Application of complexing reagents to flotation separation of the varieties of pyrite

It is considered how the organic reagents, complexing agents, change floatability of the varieties of pyrite with different content of goal. The authors continue studying the flotation effect of the reagent PROX capable to selectively decrease floatability of some pyrite varieties in the presence of xanthogenate due to formation of a hydrophilic complex compound with ferric iron at the phase interface of the mineral surface — liquid, and to reduce sorption of xanthogenate. A phytogenous reagent is suggested as an alternative to the multi-component PROX. The new reagent mechanism is described by examining the chromatographic behavior of the compound of this reagent and ferric iron salt. __________ Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 4, pp. 111–120, July–August, 2007.     

Effect of powerful nanosecond electromagnetic impulses on surface and flotation properties of carbonate-bearing pyrite and arsenopyrite

The effect of powerful nanosecond electromagnetic impulses (PEMI) on the surface and flotation properties of arsenopyrite and carbonate gold-bearing pyrite from the Darasunsk deposit has been studied. X-ray-phase diffractometry, X-ray photoelectronic and IR Fourier-spectroscopy, and raster electronic microscopy were employed in investigations. It was established that the alteration of the phase composition of surface depends non-linearly on terms of treatment (dry or wet) and the number of electromagnetic impulses used and has appreciable influence on oxidation and hydrophobicity of minerals, thus allowing the selective separation of pyrite from arsenopyrite by flotation in the neutral medium. __________ Translated from Fiziko-Tekhnicheskie ProblemyRazrabotki Poleznykh Iskopaemykh, No. 5, pp. 105–118, September–October, 2008.     

Effect exerted by structural features of copper-zinc ores on their oxidation and technological properties

Modeling the oxidation of pyrite copper-zinc ores under evaporization shows that structural features of ores influence the process kinetics, and displays new-formed mineral phases, namely, gannigite, biankite, chalcanthite, which relate with sulfate generating on evaporation from natural and process waters at pyrite deposits. The oxidation effect on the mineral flotation properties is described. __________ Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 4, pp. 101–110, July–August, 2008.     

New complexing agents to select auriferous pyrite and arsenopyrite

The authors propose the process for selective flotation of auriferous pyrite and arsenopyrite, where the combination of xanthate, 2-hydroxylpropyl ester of diethyldithiocarbamate acid (HPEDEDCA) and oak-bark extract (OBE) is used to produce pyrite concentrate recovered into the froth product. The process provides the selective recovery of valuables into heteronymous concentrates, thus reducing the irrecoverable valuable component loss by 5–7 %. The complexing capacity of HPEDEDCA to gold is experimentally proved and allows using it as a selective collector of auriferous iron sulfides. The use of OBE to depress iron sulfides and arsenic in flotation of multicomponent ores contributes to higher flotation selectivity and grade of heteronymous concentrates.     

On regularities observed in formation of liquid phase composition in flotation sulfide pulp

It is shown that modifiers decrease oxidation of pyrite following the line: cyanide > thiosulphate > sulfite > sulfide > dioxide. Action of the modifiers shows itself weaker for other sulfide minerals. The mode of selective flotation of cooper-zinc, copper-pyritic and other products has been developed with allowance for this fact. Iron powder and ferrous iron, as fine reducing agents, advantage to saving the natural surface of a sulfide mineral and improving the flotation selectivity. Decrease in the concentration of copper in liquid phase, that activates sphalerite, and stabilization of anionic composition depend on the mode of pulp conditioning by grinding and flotation, based on the use of various modifiers, their feeding points and pH of the medium. __________ Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 1, pp. 108–119, January–February, 2007.     

