عنوان به زبان ديگر :
The Contribution of Molecular Diffusion in Silica Coating and Chemical Reaction in the Overall Rate of Reaction of Aluminum Hydroxide with Fluosilicic Acid
پديد آورندگان :
Bayat Mahmoud نويسنده , Taeb Abbas نويسنده , Rastegar Saeed نويسنده
چكيده لاتين :
The kinetic of the heterogeneous chemical reaction of aluminum hydroxide. and
fluosilicic acid was studied. It was found that the diffusion ofthe reactants through the porous silica
coating to the aluminum hydroxide surface and the interfacial chemical reaction between the
diffusing reactant and aluminum hydroxide platelets control the overall reaction rate. These two
phenomena were studied and their contributions to the overall reaction rate were derived using
experimental data. By combining these terms a relation for the overall reaction rate was obtained.
The activation energy ofthe chemical reaction was calculated to be 12 kcal/mol and the activation
energy ofthe diffusion into the silica coating was found as 28 kcal/mol. A numerical procedure was
adjusted to determine the variation of the specific surface area of un-reacted core, its average
particle size and the specific surface area for mass transfer