Surface Characterization of Metallic Particles in Printed Circuit Board Comminution Fines and the Processing Implication

Iyiola Olatunji Ogunniyi, M. K. G. Vermaak, Dick Groot

Materials Science and Metallurgical Engineering, University of Pretoria, South Africa.
Metallurgical and Materials Engineering, Federal University of Technology, Akure, Nigeria.

DOI: 10.4236/jmmce.2012.116045                

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.

Keywords

surface characterization, metallic particles, auger electron spectroscopy, printed circuit board, froth flotation.

Conflicts of Interest

The authors declare no conflicts of interest.

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