Electrolytic Removal of Cadmium, Lead and Copper from Wastewater

The respective compounds of copper, cadmium and lead, owing to their strong toxic potential, as a result of industrial effluent, have left a trail of contamination in humans and the environment. This paper aimed to study the electrode position on the removal of aqueous solutions of cadmium, lead and copper, using an electrolytic cell with a metallic screen cathode of carbon steel and platinum anode. Removal efficiencies were obtained by analysis of the solutions before and after treatment, using the methodology of cathodic-stripping voltammetry with a mercury drop electrode to quantify the concentrations of Cd2+, Pb22+ and Cu2+. Removal efficiencies were obtained of 94.07% for cadmium, 94.71% for lead and 96.19% for copper, demonstrating that electrolytic removal is an effective technique for the removal of these metals from simulated industrial wastewater.

Lead isotopic systematics for native copper-chalcocite mineralization in basaltic lavas of the Emeishan large igneous province, SW China: Implications for the source of copper

The Emeishan continental flood basalt, which is widespread in Yunnan, Guizhou and Sichuan provinces of Southwest China, is the volcanic product of a Permian mantle plume, and native copper-chalcocite mineralization associated with the basalt is very common in the border area of Yunnan and Guizhou provinces. The mineralization occurred in the tuff intercalation and terrestrial sedimentary rock intercalation which were formed during the main period of basalt eruption. The orebodies are controlled by the stratigraphic position and faults. Metal ore minerals in the ores are mainly native copper, chalcocite and tenorite, with small amounts of chalcopyrite, bomite, pyrite and malachite, and sometimes with large amounts of bitumen, carbon and plant debris. Several decades of ore deposits are distributed in the neighboring areas of the two provinces, while most of them are small-scale deposits or only ore occurrences. By comparing the lead isotopic composition of the ores with that of the wall-rocks, cover and basement rocks of various periods, the source of copper in this type of ore deposits was studied in this paper. The results showed that: (1) The Pb isotopic composition of the ores from ten deposits is absolutely different from that of siliceous-argillaceus rocks of the Upper Permian Xuanwei Formation, limestones of the Lower Permian Series and Carboniferous, Cambrian sandstone-shale and recta-sedimentary rock and dolomite from the upper part of the Meso-Proterozoic Kunyang Group. This indicates that ore lead was derived neither from the cover rock nor from the basement rocks; (2) Although the Neo-Proterozoic Siman dolomite and silicalite, and dolomite in the lower part of the Kunyang Group are similar in Pb isotopic composition to the ores, lead and copper contents in these rocks are very low and they have not made great contributions to copper mineralization; (3) The ores have the same Pb isotopic composition as the basalt, the latter being enriched in copper. These facts indicate that lead and copper were derived from the basalt. According to the regional geological data and the geological-geochemical characteristics of the ore deposits, it is suggested that ore-forming materials were leached out from the basalt. The thickness and buried depth of the basalt and regional tectonic dynamics can affect the formation of large-scale copper deposits. Therefore, exploration for this type of ore deposits should be conducted in the areas from western Yunnan to western Sichuan, where there are developed basalts of great thickness, with extensive tectonic movement and magmatic activity.

Adsorption of Lead(II),Copper(II) on tourmaline from Altai mine in China's Sinkiang

Tourmaline from Altai mine in China＇s Sinkiang was used to remove lead （II）, copper （II） from aqueous solution. The results demonstrate that tourmaline contains Na（Mg,V）3AI6（BO3）3Si6Ols （OH）4, NaFe3AI6（BO3）3Si6Ols（OH）4. The data show that Tourmaline from Altai mine in China＇s Sinkiang can be used natural adsorbent for lead （II）, copper （II）.It is observed that the adsorption data fitted to the Langmuir isotherm. Furthermore, both Pb （II） and Cu （II） absorbed by tourmaline and tourmaline were characterized by X-ray diffraction, Laser Raman Spectrum, Fourier transform infrared spectroscopy, X-ray energy dispersive spectrometer, Transmission electron microscopy and Zeta potential.

INTERFACIAL TENSIONS OF SOLID COPPER/LIQUID LEAD AND SOLID COPPER/LIQUID BISMUTH

The solid-liquid interfacial tensions of Cu(solid)-Pb(liquid)andCu(solid)-Bi(liquid)binary systems have been determined by the dihedral angle method.The results show that at 850℃ the interfacial tensions are 368±55mN/m for Cu-Pb sys-tem and 336±35mN/m for Cu-Bi systa,respectively,the error ranges of which aremore narrow than those found in some papers published abroad.In addition,there is nodetective segregation of other solute atoms or compounds in the vicinity of the tip of cop-per grain boundary where dihedral angles formed.

