Effects of free cyanide and cuprous cyanide on the flotation of gold and silver bearing pyrite

At gold and silver mineral processing plants, cyanide species are always present in the process water recycled to flotation circuits, despite the cyanide destruction process. The effect of cyanide, in particular, cuprous cyanide on gold and silver flotation has not been well understood. In the present study, free cyanide and cuprous cyanide species were isolated and their effects on the flotation of a pyritic ore were evaluated. It was found that free cyanide depressed gold and silver flotation through their carrier, pyrite. Cuprous cyanide mainly in the form of Cu(CN)₃²⁻ depressed pyrite flotation similarly as free cyanide. Electrochemical studies including open circuit potential (OCP), cyclic voltammetry and electrochemical impedance spectroscopy (EIS) techniques were carried out to understand the underpinning depression mechanism of cyanide species on pyrite flotation using xanthate as collector. It was found that all surface electrochemical reactions were inhibited by either free cyanide or cuprous cyanide. The surface layer as a result of xanthate adsorption on pyrite was completely removed in the presence of these cyanide species, which was suggested to contribute to the hydrophilic pyrite surface.     

低品位复杂难选铜铅锌矿选铜工艺

四川会理铅锌矿有半个多世纪的开采历史,矿产资源丰富,但是矿石结构复杂,有用矿物共生现象严重,属于铜铅锌难分离矿石。由于矿石性质变化,在铜原矿品位0.5%,铜精矿主品位17.61%,铅锌杂质24.21%,铜回收率40.26%的情况下,我们在现有的流程基础上,通过调整药剂用量和添加硫化钠,与技改之前相比铜精矿铜品位提高了2.65个百分点,铅锌杂质含量降低了12.4个百分点,铜回收率提高了35.02个百分点。      

蒙古国萤石矿浮选试验研究

通过对蒙古国的萤石矿样进行选矿试验研究,确定采用一次粗选、一次扫选、六次精选、中矿顺序返回的选矿工艺,获得了Ca F2品位为98.27%、回收率为90.14%的萤石精矿,其中Si O2含量为0.68%,Ca CO3含量为0.29%,杂质含量较少,为该资源的开发利用提供了基础依据。     

湖南醴陵某高砷金矿浮选试验研究

湖南醴陵某高砷金矿含Au 2.85g/t,含As 0.2%,金主要以自然金形式存在,矿石中主要金属矿物为黄铁矿和毒砂。针对该矿性质进行了抑砷浮金试验研究,试验采用亚硫酸钠+腐殖酸钠作毒砂抑制剂,丁黄药+丁铵黑药作含金矿物捕收剂,在磨矿细度为-74μm 65%的条件下,闭路试验获得含Au 112.30 g/t、含As 0.27%的金精矿,金回收率85.20%,脱砷率达到97.56%,获得了较好的试验指标。     

极性基团协同效应原理在氧化锌矿石捕收剂开发中的应用现状

多极性基团之间协同作用对捕收剂的捕收性能和选择性具有重要影响,基于极性基团间的协同效应开发新型、高效的浮选药剂已成为国内外研究的热点。对极性基团间协同作用在强化氧化锌矿石捕收剂浮选性能中的应用情况进行总结和分析。结果表明,多键合作用可以显著提升捕收剂对含锌氧化矿物的捕收性能和分选效率,极性基团间电子效应则可改善捕收剂的物理化学性能提高浮选效率。深入研究极性基团协同作用机理,对精准调控捕收剂浮选能力具有重要意义。     

陕西某难选金矿浮选试验研究

针对某难选金矿金品位为2.93 g/t,磨浮过程泥化较严重,并且主要载金矿物为黄铁矿和毒砂的特点,采用调整剂Na2CO3用量为3000 g/t,抑制剂水玻璃用量为1500 g/t,活化剂硫酸铜用量为250 g/t,用丁基黄药和丁铵黑药以1∶1组合作捕收剂,经过两粗两扫三精闭路浮选流程试验,获得了含金品位38.4 g/t、回收率为84.73%的金精矿,取得了较好的选矿效果。     

某多金属含金难处理矿石浮选工艺研究

某多金属含金难处理矿石含铜0.21%、金0.55 g/t。对该矿进行捕收剂和调整剂优化试验,确定了粗选采用石灰调整矿浆、Z-200与丁基铵黑药为组合捕收剂,扫选采用丁基黄药与丁基铵黑药为组合捕收剂的新药剂制度。粗扫选作业的差异化给药,有效提高了铜、金的回收指标。在磨矿细度-74μm占68.63%的条件下,通过一次粗选、三次精选、三次扫选的闭路流程试验,获得精矿含铜14.72%、含金23.45 g/t,铜回收率90.29%、金回收率60.92%的指标。     

