都龙锡矿区铅矿化特征及其实际意义

都龙矿区的锡矿化与铅矿化既有成因联系,又有重要的区别,前者属岩控型高温热液矿床,后者为层控型热液矿床.田蓬组第四岩性段是形成铅矿床的主要矿源层,尽管部分铅可能来自燕山期花岗岩.铅矿化不仅具有工业意义,而且可作为寻找锡矿体的指示元素。

内蒙古巴林左旗老毕家营子H_Z-10化探异常地质特征及查证效果

HZ-10异常是内蒙古巴林左旗乌尔吉等四幅1∶5万矿产调查项目中圈定的一处重要异常,为查明异常,内蒙古地质勘查基金立项,采用1∶1万地质、土壤、激电面积测量,配合1∶5000地、物、化综合剖面测量、激电测深查证,经查证HZ-10异常浓集强度较高,浓集中心明显,各元素相互重叠,梯度较大,具明显矿致异常特征。激电异常IP1呈现高极化(视极化率值5%~7.9%),低阻异常特征。地表蚀变带呈褐黑色、褐黄色褐铁矿矿化、伴硅化,探槽(TCⅠ401)揭露铅矿化体连续刻槽样长度7.10m,真厚度6.68m,伴生银铅锌矿化,推断HZ-10异常由金属硫化物引起,矿致异常清晰。

吉林省安图县三岔地区土壤异常特征与找矿前景

根据安图县三岔地区的土壤地球化学测量结果、R型聚类分析、相关性矩阵分析及优选异常查证,确定区内铅矿化体为受北西向张性断裂构造控制。土壤聚类分析表明,Au元素呈独立地球化学行为,Cu-Ag-Pb-Zn具有密切的相关性,代表了热液银、铅、锌等多金属异常元素组合,特别是Pb-Zn元素组合相关系数达0.5181,表明二者地球化学行为的相似性,暗示了两种元素内在共生组合关系的存在。优选Au、Ag、Pb异常进行了详细的查证,发现了一些Cu、Pb矿化体,预示了良好的找矿前景。

Electrochemical behavior of galena and jamesonite flotation in high alkaline pulp

In order to effectively separate galena and jamesonite and improve the recovery during the mixing flotation, the interaction mechanisms between the minerals and the collector of diethyl dithiocarbamate （DDTC） were investigated. Single mineral flotation test was organized to research the effect of pulp pH value on the flotation behavior of galena and jamesonite. Electrochemistry property of the interaction of these two minerals with DDTC was investigated by cyclic voltammetry and Tafel tests. Flotation test shows that the recovery of jamesonite in high alkaline pulp is strongly depressed by lime （Ca（OH）2）. The cyclic voltammetry and Tafel tests results show that the interaction between galena and DDTC is an electrochemical process. High pH value has little influence on the interaction between galena and DDTC, while it has great effect on jamesonite due to self-oxidation and specific adsorption of OH^- and CaOH^＋ on jamesonite surface. Non-electroactive hydroxyl compound and low-electroconductive calcium compounds cover the surface of jamesonite, which impedes electron transfer and DDTC adsorption, thus leads to very low floatability of jamesonite.

广东省连平县陂头铅锌多金属矿新坪区段找矿前景分析

矿区处于连平钨锡铅锌成矿远景区。区域构造发育,为成矿提供了有利通道和场所,成矿条件良好。新坪区段VⅡ-1铅锌多金属矿化体处于帽子峰组与天子岭组接触部位,对于形成铅锌多金属矿是良好的场所;VⅡ-2含铅锌钴矿化点位于帽子峰组地层中的褐铁矿带中,规模较大。该区域寻找铅锌多金属矿有较大潜力。

海丰县赤石明溪锡多金属矿区找矿前景分析

海丰县赤石明溪锡多金属矿区位于广东汕尾。矿区预查工作通过地质填图、地球化学测量及槽探揭露等技术手段,确定两处重点工作区。经槽探工程地表揭露,在老鸦山综合异常区揭露出两处铅矿(化)体,可作为下一步工作重点区域;上田心综合异常区实施少量槽探工程见矿情况较差,但该区域成矿信息良好,地质情况亦对成矿非常有利,下一步可通过槽探揭露、浅钻等手段进一步了解其矿化信息。本次工作对矿区的成矿条件进行了初步评价,取得了良好的找矿成果,为下一步找矿工作提供了依据。