Correlation between elemental composition of the surface of gold-bearing pyrite and arsenopyrite and their sorption and flotation properties

Conclusions  1. Crystallostructural estimate of the ionicity of the Fe-S bond in pyrite and arsenopyrite suggests possible shifting of the pyrite electrons toward the anionic core, and this is responsible for the higher reactivity of pyrite vis-à-vis arsenopyrite. 2. The differences in the floatability of pyrite samples from different deposits are caused essentially by the state and elemental composition of the surface. 3. With rise of arsenic content as we go from pyrite to arsenopyrite, mineral extraction falls, and in gold-bearing arsenous minerals the minimum flotation activity corresponds to the maximum gold content. Institute of the Problems of Integrated Exploitation of Mineral Resources, Russian Academy of Sciences, Moscow. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, Vol. 33, No. 6, pp. 110–115, November–December, 1997. This work was carried out with the support of the Russian Fund for Fundamental Research (Project No. 97-05-64010).     

Influence of liquid phase and products of its radiolysis on surface properties of pyrite and arsenopyrite

A feasibility study has been made on improving the contrast of processing properties of pyrite and arsenopyrite, irradiated by accelerated electrons, when these minerals are in the form of neutral, weakly alkaline, and alkaline aqueous suspensions. It has been shown that as a consequence of change in the surface composition, sorption species, and quantity of adsorbed xanthate and its derivatives, the contrast of flotation properties of pyrite and arsenopyrite can be increased by regulating the irradiation dose of the mineral suspension. Institute of Problems of Complex Development of Bowels, Russian Academy of Sciences, Moscow. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 1, pp. 85–91, January–February, 1999.     

Influence of Main Flotation Parameters on Detachment of Hydrophilic Particle from Bubble

The influence exerted by free to move wetted perimeter between three aggregative states and by basic parameters of foam flotation on the size of hydrophilic particles extracted by this method is numerically estimated. __________ Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 4, pp. 94–101, July–August, 2005.     

磨矿方式对闪锌矿和黄铁矿浮选动力学影响研究

为了研究磨矿方式对闪锌矿和黄铁矿浮选行为的影响,通过 6 种浮选动力学模型,分别考察了干磨、湿磨及磨矿时间下 2 种矿物的粒度组成及动力学参数。 结果表明,6 种动力学模型均表现出了良好的拟合效果。 氧化速率、磨矿方式、粒度组成共同决定了闪锌矿和黄铁矿的浮选表现。其中,黄铁矿较闪锌矿具更高的氧化速率及更低的浮选回收率。 湿磨产品较干磨更细,所有试验中-0.015 mm 微细粒级的产率最高,这有利于新生表面的暴露,并导致黄铁矿的快速富集,但同时释放更多 Fe³⁺,降低了闪锌矿的浮选速率。干磨产品粒度组成更粗且颗粒表面粗糙度更高,这促使闪锌矿和黄铁矿干磨后的 ε_∞ 值较湿磨更高。     

磨矿介质对黄铁矿表面性质和浮选行为的影响

利用SEM、XPS现代测试技术及浮选试验考察了瓷磨黄铁矿和铁磨黄铁矿的表面性质与浮选行为。结果表明,分别采用瓷介质与铁介质磨矿时,黄铁矿的表面形态、表面氧化产物及浮选行为存在明显差异。采用瓷介质磨矿时,黄铁矿的浮选效果明显好于采用铁介质磨矿的情形,更有利于黄铁矿的浮选回收。铁磨黄铁矿表面粗糙,腐蚀严重,存在大量的非晶质化亲水性的FeOOH是造成其表面亲水性增强、浮选回收率低的主要原因。     

