金属离子在矿物浮选中的典型作用

在矿物浮选中,金属离子可以通过选择性活化或抑制矿物表面,从而发挥重要的作用.尽管此前大量工作报道了金属离子在浮选中的作用,但大多仅是针对某一特定类型金属离子或目的矿物进行研究分析,缺乏一个全面的综述.本文对金属离子在矿物浮选中的影响因素进行详细分类,总结金属离子在不同种类矿物浮选中的作用机理.此外,还对常见探索作用机理...     

Preliminary examination of electrochemical and spectroscopic features of trithiocarbonate collectors for sulfide mineral flotation

1　ＩＮＴＲＯＤＵＣＴＩＯＮＳｉｎｃｅｔｈｅ 192 0’ｓ ,ｔｈｅｄｉｔｈｉｏｃａｒｂｏｎａｔｅｓ (ｘａｎ ｔｈａｔｅｓｏｒＤＴＣ)ｈａｖｅｂｅｅｎｔｈｅｐｏｐｕｌａｒｃｏｌｌｅｃｔｏｒｓｏｆｃｈｏｉｃｅｆｏｒｓｕｌｆｉｄｅｍｉｎｅｒａｌｆｌｏｔａｔｉｏｎ .Ｔｈｅｙｈａｖｅｓｅｖｅｒａｌａｄｖａｎｔａｇｅｓｏｖｅｒｏｔｈｅｒｃｏｌｌｅｃｔｏｒｓｉｅｔｈｅｙａｒｅｉｎｅｘｐｅｎ ｓｉｖｅ ,ｅａｓｙｔｏｐｒｏｄｕｃｅ ,ａｖａｉｌａｂｌｅｉｎｓｏｌｉｄｆｏｒｍ ,ｔｏｔａｌｌｙｗａｔｅｒ ｓｏｌｕｂｌｅａｎｄｖ…     

FTIR spectroscopic study of electrochemical flotation of jamesonite-diethyldithiocarbamate system

1 Introduction Flotation electrochemistry and modern surface analytical techniques have enhanced our understanding of reagent-mineral interaction mechanism. Great progress has been made by applying various electrochemical techniques to investigate the int…     

Recent advances in electrochemistry of sulfide mineral flotation

1　ＥＬＥＣＴＲＯＣＨＥＭＩＳＴＲＹＯＦＦＬＯＴＡＴＩＯＮＩｔｉｓｎｏｗｏｖｅｒ 4 0ｙｅａｒｓｓｉｎｃｅＮｉｘｏｎｐｒｏｐｏｓｅｄａｎｅｌｅｃｔｒｏｃｈｅｍｉｃａｌｍｅｃｈａｎｉｓｍｔｏｅｘｐｌａｉｎｔｈｅｉｎｔｅｒａｃｔｉｏｎｏｆｔｈｉｏｌｆｌｏｔａｔｉｏｎｃｏｌｌｅｃｔｏｒｓｗｉｔｈｓｕｌｆｉｄｅｍｉｎｅｒａｌｓｕｒ ｆａｃｅｓａｎｄｐｒｏｖｉｄｅａｍｅａｎｓｏｆｒｅｃｏｎｃｉｌｉｎｇｔｈｅｄｉｆｆｅｒｅｎｔｔｈｅｏｒｉｅｓｔｈａｔｈａｄ ｐｒｅｖｉｏｕｓｌｙｂｅｅｎｒｅｓｏｌｕｔｅｌｙａｄ ｖ…     

Effect of mineral processing wastewater on flotation of sulfide minerals

The effects of mineral processing wastewater on sulfide minerals were investigated by flotation, infrared spectrometry and electrochemistry test. The results show that lead-concentrate water can improve the flotation of galena, while the sulfur-concentrate water has negative effect on flotation of galena compared with distilled water. The flotation behavior of pyrite is contrary to that of galena in three kinds of water. Infrared spectra indicate that the residual collector in the lead-concentrate water is beneficial to the formation of lead xanthate on the surface of galena. Electrochemistry results indicate that electrochemistry reaction on galena surface has apparent change. The anode polarization is improved and cathode polarization is depressed.     