Flotation behaviors and mechanisms of chalcopyrite and galena after cyanide treatment

Adsorbing tests between CN? and chalcopyrite or galena were conducted firstly, and then flotation tests of the twocyaniding minerals were investigated in butyl xanthate (BX) system. Results showed that the interaction between CN? and the twomineral surfaces were both chemical adsorption and can be described by the Langmuir adsorption isotherm model. In the optimumcondition of pH 6.5 and 4.0 mg/L BX, the recovery of cyaniding chalcopyrite and galena reached 82.1% and 63.9%, respectively. BXimproved the hydrophobicity of the surfaces of the two minerals, although CN? reduced the contact angle on the surface of minerals.The inhibitory effect of CN? on chalcopyrite far outweighed galena. Electrostatic adsorption exists in the interaction between BX andthe surface of galena after cyanide treatment in the pH range of 4.2?8.4, while the interactions between BX and the surface ofchalcopyrite after cyanide treatment is chemical adsorption.

Sulfidation mechanism of cerussite in the presence of sulphur at high temperatures

In this paper,sulfidation mechanism of cerussite in the presence of sulphur at high temperatures was investigated based on micro-flotation,X-ray powder diffractometry(XRD),electron probe microanalysis(EPMA)and X-ray photoelectron spectroscopy(XPS).The micro-flotation test results showed that flotation recovery of the treated cerussite increased to above 80%under a suitable flotation condition.It was found that the S/PbCO3 mole ratio and pH obviously affected flotation recovery.XRD analysis results confirmed that the cerussite was decomposed into massicot and then was transformed into mainly PbS and PbO·PbSO4 after sulfidation roasting.EPMA analysis results demonstrated that surface of the obtained massicot was smooth,but surface of the artificial galena was rough and even porous.Content of oxygen decreased,whereas content of sulphur increased with an increase in the S/PbCO3 mole ratio.XPS analysis results revealed that various lead-bearing species,including mainly PbS,PbSO4 and PbO·PbSO4,were generated at the surface.Formation of PbS was advantageous to flotation of the treated cerussite.Based on these results,a reaction model of the cerussite sulfurized with sulphur was proposed.

Potential control flotation of galena in strong alkaline media

The electrochemical oxidation of galena in collectorless and collector flotation systems, particularly in strong alkaline media, was studied. The results show that, with pH value higher than 12.5 and potentials below 0.17 V, the oxidation products of galena are elemental sulfur and HPbO - 2. Elemental sulfur was present on the mineral surface in excess of oxidized lead species due to dissolution of HPbO - 2, which is beneficial to the flotation of galena. Under the same conditions, sphalerite and pyrite were depressed as a result of significant surface oxidation. Diethyldithiocarbamate (DDTC) was found to be the most suitable collector for galena flotation in strongly alkaline media. The very potential produced hydrophobic PbD 2-the surface reaction product of DDTC with galena, is 0 to 0.2 V. Meantime DDTC can depress the surface over oxidation of galena. Investigations also indicate that, in the range of -0.9 V to 0.6 V, hydrophobic PbD 2 can be firmly adsorbed on galena.

Separation of sulfide lead-zinc-silver ore under low alkalinity condition

A complex lead-zinc-silver sulfide ore containing 2.98% Pb, 6.49% Zn and 116.32×10^-4 % Ag （mass fraction） from Yunnan Province, China, was subjected to this work. Research on mineral processing was conducted according to the properties of the lead-zinc-silver ore. Under low alkalinity condition, the lead minerals are successfully separated from the zinc minerals with new reagent YZN as zinc depressant, new reagent BPB as lead collector, CuSO4 as zinc activator and ethyl xanthate as zinc collector. The associated silver is mostly concentrated to the lead concentrate. With the process utilized in this work, a lead concentrate of 51.90% Pb with a recovery of 82.34% and a zinc concentrate of 56.96% Zn with a recovery of 81.98% are produced. The silver recovery in the lead concentrate is 80.61%. Interactions of flotation reagents with minerals were investigated, of which the results indicate that the presence of proper amount of Na2S can precipitate Pb^2＋ and has a sulfidation on oxidized lead minerals. The results also show that NazCO3 and YZN used together as combined depressants for sphalerite can signally improve the depressing effect of new reagent YZN on sphalerite.

