Growth and dissolution kinetics of aluminium fluoride trihydrate crystals

• Published in: Journal of crystal growth Vol. 69; no. 2; pp. 213 - 230
• Main Authors: Nielsen, Arne Erik, Altintas, Nilsen Dizdar
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.01.1984; Elsevier
• Subjects: Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Materials science; Methods of crystal growth; physics of crystal growth; Physics; Theory and models of crystal growth; physics of crystal growth, crystal morphology and orientation; Crystal growth; Temperature; Aluminium Fluorides Hydrates; Inverse crystal growth; Supersaturation; Kinetics; Aqueous solution; Experimental study; Dissolution; Growth from solution; Inorganic compound
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/0022-0248(84)90326-9

The rates of growth and dissolution of aluminium fluoride trihydrate crystals, AlF 3·3H 2O, in aqueous solution were measured as a function of the saturation ratio S = C C s (0<S<6) and of the temperature (30<=t<=85°C). Both growth and dissolution follow parabolic rate laws. The growth rates measured can be quantitatively accounted for by assuming that the rate determining step is the integration jump of the growth units into lattice positions at kinks, the rate of this elementary step being that of dissociation of a water molecule or a fluoride ion from the inner coordination sphere of the aluminium ion. The dissolution rate may have a similar mechanism.