Adsorbing Filter Media for Carbon Mass Balance Measurements in Airborne Particles

IB-903D

E.O. Lawrence Berkeley National Laboratory

APPLICATION OF TECHNOLOGY:

• Carbon mass balance measurements in airborne particles
• Denuder substrates for all organic compounds
• Ambient air sampling for organic particulate matter
• Gas/particle partitioning data
• Indoor air sampling and air cleaning
• Air quality research studies
• EPA mandated air sampling

ADVANTAGES:

• Suitable for thermal analysis
• Trap organic compounds reversibly
• Simpler
• Cheaper
• Faster
• More accurate

ABSTRACT:

Lara Gundel of Berkeley Lab has developed new filter media that allow for carbon mass balance measurements in airborne particles. Currently, the only methods available for sampling total evolved carbon involve collection on polyurethane foam (PUF) cartridges or sorbent beds that must be extracted and analyzed for specific, semivolatile, organic compounds. As of yet, there is no method for quantitating the total organic material that evaporates from particles during filter-based sampling. Berkeley Lab's new filter media supplies an appropriate backup filter for a denuded adsorbing-filter system which can be analyzed for total organic carbon. When used as adsorbing backup filters, these media are efficient in capturing all organic compounds that evaporate from the front filter during sampling, and are suitable for thermal analysis. They can also be used as denuder substrates, in which case the media efficiently remove all gas phase organic compounds that would otherwise be collected by the adsorbing backup filter. Berkeley Lab's new adsorbent filter media trap organic compounds reversibly, and release them when heated or extracted. The media are suitable for analysis of evolved carbon at temperatures below 300 degrees Celsuis, corresponding to the semivolatile constituents that evaporate from particles.

This approach has the potential of providing (1) a low blank when analyzed by thermal analysis techniques, (2) an efficient yet compact and low pressure drop collection material, and (3) efficient recovery of evaporated organic particulate material. Berkeley Lab's new filter media allows thermal analysis, which is simpler, cheaper, and faster than extraction and analysis of PUF cartridges, and enables more accurate measurements of outgassing from unstable particles. This new filter media can be used for ambient air sampling for organic particulate matter, such as has been mandated for a national network by the US Environmental Protection Agency, and as is routinely needed for air quality research studies. It is useful for providing gas/particle partitioning data by identifying the source of evolved carbon as either gas or stable particles or outgassing. This technology can also be used for a variety of indoor air sampling and air cleaning applications.

STATUS: Available for licensing

REFERENCE NUMBER: IB-903D