Original potential flotation of galena and its industrial application

In the light of the knowledge gained by the study of electrochemical flotation for galena and selective flotation of galena from lead zinc iron sulfide ores, a technology for accurate potential control based on intrinsic electrochemical behavior in grinding flotation systems has been developed and is called "Original Potential Flotation (OPF)". The optimum conditions for the original potential flotation of galena from Pb Zn Fe sulfide ores are as follows: pH values of 12.5 12.8, potential of 150 180 mV and with diethyldithioncarbamate (DDTC) as collector. Lime is used as a regulator of pH, meanwhile, and can stabilize special potential very well, and this special potential is exactly the flotation potential of galena. This technology has been applied successfully in potential control flotation of galena in many complex lead zinc iron sulfide mines in China.

Electrochemical mechanism and flotation of chalcopyrite and galena in the presence of sodium silicate and sodium sulfite

The electrochemical mechanism involved in the selective separation of chalcopyrite from galena was investigated by flotation and electrochemical methods in the presence of sodium sulfite and sodium silicate,respectively,as a single depressant and their mixture as a combined depressant.Flotation tests revealed that the floatability of chalcopyrite was unaffected by depressants and its recovery remained constant(>80%)within the studied dosage range.Galena flotation was severely depressed with descending depressing order as follows:combined depressant﹥sodium silicate﹥sodium sulfite.Electrochemical analysis confirmed the high affinity of depressants on the galena surface,resulting in the formation of hydrophilic species,such as lead sulfite,lead sulfate,and lead orthosilicate.The oxidation of chalcopyrite surface and depressants did not exhibit any signals;conversely,the self-oxidation of chalcopyrite was depressed.The results of cyclic voltammograms well agreed with flotation results,demonstrating that chalcopyrite primarily reacted with the collector O-isopropyl-N-ethyl thionocarbamate and that galena mostly reacted with depressants.

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.

Sodium sulfide leaching of low-grade jamesonite concentrate in production of sodium pyroantimoniate

Sodium sulfide leaching of a low-grade jamesonite concentrate in the production of sodium pyroantimoniate through the air oxidation process and the influencing factors on the leaching rate of antimony were investigated. In order to decrease the consumption of sodium sulfide and increase the concentration of antimony in the leaching solution, two-stage leaching of jamesonite concentrate and combination leaching of high-grade stibnite concentrate and jamesonite concentrate were used. The experimental results show that the consumptions of sodium sulfide for the two-stage leaching process and the combination leaching process are decreased by 20% and 60% compared to those of one-stage leaching process respectively. The final concentrations of antimony in the leaching solutions of both processes are above 100g/L.

Effect of sodium pyrophosphate on the flotation separation of chalcopyrite from galena

The effect of sodium pyrophosphate （SPH） on the separation of chalcopyrite from galena was examined through flotation, adsorption, electrokinetic studies and infrared spectral analysis. Differential flotation tests indicate that satisfactory separation can be achieved within the pH range from 2.5 to 6 using SPH to depress the galena, but not the chalcopyrite when O-isopropyl-N-ethyl thionocarbamate （IPETC） is used as the collector. The electrophoretic mohilities of both the minerals dramatically become negatively charged following SPH adsorption in the pH range from 2.5 to 12, The infrared spectral analysis suggests that chemical adsorption occurs on galena surface treated by SPH, indicating that a chelate complex has formed. At weakly acidic pH values, the adsorption density of IPETC onto galena is significantly reduced in the presence of SPH. However, the amount of IPETC adsorbed onto chalcopyrite almost remains at the same level. Since the observed adsorption density of IEPTC onto chalcopyrite is quite high compared to galena, the observed flotation results are explained. A possible mechanism for the interaction between the two sulphide minerals and SPH is discussed.

Studies on Environmentally Friendly Leaching Processes in China

The newly developed green leaching processes for chromium, lead and gold extraction from ores or concentrates are described. The chromium is extracted from the iron chromite ore with fused sodium hydroxide at 500-550℃ as sodium chromate. The galena in lead sulfide concentrate is converted into lead carbonate in ammonium or sodium carbonate solution at 50-80℃ followed by the separation of lead carbonate formed from the unconverted sulfide ores by flotation. Gold associated with sulfide ore (such as pyrite and chalcopyrite) can be extracted into sodium thiosulfate solution without any pretreatment such as roasting, high pressure aqueous oxidation or bacteria pre-leaching.

