Formation Kinetics of Calcium Aluminates |
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| Authors: | Vipin K Singh Mohammad M Ali Upendra K Mandal |
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| Affiliation: | Department of Ceramic Engineering, Institute of Technology, Banaras Hindu University, Varanasi-221005, India. |
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| Abstract: | The kinetics of formation of calcium aluminates was studied by firing the reaction mixes in the temperature range 12000° to 1460°C for reaction times from 15 to 360 min. Phases formed were determined by taking X-ray diffractograms of the samples. It was observed that all stable calcium aluminates were formed and that monocalcium aluminate (CA) grew with calcium dialuminate (CA2) in a 1:2 reaction mix of CaO and Al2O3. CA reacted further with Al2O3 to form CA2. The formation of CA2 obeyed the rate law equation 1 - (1 - x )1/3= Kt / r 2. The activation energy for the system (140 kJ·mol?1 (33.4 kcal · mol?1)) was determined by the Arrhenius equation. |
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| Keywords: | cements aluminates kinetics formation calcium |
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