15
High
Ozone
Concentrations
in
Nonurban
Downloaded via UNIV OF ROCHESTER on July 29, 2018 at 07:30:26 (UTC). See https://pubs.acs.org/sharingguidelines for options on how to legitimately share published articles.
Atmospheres
LYMAN A. RIPPERTON, JOSEPH E. SICKLES, W. CARY EATON, CLIFFORD E. DECKER, and WALTER D. BACH Research Triangle Institute, Research Triangle Park, N. C. 27711
The N a t i o n a l Ambient Air Q u a l i t y Standard f o r photochemical oxidant(1) was set in 1971 as
178
REMOVAL
O F TRACE CONTAMINANTS F R O M
T H E AIR
Θ ΚΑΝΕ, ΡΑ. Δ COSHOCTON, OHIO /
^Δ ^Δ-Λ
· LEWISBURG,W. VA.
ε οίο α. ο ο. χ οΖ Q Ο lu
w
Ζ
£
Θ—Ο—©·
g ËJ005I
J 0000 0200 0400 0600 0800
1000
I
I
L
1200
1400
1600
J 1800
L
2000 2200
0000
TIME OF DAY (EDT)
Figure
3.
Mean
diurnal
nitrogen tember
dioxide
concentrations,
June
26-Sep-
30,1973
FLIGHT DATE-9/11/73 I - 900'
ABOVE TERRAIN
Δ- GROUND ELEVATION
PPM
EDT
.045
τ
13©
.047
4
1325
.076
4- 1327
.086 -J- 1329
.093 .091
1335
Δ2301* LEWISBURG, W. VA. STATION DATA PPM HOUR .093 1315 .095
1330
.097
1345
.098 .100
1400 1415
Figure
4.
Vertical ozone measurements, September 11,1973
Deitz; Removal of Trace Contaminants from the Air ACS Symposium Series; American Chemical Society: Washington, DC, 1975.
15.
RiPPERTON E T A L .
High
Ozone
Concentrations
179
I t s h o u l d be noted a l s o t h a t t h e l a r g e p e r c e n t o f time t h a t t h e h i g h c o n c e n t r a t i o n s e x i s t e d and t h e p e r i o d o f t i m e ( n e a r l y f o u r months) t h a t h i g h c o n c e n t r a t i o n s were observed argues a g a i n s t a s t r a t o s p h e r i c o r i g i n o f t h e ozone r e p o r t e d i n t h i s s tudy. A l t h o u g h o n l y n i n e h y d r o c a r b o n samples were t a k e n a t t h e s t a t i o n s i n t h e c o u r s e o f t h e 1973 s t u d y , a c e t y l e n e was f o u n d i n a l l o f them, a t c o n c e n t r a t i o n s r a n g i n g f r o m 2 t o 63 p a r t s p e r b i l l i o n (ppb). I t i s w e l l known t h a t a c e t y l e n e h a s no known sources other than anthropogenic.(6) The CO c o n c e n t r a t i o n s i n t h e s a m p l e s r a n g e d f r o m 0.27 t o 0/46 ppm. A l t h o u g h n a t u r a l b a c k g r o u n d v a r i e s , i t i s g e n e r a l l y c o n s i d e r e d t o r a n g e b e t w e e n .08 t o .12 ppm. T h e s e d a t a i n d i c a t e t h e p r e s e n c e o f a n t h r o p o g e n i c pollution. The m e a s u r e d N O 2 c o n c e n t r a t i o n s were l o w , 0.005 t o 0.030 ppm, b u t a r e s t i l l g r e a t e r t h a n t h o s e c o n s i d e r e d a s b a c k g r o u n d , a b o u t 0.008 ppm. T h i s i s a n o t h e r i n d i c a t i o n o f a n t h r o p o genic sources. T h e s e d a t a r e v e a l t h e c o n s t a n t p r e s e n c e o f some a n t h r o p o g e n i c p o l l u t i o n w h i c h r e f u t e s t h e argument t h a t t h e s y n t h e s i s o f h i g h c o n c e n t r a t i o n s o f O 3 i s accomplished from n a t u r a l precursors only. I t s h o u l d be p o i n t e d o u t t h a t n a t u r a l e m i s s i o n s o f b o t h o r g a n i c v a p o r s and o f o x i d e s o f n i t r o g e n ( 7 ) o c c u r and t h e s e w i l l e n t e r i n t o t h e ozone g e n e r a t i v e p r o c e s s e s and p a r t i c i p a t e i n t h e same k i n d s o f p h o t o c h e m i c a l r e a c t i o n s a s t h e i r a n t h r o p o g e n i c counterparts.