Determination of Copper and Lead Contents in Soil of the Yellow River Wetland in Shaanxi Province by Flame Atomic Absorption Spectrometry

[Objectives] The contents of copper and lead in the soil of the Yellow River Wetland were determined by flame atomic absorption spectrometry, which provides a theoretical basis for the treatment of soil pollution. [Methods] The soil was digested with a concentrated nitric acid-hydrofluoric acid-perchloric acid system, and the contents of heavy metals such as copper and lead in the Yellow River Wetland of Shaanxi Province were determined by flame atomic absorption spectrometry. [Results] The correlation coefficients reached 0.999 5 in the range of 0.00-1.00 mg/L, indicating good linearity. [Conclusions] The method is simple in operation, good in reproducibility, high in sensitivity to most elements, and can be widely used.

METALLOGENIC ANALYSIS OF THE DEXING COPPER-GOLD-LEAD-ZINC POLYMETALLIC DEPOSITS, JIANGXI PROVINCE, CHINA

The paper discusses the tectonic setting of the fortnation of the Dexing giant copper-gold-lead-zinc deposit and its geological features and demonstrates in detail the polygenetic compound mechanism of its formation.

The study on the rough surface of KFC copper strip applied to lead frame

In the paper, the rough surface of KFC copper strip applied to lead frame was studied and analyzed. The method of energy spectrum analysis, SEM and metallographic analysis are adopted to study and analyze. To compare the component of the rough surface of KFC copper strip with one of the normal copper strip, the component abnormity is not found. But to observe its microstructure of the rough surface, there are thinner and regular dimpling in the surface before the polishing, and bigger crystal grains are found after the polishing. The coarse structure vanished when the sample is heated higher than 700℃. It is shown that current annealing technique is not reasonable and should be improved and optimized.

Electroless Plating Lead and Lead-Tin on Copper Using an Eco-Friendly Plating Bath

Copper serpentines used in gas heaters are currently coated with lead-tin alloy using hot-dip technology where copper is immersed in molten lead (98%)-Tin at about 400°C. The major drawback of this technique is the pollution resulted from lead vapors which cause much harm to the labors in the unit. The present work investigates an eco-friendly plating technique to replace the currently used technology. Electroless plating of copper samples with lead or Lead (98%)-Tin alloy is carried out from a plating bath contained lead salt, tin salt, reducing agent and stabilizing agent. The parameters affecting the coating quality such as the plating time, temperature and bath composition were optimized. The chemical analysis and coating morphology of the formed coatings are examined by XRD, SEM and EDS to reach the best bath composition as well as the best conditions to coat copper with lead or lead-tin electrolessly. The electrochemical properties of copper and copper coated samples are also examined using electrochemical impedance spectroscopy.

四川彭州大宝山铜矿矿石与三星堆青铜器关联性研究

四川广汉三星堆遗址出土了大量青铜器,目前关于三星堆青铜器铜料来源的研究尚无定论,通过对大宝山铜矿遗留矿洞进行实际调查,并在不同采矿点采集矿石以及冶炼弃渣样品进行铅同位素测定以及Cu、Pb、Zn等主要金属元素,Au、Ag、Se、As、Sb等亲铜元素和Ni、Co等亲铁元素的含量测定。采用铅同位素比值法和微量元素示踪法,与前人对三星堆青铜器化学成分的研究结果进行比对,综合分析大宝山铜矿与三星堆青铜器铜料来源的关联性,结果揭示:①大宝山铜矿石为普通铅,用铅同位素比值法对三星堆这类含特殊铅青铜器的铜料进行溯源研究不能准确得到其铜矿石来源。②微量元素含量特征表明三星堆大部分青铜器的微量元素组合特征与大宝山铜矿的微量元素特征接近。③通过微量元素的进一步因子分析和聚类分析,表明三星堆部分青铜器的微量元素组合特征与大宝山铜矿大部分样品相似,该部分青铜器铜料很可能来自大宝山铜矿。

纳米比亚哈达普铜铅金属矿普查区遥感地质解译与应用

研究区位于非洲纳米比亚中南部区域,具有寻找铜铅金属矿的良好潜力。为配合地质勘查工作,查明区内铜铅矿资源成矿地质条件,选取SPOT-6、ETM+、ASTER等3种卫星遥感数据,建立遥感解译标志并开展详细地质解译及蚀变信息提取工作,同时在分析研究区矿产分布规律的基础上,分别从岩石地层、地质构造及遥感蚀变信息等方面总结归纳遥感找矿标志,并进行找矿预测。结果表明,区内各地质体影像特征差异明显,遥感解译成效好,解译出主要含矿层位地质界线,包括新解译岩体23处。对典型区域进行野外验证,经调查均为花岗岩体,解译成果与地质工作吻合度高,圈定4处有利找矿预测区。其中II号预测区,解译结果反映该区隐伏的含矿岩系可能受后期构造作用影响而抬升,有望寻找热液型和同火山岩有关的矿床。研究成果为该区矿产勘查提供遥感支撑,也可为周边类似区域遥感地质工作提供参考。

