Measurement of atmospheric formaldehyde using a drop collector and in-situ colorimetry
Contribuinte(s) |
Universidade Estadual Paulista (UNESP) |
---|---|
Data(s) |
20/05/2014
20/05/2014
01/01/1997
|
Resumo |
A sensitive and affordable approach is described for the in-situ measurement of ambient formaldehyde. Air is sampled around a 100 microliter aqueous drop containing 3-methyl-2-benzothiazoline hydrazone. After a desired period of sampling (typ. 5 min) and a waiting period of 10 min for the reaction to be completed, a second reagent (FeCl3) is added to the drop by means of a conjoined conduit. A blue product is formed and is read after an additional 10 min of reaction by a fiber-optic/light emitting diode based photodetector. A fresh drop is then formed and the process begins anew. As demonstrated here, the limit of detection is similar to 6.25 mu g m(-3) HCHO but can be significantly improved by using longer sampling times and a sampling rate higher than 100 mi min(-1) used in most of this work. This is the first example of a chromogenic drop sensor that utilizes sequential reagent addition. |
Formato |
201-213 |
Identificador |
http://dx.doi.org/10.1080/03067319708028363 International Journal of Environmental Analytical Chemistry. Reading: Gordon Breach Sci Publ Ltd, v. 66, n. 3, p. 201-213, 1997. 0306-7319 http://hdl.handle.net/11449/38561 10.1080/03067319708028363 WOS:000072293600005 |
Idioma(s) |
eng |
Publicador |
Gordon Breach Sci Publ Ltd |
Relação |
International Journal of Environmental Analytical Chemistry |
Direitos |
closedAccess |
Palavras-Chave | #formaldehyde #colorimetry #drop sensor #light emitting diode |
Tipo |
info:eu-repo/semantics/article |