Processing technologies for gold-telluride ores

Gold telluride ores are important gold refractory ores due to the presence of sulfides and other gangue materials. The classification and main physical properties of gold telluride ores were described, and possible treatment methods including flotation, leaching, and oxidation were reviewed. The results show that flotation procedures are much easier for gold tellurides compared to other refractory gold-bearing ores. For the conventional cyanide leaching process, pretreatment such as oxidation is required to achieve high gold recovery. Roasting is a relatively simple but not environment-friendly method; bio-oxidation technology seems to be more suitable for the oxidation of flotation concentrate. Other treatment methods involve cyanide leaching, thiourea leaching, ammoniacal thiosulfate leaching, carbon-in-pulp, and resin-in-pulp, all of which are less commonly utilized.     

含金矿物的氰化浸取动力学

筛选了一种能强化金浸取反应速率的添加剂——间硝基苯磺酸钠(MS),并进行了浸取反应过程的动力学研究。讨论了MS和氰化钠浓度、温度、搅拌强度及矿物粒度等因素对浸取反应的影响。MS通过改变阴极反应体系强化了金的氰化浸取反应速率,且对浸取液中氰化物无破坏作用。采用收缩未反应芯模型较好地描述了金的浸取过程,金浸取的动力学过程受扩散控制。同时导出了宏观动力学方程。用黄铁矿焙渣在串联式池浸装置中进行工业化模拟试验的结果表明,含MS的浸取液,浸取金含量仅为0.94g/t的矿渣,具有较力满意的结果。     

A review of gold extraction using noncyanide lixiviants: Fundamentals,advancements, and challenges toward alkaline sulfur-containing leaching agents

Alkaline sulfur-containing lixiviants, including thiosulfate, polysulfides, and alkaline sulfide solutions, stand out as a promising class of alternatives to cyanide because of their low toxicity, high efficiency, and strong adaptability. In this paper, we summarized the research progress and remaining challenges in gold extraction using these noncyanide reagents. After a brief introduction to the preparation method, the transformation process of various sulfur-containing species in alkaline solutions was discussed. Thereafter, some insights into the mechanism of gold leaching in alkaline sulfur-containing solutions were presented from different aspects, including thermodynamics analysis, electrochemical dissolution, and leaching kinetics. Moreover, recent progress in in-situ generation of sulfur-containing anions from gold-bearing sulfide minerals was outlined as well. Gold passivation caused by sulfur species was discussed in particular because it is considered the greatest challenge facing sulfur-containing leaching systems. Alkaline sulfur-containing lixiviants are expected to serve as alternatives in industrial applications of gold extraction, particularly for refractory gold ores containing copper and carbonaceous matter.     

用硫酸氧化预处理从难处理金矿中提金的无害化工艺研究

探讨了硫酸作为氧化剂分解含砷难处理金矿的技术可行性,实验结果表明硫酸可以有效地氧化砷黄铁矿而实现金的单体解离,适宜的分解条件为：硫酸与矿粉重量比为３,采用机械搅拌,反应温度２４０～２６０℃,分解时间２～３ｈ,分解渣采用硫脲浸出时浸金率高于９５％浸金条件为：硫脲浓度１％,三价铁作氧化剂,氧化剂与络合剂比值为０．０４～０．０６,浸出时间６ｈ图１,表６,参８     

Recovery of gold from refractory gold ores: Effect of pyrite on the stability of the thiourea leaching system

The extraction of gold from refractory gold ores(RGOs) without side reactions is an extremely promising endeavor. However, most RGOs contain large amounts of sulfide, such as pyrite. Thus, investigation of the influence of sulfide on the gold leaching process is important to maximize the utilization of RGOs. In this work, the effects of pyrite on the stability of the thiourea system were systematically investigated under different conditions. Results showed that the decomposition rate of thiourea was accelerated sharply in the presence of pyrite. The effect of pyrite on gold recovery in thiourea leaching systems was then confirmed via a series of experiments. The decomposition efficiency of thiourea decreased by 40% and the recovery efficiency of gold increased by 56% after the removal of sulfide by roasting. Under optimal conditions, the efficiency of the gold recovery system increased to 83.69% and only 57.92% of thiourea decomposition was observed. The high consumption of thiourea by the leaching system may be attributed to not only adsorption by mineral particles but also catalytic decomposition by some impurities in the ores, such as pyrite and soluble ferric oxide.     

