90 AIR POLLUTION SOURCES
TABLE 11
Ozone Levels Generated in Photoxidation* of various Hydrocarbons with
Oxides of NitrogenHydrocarbon Ozone Level (ppm) Time (min)Isobutene 1.00 28
2-Methyl-1,3-butadiene 0.80 45
trans-2-Butene 0.73 35
3-Heptene 0.72 60
2-Ethyl-1-butene 0.72 80
1,3-Pentadiene 0.70 45
Propylene 0.68 75
1,3-Butadiene 0.65 45
2,3-Dimethyl-1,3-butadiene 0.65 45
2,3-Dimethyl-2-butene 0.64 70
1-Pentene 0.62 45
1-Butene 0.58 45
cis-2-Butene 0.55 35
2,4,4-Trimethyl-2-pentene 0.55 50
1,5-Hexadiene 0.52 85
2-Methylpentane 0.50 170
1,5-Cyclooctodiene 0.48 65
Cyclohexene 0.45 35
2-Methylhepatane 0.45 180
2-Methyl-2-butene 0.45 38
2,2,4-Trimethylpentane 0.26 80
3-Methylpentane 0.22 100
1,2-Butadiene 0.20 60
Cyclohexane 0.20 80
Pentane 0.18 100
Methane 0.0 —* Reference 10.Part 1. Pollutant Emissions (continued)Pollutant types Sources and abundance Abatement and controlHalides
a. Chlorine:Chlorine (Cl 2 ) is a dense, greenish-yellow gas with
a distinctive irritating odor. The major
anthropogenic sources of chlorine emissions
include the chemical decomposition of
chlorofluorocarbons (CFCs) used as a
refrigerant and propellant in consumer goods,
the liquifaction of chlorine cell gas, the loading
and cleaning of tank cars, barges and cylinders,
dechlorination of spent brine solutions and
power or equipment failure. Due to the high
reactivity of Cl 2 with many substances, natural
emissions of Cl 2 gas are very rare. Volcanic
gases contain very small amounts of Cl 2. Low
concentrations of Cl 2 may, however, be formed
by atmospheric reactions.The use of propellants which do not
contain CFCs. Industrial emissions
can be controlled by the use of
scrubbing systems, i.e., water
scrubbers, alkali scrubbers and carbon
tetrachloride scrubbers.Since chlorine has strong oxidizing and bleaching
properties, it is extremely hazardous to all life
forms, as well as corrosive to metals and other
materials. Chlorine atoms can destroy ozoneC001_006_r03.indd 90C001_006_r03.indd 90 11/23/2005 9:42:39 AM11/23/2005 9: