Electrochemical flotation of ethyl xanthate-pyrrhotite system

1　INTRODUCTIONPyrrhotite(Fe1-xS ,0 相似文献   

Electrochemical flotation separation of marmatite from pyrrhotite in the presence of copper ion

1　ＩＮＴＲＯＤＵＣＴＩＯＮＷｉｔｈｔｈｅｄｅｖｅｌｏｐｍｅｎｔｏｆｆｌｏｔａｔｉｏｎ ｐｒｏｃｅｓｓｆｏｒｂｅｎｅｆｉｃｉａｔｉｏｎｏｆｓｕｌｆｉｄｅｍｉｎｅｒａｌｓｗｉｔｈｘａｎｔｈａｔｅａｓｃｏｌ ｌｅｃｔｏｒ ,ｍａｎｙｓｔｕｄｉｅｓｈａｖｅｂｅｅｎｍａｄｅｉｎｅｆｆｏｒｔｓｔｏｉｍ ｐｒｏｖｅ ,ｃｏｎｔｒｏｌａｎｄｕｎｄｅｒｓｔａｎｄｆｌｏｔａｔｉｏｎ ｐｒｏｃｅｓｓ .Ｆｒｏｍｔｈｅｓｅｉｎｖｅｓｔｉｇａｔｉｏｎｓ ,ｉｔｉｓｇｅｎｅｒａｌｌｙｂｅｌｉｅｖｅｄｔｈａｔｔｈｅｏｘｉｄａｔｉｏｎｏ…     

Electrodeposition of dixanthogen（TETD） on pyrite surface

The electrochemical reaction of xanthate on the surface of pyrite was studied using cyclic voltammogrametry, chronopotentiometry and rotating-disc electrode measurements.Experimental results demonstrate that the first step in the reaction is electrochemical adsorption of xanthate ion,and then the adsorbed ion associates with a xanthate ion from the solution and forms a dixanthogen on the pyrite electrode surface.The diffusion coefficient of butyl xanthate on pyrite electrode surface can be determined to be about 1.09×10- 6cm2/s.Using the galvanostatic technique,the kinetic parameters of oxidation of the butyl xanthate ion on the pyrite surface are calculated as Ja=200μA/cm2 ,β=0.203 and J0=27.1μA/cm2.     

Electrochemical characteristics of couple electrode of galena-pyrite in different solutions

1　ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｅｌｅｃｔｒｏｃｈｅｍｉｓｔｒｙｐｌａｙｓａｎｉｍｐｏｒｔａｎｔｒｏｌｅｏｎｔｈｅｆｌｏｔａｔｉｏｎｏｆｓｕｌｆｉｄｅｍｉｎｅｒａｌｓ .Ｅｘｔｅｎｓｉｖｅｒｅｓｅａｒｃｈｈａｓｄｅｍｏｎｓｔｒａｔｅｄｔｈａｔｔｈｅｆｌｏｔａｔｉｏｎｏｆｓｕｌｆｉｄｅｍｉｎｅｒａｌｄｅｐｅｎｄｓｓｔｒｏｎｇｌｙｏｎｔｈｅｏｘｉｄａｔｉｏｎｐｏｔｅｎｔｉａｌｉｎｔｈｅｅｎ ｖｉｒｏｎｍｅｎｔｓｕｒｒｏｕｎｄｉｎｇｓ[1～ 4 ] .Ｃｏｎｔｒｏｌｌｉｎｇｔｈｅｅｌｅｃｔｒｏ ｃｈｅｍｉｃａｌ…     

电化学调控浮选能带模型及应用(Ⅱ)——黄药与硫化矿物作用的能带模型

用能带模型研究了黄药与硫化矿物的作用机理 ,说明了硫化矿物表面捕收剂膜的稳定性与半导体能带结构的关系 ,并推导出黄铁矿Barsky关系式。对矿物表面双黄药解吸作用的研究 ,表明矿物表面双黄药的解吸主要受控于矿物电子能级 ,而半导体矿物边缘能级和费米能级影响矿物表面双黄药的稳定性 ,改变硫化矿物的费米能级或边缘能级可以实现双黄药的解吸。根据电化学浮选抑制的能带模型 ,可开发出高效硫化矿有机抑制剂。     

