spectra;118
9.3.2;2. Photochemistry;119
9.4;D. NITRIC ACID;121
9.5;E. NITROUS ACID;122
9.6;F. PEROXYNITRIC ACID;123
9.7;G. NITRATE RADICAL;123
9.8;H. DINITROGEN PENTOXIDE;124
9.9;I. NITROUS OXIDE;124
9.10;J. ORGANIC NITRATES AND PEROXYACETYL NITRATE ;125
9.10.1;1. Organic Nitrates;125
9.10.2;2. Peroxyacetyl Nitrate;126
9.11;K. SULFUR DIOXIDE AND SULFUR TRIOXIDE;126
9.11.1;1. SO2;126
9.11.2;2. SO3;128
9.12;L. HYDROGEN PEROXIDE AND ORGANIC HYDROPEROXIDES ;130
9.13;M. ALDEHYDES AND KETONES;130
9.14;N. CHLORINE NITRATE (ClONO2) AND BROMINE NITRATE (BrONO2) ;134
9.15;O. HCl AND HBr;136
9.16;P. THE HALOGENS;137
9.17;Q. ClO, BrO, AND IO;137
9.18;R. ClOOCl;137
9.19;S. OClO;138
9.20;T. HOCl, HOBr, AND HOI;138
9.21;U. NITROSYL CHLORIDE (ClNO) AND NITRYL CHLORIDE (ClNO2) ;140
9.22;V. HALOGENATED METHANES AND ETHANES ;140
9.23;W. PROBLEMS;140
9.24;REFERENCES;149
10;Chapter 5. Kinetics and Atmospheric Chemistry;153
10.1;A. FUNDAMENTAL PRINCIPLES OF GAS-PHASE KINETICS ;153
10.1.1;1. Definitions;153
10.1.2;2. Termolecular Reactions and Pressure Dependence of Rate Constants ;156
10.1.3;3. Temperature Dependence of Rate Constants;161
10.2;B. LABORATORY TECHNIQUES FOR DETERMINING ABSOLUTE RATE CONSTANTS FOR GAS-PHASE REACTIONS ;164
10.2.1;1. Kinetic Analysis;165
10.2.2;2. Fast-Flow Systems;165
10.2.3;3. Flash Photolysis Systems;168
10.2.4;4. Pulse Radiolysis;169
10.2.5;5. Cavity Ring Down Method;170
10.2.6;6. Static Techniques;171
10.3;C. LABORATORY TECHNIQUES FOR DETERMINING RELATIVE RATE CONSTANTS FOR GAS-PHASE REACTIONS ;172
10.4;D. REACTIONS IN SOLUTION;174
10.4.1;1. Interactions of Gaseous Air Pollutants with Atmospheric Aqueous Solutions ;174
10.4.2;2. Diffusion-Controlled Reactions of Uncharged Nonpolar Species in Solution ;175
10.4.3;3. Reactions of Charged Species in Solution;176
10.4.4;4. Experimental Techniques Used for Studying Solution Reactions ;178
10.5;E. LABORATORY TECHNIQUES FOR STUDYING HETEROGENEOUS REACTIONS ;179
10.5.1;1. Analysis of Systems with Gas- and Liquid-Phase Diffusion, Mass Accommodation, and Reactions in the Liquid Phase or at the Interface ;181
10.5.2;2. Knudsen Cells;188
10.5.3;3. Flow Tube Studies;190
10.5.4;4. Falling-Droplet Apparatus;190
10.5.5;5. Bubble Apparatus;191
10.5.6;6. Aerosol Chambers;191
10.5.7;7. Liquid Jet Apparatus;192
10.5.8;8. DRIFTS;194
10.5.9;9. Surface Science Techniques;194
10.5.10;10. Other Methods;195
10.6;F. COMPILATIONS OF KINETIC DATA FOR ATMOSPHERIC REACTIONS ;195
10.7;G. PROBLEMS;197
10.8;REFERENCES;198
11;Chapter 6. Rates and Mechanisms of Gas-Phase Reactions in Irradiated Organic – NOx – Air Mixtures;202
11.1;A. SOURCES OF OXIDANTS IN THE TROPOSPHERE: OH, O3, NO3, HO2, AND Cl ;202
11.1.1;1. OH;202
11.1.2;2. O3;203
11.1.3;3. NO3;203
11.1.4;4. HO2;203
11.1.5;5. Cl;203
11.2;B. LIFETIMES OF TYPICAL ORGANICS IN THE TROPOSPHERE ;204
11.3;C. REACTIONS OF ALKANES;205
11.3.1;1. Hydroxyl Radical (OH);205
11.3.2;2. Nitrate Radical (NO3);207
11.3.3;3. Chlorine Atoms (Cl);207
11.4;D. REACTIONS OF ALKYL (R), ALKYLPEROXY (RO2), AND ALKOXY (RO) RADICALS IN AIR ;208
11.4.1;1. Alkyl Radicals (R);208
11.4.2;2. Alkylperoxy Radicals (RO2);208
11.4.3;3. Alkoxy Radicals (RO);211
11.4.4;4. Summary of R, RO2, and RO Radical Reactions in the Troposphere ;214
11.5;E. REACTIONS OF ALKENES (INCLUDING BIOGENICS) ;214
11.5.1;1. Hydroxyl Radical (OH);214
11.5.2;2. Ozone (O3);219
