The role of mass transfer in the kinetics of chemical oxidation of anthracine slurry to anthraquinone in a batch stirred tank reactor

The kinetics of chemical oxidation of anthracine powder by acidified dichromate in a batch agitated vessel stirred by a 45degrees four pitched blade turbine impeller was studied under different conditions. Variables studied were impeller rotation speed, solution physical properties and temperature. The rate of anthracine oxidation was found to increase with temperature according to the Arrhenius equation with an activation energy of 3.98 cal/mole. The rate of anthracine oxidation was found to increase with 0.56 power of impeller rotation speed. The value of the activation energy and the sensitivity of the rate of oxidation to stirring lend support to the diffusion-controlled nature of the reaction. The data were correlated by the equation: Sh = 0.5 (.) 10(-1) Sc-0.33 . Fr-0.33 Implication of the above equation for the operation of industrial reactors was noted.