AN EVALUATION OF INTEGRATING TECHNIQUES FOR MEASURING ATMOSPHERIC NITROGEN-DIOXIDE

Citation
Kj. Hedley et al., AN EVALUATION OF INTEGRATING TECHNIQUES FOR MEASURING ATMOSPHERIC NITROGEN-DIOXIDE, International journal of environmental analytical chemistry, 54(3), 1994, pp. 167-181
Citations number
31
Categorie Soggetti
Environmental Sciences","Chemistry Analytical
ISSN journal
03067319
Volume
54
Issue
3
Year of publication
1994
Pages
167 - 181
Database
ISI
SICI code
0306-7319(1994)54:3<167:AEOITF>2.0.ZU;2-Y
Abstract
Two integrating techniques for measuring ambient NO2 were evaluated. B oth techniques involved quantitative collection of NO2 in a reagent co ated cartridge, specifically triethanolamine (TEA)-coated silica gel a nd diphenyl-amine (DPA)-coated Florisil. The evaluation of these techn iques consisted of laboratory and field studies. The laboratory studie s of the TEA method indicated collection and reaction efficiencies of 100 and 90%, respectively. A positive interference occurred when O3 an d NO were passed through the cartridge simultaneously. PAN was found t o produce a 67% positive interference. The ambient concentrations dete rmined using the TEA method were approximately a factor of two higher than those determined using TDLAS. For the DPA method the collection a nd reaction efficiencies were determined to be 100 and 64%, respective ly. O3 produced a negative interference by reacting with the NO2-DPA p roducts. PAN produced a 42% positive interference. A regression of the DPA versus TDLAS determined ambient NO2 concentrations yielded a slop e of .91+/-.08 (r2=0.990.). Neither method was found suitable for netw ork use in its present form.