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Published on: April 10, 2017
Characterization of concentrated colloidal ceramics suspension: a new approach
Bimal P Singh1, Ruben Menchavez, Masayoshi Fuji
1Ceramic Research Laboratory, Nagoya Institute of Technology, Asahigaoka 10-6-29, Tajimi, Gifu 507-0071, Japan. bpsingh99@yahoo.com
Journal of Colloid and Interface Science
|April 25, 2006
Summary
Capillary suction time (CST) effectively measures ceramic suspension dispersion. Optimal dispersion occurs at pH(iep), with stability correlating to zeta potential and solids loading.
Area of Science:
- Materials Science
- Colloid and Surface Chemistry
Background:
- Understanding the dispersion behavior of concentrated ceramic suspensions is crucial for controlling their properties and applications.
- Alumina (Al2O3) suspensions are widely used in ceramics, but their stability and processability depend heavily on dispersion characteristics.
Purpose of the Study:
- To investigate the dispersion behavior of concentrated alumina (Al2O3) suspensions using capillary suction time (CST).
- To evaluate the influence of solids concentration and dispersant (APC) on suspension stability.
- To establish CST as a quantitative method for characterizing ceramic suspensions.
Main Methods:
- Capillary suction time (CST) measurements were performed on Al2O3 suspensions at varying solids concentrations.
- Experiments were conducted with and without the addition of a dispersant (APC).
- pH-dependent behavior and dispersion ratio (DR) were analyzed.
Main Results:
- CST values were lowest at the isoelectric point of the particles (pHiep), indicating optimal dispersion.
- CST increased with higher solids concentration and deviations from pHiep, attributed to inter-particle repulsive forces.
- Dispersion ratio (DR) quantified dispersability, with values above unity indicating better dispersion.
Conclusions:
- The CST technique provides a practical and quantitative method for assessing the dispersion stability of concentrated ceramic suspensions.
- A correlation exists between CST, zeta potential, colloidal stability, and maximum solids loading.
- CST can be utilized as a diagnostic tool for optimizing ceramic suspension properties.
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