从难处理金矿中回收金:黄铁矿对硫脲浸金体系稳定性的影响

The extraction of gold from refractory gold ores (RGOs) without side reactions is an extremely promising endeavor. However, most RGOs contain large amounts of sulfide, such as pyrite. Thus, investigation of the influence of sulfide on the gold leaching process is important to maximize the utilization of RGOs. In this work, the effects of pyrite on the stability of the thiourea system were systematically investigated under different conditions. Results showed that the decomposition rate of thiourea was accelerated sharply in the presence of pyrite. The effect of pyrite on gold recovery in thiourea leaching systems was then confirmed via a series of experiments. The decomposition efficiency of thiourea decreased by 40% and the recovery efficiency of gold increased by 56% after the removal of sulfide by roasting. Under optimal conditions, the efficiency of the gold recovery system increased to 83.69% and only 57.92% of thiourea decomposition was observed. The high consumption of thiourea by the leaching system may be attributed to not only adsorption by mineral particles but also catalytic decomposition by some impurities in the ores, such as pyrite and soluble ferric oxide.     

丁二酮肟-氧化剂型无毒浸金剂的浸出性能研究

用分子设计理论提出了一类新型浸金剂 ,它由丁二酮肟和某种氧化剂构成 ,具有无毒害和化学稳定性好的特点 ,实验结果表明 :1)丁二酮肟能与许多氧化剂尤其是高锰酸钾组合成高效浸金剂 ;2 )在丁二酮肟 -高锰酸钾浸出体系中 ,适宜的Ox/Lig(氧化剂与金络剂分子比 )比值范围为 0 .2 5～ 0 .50 ,最佳范围为 0 .30～0 .4 0 ;3)丁二酮肟 -高锰酸钾浸出体系的操作pH范围为 8～ 10 ;4 )与氰化物相比 ,丁二酮肟的浸出率与它相当但浸出速度明显快很多 ;5)从含丁二酮肟的浸出贵液中回收金既可采用炭吸附法也可采用锌置换法 图1,表 5,参 9     

含砷难浸金矿次氯酸钠一步法浸金理论与技术

简单地评述了含砷难浸金矿处理技术的方法和特点,对次氯酸钠浸金的一步法问题进行了初步的讨论,并对次氯酸钠浸金的基础理论作了综述。     

湖南某难处理金矿的加压预氧化-氰化浸金试验研究

针对湖南某难处理金精矿进行预处理技术研究.该矿含砷(质量分数)为11.28%,金的直接氰化浸出率为21.91%.矿石中的砷以毒砂形式存在.载金矿物为毒砂和黄铁矿等硫化物,金为微细浸染型被毒砂和黄铁矿包裹.通过加压预氧化,对矿石进行氰化浸金试验研究.加压氧化最佳条件为初始酸度1 mol/L,木质素磺酸钠5 g/t,硝酸硫酸比7∶1,氧压0.6 MPa,搅拌速度300 r/min,时间100 min,温度100℃,矿浆浓度20%.试验表明经过加压试验后,金的氰化浸出率达到90.87%,与未预处理相比提高了68.96%,达到了较好的试验效果.     

难处理金精矿的加压氧化一氯化浸出实验

采用加压氧化法对国内某难处理金精矿进行预处理,考察了反应温度、精矿粒度、氧分压、初酸浓度、反应时间对金精矿脱硫率和金浸出率的影响.利用XRD,XRF,SEM,EDX技术对金精矿原矿及浸出渣进行分析表征,实验结果表明,在反应温度180℃,精矿粒度-0.075～+0.061 mm,氧分压0.8 MPa,初酸质量浓度60 g...     

难处理金矿的加工方法

为确定难处理金矿的加工方法,在对矿样的的化学成分、粒度分布、赋存状态分析的基础上,进行了相关的浮选条件实验,确定了矿样的最佳浮选工艺流程和参数,并进行了浮选开路实验。结果表明：浮选精矿中的金的回收率为50.97%,金品位为8.75 g/t,精矿中金的回收率和品位都较低,说明该矿样不宜用浮选方法获取精矿,可以考虑用其他方法提金。     

低品位金矿堆浸法提金研究

本文介绍了我国六种金矿类型的二十二个矿区氧化矿石的实验室住式堆浸试验结果,和高岭土化蚀变破碎带金矿氧化矿石的制粒堆浸工业试验;对影响堆浸的诸因素进行了系统的研究;探讨了全浸出过程的动力学特性.这些对堆浸提金工艺的推广应用,有一定的指导意义.     

基于不同粒级硫化铜矿石生物浸出的动力学

西藏甲玛地区的硫化铜矿石中含铜矿物以次生硫化铜矿物为主,且含量较低.采用氧化亚铁硫杆菌柱浸的方法对该矿石进行了生物浸出并研究了浸出动力学.基于不同粒级矿石,考察了粒级对铜浸出速率和浸出率的影响,并对浸出率与收缩核模型中的控制方程进行了拟合,确定了浸出过程的控速环节.试验结果表明,铜的浸出速率和浸出率随粒级的减小而增加.矿石表面形貌的SEM表明,浸出过程中矿石表面形成了包含黄钾铁矾的产物层,阻碍了浸出反应的进行.浸出动力学表明,该矿石的浸出过程符合收缩核模型,且浸出应主要受固体产物层内扩散控制.     

