The kinetic of the heterogeneous chemical reaction of aluminum hydroxide and fluosilicic acid was studied. It was found that the diffusion of the 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...

The effect of mechanical activation on structural changes and kinetics of carbothermic reduction of hematite with graphite was studied in this research. Hematite powder mixture with graphite (with stoichiometry ratio C/O=1) was milled for the time periods of zero to 50 hours, and the structural changes were studied using X ray diffraction (XRD). The effect of mechanical activation on the kineti...

Spherical pellets of antimony sulphide were dissolved in 1 molar sodium hydroxide solutions at different temperatures. It was found that the shrinking core with ash layer model could satisfactorily explain the dissolution process. Using this model it was found that initially the rate controlling step is a chemical reaction with activation energy of 10.2 kJ/mol. As the ash layer builds up, diffu...

Background & Aims of the Study: A high nitrate and arsenic concentration in water resources represent a potential risk to the environment and public health. The present work improved a chemo-physically modified activated carbon derived from walnut shells as an adsorbent to improve nitrate and arsenic removal ability from water. Materials & ...