不同金属硫化物从钨酸盐溶液中除钼的效果

针对钨冶炼过程中钨钼分离这一关键问题,研究了利用CuS,CoS,NiS,PbS,FeS,ZnS和HgS等金属硫化物从钨酸盐溶液中除钼的效果.对含钼的Na2WO4或(NH4)2WO4溶液用Na2S或(NH4)2S 进行硫化处理,使其中的MoO2-4转化为MoS2-4,然后加入上述金属硫化物进行除钼.结果表明,CuS,CoS和NiS在Na2WO4或(NH4)2WO4溶液中均具有良好的除钼效果,综合考虑经济、环保等因素,认为CuS是最经济合理的钨钼分离新试剂.考察了试剂用量、反应温度和溶液pH值对除钼效果的影响,并获得了最佳除钼工艺条件,即在CuS试剂用量为理论量的3～4倍、室温下搅拌反应1h的条件下,可使溶液中的Mo从0.6～0.77g/L降至0.007～0.02g/L,除钼率达96.0%～98.5%,整个除钼过程中钨的回收率达99.75%以上.     

Heterogeneous electrochemical characteristics of biofilm/metal interface and local electrochemical techniques used for this purpose

Biofilms on metal surface in an aqueous environment is a complex electrochemical system. The heterogeneous electrochemical characteristics of biofilm/metal interface and local electrochemical techniques used for this purpose are discussed in this work. The techniques presented in this work include microelectrode, scanning vibrating electrode, the wire beam electrode method, and scanning electrochemical microscopy. Two potentially useful techniques, localized electrochemical impedance spectroscopy and scanning Kelvin probe force microscopy, are also discussed. The advantages and limitations of these techniques are summarized. A new approach: numerical simulation of micro‐electrochemical heterogeneity of biofilm covered metals is introduced.     

An electrochemical investigation on collectorless flotation of sphalerite in presence of Cu~(2 ) ions

1　ＩＮＴＲＯＤＵＣＴＩＯＮＲｅａｃｔｉｏｎｓｂｅｔｗｅｅｎｓｐｈａｌｅｒｉｔｅｓｕｒｆａｃｅａｎｄｃｏｐｐｅｒｉｏｎａｎｄｔｈｅｓｕｂｓｅｑｕｅｎｔＣｕ ｘａｎｔｈａｔｅｉｎｔｅｒａｃｔｉｏｎｈａｖｅｂｅｅｎｒｅｐｏｒｔｅｄｅｘｔｅｎｓｉｖｅｌｙ .ＡｌｔｈｏｕｇｈｔｈｅｓｕｒｆａｃｅｓｐｅｃｉｅｓｆｏｒｍｅｄｄｕｒｉｎｇｔｈｅＣｕｉｏｎａｃｔｉｖａｔｉｏｎｃａｎｂｅｅｘ ａｍｉｎｅｄｂｙｍａｎｙｔｅｃｈｎｉｑｕｅｓ (ＸＰＳ ,ＸＡＳ ,ＵＶ ,ＩＲ) ,ｔｈｅｙａｒｅｓｔｉｌｌａｍａｔｔｅｒｏｆｄｅｂａｔ…     

An electrochemical study of the corrosion behaviour of metals in canola biodiesel

The corrosion behaviour of pure Al, Cu, 1018 carbon steel and 304 type stainless steel in Canola biodiesel during 528 hours has been evaluated by using electrochemical techniques. Techniques include open circuit potentials (OCP), electrochemical noise (EN) and electrochemical impedance spectroscopy (EIS) measurements at room temperature. These tests were complemented by scanning electronic microscopy, X-ray diffraction, infrared spectroscopy and gas mass chromatography analysis. Results have shown that carbon steel had the highest corrosion rate whereas Cu had the lowest corrosion rate. EN measurements indicated that 304 type stainless steel was moderately susceptible to pitting corrosion, whereas the rest of the metals were susceptible to either mixed or uniform type of corrosion. This was due to the degradation of the biodiesel as observed in an increase in its density, viscosity, acidity and water content at the end of the test.     

The thermochemistry of transition metal sulfides

A survey is made of the available data for the standard Gibbs energies of formation of solid and liquid sulfides of transition metals. The results are plotted as standard Gibbs energy vs temperature diagrams. The equations and estimated accuracy are quoted for each substance.Supported by a Glunz Fellowship from the Ohio State University.     