电化学调控浮选能带模型及应用(Ⅲ)——有机抑制剂对硫化矿物能带结构的影响

用能带理论分析了电化学调控浮选模型 ,提出了采用有机抑制剂来改变矿物电子能级、实现硫化矿的浮选分离。研究了有机抑制剂对矿物抑制的两种电化学机理 :一是有机抑制剂增加了矿物费米能级 ,矿物电子向黄药的空能级传递 ,双黄药被还原 ;二是有机抑制剂降低了矿物边缘能级 ,从而导致矿物表面电子密度增大 ,黄药空能级被电子占据 ,双黄药被还原。开发了 5种电化学浮选分离新型有机抑制剂 ,实现了 8种人工混合精矿和3种矿石的浮选分离。     

锌阳极泥矿浆中铅银矿物的赋存状态及其与黄药的作用(英文)

用热力学方法分析锌阳极泥矿浆的强氧化背景矿浆电位及其对铅、银和黄原酸盐赋存状态的影响。结果表明,在强氧化背景矿浆电位下,铅以 Pb2+或 PbSO4形式存在,银以金属银、AgCl 和 Ag2O 等形式存在,黄原酸盐以其氧化后的二聚物双黄药形式存在。XRD 分析结果表明,锌阳极泥中的铅矿物主要是铅矾,主要的银矿物之一是氯银矿。单矿物浮选实验表明,双黄药对氯银矿的捕收力远强于对铅矾的。用 Material Studio(Adsorption Locater)模块计算了两种吸附质(铅矾和氯银矿)与不同吸附剂(双黄药, H2O, OH-, Cl-, SO42-)的作用能变化。结果表明,在存在 SO42-的条件下,双黄药只能吸附在氯银矿表面。红外光谱测试证实了双黄药对氯银矿的选择性吸附作用。     

Adsorption behavior of heptyl xanthate on surface of ZnO and Cu(II) activated ZnO using continuous online in situ ATR-FTIR technology

A continuous online in situ attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopic technique was used to investigate the adsorption and desorption kinetics of heptyl xanthate (KHX) on the surface of ZnO and Cu(II) activated ZnO. The results showed that Cu(II) facilitated the xanthate adsorption process on the surface, and led to the formation of cuprous xanthate (CuX), dixanthogen (X₂) and xanthate aggregates. The adsorption of xanthate on the surface of ZnO and Cu(II) activated ZnO was found to both follow the pseudo-first-order kinetic model. When the NaOH solution was used as a desorption agent, the adsorbed xanthate can largely be removed due to the competition between OH^? and HX^?. However, for Cu(II) activated ZnO, the peak intensities at 1197 and 1082 cm^?1 had no obvious weakening, and the absorption intensities at 1261 and 1026 cm^?1 increased in the first 5 min, indicating an ion-exchange reaction between OH^? and surface zinc bonded xanthate HX^? and the reorganization of adsorbed xanthate.     

电位对天然黄铜矿表面膜层性质的影响

采用循环伏安（CV）、扫描电子显微镜（SEM）和电化学阻抗谱（EIS）研究黄铜矿在含有5×10-4mol/L乙黄药溶液中的电化学行为以及电位对黄铜矿表面膜层成分和性质的影响。结果表明：在开路电位（OCP）下,天然黄铜矿表面发生黄药阴离子的吸附过程;在阳极电位范围-0.11～0.2V内,主要发生黄药阴离子氧化形成疏水双黄药膜层的电化学过程。形成的双黄药膜层在电位为0V时具有较高覆盖度和较大的厚度,随着电位的增加表面双黄药膜层的覆盖度和厚度减小。当电位高于0.2V时,黄铜矿表面发生以自身活化溶解为主的电化学过程,黄铜矿表面由双黄药膜层转化成为大量具有多孔和疏松结构的含有Cu（Ⅱ）和Fe（Ⅲ）的氧化物。     

