Collector matching in origin potential flotation

Through thermodynamic calculation and electrochemistry analysis~ taking the galena as example,the ba-sis for collector matching in origin potential flotation (OPF) was studied. The results of thermodynamic calculation show that the upper limit value of pH and flotation potential of diethyldithiocarbamate (DDTC) is higher than that of xanthogenate (KBX), which indicates that the collecting ability of DDTC for galena is better than that of KBX.The results of the interface capacitance analysis show that lead diethyldithiocarbamate (PbD2) is more steady than lead xanthogenate (Pb(BX)2) on the galena surface under the oxidation condition; the resistance analysis shows thatD2 (DDTC oxidizes into its dimmer) and dixanthogen (BX)2 will occur non-faradic desorption on the pyrite electrodesurface when the potentials are above 0.13 V and 0.2 V respectively. A synthetical criterion ΔE of collecting ability and selectivity was proposed. The results predicted by this criterion are confirmed through flotation experiments of ore.     

Technological condition in slurry electrolysis of high-silver galena concentrate

Effects of various technological conditions such as ρ(C1^- ), ρ(Fe)T, pH value and temperature on the cell voltage, lead leaching rate and the cathodic current efficiency of the slurry electrolysis of high-silver galena concentrate were studied, and the behavior regularity of lead and silver was investigated. As a result, the suitable condition was determinedas, ρ(C1^-)230g/L, ρ(Fe)T15g/L, pH 1, temperature 70℃, electrolysis time 6h. Under such condition,adopting the cathodic current density of 150 A/m2 and the liquid-solid ratio of 15 : 1, lead powder with a purity degree of 91. 18% was got. At the same time, leaching rate of lead, leaching rate of silver and cathodic current efficiency amounted to 96.88%, 70.88% and 75.68% respectively.     

方铅矿的直接还原研究SCIEI

在873—973K的温度范围内研究了方铅矿的氢还原反应·结果表明,反应比较彻底,其规律可用在化学控制区的收缩核模型描述.还原反应为氢浓度的一级反应,活化能为79.0kJ/mol.试样的SEM二次电子图象表明,因液态 Pb与固态方铅矿间的界面张力很大,反应过程中在方铅矿表面难以形成Pb的液膜。     

Physical chemistry mechanisms of CDR system in sulphide mineral flotation

The flotation tests,zeta potential measurements,and Fourier transform infrared spectroscopy(FTIR) analysis on galena,sphalerite,and pyrite were studied in a collecting-depressing-reactivating(CDR) system.In this system,sulphide minerals were first collected and acti-vated by the collector,and then depressed strongly by Ca(OH)2 in a strong alkaline solution.Finally,they were reactivated by H2SO4.The flotation tests of pure minerals showed that in the Ca(OH)2 depressing process sulphide minerals had similar flotation characteristics because they had already been influenced by the collector.Hence,the flotability differences between them were reduced.However,in the H2SO4 re-activating process considerable differences in the flotability between galena and sphalerite/pyrite were produced.That is to say,galena was relatively easy to be reactivated by H2SO4,but sphalerite and pyrite were not reactivated at pH 11.The zeta potentials of sulfide minerals measured by the Zeta Plus presented irreversible characteristics on the change of pH values.The results of the FTIR spectra analysis indi-cated that the collectors already adsorbed on the mineral surface were removed partially by Ca(OH)2.     

国外某复杂低品位铅锌矿选矿工艺优化及应用

某铅锌矿原矿铅含量为1.26%,含锌6.53%,含硫30.38%。生产上采用“铅锌依次优先浮选-中矿顺序返回”工艺流程,生产指标为铅精矿铅品位50.69%,含锌12.61%,铅回收率75.53%,锌精矿锌品位48.77%,含铅1.59%,锌回收率73.91%。铅锌互含较高,锌精矿指标不理想。为了解决该问题,本文在了解现场生产工艺流程及矿石性质的基础上,针对该铅锌矿开展了详细的选矿工艺优化试验,通过对部分药剂制度进行优化,采用特效捕收剂BK-LY11,同时在锌浮选回路采用中矿再磨工艺,显著改善了铅锌互含情况,有效提高了铅锌选别指标,并成功应用于生产实践,优化后获得的铅、锌回收率分别提高了5.83、8.46个百分点。     

