Abstract
Fundamental study to remove sulfur from PbS was performed by heating PbS under a stream of air at a given temperature between 973 K and 1273 K. Desulfurization ratio was evaluated by measuring the amount of SO2 generated by oxidation reaction and the residual products were analyzed by X-ray diffraction method.
The desulfurization ratio increased with increasing temperature and reached approximately 80 % at 1200 K after 7.2 ks under an air flow rate of 500ml/min. The residual products changed from PbSO4 to PbO through PbSO4·xPbO during heating, where X in PbSO4·xPbO increased with increasing temperature.
SiO2 was added to PbS to promote desulfurization ratio. Mixtures of PbS and SiO2 at various ratios were put under a stream of air at the same experimental condition. At 1073 K, SiO2 showed a remarkable effect on desulfurization at xsio2 < 0.5, where xsio2 denotes mole fraction of SiO2 in PbO-SiO2 system. At xsio2 = 0.3, the desulfurization ratio was approximately 80 % which is equal to the value of the case at 1173 K without SiO2.