Microcharacterization of trace elemental distributions within individual coal combustion particles using secondary ion mass spectrometry and digital imaging

Journal Article · Tue Sep 01 00:00:00 EDT 1987 · Anal. Chem.; (United States)

DOI:https://doi.org/10.1021/ac00144a003· OSTI ID:6316009

Cox, III, X B; Bryan, S R; Linton, R W

Secondary ion image depth profiling is developed for application to the chemical characterization of individual micrometer-sized particles, specifically coal combustion fly ash collected by cascade impaction. A digital imaging system interfaced to a Cameca IMS-3F ion microscope permits the simultaneous acquisition of spatially resolved mass spectral data for a number of single particles. Small regions within each particle are chosen for computer-reconstructed local area depth profiles to minimize complications of particle geometry on sputter rate and useful ion yield. Sputtering rates are calibrated by use of SiO/sub 2/ standards and correlative SEM observation of the sputtered particles. Ion intensities averaged over groups of particles are related to concentrations by use of NBS standard fly ash samples. Substantial differences are often found in the relative concentrations and/or depth profiles of selected elements (Ba, Pb, Si, Th, Ti, U) from particle to particle. The technique is highly sensitive to trace elements within microvolumes. For example, the estimated U detection limit corresponds to approximately 10/sup 4/ atoms in an analytical volume of 0.1 ..mu..m/sup 3/ within a 20-..mu..m/sup 3/ single particle.

• Research Organization: Univ. of North Carolina, Chapel Hill
• OSTI ID: 6316009
• Journal Information: Anal. Chem.; (United States), Vol. 59:17
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
BARIUM
ION MICROPROBE ANALYSIS
MASS SPECTROSCOPY
FLY ASH
QUANTITATIVE CHEMICAL ANALYSIS
LEAD
SILICON
THORIUM
TITANIUM
URANIUM
COAL
COMBUSTION
DIGITAL SYSTEMS
EXPERIMENTAL DATA
IMAGE PROCESSING
PARTICLE SIZE
TRACE AMOUNTS
ACTINIDES
AEROSOL WASTES
ALKALINE EARTH METALS
ASHES
CARBONACEOUS MATERIALS
CHEMICAL ANALYSIS
CHEMICAL REACTIONS
DATA
ELEMENTS
ENERGY SOURCES
FOSSIL FUELS
FUELS
INFORMATION
MATERIALS
METALS
MICROANALYSIS
NONDESTRUCTIVE ANALYSIS
NUMERICAL DATA
OXIDATION
PROCESSING
RESIDUES
SEMIMETALS
SIZE
SPECTROSCOPY
THERMOCHEMICAL PROCESSES
TRANSITION ELEMENTS
WASTES
010600* - Coal
Lignite
& Peat- Properties & Composition
010900 - Coal
Lignite
& Peat- Environmental Aspects
400101 - Activation
Nuclear Reaction
Radiometric & Radiochemical Procedures