Measurement of nitrogen dioxide and nitrous acid using gas-permeable liquid core waveguides

Abstract

Nitrogen dioxide is an important atmospheric contaminant, classified as a criteria pollutant in the United States. It can be sensitively determined by the simple colorimetric Griess-Saltzmann method. This can constitute the basis of an inexpensive sensitive instrument based on gas-permeable liquid core waveguide tubes that allow long path absorbance measurement. Nitrous (HONO) acid is often present in the atmosphere along with NO 2 . Nitrous acid concentration can be significant relative to NO 2 , especially at night-time when photodecomposition of HONO is no longer operative. Griess-Saltzman chemistry cannot differentiate between HONO and NO 2 . In the present paper, we have explored the possibility of simultaneously determining both analytes by using more than one collector with dimensional differences. Presented results show that differences in either length or wall thickness can permit such differentiation.

A Micro-impinger Sampling Device for Determination of Atmospheric Nitrogen Dioxide

“…The reagent has been used since the 1960s in different analytical methods. Only over the last 30 years, several examples can be cited (Nagashima and Nakano, 1999;Ohyama et al, 2000;Milani et al, 2001;Izumi et al, 2015;Fàbrega et al, 2017). The Griess-Saltzman (GS) solution has been included as a recommended NO 2 chemical method in Methods of Air Sampling and Analysis (Method 406, James P. Lodge, Jr., 1989) a handbook for air pollution control and industrial hygiene and also as a standard test method for nitrogen dioxide content of the atmosphere, method ASTM D1607-91(2011) in American Society for Testing and Materials (ASTM D1607-91(2018)e1).…”

Micro gas analyzers for environmental and medical applications

“…Therefore, high sensitivity is obtained using absorbance methods even though they employ small optical devices such as a light emitting diode (LED) and a photodiode (PD). The long gas collection/absorbance cell tube was applied to the analysis of NO 2 and O 3 [27], Cl 2 , H 2 S, NO 2 and CO 2 [28], HONO and NO 2 [29], H 2 O 2 [30], and O 3 [31].…”

Colorimetric NOx sensor based on a porous glass-based NO2 sensing chip and a permanganate oxidizer

“…Several methods currently exist for the measurement of NOx [6]: absorption photometry based on chemical reactions [7][8][9][10][11], chemiluminescent techniques based on the reaction of NO with ozone (O 3 ), sensor-based techniques, physical measurements using IR or UV absorption, and fluorescent photometry applying the micro-TAS technique [12]. Of these, chemiluminescence is the most reliable technique and thus instruments based on this principle are widely employed in air quality monitoring by governmental organizations.…”