| Yangjiazhangzi molybdenum ore is the largest molybdenum ore production base in the period of China founding initial.After decades of construction and development, it has possessed the capacity of prospecting, mining, mineral processing and metallurgy. At the same time, there is about a hundred million ton of mine tailings left. Because it is a kind of refractory mineral, adopting the traditional physical technique for ore-dressing is difficult to enrich the value elements from the ores. The traditional pyro-metallurgy could not yet achieve the ideal purpose of recycling molybdenum.On this condition,a new produetive process of molybdenum from mine tailings had been studied in this thesis. The process mainly consisted of Na2CO3-roasting, leac hing, and depositing molybdenum three parts. At first, oxygenize the molybdenu m ore by using the method of oxidizing roast to make the Mo and other metals sulphide conversing oxidate. Then the oxidate of Mo and S react with Na2CO3, some water-sol uble product is obtained. Nextly, using NaOH to leaching molybdenum selectively at the condition of inletting O2. Thirdly, carbonation is applied to recycle Na2CO3, and pH value of leaching water fall down; Changing the pH value of leaching water until it comes to 2-3. After roasting the deposition, molybdenum oxidate is obtained.This thesis researched the influence of roast temperature,addition Na2CO3 of roast time to the leaching rate roasting of Mo ore through a single factor experiment. Resul ts show that the best craft parameters are:roast temperature is 600℃,roast time is 3 h, and addition of Na2CO3(2 times).The effect for the extraction ratio of Mo minerals of leaching temperature,leaching times,sodium hydroxide quantity is investigated.The experimenial results show that the optimal technological parameters of leach are:NaOH(2mol/L),leaching time was 2h, leaching temperature was 90℃, the ratio of liquor to solid was 5:1.Under the optimal technological parameters,leaching ratio could reach 98.43%.
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