钛合金脉冲电化学光整加工工艺研究

阐述了脉冲电化学抛光的基本原理。采用以甲酰胺(HCONH2)为基的非水电解液，在实验的基础上，初步分析了脉冲电流密度、脉冲宽度、脉冲占空比对光整加工质量的影响，获得了较为合理的工艺参数。     

Effect of electrochemical reactions droplet metal in direct current on oxygen contamination of submerged arc welding

Agglomerated fluxes with different basicity index designed in laboratory were used to study electrochemical reactions between slag and metal in submerged arc welding under both power polarities. The droplet metal oxygen and nitrogen contents were measured using oxygen-nitrogen instrument in order to analyze indirectly metallurgy electrochemical reactions taking place in cathode and anode of welding arc. The results show that just in the period of droplet growth at the tip of consumable electrode the electrochemical oxygen contamination is produced in the case of direct current electrode positive polarity whereas electrochemical oxygen lost in electrode negative polarity. Furthermore, the results indicate that the basicity index of molten slag has great influence upon electrochemical reaction. With basicity index increasing, the effect of oxygen transferring resulted from electrochemistry becomes more evident for reacting dynamics depended on ion characteristics of molten slag. The effect of basicity index on metal-slag electrochemical reaction is contrary to traditional thermo-chemical reaction and therefore it is necessary to be considered as a metallurgy factor.     

金属磷化物的球磨合成及电化学嵌脱锂研究

采用高能球磨技术分别合成了磷化钴、磷化铁和钴-铁-磷(Co-Fe-P)三元复合体.X射线衍射(XRD)分析结果表明,磷化钴主要是CoP3相,磷化铁为FeP和FeP2二相混合物,而三元复合体主要包含CoP3、FeP和FeP2 3相.材料的电化学嵌脱锂性能测试表明:磷化钴首次嵌锂容量为1 359 mA·h·g-1,电荷效率为70%;磷化铁首次嵌锂容量为901 mA·h·g-1,电荷效率为73%.而嵌锂容量居中(1 050 mA·h·g-1)的Co-Fe-P三元复合体具有最强的循环稳定性,10次循环以后,可逆容量保持在430 mA·h·g-1以上.     

电化学作用对直流焊接熔滴金属致氧量的影响

在对熔滴金属电化学致氧动力学分析基础上,用试验室自行设计制作的不同碱度系列烧结焊剂,采用在水冷铜板表面进行快速直流埋弧焊接方法提取出无熔池熔滴金属,以获取出熔滴金属质量几何信息并进而进行冶金电化学致氧量分析.结果表明,随着熔渣碱度的增大,钢-渣界面电化学作用愈加强烈,冶金电化学致氧量也愈加突出.就所研究CaO-Al2O3-SiO2渣系而言,当碱度值增至1.52时,冶金电化学致氧程度几乎可以达到与冶金热化学相当的程度,因而在直流焊接工艺制订及高碱度焊接材料研制中是一不可忽视的冶金致氧因素.     

2344模具钢的脉冲电化学复合光整加工试验研究

为了对2344模具钢进行快速光整加工,进行了2344模具钢的脉冲电化学复合光整加工试验研究。在构建了脉冲电化学复合加工试验机的基础上,进行了正交工艺试验。分析了脉冲峰值电压、脉冲频率、脉冲占空比和电解液温度对光整加工质量的影响,获得了优化的工艺参数。实验表明,在半个小时内可以将试件的表面粗糙度从Ra1.8μm降到Ra0.12μm。     

Electrochemical flotation separation of chalcopyrite from molybdenite by CM Eh control

