Molybdenite Ore And Manganese Dioxide To Roasted New Technology Research

In view of the existing problems for roasting process of molybdenite, such as pollution of sulphur dioxide, low metal recovery ratio, great energy consumption, etc. the new roasting process of molybdenite mixed with manganese dioxide was put forward in this paper. The experiments on the roasting conditions of molybdenite mixed with manganese dioxide, separation of molybdenum and manganese, and synthesis of manganese dioxide with manganese sulfate, were carried out.The results showed that the decompound ratio of molybdenum disulfide and ratio of sulfur fixation could reach 99.5% and 92% respectively when the reactant ratio n(MnO₂)/n(MoS₂) was 3, reaction temperature was 450℃ and 550℃, reaction time was all 2h, and air flow was 15-20ml/min. The calcine were leached by sulfuric acid when the temperature was 30℃, and the leaching ratio of molybdenum and manganese could reach 99% and 92% respectively. The molybdenum and manganese in the leaching solution were separated by solvent extraction. The composition of extractant was 20% N235, 10% sec-octyl alcohol and 70% sulphonating kerosene. The extraction ratio of molybdenum could reach 99% when the number of extraction stages was 3 and the phase ratio (W/O)was 2:1. The manganese sulfate in the raffinate was recovered by alkaline oxidation process. Using ferrous sulfate as the catalyst, the conversion ratio of manganese dioxide was 84%, the content of manganese dioxide was 90%, which could reach the requirement of circle utilization.The roasting system of molybdenite mixed with manganese dioxide was studied by thermodynamic calculation. The reation mechanism and character of the product were investigated by thermogravimetric analysis, x-ray diffraction (XRD) and scanning electron microscope (SEM). The results showed that in the roasting process of the molybdenite, the manganese dioxide could not only have good function of sulfur fixation, but also lower roasting temperature obviously and promote the oxidation decompound of molybdenum disulfide. The process of roasting molybdenite mixed with manganese dioxide was a new process ofchemical engineering and metallurgy of resources utilization and energy saving, and had good prospect of application.