钨矿物原料NaOH分解过程中抑制杂质的研究

Studies on the Inhibition of Impurities in Caustic Decomposition of Tungsten Concentrates

从理论上较全面地研究了钨矿物原料在NaOH分解过程中直接用白钨矿及其分解产物Ca(OH) 2 作为抑制剂 ,抑制磷、砷、硅等杂质浸出的可能性及生成物的形态。进而通过实验证明在有白钨矿存在的条件下 ,分解所得的粗Na2 WO4 溶液中砷、硅的含量均比经典法低一个数量级 ,接近经典法净化以后的水平。

The Inhibition of impurities of As,P,Si and Sn in the caustic decomposition of tungsten concentrates was studied.It indicated that in the presence of scheelite (CaWO 4) and Ca(OH) 2,during caustic decomposition of scheelite with NaOH,impurities,such as As,P,Si,will be more completely inhibited in the cake in the forms of NaCaAsO 4,Ca 3(AsO 4) 2,Ca 3(PO 4) 2,Ca 5(PO 4) 3(OH),CaSiO 3 and CaSnO 3.It has been proved in laboratory experiment and industrial practice that the content of As and Si in the Na 2WO 4 solution from caustic decomposition of scheelite and wolframite mixed concentrates is only 20%～30% of that from caustic decomposition of wolframite concentrates with the same contents of WO 3 and impurities. [