11.5.3;3. Nitrate Radical (NO3);224
11.5.4;4. Chlorine Atoms (Cl);228
11.5.5;5. Nitrogen Dioxide (NO2);229
11.6;F. REACTIONS OF ALKYNES;229
11.6.1;1. Hydroxyl Radical (OH);229
11.7;G. REACTIONS OF SIMPLE AROMATIC HYDROCARBONS ;230
11.7.1;1. Hydroxyl Radical (OH);230
11.7.2;2. Nitrate Radical (NO3);235
11.7.3;3. Chlorine Atoms (Cl);235
11.8;H. REACTIONS OF OXYGEN-CONTAINING ORGANICS ;236
11.8.1;1. Reactions of OH, NO3, and Cl;236
11.8.2;2. Hydroperoxyl Radical (HO2);239
11.9;I. REACTIONS OF NITROGENOUS ORGANICS ;240
11.9.1;1. Peroxyacetyl Nitrate and Its Homologs;240
11.9.2;2. Alkyl Nitrates and Nitrites;243
11.9.3;3. Amines, Nitrosamines, and Hydrazines;244
11.10;J. CHEMISTRY OF REMOTE REGIONS;248
11.10.1;1. Emissions of Biogenic Organics;248
11.10.2;2. Chemistry;254
11.10.3;3. Upper Troposphere;262
11.10.4;4. Arctic;264
11.11;K. ATMOSPHERIC CHEMISTRY AND BIOMASS BURNING ;267
11.12;L. PROBLEMS;270
11.13;REFERENCES;271
12;Chapter 7. Chemistry of Inorganic Nitrogen Compounds;287
12.1;A. OXIDATION OF NO TO NO2 AND THE LEIGHTON RELATIONSHIP ;288
12.2;B. OXIDATION OF NO2;289
12.2.1;1. Daytime Gas-Phase Reaction with OH;289
12.2.2;2. Nighttime Reactions to Form NO3 and N2O5;290
12.2.3;3. Reactions of NO and NO2 with Water and Alcohols ;291
12.2.4;4. Other Reactions of NO2;295
12.3;C. ATMOSPHERIC CHEMISTRY OF HONO;296
12.3.1;1. Formation of HONO;296
12.3.2;2. Atmospheric Fates of HONO;297
12.4;D. REACTIONS OF NO3 AND N2O5;299
12.4.1;1. Reactions of NO3;299
12.4.2;2. Reactions of N2O5;302
12.5;E. ATMOSPHERIC CHEMISTRY OF HNO3;304
12.5.1;1. Formation;304
12.5.2;2. Tropospheric Fates;304
12.6;F. "MISSING" NOy;309
12.7;G. AMMONIA (NH3);309
12.8;H. PROBLEMS;310
12.9;REFERENCES;311
13;Chapter 8. Acid Deposition: Formation and Fates of Inorganic and Organic Acids in the Troposphere;317
13.1;A. CONTRIBUTION OF H2SO4, HNO3, HONO, AND ORGANIC ACIDS ;317
13.2;B. SOLUBILITY OF GASES IN RAIN, FOGS, AND CLOUDS: HENRY'S LAW AND AQUEOUS-PHASE EQUILIBRIA ;318
13.3;C. OXIDATION OF SO2;319
13.3.1;1. Field Studies;319
13.3.2;2. Oxidation in the Gas Phase;321
13.3.3;3. Oxidation in the Aqueous Phase;324
13.3.4;4. Oxidation on Surfaces;347
13.3.5;5. Relative Importance of Various Oxidation Pathways for SO2 ;348
13.4;D. ORGANIC ACIDS;349
13.5;E. OXIDATION OF SULFUR COMPOUNDS OTHER THAN SO2 ;351
13.5.1;1. Reactions of Dimethyl Sulfide (CH3SCH3);352
13.5.2;2. Dimethyl Disulfide (CH3SSCH3);357
13.5.3;3. Methyl Mercaptan (CH3SH);357
13.5.4;4. Hydrogen Sulfide (H2S);358
13.5.5;5. Carbon Disulfide (CS2);358
13.5.6;6. Carbonyl Sulfide (COS);359
13.6;F. PROBLEMS;359
13.7;REFERENCES;360
14;Chapter 9. Particles in the Troposphere;372
14.1;A. PHYSICAL PROPERTIES;372
14.1.1;1. Some Definitions;372
14.1.2;2. Size Distributions;374
14.1.3;3. Particle Motion;385
14.1.4;4. Light Scattering and Absorption and Their Relationship to Visibility Reduction ;388
14.2;B. REACTIONS INVOLVED IN PARTICLE FORMATION AND GROWTH ;398
14.2.1;1. Nucleation, Condensation, and Coagulation;398
14.2.2;2. Reactions of Gases at Particle Surfaces;402
14.2.3;3. Reactions in the Aqueous Phase;403
14.2.4;4. Relative Importance of Various Aerosol Growth Mechanisms ;403
14.3;C. CHEMICAL COMPOSITION OF TROPOSPHERIC AEROSOLS ;403
14.3.1;1. Inorganic Species;404
14.3.2;2. Organics;416
14.4;D. GAS – PARTICLE DISTRIBUTION OF SEMIVOLATILE ORGANICS ;435
