Development and evaluation of a countercurrent parallel-plate membrane diffusion denuder for the removal of gas-phase compounds from vehicular emissions.
Diffusion denuders have been commonly used to remove trace gases from an aerosol (mixture of gases and particles), while allowing the particles to remain suspended in air. We present the design and evaluation of a high-flow (16.7 L min⁻¹) countercurrent parallel-plate membrane diffusion denuder that has high removal efficiencies for both non-reactive gases such as carbon monoxide (89%), as well as volatile organic compounds (80-85%) from an automobile exhaust. Particle losses were approximately 15% for particles around 100 nm in diameter. This denuder is suitable for toxicological tests involving both human and animal exposures to combustion aerosols. The denuder may also be used for other applications, for example, to reduce the effect of gas-phase sampling artifacts on particle composition.
Department of Environmental Health, Harvard School of Public Health, 401 Park Drive, Landmark Center West, Boston, MA 02215, USA. vpapapos@hsph.harvard.edu
Vasileios
V
Papapostolou
Joy E
JE
Lawrence
Stephen T
ST
Ferguson
Jack M
JM
Wolfson
Petros
P
Koutrakis
D000393:Air Pollutants / Q000737:chemistry*; D002248:Carbon Monoxide / Q000737:chemistry*; D004058:Diffusion; D004867:Equipment Design; D008567:Membranes, Artificial; D010316:Particle Size; D011138:Polytetrafluoroethylene; D016062:Porosity; D013193:Stainless Steel; D018675:Toxicity Tests / Q000295:instrumentation*; D001335:Vehicle Emissions; D055549:Volatile Organic Compounds / Q000737:chemistry*
D000393:Air Pollutants; D008567:Membranes, Artificial; D001335:Vehicle Emissions; D055549:Volatile Organic Compounds; D013193:Stainless Steel; D002248:Carbon Monoxide; D011138:Polytetrafluoroethylene