摘要
焙烧氰化尾渣处置是目前制约黄金冶炼工业可持续发展的瓶颈,为了提高金的回收率和实现尾渣中铁的高附价值利用,在草酸(H_(2)C_(2)O_(4))、草酸-草酸铵(H_(2)C_(2)O_(4)-(NH_(4))2C_(2)O_(4))浸出焙烧氰化尾渣中赤铁矿试验结果的基础上,对H_(2)C_(2)O_(4)-(NH_(4))2C_(2)O_(4)浸出赤铁矿的机理以及浸出动力学进行研究,主要考察浸出温度、H_(2)C_(2)O_(4)与(NH_(4))2C_(2)O_(4)物质的量之比n(H_(2)C_(2)O_(4))/n((NH_(4))2C_(2)O_(4))以及C_(2)O_(4)^(2-)总浓度c(C_(2)O_(4)^(2-))TOT对铁的浸出率的影响。结果表明,适当降低n(H_(2)C_(2)O_(4))/n((NH_(4))2C_(2)O_(4))、提高c(C_(2)O_(4)^(2-))TOT和浸出温度,可提高铁的浸出率,缩短赤铁矿达到浸出平衡的时间。H_(2)C_(2)O_(4)-(NH_(4))2C_(2)O_(4)浸出赤铁矿的反应表观活化能为41.72 kJ/mol,浸出反应受界面化学反应-内扩散混合控制。在n(H_(2)C_(2)O_(4))/n((NH_(4))2C_(2)O_(4))=1和n(C_(2)O_(4)^(2-))TOT/n(Fe^(3+))TOT≥3时,浸出液中的Fe3+全部以Fe(C_(2)O_(4))_(3)3-形式存在,通过对浸出液进行蒸发、浓缩、冷却、结晶,制备出用途较为广泛的(NH_(4))3Fe(C_(2)O_(4))_(3)·3H_(2)O,为氰化尾渣中巨量铁资源的综合利用提供了新途径。研究结果对黄金工业的可持续发展具有重要意义。
At present,the disposal of the cyanide tailings is the bottleneck restricting the sustainable development of gold smelting industry.In order to improve the recovery rate of gold and realize the high value-added utilization of iron in tailings,based on the experimental results of leaching hematite from the roasted cyanide tailings by H_(2)C_(2)O_(4) and H_(2)C_(2)O_(4)-(NH_(4))2C_(2)O_(4),mechanism and kinetics of leaching hematite by H_(2)C_(2)O_(4)-(NH_(4))_(2)C_(2)O_(4) were studied,and the effects of leaching temperature,molar ratio n(H_(2)C_(2)O_(4))/n(NH)_(2)C_(2)O_(4) and total concentration c(C_(2)O_(2)-)roT on the leaching rate of iron were mainly investigated.The results reveal that properly reducing n(H_(2)C_(2)O_(4))/n((NH_(4))_(2)C_(2)O_(4),increasing leaching temperature and c(C_(2)O_(2)-)roT can improve leaching rate of iron and shorten the time of leaching hematite to reach equilibrium.The apparent activation energy of leaching hematite reaction by H_(2)C_(2)O_(4)-(NH_(4))2C_(2)O_(4) is 41.72 kJ/mol,and the leaching reaction is controlled by interfacial chemical re-action and internal diffusion.At n(H_(2)C_(2)O_(4))/n(NH_(4))_(2)C_(2)O=1 and n(C_(2)O_(2)-)Tor/n(Fe^(3+))Tor)≥3,Fe^(3+) in the leaching solution exists in the form of Fe(C_(2)O_(4))_(3)^(3-).Through evaporation,concentration,cooling and crystallization of the leaching solution,the widely used(NH_(4)),Fe(C_(2)O_(4))_(3)·3H_(2)O is prepared,it provides a new way for the com-prehensive utilization of huge iron resources in cyanide tailings,and the research results are of great significance to the sustainable development of gold industry.
作者
党晓娥
李康瑞
王碧侠
李林波
DANG Xiaoe;LI Kangrui;VWANG Bixia;LI Linbo(l.College of Metallurgical Engineering,Xi'an University of Architecture and Technology,Xi'an 710055,Shaanxi,China;Key Laboratory for Gold and Resources of Shaanxi,Xi'an 710055,Shaanxi,China)
出处
《中国冶金》
CAS
CSCD
北大核心
2024年第8期117-127,共11页
China Metallurgy
基金
国家自然科学基金资助项目(51974221)。
关键词
焙烧氰化尾渣
赤铁矿
草酸-草酸铵
浸出
动力学
roasted cyanide tailings
hematite
H_(2)C_(2)O_(4)-(NH_(4))_(2)C_(2)O_(4)
leaching
kinetics
