Development of a Gas-Sampler Based on the Nebulizer-Denuder Method

• Published in: Bunseki kagaku Vol. 54; no. 12; pp. 1175 - 1182
• Main Authors: KUROSAWA, Kiyoko, TATENUMA, Katsuyoshi, MUTO, Manabu, ESUMI, Hiroyasu, KANDA, Yukio
• Format: Journal Article
• Language: English
• Published: Tokyo Japan Science and Technology Agency 01.12.2005
• ISSN: 0525-1931
• DOI: 10.2116/bunsekikagaku.54.1175

In order to measure a small amount of constituent in gaseous samples, such as measuring the causative substances of the sick-house syndrome, according to general solid-phase adsorption, complicated handling, such as solvent extraction, or concentration and heating desorption, are required. Consequently, we have developed a simple and highly accurate continuous gas sampler consisting of a denuder and a cross flow nebulizer. An absorbing solution and gaseous sample are simultaneously introduced to the nebulizer, and a droplet absorbent is then flowed in the inner wall of the denuder tube, while contacting with the gaseous sample. By optimizing the flow ratio between the gaseous sample and the absorbent, the targeted constituent in the gaseous sample is efficiently absorbed into the absorbent while flowing in the tube. By experiments being currently conducted, in the case of formaldehyde recovery under the condition of a gaseous sample flow rate of 2.0 l/min and an absorbent (purified water) flow rate of 0.1 ml/min (volume ratio of gaseous sample/absorbent = 20000 : 1), a recovery rate of 95% or more was stably and continuously obtained, and a concentration of less than 1/10 of the regulated formaldehyde concentration in a room can be analyzed without any extraction or concentration procedures. We will apply this simple gas sampler to practicable technologies, such as the recovery of other volatile organic compounds (VOC) constituents, an on-site sick-house monitoring system with a detective device, and cancer diagnosis using expiratory air.