Electrochemical oxidation of pyrrhotute in aqueous solution

The anodic surface oxidation of natural pyrrhotite in 0.3 mol/L KCI and HCI solution （pH 4.0） and 0.1 mol/L Na2B4O7 solution （pH 9.18） respectively was investigated by using cyclic voltammetry, Tafel plot, and chronoamperometry. In 0.3 mol/L KCl and HCl solution （pH 4.0）, at potential less than 0.5 V（vs SHE）, the production of anodic oxidation on pyrrhotite surface can not maintain a stable phase to form a passive film. In 0.1 mol/L Na2B4O7 solution （pH 9.18）, when the electrode potential increases to more than 0.5 V （vs SHE）, part of S is oxidized to sulfate, making the passive film somewhat porous, but elemental S and metal oxidates Fe（OH）3 still remain on the electrode surface, and the passive film can not be broken down totally. According to PARCalc Tafel analysis, the corresponding corrosion current density （J0） is 5.34 μA/cm^2 , which is also the exchange current density of the oxidation reaction on pyrrhotite electrode surface in 0. 1 mol/L Na2B4O7 solution （pH 9. 18）. The electrochemical dynamics equation of the oxidation was determined.     

Mechanism of sodium sulfide on flotation of cyanide-depressed pyrite

The mechanism of sodium sulfide (Na₂S) on the flotation of cyanide-depressed pyrite using potassium amyl xanthate (PAX) as collector was investigated by flotation test and electrochemical measurements. The flotation results show that both PAX and Na₂S can promote the flotation recovery of cyanide-depressed pyrite and their combination can further improve the pyrite flotation recovery. Electrochemical measurements show that PAX and Na₂S interacted with cyanide-depressed pyrite through different mechanisms. PAX competed with cyanide and was adsorbed on the pyrite surface in the form of dixanthogen, thus enhancing the hydrophobicity and flotation of cyanide-depressed pyrite. Unlike PAX, Na₂S rendered the pyrite surface hydrophobic through the reduction of ferricyanide species and the formation of elemental sulfur S⁰ and polysulfide. The combined application of PAX and Na₂S induced superior pyrite flotation recovery because of a synergistic effect between PAX and Na₂S.     

铱金属氧化物pH电极的表面修饰研究

采用离子选择性透过膜对铱金属氧化物pH电极进行表面修饰，提高了氧化物pH电极对氧化／还原性阴离子的抗干扰能力；研究了离子选择性透过膜修饰对电极的E-pH关系以及响应速度的影响；利用扫描电镜观察离子选择性透过膜的表面与截面孔径分布，优化了离子选择性膜的制备工艺；利用循环伏安法研究了氧化物电极在I^-溶液中的电化学行为；利用膜电位测定方法计算了膜内阴、阳离子透过系数t＋，t-，探讨了离子选择性透过机理。     

CO2环境下温度和S2-对X60管线钢电化学行为的影响

利用极化曲线和电化学阻抗测试研究了温度和硫离子对X60管线钢CO2腐蚀电化学行为的影响。结果表明,在温度和硫离子交互作用下,随温度的升高腐蚀电流密度不断增大。S2-加入后电极表面生成一层黑色的腐蚀产物膜,随着S2-浓度的升高,腐蚀电位明显负移,腐蚀电流密度呈现下降-上升-下降的趋势,电极过程主要受硫化物生长过程控制。     

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…     

Flotation separation of marmatite from pyrrhotite using DMPS as depressant

1 Introduction Pyrrhotite and marmatite are found in most sulfide ore bodies together. Their separation becomes an important issue. In the flotation of complex sulfide ores, high pH value is generally used to separate valuable sulfide minerals from pyrrh…     

酸性溶液中不同电位下脆硫锑铅矿/DDTC界面的电化学机制

用循环伏安和交流阻抗法,研究了脆硫锑铅矿在含乙硫氮的pH 4.0缓冲溶液中的表面电化学行为,讨论了在不同电位下脆硫锑铅矿表面的反应、电化学吸附、钝化作用、电化学阻抗、微分电容的变化.结果表明:在酸性溶液中,脆硫锑铅矿具有盐的特性;电极过程呈现出受电化学反应及产物吸附控制的动力学特征.当电极电位为-78 mV～422 mV,矿物表面疏水性膜逐渐增长并产生钝化作用;当电极电位为522 mV时,电极过程完全由离子扩散决定的电化学反应所控制;当电位大于622 mV后,电极反应产生大量的PbSO4沉淀,并覆盖在电极表面,矿物表面的亲水性强.     

