钨离子交换工艺中钨锡分离新工艺(Ⅲ)——钨精矿的焙烧预处理研究

Study on the Influence of Roasting Pretreatment on the Leaching Ratio of Stannum in Tungsten Ion-Exchange Technology

在分析SnO2和Cu2FeSnS4碱浸出热力学行为差异的基础上,研究了钨精矿焙烧预处理对锡浸出率的影响。研究表明,苛性钠浸出钨精矿时,SnO2极难浸出,浸出率接近为零,而Cu2FeSnS4的浸出率则高得多,在一般浸出条件下,可高达40%～50%。钨精矿经过氧化焙烧后,可明显降低锡的浸出率,在焙烧温度为700～800℃、焙烧时间为2 h工艺条件下,Cu2FeSnS4所含硫化状态的锡就可完全转化为SnO2。锡的浸出率由5.96%下降至1.05%。

Based on the analysis and investigation of the thermodynamic differences of SnO2 and Cu2FeSnS4 in caustic soda leaching, the influence of roasting pretreatment on the leaching ratio of stannum was studied. The results show that the leaching ratio of SnO2 is very low while that of Cu2FeSnS4 is far higher up to 40 %-50 % in caustic soda leaching procedure. The leaching ratio of stannum reduced greatly when tungsten mine was roasted. When the baking temperature is 700-800 ℃, baking time is 2 hours, the sulfurized stannum of Cu2FeSnS4 can be all transferred into SnO2, and the leaching ratio of stannum was reduced from 596 % to 10.5%