蛇纹石对黄铁矿浮选的影响及机理

通过浮选实验、沉降实验、显微镜下观测、接触角测试和吸附量实验,研究蛇纹石对黄铁矿浮选的影响,并对其机理进行分析。结果表明：矿物粒度在蛇纹石与黄铁矿的浮选分离中起着重要作用,比黄铁矿粒度小的蛇纹石颗粒能够通过异相凝聚作用吸附在黄铁矿表面,改变黄铁矿的表面性质,影响黄铁矿的浮选。机理研究表明：蛇纹石表面是亲水的且不吸附捕收剂戊黄药(PAX)。蛇纹石吸附在黄铁矿表面,降低了黄铁矿表面疏水性和戊黄药在黄铁矿表面的吸附量,使黄铁矿浮选回收率降低。增加戊黄药在黄铁矿表面的吸附量能够一定程度上恢复被抑制黄铁矿的浮选回收率,但蛇纹石用量较高时,黄铁矿浮选回收率仍降低。因此,微细粒蛇纹石通过异相凝聚作用在黄铁矿表面附着,降低黄铁矿表面疏水性是蛇纹石影响黄铁矿浮选的主要原因。     

Influence of sodium thiosulphate on oxidation of sulphide minerals during selective flotation of copper-nickel ores

The studies of sulphur distribution in oxidation products of pyrrhotite and chalcopyrite being components of Cu-Ni ores showed that the elementary sulphur — sulphoxide ion ratio on the mineral surface and in the liquid phase of mineral suspensions changes in the presence of sodium thiosulphate. Sodium thiosulphate exhibits properties of a reducing agent and prevents formation of hydrophobic elementary sulphur on pyrrhotite surface due to oxygen absorption and oxidation of thiosulphate-ions to sulphates. The decrease in pyrrhotite floatability is observed, and more favorable conditions are provided for selective flotation of chalcopyrite on copper-nickel ore processing. __________ Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 4, pp. 89–94, July–August, 2006.     

Flotation of methylated roughened glass particles and analysis of particle–bubble energy barrier

The impact of the shape and/or anisotropy of particles (in terms of surface energy, surface charge, or wetting) on their flotation separation has been receiving more attention in recent years. The effect of particle surface roughness on interactions with other surfaces or gas bubbles has rarely been studied. The objective of this study was, therefore, to prepare spherical particles of different surface roughness characteristics and test them for their response to flotation separation. Towards this aim, glass particles with a size of 106–150 μm were either acid etched or abraded to manipulate their surface roughness. The particles were also methylated using trimethylchlorosilane to enhance their hydrophobicity and interactions with air bubbles. Micro-flotation separations were then carried out with methylated smooth and roughened particles to examine the effect of particle surface nano-roughness on flotation kinetics and their corresponding recoveries. The results confirmed that the flotation rate constants of roughened particles increased consistently with increasing dimensions of surface asperities. To explain the effect of particle surface roughness on flotation, a theoretical model based on the extended-DLVO interactions was formulated and used to quantify the effect of hydrophobic asperities on particle–bubble surface interactions. The theoretical modeling results suggest, for the first time, that the size of nano-sized hydrophobic asperities distributed over spherical microscopic particles dictate the magnitude of the energetic barrier that particles need to overcome in order to attach to bubbles.     

The influence of pyrite content on the flotation of chalcopyrite/pyrite mixtures

In the flotation of copper ores, several processing plants report that copper recovery is affected by the proportion and reactivity of pyrite in the ore, with the effect becoming more intense when the feed particles are finer as a result of regrinding. In this work, a mixed model mineral system consisting of chalcopyrite (CuFeS₂) and pyrite (FeS₂) with varying pyrite content (20–80 wt.%) was used to investigate the effect of pyrite on the pulp chemistry and chalcopyrite recovery. Flotation tests showed that chalcopyrite flotation rate, recovery and grade, as well as the pulp oxidation potential, decreased with increasing pyrite content whilst pyrite recovery increased. Surface analysis (XPS, ToF-SIMS and EDTA) indicated that copper activation of pyrite increased with increasing pyrite content, facilitating pyrite recovery. The decrease in chalcopyrite recovery can be attributed to increased surface oxidation.     

