ABSTRACT From the background of poor responses of metallic particles in printed circuit board
comminution fines to chemical conditioning froth flotation schemes, contrary to expectations
based on native metal flotation, surface studies were carried out on samples of these metallic
particles in quest for the probable causatives. Auger electron spectroscopy combined with
argon beam depth profiling was employed in studying the surface make-up of the metal
particles. The composition profiles down to 340 nm surface depth obtained showed that the
supposed metallic particles consist of organics, oxides, and various trace alloys different
from the bulk material of the particles. The profiles reveal the peculiar surfaces of the
particles and the matrix from which the particles were liberated. The study provides insight
for better appraisal of the flotation system the sample presents. Implementing chemical
conditioning flotation scheme on this sample must carefully consider the peculiar surface
make up in contrast to native metal occurrences.
Cite this paper
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