14.4.1;1. Adsorption on Solid Particles;436
14.4.2;2. Absorption into Liquids;440
14.4.3;3. Octanol – Air Partitioning Coefficients;443
14.5;E. PROBLEMS;446
14.6;REFERENCES;446
15;Chapter 10. Airborne Polycyclic Aromatic Hydrocarbons and Their Derivatives: Atmospheric Chemistry and Toxicological Implications;459
15.1;A. NOMENCLATURE AND SELECTED PHYSICAL AND SPECTROSCOPIC PROPERTIES OF POLYCYCLIC AROMATIC HYDROCARBONS (PAHs) AND POLYCYCLIC AROMATIC COMPOUNDS (PACs) ;463
15.1.1;1. Combustion-Generated PAHs and PACs;463
15.1.2;2. Structures and IUPAC Rules for Nomenclature;463
15.1.3;3. Solubilities and Vapor Pressures;474
15.1.4;4. Gas – Particle Partitioning, Sampling Techniques, and Ambient Levels of Selected PAHs and PACs ;476
15.1.5;5. Absorption and Emission Spectra of Selected PAHs and PACs ;484
15.2;B. BIOLOGICAL PROPERTIES OF PAHs AND PACs. I: CARCINOGENICITY ;489
15.2.1;1. Historical Perspective: Benzo[a]pyrene, the "Classic Chemical Carcinogen" ;489
15.2.2;2. Carcinogenicity of PAHs, Cancer Potencies, and Potency Equivalence Factors ;490
15.2.3;3. Carcinogenicity of Nitroarenes and Other Nitro-PACs ;496
15.3;C. BIOLOGICAL PROPERTIES OF PAHs AND PACs. II: MUTAGENICITY ;498
15.3.1;1. Short-Term Tests for Genetic and Related Effects;498
15.3.2;2. The Ames Salmonella typhimurium Reversion Assay ;498
15.3.3;3. The Salmonella TM677 "Forward Mutation" Assay ;506
15.3.4;4. Human Cell Mutagenicities of PAHs and PACs;507
15.4;D. BACTERIAL AND HUMAN CELL MUTAGENICITIES OF POLLUTED AMBIENT AIR ;509
15.4.1;1. Bacterial Mutagenicity of Urban Air: A Worldwide Phenomenon ;509
15.4.2;2. Sources, Ambient Levels, Transport, and Transformation: Some Case Studies ;514
15.4.3;3. Bioassay-Directed Chemical Analysis for PAHs and PACs in Fine Ambient Aerosols Using a Human Cell Assay ;520
15.4.4;4. Bioassay-Directed Chemical Analysis for Vapor-Phase and Particle-Phase PAHs and PACs in Ambient Air Using Bacterial Assays ;525
15.5;E. ATMOSPHERIC FATES OF PARTICLE-ASSOCIATED PAHs: HETEROGENEOUS REACTIONS ;527
15.5.1;1. Background;527
15.5.2;2. Theoretical and Experimental Structure – Reactivity Relationships ;528
15.5.3;3. Field Studies of Atmospheric Reactions: Transport and Transformation ;530
15.5.4;4. Photochemical Reactions of Particle-Associated PAHs ;533
15.5.5;5. Gas – Particle Reactions;536
15.5.6;6. Atmospheric Fates of Particle-Associated Nitroarenes ;541
15.6;F. REACTIONS OF GAS-PHASE PAHs: ATMOSPHERIC FORMATION OF MUTAGENIC NITROARENES ;542
15.6.1;1. Combustion-Generated Primary Emissions of Nitroarenes ;542
15.6.2;2. Atmospheric Formation of Nitro-PAHs and Nitro-PACs ;543
15.7;REFERENCES;550
16;Chapter 11. Analytical Methods and Typical Atmospheric Concentrations for Gases and Particles;570
16.1;A. GASES;571
16.1.1;1. Optical Spectroscopic Techniques;571
16.1.2;2. Mass Spectrometry;584
16.1.3;3. Filters, Denuders, Transition Flow Reactors, Mist Chambers, and Scrubbers ;590
16.1.4;4. Methods for, and Tropospheric Levels of, Specific Gases ;592
16.1.5;5. Generation of Standard Gas Mixtures;630
16.2;B. PARTICLES;631
16.2.1;1. Sampling and Collection of Particles;631
16.2.2;2. Measurement of Physical Characteristics: Mass and Size ;635
16.2.3;3. Measurement of Chemical Composition;642
16.2.4;4. Real-Time Monitoring Techniques for Particles;649
16.2.5;5. Generation of Calibration Aerosols;655
16.3;C. PROBLEMS;658