氨性溶液中砷黄铁矿阳极氧化过程的电化学

通过电化学研究 ,考察了氨溶液中砷黄铁矿的阳极氧化反应。实验表明氧化生成的表面膜对反应有抑制作用 ,该膜具有多孔性 ,可使反应继续进行。低温时 ,阳极氧化过程由电化学反应控制 ;高温时 ,反应受扩散过程控制。氨浓度对氧化过程的反应速率没有显著影响 ,溶液中Cu2 能降低氧化峰电位 ,改变氧化表面膜的形态 ,使膜的孔隙增大 ,反应速度加快。砷黄铁矿的阳极氧化总反应为FeAsS 11H2 O =Fe(OH) 3 SO2 -4 HAsO2 -4 18H 14e。     

锡电极嵌锂过程的交流阻抗谱

采用交流阻抗谱研究锡电极的首次嵌锂和第二次嵌锂过程,对比锡纳米阵列电极、锡薄膜电极和锡箔3种不同材料微观结构对电极交流阻抗谱特征的影响。用等效电路模型分析交流阻抗谱,得到嵌锂过程电化学特征参数与电位关系。结果表明:锡纳米阵列电极与锡薄膜、锡箔电极具有不同交流阻抗谱特征,锡纳米阵列电极在中频区出现双电层阻抗;首次嵌锂时在1.6~0.8 V之间形成固体电解质膜(SEI);电极材料微观结构显著影响锡电极的SEI膜电阻、Warburg阻抗和锂离子扩散速率;锡纳米阵列电极上的SEI膜电阻和Warburg阻抗最小,锂离子扩散能力最强;锡纳米阵列电极上锂的扩散系数为4.4×10-15~1.4×10-11 cm2/s;锂扩散系数随电位变化显著。     

碳化混凝土再碱化过程中钢筋在Ca（OH）2溶液中的电极过程

研究了碳化混凝土再碱化过程中钢筋在Ca(OH)2溶液中的电极表面电化学反应,采用电化学测量技术结合模拟试验考察了电极表面发生各类反应的可能性.结果表明:再碱化过程中,钢筋电极表面的电化学反应与钢筋表面的状态有密切关系,当电极表面存在锈蚀层时,再碱化过程析氢反应和氧化铁的还原同时发生,并使表面氧化层的价态逐渐降低,在电极表面形成金属铁,析氢过程产生的OH-使钢筋周围混凝土的碱性提高.     

金属在流动氯化物体系中流动腐蚀的EIS研究

流动氯化物体系中碳钢、双相钢电极的电化学阻抗谱（EIS）明显不同,随着流速增大,电极表面受到的切应力增大,反应阻抗减小,电化学腐蚀加速,协同效应增强,结果使电极流动腐蚀速度增加,与碳钢相比,双相钢电极在较高流速下其电化学阻抗谱才在低频区发生特征变化,证明了曹楚南提出的不可逆电极阻抗谱理论同样适用于流动腐蚀过程中电极过程的研究,揭示了在流动体系中,当电极表面受到足够大的切应力作用时,在低频区电极电化学阻抗谱会发生特征改变,其中,电化学阻抗谱的低频感抗弧特征预示着在流动腐蚀过程中,受到强力流体力学作用的电极表面会改变其常规的溶解速度和溶解机制,同时表面伴随有坑、点局部腐蚀的发生,在此情况下,钝态金属电极的电化学阻抗谱进一步反映了电极表面受到固体颗粒摩擦或撞击的阻抗谱特征。