Investigation of Different Stages of Aluminum Fluoride Crystal Growth

Document Type: Research Article

Authors

1 Faculty of Chemical Engineering, Iran University of Science and Technology, P.O.Box 16765-163 , Tehran , I.R.IRAN

2 Faculty of Polymer Engineering,Amirkabir University of Technology, P.O.Box 15875-4413, Tehran, I.R.IRAN

Abstract

Crystallization of Aluminum fluoride at atmospheric pressure has been considered. Structure, size and shape of crystals formed during the crystallization process have been investigated. By applying the direct analysis method for the existed aluminum in solution, the aluminum fluoride nucleation process has been detected as a concentration valley at the outset of crystallization process. The linear rate of growth of aluminum fluoride crystals has been measured by taking SEM micrographs from crystals during crystallization process. The rate of crystal growth in longitudinal direction is about 10-9 m/s and nearly six times more than the rate of crystal growth in side direction. It is indicated that the aluminum fluoride nucleation process is repeated after completion of growth of initial crystals.

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