16.4;REFERENCES;659
17;Chapter 12. Homogeneous and Heterogeneous Chemistry in the Stratosphere;680
17.1;A. CHEMISTRY OF THE UNPERTURBED STRATOSPHERE ;680
17.1.1;1. Stratosphere – Troposphere Exchange (STE);681
17.1.2;2. Chapman Cycle and NOx Chemistry;683
17.2;B. HIGH-SPEED CIVIL TRANSPORT (HSCT), ROCKETS, AND THE SPACE SHUTTLE;685
17.2.1;1. HSCT;685
17.2.2;2. Space Shuttle and Solid Rocket Motors;690
17.3;C. CHLOROFLUOROCARBONS;692
17.3.1;1. Types, Nomenclature, and Uses;692
17.3.2;2. Lifetimes and Atmospheric Fates of CFCs and Halons ;693
17.3.3;3. Gas-Phase Chemistry in the Stratosphere;696
17.3.4;4. Antarctic "Ozone Hole";698
17.3.5;5. Polar Stratospheric Clouds (PSCs) and Aerosols ;703
17.3.6;6. Effects of Volcanic Eruptions;713
17.3.7;7. Ozone Depletion in the Arctic;719
17.3.8;8. Ozone Destruction in the Midlatitudes;723
17.4;D. CONTRIBUTION OF BROMINATED ORGANICS ;724
17.4.1;1. Sources and Sinks of Brominated Organics;724
17.4.2;2. Bromine Chemistry in the Stratosphere;725
17.5;E. CONTRIBUTION OF IODINE-CONTAINING ORGANICS ;729
17.6;F. SUMMARY;730
17.7;G. PROBLEMS;730
17.8;REFERENCES;731
18;Chapter 13. Scientific Basis for Control of Halogenated Organics;750
18.1;A. INTERNATIONAL AGREEMENTS ON PHASEOUT OF HALOGENATED ORGANICS ;750
18.2;B. OZONE DEPLETION POTENTIALS (ODP);753
18.3;C. TRENDS IN CFCs, THEIR REPLACEMENTS, STRATOSPHERIC O3, AND SURFACE UV;756
18.3.1;1. Trends in CFCs and Their Replacements;756
18.3.2;2. Trends in Stratospheric O3;759
18.3.3;3. Trends in Surface Ultraviolet Radiation;764
18.4;D. TROPOSPHERIC CHEMISTRY OF ALTERNATE CFCs ;767
18.4.1;1. Kinetics of OH Reactions;767
18.4.2;2. Tropospheric Chemistry;769
18.5;E. SUMMARY;776
18.6;F. PROBLEMS;776
18.7;REFERENCES;776
19;Chapter 14. Global Tropospheric Chemistry and Climate Change;785
19.1;A. RADIATION BALANCE OF THE ATMOSPHERE: THE GREENHOUSE EFFECT ;786
19.1.1;1. Global Absorption and Emission of Radiation;786
19.1.2;2. Radiative Transfer Processes in the Atmosphere;789
19.1.3;3. Dependence of Net Infrared Absorption on Atmospheric Concentrations ;792
19.2;B. CONTRIBUTION OF TRACE GASES TO THE GREENHOUSE EFFECT ;793
19.2.1;1. Infrared Absorption by Trace Gases;793
19.2.2;2. Trends in Trace Gas Concentrations;796
19.2.3;3. Radiative Forcing by Greenhouse Gases and Global Warming Potentials ;806
19.3;C. AEROSOL PARTICLES, ATMOSPHERIC RADIATION, AND CLIMATE CHANGE;811
19.3.1;1. Direct Effects;812
19.3.2;2. Indirect Effects of Aerosol Particles;822
19.4;D. SOME OTHER FACTORS AFFECTING GLOBAL CLIMATE ;837
19.4.1;1. Absorption of Solar Radiation by Clouds;837
19.4.2;2. Feedbacks: Water Vapor, Clouds, and the "Supergreenhouse Effect" ;842
19.4.3;3. Solar Variability;844
19.4.4;4. Volcanic Eruptions;845
19.4.5;5. Oceans ;845
19.5;E. OBSERVATIONS OF CLIMATE CHANGES;846
19.5.1;1. Observed Temperature Trends;846
19.5.2;2. Other Climate Changes;851
19.6;F. THE FUTURE;851
19.7;G. PROBLEMS;852
19.8;REFERENCES;852
20;Chapter 15. Indoor Air Pollution: Sources, Levels, Chemistry, and Fates;867
20.1;A. RADON;867
20.2;B. OXIDES OF NITROGEN;869
20.2.1;1. Levels of NOx;869
20.2.2;2. HONO and HNO3;870
20.3;C. CO AND SO2;872
20.4;D. VOLATILE ORGANIC COMPOUNDS;873
20.5;E. OZONE;882
20.6;F. INDOOR VOC – NOx – O3 CHEMISTRY;882
20.7;G. PARTICLES;884
20.8;H. PROBLEMS;888
20.9;REFERENCES;888