从库存金尾矿中回收金的试验研究

河南金渠黄金股份有限公司金渠金矿已闭库的马桥沟尾矿库存有尾矿180万t左右,平均金品位达0.87 g/t。为开发利用该尾矿,对其进行了浮选试验研究。试验结果表明,在-200目占78%的再磨细度下,采用丁基黄药+丁铵黑药作为联合捕收剂,辅之以硫酸铜的活化作用,经一粗二精二扫闭路浮选,可从该尾矿中获得金品位为12.49 g/t,金回收率为81.36%的金精矿。     

OP表面活性剂在磷矿浮选脱硅中的增效作用

为了研究辛基酚聚氧乙烯醚(OP)系列表面活性剂对油酸钠浮磷脱硅的增效作用,选用不同的环氧乙烷加成数的OP表面活性剂来复配油酸钠,通过纯矿物浮选试验和实际矿物浮选试验,来选取最佳的OP表面活性剂以及复配比例,通过泡沫性能测试、表面张力测定以及红外光谱,来探索OP表面活性剂的增效机理.纯矿物浮选试验表明,OP系列表面活性剂...     

Synthesis of 2-ethyl-2-hexenal oxime and its flotation performance for copper ore

A novel collector 2-ethyl-2-hexenal oxime was synthesized from 2-ethyl-2-hexenal and hydroxylamine hydrochloride. The yield of oxime was 78.05% under the optimum experimental conditions. The oxime was characterized by elemental analysis, infrared spectrum, mass spectrum, ¹H NMR and ¹³C NMR spectroscopy. The results of ultraviolet spectrum showed that the oxime exhibited stronger reaction affinity with Cu²⁺ than with Ni²⁺ or Fe³⁺, etc. Infrared spectroscopic analysis implicated that the oxime bound to Cu²⁺ through both the CC and CN groups. Microflotation tests of pure malachite mineral and chalcopyrite mineral indicated that the recovery of chalcopyrite was 91.16% under the flotation condition of rougher pH 10 and collector concentration of 200 mg/L, and the recovery of malachite reached 90.56% under the flotation condition of rougher pH 11.5 and collector concentration of 250 mg/L. The results of flotation tests of sulfide–oxide copper from Dexing copper mine showed that 2-ethyl-2-hexenal oxime achieved an excellent mean concentration containing 4.52% Cu with 79.54% Cu recovery, and the Cu average recovery increased by 2.35% compared to that of butyl xanthate.     

某含铅锌金矿石全泥氰化—尾渣浮选铅锌试验研究

某含铅锌金矿石中金属硫化物之间存在较复杂的矿物共生关系,以减少金的损失为优先条件,通过选矿试验研究,采用原矿全泥氰化;尾渣浮选铅锌工艺流程,金回收率达到95.69%,同时获得合格铅精矿和锌精矿,铅精矿品位66.41%、回收率79.24%,锌精矿品位51.88%、回收率89.49%。     

The influence of the oxidation state of pyrite and arsenopyrite on the flotation of an auriferous sulphide ore

In this paper, the influence of the oxidation state of pyrite and arsenopyrite on the flotation of an auriferous sulphide ore was investigated by different techniques, including electrode, pulp potentials, DRIFT spectroscopy and microflotation tests. In addition, the gold and sulphide recoveries were also investigate, in a laboratory-scale cell, as a function of pulp potential and reagent concentration. It was verified that the presence of oxidation products on the sulphide mineral surface demands a higher collector concentration in order to achieve a satisfactory sulphide recovery. The electrochemical behaviour of pyrite and arsenopyrite indicated that a nitrogen atmosphere can lead to a low pulp potential, which inhibits the formation of oxidation products, enhancing both the free gold and sulphide recoveries. Although copper sulphate activates even oxidised sulphide surfaces, it does not improve free gold recovery.     

