不同矿床伴生黄铁矿的物性特征及可浮性研究

研究了大厂锡石多金属矿、凡口铅锌矿和武山铜矿伴生黄铁矿的物性特征，考察了它们在丁黄药体系中的可浮性及CaO对它们的抑制作用。结果表明：大厂黄铁矿和凡口黄铁矿的半导体类型为p型，武山黄铁矿的半导体类型为n型；3种黄铁矿的硫铁比大小顺序为大厂型→凡口型→武山型，而晶格点阵常数大小顺序为大厂型→武山型→凡口型。3种黄铁矿的可浮性主要与其半导体类型和硫铁比有关，被CaO抑制的难易程度则主要受其晶格点阵常数影响，即半导体类型为p型和硫铁比大的黄铁矿其可浮性更好，而晶格点阵常数大的黄铁矿更易被CaO抑制。     

不同成因类型黄铁矿的浮游特性

采用乙黄药作为捕收剂,Na2S,CaO,CuSO4,ZnSO4,Na2SO3和腐植酸钠作为调整剂研究5种不同成因类型黄铁矿的浮游性.结果表明,不同成因类型黄铁矿无捕收剂浮选时的天然可浮性存在明显差异.用乙黄药做捕收剂时,不同成因黄铁矿之间存在浮游差,但基本浮游规律相近.热液叠加改造型的浮选速度最快,其次是中高温热液型、块状硫化物型和硅卡岩型,而煤系黄铁矿的浮游速度最慢.矿浆pH对不同成因黄铁矿有明显影响,天然可浮性越好的黄铁矿受矿浆pH的影响大.调整剂CuSO4,CaO,Na2SO3,Na2S和腐植酸钠对不同成因的黄铁矿多为抑制作用,ZnSO4对不同成因黄铁矿浮游性的影响不大.     

被井下充填体污染金矿石的活化浮选试验

针对山东新城金矿矿石被井下强碱性充填体污染而造成金回收率下降的问题,以硫酸、工业草酸、硫酸铜为活化剂进行了黄铁矿的活化浮选试验。试验结果表明：硫酸在矿石污染较轻和矿石污染严重时对黄铁矿的活化效果都较好,可使金总回收率提高2~3个百分点;工业草酸在矿石污染较轻时对黄铁矿的活化效果较好,而在矿石污染严重时活化效果不明显;硫酸铜则活化效果较差。     

某铁精矿降硫试验

针对某高硫铁精矿铁品位为60%,含硫高达4.15%,无法达到销售要求的情况,对其主要含硫矿物磁黄铁矿,通过细磨、添加活化剂等手段,提高了其可浮性,达到了磁黄铁矿与磁铁矿良好的浮选分离效果,最终将铁精矿硫含量降至0.45%,满足了质量要求。     

黄铁矿浮选活化机理研究进展

黄铁矿是自然界中储量最丰富的硫化矿之一，常与铅、锌、铜等价值较高的硫化矿共生。针对被高碱抑制的黄铁矿，常使用活化剂改善其可浮性，从而活化选硫，而活化剂对黄铁矿表面性质的影响是研究其作用机理的关键。本文详细阐述了黄铁矿晶体性质，包括其微观晶体结构、能带结构、态密度、Mulliken布局、电化学性质等；以黄铁矿表面物种演变为切入点，介绍了表面杂质掺杂、空位缺陷和表面氧化对其可浮性的影响。综述了离子活化和活化药剂的作用机理：铜、铅离子活化会在黄铁矿表面形成吸附活性位点，促进捕收剂吸附；酸类活化剂会清除黄铁矿表面亲水沉淀和氧化产物；盐类活化剂则会与黄铁矿表面原子反应，改变黄铁矿表面性质和水化层结构，从而促进浮选。加强对活化剂作用过程中黄铁矿表面性质的观察、表征、精确计算和模拟，可为黄铁矿的高效清洁活化剂研发、资源合理利用和环境保护提供一定科学依据。     

多金属硫化矿混合浮选高效活化剂试验研究

针对广西大厂锡石多金属硫化矿的矿石性质进行了矿物分析和选矿试验研究,研发了混合浮选高效活化剂LJ,代替了传统的活化剂硫酸铜进行活化,提高该硫化矿全浮效果和铁闪锌矿浮选效果,新型混合浮选高效活化剂LJ选择性和活化性能更强,成本更低。     

无捕收剂浮选的半导体能带理论讨论

用量子力学计算得到了方铅矿(PbS)和黄铁矿(FeS_2)的半导体能带图,以及分子氧和HS-离子的HOMO和LUMO的能量。计算结果画成方铅矿和黄铁矿半导体与分子氧和HS-离子作用的能级图,从电子转移微观层次上解释这两类矿物的无捕收剂浮选机理(包括自诱导浮选和硫化钠诱导浮选)。结果表明,P型半导体(以黄铁矿为典型代表)具有良好硫化钠诱导浮选行为,N型半导体(以方铅矿为典型代表)具有良好自诱导浮选行为。电子载流子浓度(n_e)与空穴载流子浓度(n_p)之比值可以作为一个参数来判断无捕收剂浮选行为:n_c/n_p值大,自诱导浮选行为好;n_p/n_e值大,硫化钠诱导浮选行为好。     

