Deagglomeration of High Purity Fine Alumina Powder via pH Control

  • Andanastuti Muchtar Department of Mechanical and Material Engineering, Universiti Kebangsaan Malaysia
  • Norazmira Wati Department of Mechanical and Material Engineering, Universiti Kebangsaan Malaysia
  • Nor Azri Jaafar Department of Mechanical and Material Engineering, Universiti Kebangsaan Malaysia
Keywords: colloidal processing, fine alumina powders, pH control, rheology, sintering characteristics, microstructure

Abstract

This paper presents results from a study on the effect of the pH of suspensions on the deagglomeration of a high-purity (99.99%), fine-grained alumina powder. The pH of the suspension was varied between pH 2 and 3. It is the aim of the study to determine the best pH for a successful dispersion of the alumina powders in the suspension. A series of rheological studies and analytical work under Scanning Electron Microscopy were conducted. It was found that the best pH was pH 2. Data obtained from rheological studies using a viscometer showed that the alumina suspension prepared at pH 2 was least viscous, which may be taken as a negative indicator of the presence of agglomerates. This hypothesis is validated by visual inspection using SEM. For the pH 2 samples, a successful removal of the agglomerates in the green compact has encouraged the sinterability of the samples and thus, resulted in an earlier sintering process at a low-firing temperature. In addition, the sintering characteristics and microstructures of the samples prepared with a pH 2 suspension are also presented.

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Published
2002-12-31
How to Cite
Muchtar, A., Wati, N., & Jaafar, N. A. (2002). Deagglomeration of High Purity Fine Alumina Powder via pH Control. ASEAN Journal of Chemical Engineering, 2(1), 55-60. Retrieved from https://dev.journal.ugm.ac.id/v3/AJChE/article/view/7527
Issue
Vol 2 No 1 (2002)
Section
Articles

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