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›› 2005, Vol. 5 ›› Issue (3): 289-294.

• 过程与工艺 • 上一篇    下一篇

高稳定性碱性硫脲体系对不同类型金矿的适应性

郑粟,王云燕,柴立元,张晓飞   

  1. 中南大学冶金科学与工程学院
  • 出版日期:2005-06-20 发布日期:2005-06-20

Adaptability of Gold Leaching from Different Ores in Highly Stable Alkaline Thiourea Solutions

ZHENG Su,WANG Yun-yan,CHAI Li-yuan,ZHANG Xiao-fei   

  1. College of Metallurgical Science and Engineering, Central South University
  • Online:2005-06-20 Published:2005-06-20

摘要: 为考察碱性硫脲体系对不同类型金矿浸出的适应性,选用理化性质不同的6种含金物料,分析了其化学组成及矿物物相,并对其浸出行为进行了研究. 结果表明,稳定剂Na2SO3和Na2SiO3大大降低了碱性硫脲的分解率,随稳定剂浓度的增大,硫脲分解率逐渐降低;而且Na2SiO3对碱性硫脲的稳定效果明显优于Na2SO3,当Na2SiO3浓度为0.3 mol/L时,硫脲的分解率由72.5%降至33.8%. 铁氰化钾为适合碱性硫脲浸金的温和氧化剂. 碱性硫脲体系中金矿物浸出前后物相基本无变化. 所选择的金矿物中均含有大量耗碱物质,使溶液的pH值由12.5很快降至中性,但稳定剂Na2SiO3能维持体系的pH值在12左右,有利于浸出过程的进行. 碱性硫脲体系中伴生金属浸出率小于0.1%,浸金具有显著的选择性. 碱性硫脲体系适合浸出经预处理的物相主要为SiO2的氧化矿,浸金率高达82.68%,为碱性硫脲成功应用于黄金工业生产提供了一定的理论依据.

关键词: 碱性硫脲, 硫化金精矿, 金焙砂, 浸金率

Abstract: In order to examine the flexibility of leaching different gold ores in alkaline thiourea system, six kinds of gold concentrates and calcines with different physical and chemical properties were chosen as objects, their chemical components and phases were analyzed, and the leaching behaviours were also investigated. The results indicated that stablizing reagents Na2SO3 and Na2SiO3 decreased the decomposition rate of alkaline thiourea solution greatly. However the stable effect of Na2SiO3 on alkaline thiourea was obviously better than that of Na2SO3 as well, and the decomposition rate of alkaline thiourea reduced from 72.5% to 33.8% with adding 0.3 mol/L Na2SiO3. K3Fe(CN)6 was the soft oxidizing reagent being suitable for alkaline thiourea system. The phases of gold ores were almost not changed before and after leaching in alkaline thiourea solution. There exist a large number of substances consuming alkali in the gold ores. During the leaching process, pH of the system dropped from 12.5 to 7.0 quickly, while the stablizing reagent Na2SiO3 could maintain pH of the system at about 12, which was propitious to the leaching process. The leaching rates of the coexisting metals in gold ores were less than 0.1% in alkaline thiourea system, which indicated that gold leaching in alkaline thiourea retained excellent selectivity. The alkaline thiourea system was suitable for leaching the pretreated oxidized gold ores in which the main phase was SiO2. The gold leaching rate reaching up to 82.68% suggests promising potential in commercial gold leaching processes.

Key words: alkaline thiourea, gold sulphide concentrate, gold calcine, gold leaching rate