21;Chapter 16. Applications of Atmospheric Chemistry: Air Pollution Control Strategies and Risk Assessments for Tropospheric Ozone and Associated Photochemical Oxidants, Acids, Particles, and Hazardous Air Pollutants;894
21.1;A. TROPOSPHERIC OZONE AND ASSOCIATED PHOTOCHEMICAL OXIDANTS ;894
21.1.1;1. Environmental Chambers;895
21.1.2;2. Isopleths for Ozone and Other Photochemically Derived Species ;905
21.1.3;3. Models;909
21.2;B. REACTIVITY OF VOC;930
21.2.1;1. Typical Reactivity Scales;930
21.2.2;2. Application to Control of Mobile Source Emissions ;932
21.3;C. FIELD OBSERVATIONS OF VOC, NOx , AND O3 ;936
21.4;D. ALTERNATE FUELS;941
21.4.1;1. Reformulated Gasolines;941
21.4.2;2. Compressed Natural Gas (CNG);942
21.4.3;3. Liquefied Petroleum Gas (LPG);943
21.4.4;4. Alcohol Fuels and Blends with Gasoline;943
21.4.5;5. Hydrogen;944
21.4.6;6. Electric Vehicles;944
21.5;E. CONTROL OF ACIDS;944
21.6;F. CONTROL OF PARTICLES;946
21.7;G. ATMOSPHERIC CHEMISTRY AND RISK ASSESSMENTS OF HAZARDOUS AIR POLLUTANTS ;948
21.8;H. PROBLEMS;953
21.9;REFERENCES;955
22;Appendix I: Enthalpies of Formation of Some Gaseous Molecules, Atoms, and Free Radicals at 298 K;966
23;Appendix II: Bond Dissociation Energies;968
24;Appendix III: Running the OZIPR Model;970
25;Appendix IV: Some Relevant Web Sites;972
26;Appendix V: Pressures and Temperatures for Standard Atmosphere ;974
27;Appendix VI: Answers to Selected Problems;975
28;Subject Index;980

Leseproben

CHAPTER 2 The Atmospheric System As discussed in Chapter 1, much of our understanding of the chemistry of our atmosphere is based on early studies of air pollution; these are often treated in the context of an overall “system.” This approach starts with the various sources of anthropogenic and natural emissions and tracks the resulting pollutants through their atmospheric transport, transformations, and ambient concentrations—on local, regional, and global scales—to their ultimate chemical and physical fates, including their impacts on our health and environment. Figure 2.1 is a simplified diagram illustrating the major elements. Primary pollutants are defined as those emitted directly into the air, e.g., SO2, NO, CO, Pb, organics [including HAPS (hazardous air pollutants)], and combustion-generated particulate matter (PM). Sources may be anthropogenic, biogenic, geogenic, or some combination thereof. Once in the atmosphere, they are subjected to dispersion and transport, i.e., meteorology, and simultaneously to chemical and physical transformations into gaseous and particulate secondary pollutants; the latter are defined as those formed from reactions of the primary pollutants in air. Both primary and secondary pollutants are removed at the earth’s surface via wet or dry deposition and, in the processes of transport, transformation, and deposition, can impact a variety of receptors, for example, humans, animals, aquatic ecosystems, forests and agricultural crops, and materials. FIGURE 2.1 The atmospheric air pollution system. From a detailed knowledge of the emissions, topography, meteorology, chemistry, and deposition processes, one can develop mathematical models that predict the concentrations of primary and secondary pollutants as a function of time at various locations. Depending on the particular model, these may describe pollutant concentrations over a variety of scales: • In a plume from a