(8) The t r a n s p o r t o f O 3 , e s p e c i a l l y a l o f t , w i t h i n a f e w t h o u s a n d f e e t o f , b u t o u t o f touch w i t h , t h e ground, has been demonstrated. (9) However, t h e f a c t t h a t a l o c a t i o n l i k e I n d i o ( p o p u l a t i o n a b o u t 14,000) c a n e x c e e d t h e NAAQS more f r e q u e n t l y t h a n a n y o t h e r sampling s i t e i n C a l i f o r n i a ( 1 0 ) (e.g., Los Angeles, R i v e r s i d e ) i s c l e a r p r o o f t h a t O 3 s y n t h e s i s does n o t s t o p a t t h e c i t y l i m i t s b u t c o n t i n u e s a s t h e p h o t o c h e m i c a l s y s t e m t r a v e l s downwind. I f i t i s a d m i t t e d t h a t t h e O 3 measured i n h i g h c o n c e n t r a tions i n our f i e l d synthesized i n the troposphere, the l a r g e q u e s t i o n t h a t remains i s : i f t h e p r e c u r s o r s a r e n o t a l l n a t u r a l , w h e r e do t h e y come f r o m a n d d o e s a n t h r o p o g e n i c p o l l u t i o n h a v e a s p e c i a l r o l e i n g e n e r a t i n g t h e h i g h nonurban c o n c e n t r a t i o n s o f 0 ? A l t h o u g h F i g u r e 6 shows t h a t t h e t r a j e c t o r i e s o f a i r a r r i v i n g a t K a n e , P e n n s y l v a n i a i n t h e summer o f 1973 w h i c h c o u l d b r i n g h i g h c o n c e n t r a t i o n s o f O 3 , more t r a j e c t o r i e s f r o m t h e same l o c a t i o n s n o t e d o n t h e map h a d l o w c o n c e n t r a t i o n s o f O 3 ( i . e . , NO + 0
0 + 0 +M—>0 +M 2
NO + 0
3
3
-> N0 + 0
2
No Net 0
3
2
NO O x i d a t i o n (Non-0j —) 0
NO + R00 —> N0 + R02
0 0 RCOO* + NO —>• N0 + RCO* 2
H0 * + NO —> N0 + Η0· 2
2
One 0^ Netted f o r Each NO Oxidized P e r o x y - r a d i c a l Formation RH + -OH —>• R* + H 0 2
0 Ο RCH + ·0Η — * RC- + H 0 2
R- + 0
— * ROO*
2
0
Ο
RC* + 0
R C 0 2
°*
Selected Hydroxyl R a d i c a l Formation Schemes HO 1.
NO + N0 -=—> 2HONO 2
HONO + hV —>• N0 + ·ΟΗ 0 2
2.
H C=0 + hV —>• Η· + H O 2
Η· + 0
2
— • Η00·
Ο H
0
+
C
HC* +02"-* ° " ° Η00· + NO —y NO + ·0Η 3.
o
3
+ hv
ο oh)) + o
2
H 0 + 0("h>) —> 2·0Η 2
Table 2.
Selected Reactions Involved i n Ozone Generation
Deitz; Removal of Trace Contaminants from the Air ACS Symposium Series; American Chemical Society: Washington, DC, 1975.
15.
High
RIPPERTON E T A L .
Ozone
Concentrations
185
kinds o f r e a c t i o n s a r e i n v o l v e d i n generating the O 3 i n the nonurban areas t h a t a r e a l s o o p e r a t i v e i n t h e urban atmosphere, t h i s w i l l be more a m a t t e r o f r e l a t i v e r a t e s t h a n o f new r e a c t i o n s . F i e l d and chamber measurements o f s t a b l e i n t e r m e d i a t e s i n t h e HC-N0 -03-hV s y s t e m a r e e m i n e n t l y d e s i r a b l e f o r p r o p e r i n t e r p r e t a t i o n o f such c h e m i c a l r e l a t i o n s h i p s . x
Conclusions A i r i n t h e a r e a o f s t u d y ( O h i o , P e n n s y l v a n i a , M a r y l a n d and West V i r g i n i a ) i n w h i c h h i g h O 3 c o n c e n t r a t i o n s w e r e g e n e r a t e d had e v i d e n c e o f a n t h r o p o g e n i c c o n t a m i n a t i o n ( o t h e r t h a n O 3 ) . T h i s a i r a p p e a r e d n o t t o come a l w a y s f r o m a s p e c i f i c g e o g r a p h i c a l location. The O 3 g e n e r a t i v e c a p a c i t y o f t h e s y s t e m i s j u d g e d by t h e a u t h o r s t o b e a n a i r mass c h a r a c t e r i s t i c . The O 3 i s p o s t u l a t e d a s b e i n g g e n e r a t e d i n a r e l a t i v e l y "spent photochemical system." The s y s t e m i s r e f e r r e d t o a s " r e l a t i v e l y spent" because there i s evidence o f continuous i n j e c t i o n o f a s m a l l amount o f p o l l u t i o n . The a u t h o r s h a v e p r e s e n t e d a rough paradigm i n which t h e c a p a c i t y o f t h e s o - c a l l e d spent pho t o c h e m i c a l system t o generate O 3 from l o w c o n c e n t r a t i o n s o f N 0 ( i . e . , 5-20 ppb N 0 ) i s due t o a r e d u c e d c a p a c i t y o f t h e s y s t e m t o d e s t r o y O 3 a n d a n enhancement o f t h e r a t e o f O 3 a c c u m u l a t i o n due t o r e a c t i o n s i n v o l v i n g s t a b l e i n t e r m e d i a t e s w h i c h p r o v i d e a s o u r c e o f ·0Η r a d i c a l s . The r o l e o f c o n t a m i n a t e d c i t y a i r i s t o p r o v i d e a source of t h e s t a b l e i n t e r m e d i a t e s g r e a t e r than would occur i n nature. X
X
Literature Cited 1. 2. 3.