难浸硫化金矿的细菌氧化预处理

用氧化亚铁硫杆菌对两种难漫金矿——四川会东金矿和内蒙古白乃庙金矿进行细菌氧化摇床实验，采用正交实验法确定了细菌氧化的最佳工艺条件，得出了影响脱砷率和除铁率四种因素的主次顺序。     

难浸金矿扩大试验研究

对黔西南州高砷高硫难浸金矿进行二段焙烧预处理，采用氧化剂强化氰金进行扩大试验研究。结果表明：该工艺使金的浸出率达到85％以上，该工艺投资省，无环境污染。     

Accelerating leaching of copper ore with surfactant and the analysis of reaction kinetics

To solve the problem of low permeability and lower extraction rates of high-mud ores, a surfactant was added as a penetrant to the pregnant leaching solution during column leaching tests. On the basis of the theories of physical chemistry and seepage flow mechanics, the mechanism by which seepage is enhanced under the effects of the surfactant was analyzed. The results show that the action modes of the surfactant were divided into four aspects: changing the wettability of the ore, reducing the viscosity of the leaching solution, adsorbing onto the surface of ore, and enhancing the permeability effect. The findings of column leaching tests demonstrated that permeability was substantially improved by the surfactant. In the later period of leaching, the permeability coefficient was two times higher than that of the control group. Meanwhile, the ore extraction rate increased by approximately 10%. During the leaching process, the surface tension of the solution did not substantially change, and that of the solution with surfactant increased slightly. The kinetics analysis of ore column leaching illustrated that the leaching processes were controlled by both internal diffusion(principal factor) and chemical reaction.     

含炭难处理金矿石碘法浸出

用非氰试剂——碘从矿石中浸出黄金，目的是研究碘化浸金取代剧毒氰化物提金的可行性；采用了热力学方法对碘-碘化物溶金的可能性进行了简单分析，用碘-碘化物溶液对含炭难处理金矿石进行了浸出工艺条件实验及与氰化浸出的对比实验，取得了较理想的实验结果：浸出4h金浸出率达到95％，氰化法直接浸出12h金浸出率80％；碘化法浸金速度快，金浸出率高。     

含铜难处理金矿选择性浸出试验研究

针对某含铜难处理金矿进行了碘化法和石硫合剂(lime sulfur synthetic solution,LSSS)法的选择性浸金的研究。结果表明,在碘单质质量浓度为8g/L,浸出时间为2h的条件下,碘化法浸出金的浸出率为88.1%,而且铜的浸出率不足1%。在石硫合剂质量分数为25%,浸出时间为6h的条件下,LSSS法浸出金的浸出率仅为73.5%。对比碘化浸出和石硫合剂浸出效果可知,碘化法对该含铜难处理金矿不仅浸出速度快、浸出率高而且铜几乎不被浸出,具有很强的选择性浸金作用。     

Process mineralogy characteristics of acid leaching residue produced in low-temperature roasting-acid leaching pretreatment process of refractory gold concentrates

To provide a theoretical basis for a suitable process to extract gold from refractory gold concentrates, process mineralogy on the acid leaching residue of gold calcine was studied by chemical composition, X-ray diffraction, scanning electron microscopy-energy spectrum, and mineral dissociation analysis. The results showed that the acid leaching residue contained Au 68.22 g/t, Ag 92.71 g/t, Fe 0.44%, As 0.10%, and S 0.55%. Gold and silver minerals existed as native gold, argentite, and proustite. Quartz, the main gangue mineral, accounted for 78.33wt/%. The dissociation degree analysis showed that the proportions of monomer and exposed gold in acid leaching residue were 96.66wt%. The cyanidation results showed that the cyanide gold leaching rate of acid leaching residues was close to 100wt%. However, the maximum cyanide gold leaching rate of gold calcine was only 85.31wt%. This suggests that acid leaching can increase the gold dissolution rate in the cyanide process.     

超声场对毛细管内电解质浸出过程的影响

为探讨超声场强化化工分离过程的机理 ,以充满电解质溶液的短毛细管中溶质的浸出模拟固液分离体系 ,通过测定浸出动力学曲线 ,探讨了超声场对这一浸取过程的强化作用机理 ,分析了微扰效应对传质过程的影响。实验结果表明 ,超声空化的微扰效应强化了溶质在毛细管内部的扩散 ,且强化作用随毛细管径及超声场强的增大而增大。与升温的强化效果相比较 ,超声场的微扰效应和湍动效应兼顾了强化内外扩散的两个方面 ,与升温浸取过程相比 ,超声场的强化手段更具优势