specific point source (plume models) • In an air basin from a combination of diverse mobile and stationary sources (airshed models) • Over a large geographical area downwind from a group of sources (long-range transport and regional models) • Over the entire earth (global models) To test these models, their predictions must be compared to the observed concentrations of various species; model inputs are adjusted to obtain acceptable agreement between the observed and predicted values. These models can then be used, in combination with the documented impacts on receptors, to develop health and/or environmental risk assessments and various control strategy options. Finally, through legislative and administrative action, health-protective and cost-effective risk-management decisions can be made, and regulatory actions implemented, that directly affect the starting point of our atmospheric system, that is, the primary emissions and their sources. To place the remainder of this book on atmospheric chemistry in perspective, the various components of our “atmospheric system” are treated briefly next. A. EMISSIONS
In describing a given air mass and the chemical reactions occurring therein, one must consider both natural and anthropogenic sources of primary emissions and evaluate their relative importance. Thus the impact on air quality of natural emissions can be an important issue because cost-effective control strategies must take into account the relative strengths of emissions from all sources, not just those of anthropogenic origin. However, it is not only the relative amounts of total emissions that must be considered but also the chemical nature of the emissions, e.g., their reactivities and their temporal and spatial distributions. Emissions inventories are typically obtained by combining the rate of emissions from various sources (the “emission factors”) with the number of each type of source and the time over which the emissions occur. Inventories are compiled in various formats. For example, they can be assembled for various individual anthropogenic processes such as refining, or natural processes such as volcanic eruptions, in which emissions of all of the relevant species associated with that event are estimated. Alternatively, and more commonly, emissions inventories are compiled by species, showing the various sources that contribute to the total emissions of each. Emission factors for various sources in the United States have been published by the Environmental Protection Agency in the form of the documentAIRCHIEF, short for the Air Clearing House for Inventories and Emission Factors. Such data are available on CD-ROM as well as on-line through the EPA Web site (see Appendix IV). In Europe, the Commission of the European Communities has published a handbook of emission factors as well (e.g., see CEC (1988, 1989, 1991), McInnes (1996), and Web site in Appendix IV). Emissions inventories and emission factors for Europe are also found in the volume edited by Fenger et al. (1998). On a global scale, emissions inventories for a variety of species are currently under development under the auspices of the International Global Atmospheric Chemistry Project (IGAC), and various available inventories are described by Graedel et al. (1993). Data for some of the major pollutants follow. 1. Oxides of Nitrogen