黄铁矿的抑制及活化分选研究进展

黄铁矿资源储量大，共伴生有色金属价值高，在当下资源紧张和环境压力严峻的态势下，其高效清洁利用技术的开发意义重大。目前选矿界对含黄铁矿的有色金属硫化矿的浮选分离工艺主要是抑制黄铁矿，先回收其它有用金属矿物，随后再活化捕收黄铁矿。但是受黄铁矿晶体缺陷、化学成分差异等因素的影响，加之浮选体系的多样化和复杂化，浮选实践中常常出现黄铁矿与其他硫化矿物分离效果不理想，再活化效果不佳等问题。本文综合了国内外关于黄铁矿晶体微观物理化学结构、抑制剂及其抑制机理、活化剂及其活化机理方面的研究现状，对黄铁矿资源的综合利用具有一定的参考价值。      

丁基铵黑药体系下单斜磁黄铁矿浮选行为及其表面吸附机理

通过丁基铵黑药药剂用量及矿浆pH对未活化和活化单斜磁黄铁矿浮选试验,以及单斜磁黄铁矿表面ζ电位及红外光谱测定,研究丁基铵黑药体系下,单斜磁黄铁矿的浮选行为及其表面吸附机理。结果表明,单斜磁黄铁矿在弱酸性及中性条件下可浮性最好,Cu~(2+)对其有一定的活化效果。丁基铵黑药在单斜磁黄铁矿表面为化学吸附,其表面生成正二丁基二磷酸亚铁。     

硫铁矿浮选中的活化研究进展

从可浮性、活化机理、活化应用三个方面分别概述和分析了黄铁矿和磁黄铁矿的活化研究进展,并认为在今后浮选仍然是硫铁矿选矿的主要发展趋势;现代选矿测试技术的发展,将推动硫铁矿的活化机理研究;目前需要开发环保、来源广和低廉的硫铁矿活化剂。     

(NH4)2S2O8氧化载金黄铁矿规律及E-pH研究

采用基于硫酸根自由基(SO4-·)的高级氧化技术,将(NH₄)₂S₂O₈作为氧化剂氧化预处理黄铁矿。考察了(NH₄)₂S₂O₈和FeSO₄浓度、浸出温度、浸出时间对氧化浸出黄铁矿效果的影响。结果表明,采用热活化(NH₄)₂S₂O₈产生SO₄-·预处理黄铁矿,在(NH₄)₂S₂O₈浓度0.395 mol/L、浸出温度70 ℃、浸出时间8 h条件下,黄铁矿浸出率可达73.71%。通过动力学方程拟合,确定该体系浸出黄铁矿可采用收缩核动力学模型描述,浸出黄铁矿过程中反应速率的决定步骤为内扩散速率,其表观活化能为50.57 kJ/mol。通过绘制FeS₂-(NH₄)₂S₂O₈-H₂O体系E-pH图分析可知,常温下过硫酸盐溶液具有较高的氧化还原电位,理论上采用过硫酸盐氧化分解产生SO₄-·浸出黄铁矿具有可行性。     

氧化锰矿泥浸出液除杂净化和产品制备试验研究

选取硫铁矿、玉米秆和废糖蜜作为还原剂对广西某氧化锰矿泥进行还原浸出, 在锰浸出率都达到95%以上的条件下, 对3种浸出液采用部分水解针铁矿法除铁、硫化法除重金属, 除杂净化后液用于制备硫酸锰或碳酸锰。结果表明, 以硫铁矿为还原剂的锰浸出液铁离子较易除去, 玉米秆次之, 废糖蜜较难, 3种不同还原剂的浸出液除铁率分别为99.98%, 99.91%、和99.48%; 在相同净化条件下, 3种不同还原剂的浸出液除重金属净化效果并无明显差异, 均能达到很好的除杂效果; 以硫铁矿为还原剂的锰净化液可制得合格的工业级硫酸锰产品, 以玉米秆和废蜜糖为还原剂难以制得合格的硫酸锰产品。3种还原剂的锰净化液都可制成合格的碳酸锰产品, 产品级别硫铁矿还原时优于玉米秆、废糖蜜, 最终锰的回收率分别为88.37%、82.56%和81.71%。     

