Direct Measurement of Phase Association in Aerosol Particles by High-Throughput Automated SEM/EDX

ANNETTE KOLODZIE (1), Herman Lemmens (2)

(1) FEI Company, USA, (2) FEI Company, Netherlands

     Abstract Number: 711
     Last modified: May 14, 2010

Abstract
Automated Mineralogy is a new technology that addresses the need for
reliable sample analysis and high throughput results in responding to
intractable environmental problems. Automated Mineralogy is an ultra fast
method of obtaining repeatable and statistically robust quantitative data
pertaining to risk assessment, remediation, long-term monitoring, and
restoration and reclamation efforts at potential and known contamination
sites.

The automation and integration of electron beam technology (Scanning
Electron Microscope) with Energy Dispersive X-ray analysis (EDX) has proven to be
an invaluable tool for high-throughput particle characterization in mineral
processing applications in the mining industry. In this paper, we report how
the same principles of particle analysis can be applied to the mineralogical
and textural analysis of natural and man-made airborne particles.

It is now possible to routinely sample and analyze environmentally important
materials and fully characterize their mineralogy and textures, including
mineral associations, particle size, particle shape, grain size and shape,
porosity, and degree of aggregation. These data are collected on a particle-
by-particle basis through revolutionary image analysis software which allows
the analyst to quantify environmentally important parameters and plot these
in the form of images, graphs, and tables, in turn providing information that
was previously immeasurable.

Examples will be presented of Automated Mineralogy being used to
characterize fly ash particles in cases in which phase determination is
complicated by the amorphous nature of the different phases. Traditional X-
ray diffraction techniques can only classify these particles as amorphous,
whereas EDX provides chemical classification. Results from application of
the technique to airborne particles from the center of a small
western European city and particles released in a welding shop will also be
shown.