We shall follow here the convention in current use that defines NOx as the sum of (NO + NO2) and NOy as the sum of all reactive nitrogen-containing species, e.g., NOy = (NO + NO2 + HNO3 + PAN + HONO + NO3 + N2O5 + organic nitrates etc.). By far the most significant species emitted by anthropogenic processes is nitric oxide, produced when N2 and O2 in air react during high-temperature combustion processes. In addition, some NOx is formed from nitrogen in the fuel. Smaller amounts of NO2 are produced by the further oxidation of NO; trace amounts of other nitrogenous species such as HNO3 are also formed. The fraction of the total that is emitted as NO clearly depends on the conditions associated with the specific combustion process. While most (typically > 90%) of the NOx emitted is believed to be in the form of NO, the fraction of NO2 can vary from less than 1% to more than 30% (e.g., Lenner, 1987). Figure 2.2 shows the contribution of various sources to the total anthropogenic NOx emissions, 23 × 106 short tons, or 21 Tg (expressed as NO2), in the United States in 1996 (1 Tg = 1 teragram = 1012 g and one short ton = 0.907 × 106 g). This can be compared to total global anthropogenic emissions of approximately 72 Tg of NOx (expressed as NO2) (Müller, 1992). FIGURE 2.2 Contribution of various sources to total anthropogenic NOx emissions in the United States in 1996. (from EPA, 1999) Figure 2.3 shows the trend in NOx emissions for North America, Europe, the USSR, and Asia from 1970 to 1986 (Hameed and Dignon, 1992). While those of North America and Europe have decreased or leveled off, those from Asia and the USSR increased significantly, a trend that has continued. Figure 2.4a shows the geographical pattern of the emission flux of NOx in Asia in 1987 (Akimoto and Narita, 1994). Clearly, Japan and China are major contributors to the flux of NOx in this region, with the City of Tokyo having the highest emission flux rate. FIGURE 2.3 NOx emissions in million tons of equivalent NO2 for the period 1970 to 1986 for Asia, Europe, North America, and the USSR. (from Hameed and Dignon, 1992) FIGURE 2.4 (a) Pattern of 1987 annual emission flux of NOx. in Asia (in units of millimoles as N per m2 per year) (from Akimoto and Narita, 1994). (b) Estimated relative rates of biogenic emissions of NO in the United States in 1990. (from EPA, 1995) There are also significant natural sources of oxides of nitrogen, in particular nitric oxide, which is produced by biomass burning as well as by soils where nitrification, denitrification, and the decomposition of nitrite (NO2-) contribute to NO production. Figure 2.4b, for example, shows the relative emission rates for biogenically produced NO in the United States in 1990 (EPA, 1995). Another important natural source is NOx produced by lightning, with recent estimates in the range of 10–33 Tg yr-1 as NO2 (Flatøy and Hov, 1997; Price et al., 1997a, 1997b; Wang et al., 1998). By comparison to the estimated emissions from biomass burning and continental biogenic sources (Table 2.1), it is seen that lightning is quite important. TABLE 2.1 Global Emission Estimates for CO, NOx, CH4, and VOC from Both Anthropogenic and Natural Sources (in Tg/yr)a There is also some NO produced from the oxidation of NH3 by photochemical processes in oceans and by some terrestrial...