Kinetic regulations in flocculation of fine-dispersed washed products: Two mechanisms for micron and submicron particles

The article discusses experimental results on flocculation of coal flotation waste. In analyzing kinetics of sedimentation and structure of flocs, it has been found that flocculation of particles larger than 1 μm follows the orthokinetic mechanism within fractions of second, while flocculation of submicron particles runs the perikinetic mechanism in 400–600 s. The structural features of the mechanism-related flocs are revealed.     

微细粒黄铁矿柱浮选试验

研究了用旋流喷射浮选柱浮选-19 μm占86.88%微细粒黄铁矿单矿物时,药剂用量和充气速率对总回收率和粒级回收率的影响,比较了旋流喷射浮选柱与普通浮选机对该微细粒黄铁矿的回收效果。结果表明：用旋流喷射浮选柱浮选微细粒黄铁矿时,起泡剂用量和充气速率有一个适宜的中间值,而捕收剂用量应在本试验最大用量的基础上进一步增加,以弥补因极细粒矿物消耗大量捕收剂而引起的捕收剂总量不足。浮选柱对-19 μm黄铁矿的回收效果明显优于浮选机,对19~30 μm黄铁矿的回收效果则与浮选机基本相同;两种浮选设备对-3 μm黄铁矿的浮选效果都不理想。     

蛇纹石与黄铁矿间的异相凝聚/分散及其对浮选的影响

通过浮选试验、浊度测定、ζ电位测定和吸附量测定, 研究了蛇纹石与黄铁矿间的异相凝聚/分散及其对浮选的影响。结果表明, 在pH=7～10.2, 蛇纹石与黄铁矿表面间静电力表现为引力, 颗粒间的异相凝聚严重, 且当蛇纹石量占黄铁矿量5%时, 就会显著降低黄铁矿回收率。原因是蛇纹石异相凝聚于黄铁矿表面, 不仅自身的可浮性差, 还会降低戊基黄药在黄铁矿表面的吸附量。增加捕收剂用量或添加六偏磷酸钠均能有效改善黄铁矿的浮选。六偏磷酸钠可以使蛇纹石表面ζ电位由正转负, 有效减弱异相凝聚。     

某浓密机溢流中极微细粒黄铁矿的浮选回收试验

某铅锌浮选尾矿浓密机溢流中含有大量的微细粒黄铁矿等,-40、-5 μm粒级产率分别高达99.40%和33.50%,黄铁矿一般小于30 μm,主要呈自形、半自形粒状,解离程度好,94.93%的黄铁矿以单体形式存在,在40～5 μm粒级有明显的富集现象。为了提高资源的利用率,提高企业的经营业绩,减少尾矿库的堆排量并改善尾矿库工艺参数,对微细粒黄铁矿进行了选矿试验研究。结果表明,采用2粗2精、中矿顺序返回流程处理该试样,可获得硫品位为46.90%、回收率为86.64%的硫精矿,试验指标理想,可作为设计依据。     

Scientific grounds for high-performance agent modes in platiniferous sulfide mineral flotation from rebellious ores

The author substantiates the choice of new selective agents PTTC, HPEDETC, and Hostaflot M-91 to float platiniferous sulfide minerals from rebellious ores. The study agent modes imply the use of PTTC, being a component of modified xanthate and providing 6–7% increase in recovery of copper, nickel, and PGM in flotation of the low-sulfide platiniferous copper-nickel ore from the Fedorovo-Pansky deposit. The substitution of HPEDETC and Hostaflot M-91 for xanthate makes it possible to increase recovery of platinum by 5.7–13%, palladium by 4–9% and 2–4 times the noble metal content in the flotation concentrate.     

凡口铅锌矿选硫生产实践

介绍凡口矿的选硫历史 ,并从药剂制度、流程结构、给矿浓细度等方面探讨提高选硫指标的方法 ,认为活化剂硫酸和捕收剂黄药采用分步加药、提高入选搅拌时间、控制入选浓度、抛弃难选的细颗粒和使用适合凡口矿选硫的 6A浮选机等办法 ,可提高选硫的生产指标。