4.
5.
6.
Federal Register (April 3 0 , 1 9 7 1 ) , 36 ( N o . 84), 8187. J u n g e , C . Ε., "Air C h e m i s t r y and Radioactivity," pp. 37-59, A c a d e m i c Press, New Y o r k ( 1 9 6 3 ) . Research Triangle Institute, "Investigation o f Ozone and Ozone Precursor C o n c e n t r a t i o n s a t N o n u r b a n Locations in t h e Eastern United States," R e s e a r c h Triangle P a r k , N.C. ( 1 9 7 4 ) . (Also issued as E n v i r o n m e n t a l Protection Agency Report No. 450/3-74-034.) Richter, H . G., "Special Ozone and O x i d a n t Measurements i n the Vicinity o f Mount S t o r m , West Virginia," RTI Task No. 3, NAPCA C o n t r a c t N o . 7 0 - 1 4 7 , R e s e a r c h Triangle P a r k , N.C. (1970). Research Triangle Institute, "Investigation o f H i g h Ozone Con centrations in the Vicinity o f Garrett C o u n t y , M a r y l a n d and Preston County, West Virginia," R e s e a r c h Triangle P a r k , N.C. (1973). ( A l s o issued as E n v i r o n m e n t a l Protection Agency Report No. 450/3-75-036.) Miller, S. Α., "Acetylene: Its Properties, M a n u f a c t u r e and Uses," A c a d e m i c Press, New Y o r k ( 1 9 6 5 ) .
Deitz; Removal of Trace Contaminants from the Air ACS Symposium Series; American Chemical Society: Washington, DC, 1975.
186
7.
8.
9.
10. 11.
12.
13.
R E M O V A L O F T R A C E C O N T A M I N A N T S F R O M T H E AIR
Robinson, E . and R. C. Robbins, "Sources, Abundance and Fate of Gaseous Atmospheric Pollutants," Stanford Research Insti tute P r o j e c t PR-6755, prepared f o r American Petroleum Insti tute, New York (1968). R i p p e r t o n , L . A . and D. Lillian, "The E f f e c t of Water Vapor on Ozone Synthesis in the P h o t o - o x i d a t i o n of Alpha-Pinene," J . Air Poll. C o n t r o l Assoc. (1971) 21:629-635. L e a , D. Α . , "Vertical Ozone Distribution in the Lower Tropo sphere Near an Urban Pollution Center," J . A p p l . Meteor. (1968) 7:252-267. Maga, John, California Air Resources Board, personal commu nication. Niki, H., C. E . Daby, B . Weinstock, "Mechanics of Smog For mation," p r e p r i n t of Fuel Science Department, Ford Motor C o r p o r a t i o n , presented 101st N a t i o n a l Meeting, American Chemical S o c i e t y , Los Angeles, California (1971). Fox, D. L., R. Kamens, Η. E . Jeffries, "Photochemical Smog Systems: E f f e c t s of Dilution on Ozone Formation," Science (1975) 188:1113-1114. Demerjian, K . L., J . A . K e r r , J . G. C a l v e r t , "Mechanism of Photochemical Smog Formation," in Advances in Environmental Science and Technology, Vol. 4, pp. 1-262, J. N . Pitts, R. M e t c a l f , eds, John W i l e y , New York (1974).
Deitz; Removal of Trace Contaminants from the Air ACS Symposium Series; American Chemical Society: Washington, DC, 1975.