Personal monitoring method for nitrogen dioxide and sulfur dioxide with solid sorbent sampling and ion chromatographic determination

The Use of Passive Diffusion Tubes for Measuring Concentrations of Nitrogen Dioxide in Air

“…In an early study, uptake of NO 2 by TEA coated onto a molecular sieve was shown to lead to production of both NO − 2 and NO − 3 ions, especially at low relative humidities (58). Similar results were shown for TEA coated onto silica in Sep-pak cartridges, with 90% NO − 2 and 10% NO − 3 formed from NO 2 (59).…”

“…Subsequent studies showed that the humidity was important in determining the reaction pathway, with a higher fraction of NO 2 converted to NO − 2 at higher relative humidities (58). The decrease in NO − 2 production at low RH was ascribed to formation of different products (52).…”

Laboratory validation of a passive sampler for SO2 atmospheric monitoring

“…TEA solution was tested at different concentrations, based on former authors, 22,25,38,41,42 but satisfactory analytical results were found only for 1.0 x 10 -1 mol L -1 solution, whose maximum efficiency of SO 2 absorption was 88%. Moreover, TEA presents unsuitable behavior to be used in passive samplers: dependence on relative humidity, problems of sampler storage after exposure and low stability of TEA/SO 2 complex.…”

Método colorimétrico para determinação de dióxido de nitrogênio atmosférico com preconcentração em coluna de c-18

“…Porém a umidade é um inconveniente, já que pode gerar NO 14 . Para contornar este problema e melhorar a eficiência de coleta, as superfícies têm recebido um recobrimento de reagentes seletivos para o NO 2 , como a p-anisaldina 17 e, com maior freqüência a trietanolamina (TEA) [18][19][20][21][22][23] .…”