(西安建筑科技大學(xué) 冶金工程學(xué)院，西安 710055)
摘 要: 選用過硫酸鹽+銀鹽作氧化劑，在超聲波作用下對硫化鎳礦進(jìn)行直接氧化浸出，研究攪拌速率、過硫酸鈉濃度、浸出溫度、銀鹽濃度及粒度對鎳浸出率的影響規(guī)律，探討氧化浸出反應(yīng)機(jī)理。結(jié)果表明：在一定范圍內(nèi)，在超聲波作用下攪拌速率或者粒度的變化對鎳浸出率影響不顯著；鎳浸出率隨Na2S2O8濃度的增大以及溫度的升高而增加，但是當(dāng)溫度高于70 ℃后，浸出率的增加不明顯；在浸出過程中起主導(dǎo)作用的是S2O82−，少量銀鹽的存在對浸出反應(yīng)有促進(jìn)作用。通過對該體系浸出過程動(dòng)力學(xué)參數(shù)的考察，發(fā)現(xiàn)其符合縮核模型，過程總體反應(yīng)速率受界面化學(xué)反應(yīng)控制，表觀活化能為39.67 kJ/mol，建立了浸出過程的宏觀動(dòng)力學(xué)方程。
關(guān)鍵字: 硫化鎳礦；氧化浸出；動(dòng)力學(xué)；表現(xiàn)活化能；超聲波；縮核模型；界面化學(xué)反應(yīng)
nickel sulfide concentrate
（School of Metallurgical Engineering, Xi’an University of Architecture and Technology, Xi’an 710055, China）
Abstract:The method of leaching nickel directly with oxidants of sulphate and silver salts with the assistance of ultrasonic was proposed. The influence of stirring speed, S2O82− concentration, leaching temperature, silver ion concentration and granularity on the leaching rate of nickel was investigated. The reaction mechanism of oxidizing leaching was explored. The results show that the influence of stirring speed or granularity on the leaching rate is not obvious in a certain range; with the increase of S2O82− concentration or leaching temperature, the leaching rate of nickel increases, whereas when the temperature is above 70 ℃, the increase of leaching rate is not obvious; S2O82− plays a dominant role in the oxidation action during the leaching process. The presence of a small amount of silver salt can promote the leaching reaction. Through investigating the dynamic parameters of the process, the dynamics in accordance with the shrinking core model is found. The overall reaction rate is controlled by interfacial chemical reaction with apparent activation energy of 39.67 kJ/mol. The macro-dynamic equations of the process are established.
Key words: nickel sulfide concentrate; oxidation leaching; dynamic; apparent activity energy; ultrasound; shrinking core model; interfacial chemical reaction