Galena-pyrolusite co-extraction in sodium chloride solution and its electrochemical analysis

The co-extraction behavior of galena-pyrolusite in a sodium chloride solution and the electrochemical mechanism of this process were investigated, and some factors affecting the leaching rate of Pb and Mn were optimized. The results show that all the factors such as the concentration of NaCl, HCl and pyrolusite ore, reaction time, temperature, adding times of HCl, affect the leaching rate of Pb. The main affecting factors are the concentration of NaCl, reaction time and temperature. The Tafel polarization curves and EIS plots of the galena and pyrolusite in the NaCl solution demonstrate that during the oxidation process of galena mineral electrode, film forms on the galena surface, which prevents galena from deeper oxidation. However, the film resistance can be greatly reduced in the presence of sodium chloride, thus promoting the reaction rate of galena.     

Kinetics of electrochemical process of galena electrode in diethyldithiocarbamate solution

1　ＩＮＴＲＯＤＵＣＴＩＯＮＤｉｅｔｈｙｌｄｉｔｈｉｏｃａｒｂａｍａｔｅ (ＤＤＴＣ)ｉｓｏｎｅｏｆｔｈｅｍｏｓｔｆｒｅｑｕｅｎｔｌｙｕｓｅｄｃｏｌｌｅｃｔｏｒｓｆｏｒｆｌｏｔａｔｉｏｎｏｆｈｅａｖｙ ｍｅｔａｌｓｕｌｆｉｄｅｍｉｎｅｒａｌｓ ,ｓｕｃｈａｓｇａｌｅｎａ ,ｃｈａｌｃｏｐｙｒｉｔｅａｎｄｊａｍｅｓｏｎｉｔｅ ,ａｎｄｉｔｓｈｏｗｓｓｔｒｏｎｇｓｅｌｅｃｔｉｖｉｔｙ[1] .ＷｈｅｎＤＤＴＣｗａｓｕｓｅｄｉｎｈｉｇｈｌｙａｌｋａｌｉｎｅ (ｐＨ >11.4 )ｆｏｒｓｅｐａｒａｔｉｎｇｇａｌｅｎａｆｒｏｍｓ…     

综合回收锌矿石中伴生低品位铜铅工艺研究

某锌矿石中伴生有铜、铅等矿物,其中锌品位为3.29%、铅品位为0.084%、铜品位为0.11%,为原生硫化矿石。根据矿石性质采用铜铅混合浮选—铜铅分离—锌浮选的工艺流程,进行了小型试验和工业试验,采用BK510抑铜浮铅工艺,工业试验指标与原重铬酸钾工艺流程指标比较,铅精矿品位由38.08%提高到60.59%,铅回收率由30%提高到45.20%,铜精矿品位由20%提高到21.43%,铜回收率由34%提高到40.04%,获得可观的经济效益。     

Correlation between surface free energy and floatability of galena with potassium ethyl xanthate

From the maximal extrapolated film pressure π_max values for n-octane and n-propanol, the dispersion and non-dispersion components of the surface free energy of galena precoated with potassium ethyl xanthate (collector) were estimated and they were then correlated with the floatability of galena. The collector layer deposited by methanol evaporation did not produce any significant changes in the surface free energy of galena. Polymolecular adsorption of the collector occurred from aqueous solution. The adsorbed collector layer of ~8 statistical monolayers in thickness produced a considerable decrease in the dispersion component of the surface free energy and complete disappearance of non-dispersion interactions. At this surface coverage, a certain change in the properties of the adsorbed layer appeared which was probably connected with the formation of polymolecular layers containing dixanthogen. The work of the water adhesion being significantly lower than the work of water cohesion appeared insufficient to achieve a high floatability of galena.     

低硫铅锌矿选矿工艺的研究

某硫化铅锌矿含铅8.79%，含锌13.24%,采用一段磨矿（细度73％－0.075mm）、选浮铅、中矿循序返回的优元宵服选流程及混合捕收剂乙、丁黄药和SN－9,得到：铅精矿品位71.55%,回收率91.89%；锌精矿品位50.34%，回收率85.38%，并综合回收了伴生的镉、银。