Multisorbent tubes for collecting volatile organic compounds in spacecraft air.
AIHAJ
; 61(1): 69-75, 2000.
Article
en En
| MEDLINE
| ID: mdl-10772617
ABSTRACT
The sampling capability of Tenax-TA tubes, used in the National Aeronautics and Space Administration's solid sorbent air sampler to trap and concentrate contaminants from air aboard spacecraft, was improved by incorporating two sorbents within the tubes. Existing tubes containing only Tenax-TA allowed highly volatile compounds to "break through" during collection of a 1.5 L air sample. First the carbon molecular sieve-type sorbents Carboxen 569 and Carbosieve S-III were tested for their ability to quantitatively trap the highly volatile compounds. Breakthrough volumes were determined with the direct method, whereby low ppm levels of methanol or Freon 12 in nitrogen were flowed through the sorbent tubes at 30 mL/min, and breakthrough was detected by gas chromatography. Breakthrough volumes for methanol were about 9 L/g on Carboxen 569 and 11 L/g on Carbosieve S-III; breakthrough volumes for Freon 12 were about 7 L/g on Carboxen 569 and > 26 L/g on Carbosieve S-III. Next, dual-bed tubes containing either Tenax-TA/Carbosieve S-III, Tenax-TA/Carboxen 569, or Carbotrap/Carboxen 569 to a 10-component gas mixture were exposed, in dry and in humidified air (50% relative humidity), and percentage recoveries of each compound were determined. The Tenax-TA/Carboxen 569 combination gave the best overall recoveries (75-114% for the 10 compounds). Acetaldehyde had the lowest recovery (75%) of the 10 compounds, but this value was still an improvement over either the other two sorbent combinations or the original single-sorbent tubes.
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Bases de datos:
MEDLINE
Asunto principal:
Compuestos Orgánicos
/
Polímeros
/
Monitoreo del Ambiente
/
Exposición Profesional
/
Nave Espacial
/
Contaminantes Ocupacionales del Aire
Límite:
Humans
País/Región como asunto:
America do norte
Idioma:
En
Revista:
AIHAJ
Asunto de la revista:
MEDICINA OCUPACIONAL
Año:
2000
Tipo del documento:
Article
País de afiliación:
Estados Unidos