Predictive GIS Model for Potential Mapping of Cu,Pb,Zn Mineralization

ABSTRACT The geologic features indicative of Cu, Pb, Zn mineral deposits in a area are fractures （structure）, and host rock sediments. Datasets used include Cu, Pb, Zn deposit points record, geological data, remote sensing imagery （Landsat TM5）. The mineral potential of the study area is assessed by means of GIS based geodata integration techniques for generating predictive maps. GIS predictive model for Cu, Pb, Zn potential was carried out in this study area （Weixi） using weight of evidence. The weights of evidence modeling techniques is the data driven method in which the spatial associations of the indicative geologic features with the known mineral occurrences in the area are quantified, and weights statistically assigned to the geologic features. The best predictive map generated by this method defines 24 % the area having potential for Cu, Pb, Zn mineralization further exploration work.

Effect of Fe/SiO2 and CaO/SiO2 mass ratios on metal recovery rate and metal content in slag in oxygen-enriched direct smelting of jamesonite concentrate

The oxygen-enriched direct smelting of jamesonite concentrate was carried out at 1250℃by changing the slag composition.The effects of Fe/SiO2 and Ca O/SiO2 mass ratios on the metal recovery rate as well as metal content in slag were investigated.Experimental results indicated that the metal(Pb+Sb)recovery rate was up to 88.30%,and metal(Pb+Sb)content in slag was below 1 wt.%under the condition of slag composition of 21-22 wt.%Fe,19-20 wt.%SiO2 and 17-18 wt.%Ca O with Fe/SiO2 mass ratio of 1.1:1 and Ca O/SiO2 mass ratio of 0.9:1.The microanalysis of the alloy and slag demonstrated that the main phases in the alloy contained metallic Pb,metallic Sb and a small amount of Cu2 Sb and Fe Sb2 intermetallic compounds.The slag was mainly composed of kirschsteinite and fayalite.Zinc in the raw material was mainly oxidized into the slag phase in the form of zinc oxide.

Molecular structures and activity of organic depressants for marmatite,jamesonite and pyrite flotation

Ten kinds of organic depressants were used to investigate the depressing performance on marmatite and pyrite.Flotation results show that the organic compounds only with single group of hydroxyl(-OH),carboxyl(-COOH) or amino(-NH2) in molecule are ineffective in depressing marmatite,jamesonite and pyrite.The combinations of these functional groups still cannot enhance the depressing ability of organic depressant.The thioglycollic acid containing reductive functional group(-SH) has a good depressing performance for marmatite and pyrite.The presence of benzene ring in molecule can enhance the depressing performance.The functional group electronegativity,hydrophilic-hydrophobic indexes and frontier orbital of organic depressants were calculated,and the criterion for the depressing effect of organic depressants to sulphide minerals was proposed.

Bioleaching of Zn(Ⅱ) and Pb(Ⅱ) from Nigerian sphalerite and galena ores by mixed culture of acidophilic bacteria

Zn（Ⅱ） and Pb（Ⅱ） from Nigerian sphalerite and galena ores were bioleached by a mixed culture of acidophilic bacteria.The influences of pH and ferric ion on the bioleaching rates of sphalerite and galena were examined.The result shows that pH 2.1 and 2.7 are favourable for the leaching of Zn（Ⅱ） and Pb（Ⅱ） from sphalerite and galena,respectively.It was observed that the use of agarose-simulated media caused cells to excrete exopolymers containing ferric ions which enhanced oxidation.The oxidation equilibrium for sphalerite and galena took 3 and 4 d,respectively.About 38.3% sphalerite and 34.2% galena were leached within 1 d and approximately 92.0% Zn（Ⅱ） and 89.0% Pb（Ⅱ） were recovered in 5 d,respectively.The unleached residual products were examined by X-ray diffraction for sphalerite,revealing the presence of elemental sulphur（S）,zinc sulphate（ZnSO4） and few traces of calcium aluminate（Ca3Al2O6）.The XRD pattern also indicates the presence of elemental sulphur（S）,lead sulphate（PbSO4） and few traces of itoite [Pb（S,Ge）（O,OH）4] and cobalt lead silicate [Pb8Co（Si2O7）3] in the unleached galena ore.