某含银复杂铜铅锌多金属硫化矿浮选试验

对云南某高硫铅锌矿进行选矿实验研究。原矿铅品位2.98%、锌品位2.79%、银品位114.95 g/t,在磨矿细度为-0.074 mm 76.19%条件下,采用优先浮选工艺流程,以硫酸锌+碳酸钠作为组合抑制剂,以新型捕收剂HQ-Pb作为铅捕收剂,最终获得铅品位56.62%、银品位1915.38 g/t的铅精矿,铅回收率82.36%,银回收率73.44%;获得锌品位45.92%、银品位171.38 g/t的锌精矿,锌回收率82.29%,银回收率7.58%。     

The interaction of sodium mercaptobenzothiazole with gold electrode and nanorod surfaces

Attenuated total reflectance Fourier transform infrared spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy and transmission electron microscopy have been applied to characterise and investigate the interaction of sodium mercaptobenzothiazole (MBT) with gold surfaces and gold nanorods. Gold nanorods (Au NRs) with average aspect ratio of 4.04 ± 0.08 were synthesised and reacted with MBT. Gold(I) mercaptobenzothiazole and the dithiolate, 2,2′-dithiobisbenzothiazole ((MBT)₂) were synthesised and characterised to provide a basis for compound identification. It was concluded that MBT could link two Au NRs by adsorption through the exocyclic S atom on one NR and the endocyclic S atom on the other NR, thereby leading to the formation of Au nanochains in the suspension. The MBT flotation of 100 μm gold particles was also investigated utilising controlled potential techniques. The gold metal particles floated in the cell when the potential reached 0.5 V. At that potential, (MBT)₂ was observed on the gold particles, and their floatability was attributed to the adsorption of that dithiolate species.     

某高品位金矿石重—浮—浸综合回收试验研究

阐述了采用重选—浮选—氰化浸出处理某高品位金矿石的工艺。工艺的试验结果体现了联合流程处理高品位金矿石的优势。最终,金的总回收率高达99.64%,伴生银回收率为89.86%,硫回收率为87.66%。     

Effect of amine and starch dosages on the reverse cationic flotation of an iron ore

In iron ore concentration, reverse cationic flotation of quartz has been successfully employed for particles below 150 μm previously deslimed. Amine and starch are used, respectively, as quartz collector and iron oxides depressant. Understanding the mechanisms of reagents interaction is relevant to improve the separation selectivity, especially for high amine dosages. The term clathrate was used to explain this interaction, meaning a molecular compound in which molecules of one species occupy the empty spaces in the lattice of the other species, resulting in the depression of hydrophobic minerals. Laboratory scale experiments were carried out with itabirite iron ore in three different size ranges. The clathrate formation between molecules of amine and starch may explain the increase of SiO₂ content in the concentrates of the coarse size range (−150 + 45 μm) due to an increase in amine dosage.     

甘肃省礼县某金矿选矿试验研究

甘肃省礼县某金矿石含金5.67 g/t、银3.1 g/t、含硫2.67%,矿石性质研究结果表明,矿石中金矿物嵌布粒度细,裸露半裸露金可浮性较差是影响金回收的主要原因。试验通过对金矿物活化剂和捕收起泡剂研究,确定了碳酸钠作调整剂、T31作活化剂,丁基黄药作捕收剂,A25作捕收起泡剂的药剂制度,小型试验和工业试验均取得了良好的技术指标。     

Selective flotation of scheelite from calcite and fluorite using a collector mixture

Collector 733, a sodium soap (C_12–16COONa) is widely used industrially for scheelite flotation. Low selectivity of 733 collector is always observed. In this study, a collector mixture of 733 and MES (sodium fatty acid methyl ester sulfonate) demonstrated a high selectivity for the flotation of scheelite from calcite and fluorite. An optimal mass ratio 4:1 of 733:MES was found, producing a 65.76% WO₃ concentrate grade with a recovery of 66.04% from a feed material containing only 0.57% WO₃. In addition, the effect of water hardness and water glass addition were studied. The results indicated that the presence of Ca²⁺ or Mg²⁺ had little effect on the adsorption of the collector mixture at the scheelite surface. Addition of water glass for depressing calcite and fluorite had no significant effect on the adsorption of the collector mixture on the scheelite surface. The advantages of this new collector mixture (733+MES) include lower cost, low dosage, high tolerance against water hardness and high selectivity, and this collector mixture has great potential for industrial application.     

青海某金矿浮选尾矿环保提金试验研究及实践

青海某金矿矿石性质属典型的难处理金矿,在生产初期处理混合矿石,浮选回收率较低。基于浮选尾矿矿石性质开展CIL环保提金剂浸出试验研究,环保提金剂浸出生产实践表明,浮选尾矿金的浸出率为53.95%,选矿总回收率达到92.7%,浸出生产成本降低6元/t,年经济效益增加378万元,实现了浮选尾矿环保浸出清洁化生产。