乙硫氮作捕收剂时无机调整剂加药顺序对典型硫化矿物浮选的影响

研究了乙硫氮作捕收剂时无机调整剂硫酸锌、亚硫酸钠、硫化钠和硫酸铜不同加药顺序对典型硫化矿物黄铜矿、方铅矿、闪锌矿和黄铁矿浮选行为的影响。结果表明,调整剂与捕收剂的加药顺序对硫化矿物浮选的影响不同。与调整剂先加时相比,乙硫氮先加时,硫酸锌对黄铜矿和方铅矿浮选的抑制作用减弱;硫酸锌、低用量硫酸铜、亚硫酸钠或硫化钠对闪锌矿浮选以及硫酸铜对黄铜矿和方铅矿浮选的抑制作用更强;硫酸锌或硫酸铜对黄铁矿浮选以及较高用量硫酸铜对闪锌矿浮选的活化作用相当;亚硫酸钠或硫化钠对黄铜矿、方铅矿和黄铁矿浮选的影响很小。研究结果可为部分硫化矿通过改变调整剂与捕收剂的加药顺序提高矿物浮选分离效率提供借鉴。     

Pyrite activation in amyl xanthate flotation with nitrogen

The low potential hydrophobic state of pyrite in amyl xanthate (PAX) flotation with nitrogen is of particular interest with regard to the N₂TEC flotation technology currently being used for the recovery of auriferous pyrite at Newmont’s Lone Tree Plant in Nevada. Initially, the N₂TEC system had been found to operate satisfactorily, but cyanide in the flotation mill water appeared to be responsible for a loss in pyrite recovery. This supposition was confirmed with laboratory experiments, and a program was initiated to study flotation chemistry variables by electrochemically controlled contact angle measurements. Experimental results show that activation of pyrite in such cyanide solutions can be achieved more effectively with lead than with copper. Subsequently, based on these fundamental studies, significant improvement at the Lone Tree Plant was achieved by lead activation, in which case the recovery increased to expected levels.The effect of activator is particularly significant not only with respect to pyrite depression by residual cyanide, but also with respect to collector (PAX) consumption and the initial state of the pyrite surface. Experimental results show the importance of the pyrite surface state and the rather interesting features of the activation process.     

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.     

硫化矿尾矿水对黄铁矿浮选性能的影响

针对会泽铅锌矿硫化矿尾矿水对黄铁矿浮选性能的影响,分别采用丁黄药和乙硫氮做捕收剂,研究在尾矿水和去离子水中黄铁矿的可浮性。在去离子水中以丁黄药和乙硫氮做捕收剂的条件下,分别加入硫酸锌、硫酸铜和水玻璃作为调整剂,研究对黄铁矿浮游性的影响。结果表明;尾矿水中某些成分对黄铁矿的可浮性有强烈的抑制作用,该尾矿水直接回用会对黄铁矿的浮选产生不利影响。丁黄药和乙硫氮对黄铁矿都有很好的捕收能力,硫酸锌、硫酸铜和水玻璃3种调整剂在不同捕收剂条件下对黄铁矿浮游性的影响不同。     

Visualization of initial attachment of bioleaching bacteria using combined atomic force and epifluorescence microscopy

Bioleaching is the dissolution of metal sulfides, such as pyrite and chalcopyrite, by bacterial oxidation processes. It has been found that attachment of leaching bacteria to the mineral surface enhances the metal sulfide dissolution. The interaction of mixed cultures with respect to initial attachment processes has not been investigated. Therefore in this study we quantified and visualized initial colonization on pyrite by pure and mixed cultures. Strains of the genera Acidithiobacillus and Leptospirillum were tested. Sessile and planktonic cells were visualized by fluorescence microscopy using DAPI, FISH, Syto? 9, lectin- and calcofluor-staining. Additionally, atomic force microscopy (AFM) was used for the investigations on cell morphology, spatial arrangement of cells on pyrite and mineral surface topography. The morphology of planktonic and sessile cells is different. Moreover, planktonic cells show differences in morphology due to the use of different substrata. By using different visualization methods it could be proven that colonization and biofilm formation on pyrite in mixed cultures is mostly dominated by Leptospirillum spp. Interactions of different species resulted in increased production of extracellular polymeric substances (EPS) or caused bacteria showing little tendency to attach when in monoculture to be incorporated into a biofilm by those that attach preferentially. Consequently, biofilm formation and metabolic diversity were furthered. One of the most important results is the finding that not all bioleaching bacteria are involved to the same extent in biofilm formation. Thus, further work shall allow us elucidate the important bacteria for biotechnological use, thereby leaching processes can be faster, more efficient and costs can be reduced.     

硫精砂替代黄铁矿生产亚硫酸工业试验

本试验在小型试验的基础上,确定硫精砂压制球团的最佳配比为:硫精砂∶A∶B∶C=100∶1∶2∶18,并以此配比压制硫精砂球团作为试验原料。在原有以黄铁矿生产亚硫酸的生产线上做试验,有针对性地对原鼓风炉结构进行了技术改造,以适应硫精砂球团入炉熔炼所需的床能力和燃烧强度。试验结果表明,硫精砂球团的含硫量和强度满足生产要求;硫精砂球团入炉熔炼反应充分,炉况和渣型良好;亚硫酸浓度大于0.4%,满足选矿生产要求。