Abstract:
This thesis describes the kinetic study of the dehydroxylation of crocidolite. The reaction studied can be represented by the idealized equation:
The reaction was studied under vacuum conditions and followed primarily by a weight loss method. The experimental results have been compared with theoretical models for solid state reactions. The results of the dehydroxylation can be explained over the complete reaction range by a diffusion controlled mechanism. It is postulated that oxygen ions are the diffusing species and this postulation agrees with previous x-ray studies and activation energies of diffusion of oxygen in an oxygen lattice. It is shown that the particle controlling diffusion has a radius of less than 30 microns, and it is assumed that these particles are the individual fibres. The enthalpy of activation for the dehydroxylation has been determined, 46 ± 3 k cal./mole., and the entropy of activation is shown to lie in the range 2-6 cal./deg./mole.