Oxidation of zinc sulphide concentrate in a fluidised bed reactor - Part 2: The influence of experimental variables on the kinetics

The oxidation kinetics of a blend of zinc sulphide concentrates in a bench-scale fluidised bed reactor operated in batch regime was studied. The fractional conversion was determined by measuring the SO2 concentration in the exit gas using a chromatograph. The effects of the initial mass of the blend, airflow rate and temperature on fractional conversion were studied. The initial mass of the blend varied from 45 to 75 g, the airflow rate from 6 to 9 L/min and the temperature from 883 to 1213 K. The time for complete conversion was affected by the molar ratio of O2 to S fed into the reactor and by temperature. The oxidation reaction was controlled by surface chemical reaction of the unreacted core of the particles. The value of the activation energy, 87 kJ/mole, supports the contention that the reaction was chemically controlled.