1　ＩＮＴＲＯＤＵＣＴＩＯＮＭｏｌｙｂｄｅｎｉｔｅｉｓｏｆｇｏｏｄｎａｔｕｒａｌｆｌｏａｔａｂｉｌｉｔｙ ,ａｎｄｉｓｎｏｔｄｅｐｒｅｓｓｅｄｉｎａｗｉｄｅｐｏｔｅｎｔｉａｌｒａｎｇｅ (- 1.2～1.4Ｖ) [1] .Ｏｎｔｈｅｏｔｈｅｒｓｉｄｅ ,ｔｈｅｆｌｏａｔａｂｉｌｉｔｙｏｆｃｈａｌ ｃｏｐｙｒｉｔｅｉｓｄｅｃｒｅａｓｅｄｑｕｉｃｋｌｙａｔａｐｒｏｐｅｒｒｅｄｕｃｔｉｖｅｐｏ ｔｅｎｔｉａｌ.Ｔｈｅｒｅｆｏｒｅ ,ａｔｌｏｗｐｏｔｅｎｔｉａｌ,ｃｈａｌｃｏｐｙｒｉｔｅｃａｎｂｅｄｅｐｒｅｓｓｅｄａｎｄｍｏｌｙｂ…     

Electrochemical study of stainless steels used in an oil company by electrochemical impedance

Localized corrosion is a serious problem for stainless steel exposed in a chloride solution. In this context, the present work concerns the study of electrochemical behavior of 316 (A and B) and 430 (C and D) stainless steels, where A and C are laboratory steels, while steels B and D were taken from heat exchangers tubes (after 10 years of operation). This study has addressed three different aqueous environments: (1) monoethanolamine (MEA) 15%, (2) natural seawater (NSW), and (3) NaCl 3%, using the technique of potentiodynamic polarization curve complemented by electrochemical impedance spectroscopy (EIS). The obtained experimental electrochemical parameters (E_corr, J_corr, E_r, C_d, R_tc, and constant phase element) were used to compare the corrosion resistance of the tested steels. As a result, the nobility of these steels in NaCl 3% and in MEA 15% solutions is established in the following order: 316 (A) > 316 (B) > 430 (C) > 430 (D), where E_r moves increasingly toward the positive direction, indicating a good protection against corrosion. In addition, the results show that the effect of the electrolyte (aggression) is characterized by increased corrosion potential and a decrease in the passivity domain for all samples. The hierarchy of the nobility of steels A and C in these electrolytes can be determined as follows: MEA 15% > NSW > NaCl 3%.     

A comparative study of the corrosion stability of dental amalgams with electrochemical impedance measurements

The corrosion susceptibility of a selection of amalgams used in dentistry has been examined with the electrochemical impedance method. The results are compared with data derived from cyclic voltammetry performed with these materials before. Most examined materials including a conventional amalgam show similar corrosion resistance; however, only one product shows a significantly higher corrosion resistance.     

硫化矿物表面天然疏水性的密度泛函理论研究(英文)

采用密度泛函理论研究了水在硫化矿物表面的吸附以及硫化矿物的天然可浮性。为了排除氧气和其他因素的影响,所有的计算模型都是在真空环境下建立的。水分子是在黄铁矿与闪锌矿的表面,而不是在水里。对于方铅矿、辉铜矿、辉锑矿和辉钼矿,水分子是在水里,而不是在这些矿的表面。另一方面,黄铁矿表面亲氮气而不亲水,而闪锌矿表面不能吸附水。结果表明,方铅矿、辉锑矿、辉铜矿及辉钼矿是疏水的,而闪锌矿是亲水的。黄铁矿具有一定的亲水性,但是它更倾向于亲气,这是因为黄铁矿与水的作用要比与氮气的作用弱。因此,黄铁矿、方铅矿、辉铜矿、辉锑矿及辉钼矿都具有天然可浮性。     

掺杂金属对天然鳞片石墨电化学嵌/脱锂性能的影响

研究化学镀Ni、Cu和混合掺杂Zn处理后天然鳞片石墨的电化学嵌/脱锂性能。结果表明:金属微粒Ni、Cu与Zn的掺入可有效改善天然鳞片石墨的循环性能与大倍率充放电特性,金属微粒有效降低石墨电极内阻、保证石墨颗粒之间紧密的电接触是掺入金属微粒后石墨大倍率充放电性能得到改善的重要原因之一。Ni与Cu微粒改善石墨循环性能的机理与Zn的不同,Cu、Ni通过阻止溶剂化锂离子嵌入维持石墨结构稳定性,来达到提高材料循环性能的目的;金属Zn改善石墨循环性能的原因则可能是嵌锂过程中,Zn锂化所形成Li-Zn合金维持材料表面所形成SEI膜的稳定性。