铜和陶瓷低温钎焊接头研究

通过在陶瓷表面镀铜将陶瓷表面金属化,然后在温度227℃、压强0.04MPa、保温2min条件下,使用Sn99Ag0.3Cu0.7焊锡膏将镀铜陶瓷与铜进行钎焊,并通过光学显微镜、扫描电镜对钎焊接头进行观察分析。试验结果表明:铜合金和陶瓷在低温下钎焊能够形成金属化合物层,实现有效焊接,钎焊接头强度可达13.2MPa。

高频燃烧红外吸收法测定铜铅锌多金属矿中的碳、硫

铜铅锌多金属矿中的碳、硫元素对矿产开采、钢铁冶炼及环境保护等方面有着重要的影响,对碳、硫的准确、快速定量检测至关重要,但未见有对铜铅锌多金属矿中的碳、硫同时测定的研究。将铜铅锌多金属矿中碳、硫含量科学分为C1、C2、S1、S2四段,并分别对样品称样量、助熔剂加入比例及种类等因素进行探究,建立了高频燃烧红外吸收法测定铜铅锌多金属矿中的碳、硫的方法,并通过标准物质验证了方法的准确度、精密度与再现性。结果表明,C1、C2、S1、S2称样量分别为0.200 0、0.100 0、0.100 0、0.100 0 g,助熔剂组合方式为Fe+W=(0.6000+0.6000)、(0.6000+0.6000)、(0.9000+0.6000)、(0.6000+0.600 0) g为最佳实验条件。C1、C2、S1、S2曲线的相关系数分别为0.999 4、0.995 9、0.999 9、0.998 9,测定结果的相对标准偏差(RSD,n=11)分别为1.3%、1.5%、1.3%、1.3%,使用3种不同型号的红外碳硫仪进行对比实验,相对标准偏差(RSD,n=11)为0.56%~6.5%。结果均显示,方法准确、可靠,满足铜铅锌多金属矿中碳、硫的同时、准确快速定量检测的要求。

引线框架用高性能铜合金板带材及制备工艺

电子信息产业的飞速发展,对铜及铜合金产品性能提出了更高的要求,其中集成电路封装用引线框架材料代表了铜合金板带材发展的较高水平。本文对近年来引线框架用高性能铜合金板带材及制备工艺进行了综述,介绍了国内外高性能铜合金板带材料的成分和制备加工技术及发展过程,并对其未来发展趋势进行了展望,提出未来高性能铜板带材性能将朝着抗拉强度为700 MPa、导电率为70%IACS的目标发展,其制备工艺将向着智能化、绿色化、高效化等方向发展。

青海某铜铅锌多金属矿选矿工艺研究

针对青海某铜铅锌多金属矿,进行了不同类型捕收剂对铜铅锌浮选分离影响的试验,重点考察了新型捕收剂4037B、P5100C、QBSC的选别效果。结果表明:P5100C和QBSC更有利于铜、铅分离,在最佳条件下,采用铜快速浮选—铜铅混选—铜铅再磨分离—锌浮选流程,获得铜品位35.56%、铜回收率75.23%的铜精矿;铅品位45.02%、铅回收率71.92%的铅精矿;锌品位41.49%、锌回收率72.58%的锌精矿;含铜20.14%、含铅8.90%、含锌28.38%,铜回收率11.93%、铅回收率6.77%、锌回收率11.81%的混合精矿。全流程铜总回收率97.94%,铅总回收率96.62%,锌总回收率92.64%。

Lead isotopic study of Shang Dynasty bronzes (13-11 B.C.)and their ore sources

The Shang Dynasty civilization in China is based on the development of the bronze techniques. A large amount of Shang Dynasty bronzes, excavated from Jiangxi, Hubei and Henan Provinces, have become a focus of world attention. However,the Sha-ng Dynasty center was located at Zhenzhou and Allyang city areas, Henan Province, where no large copper ores have been found so far. Therefore, where did the huge ore material for casting the bronzes come from? It is an unsettled question paid attention by the archaeologists and scicntists. 35 Shang Dynasty bronzes and 21 copper and lead ore materials aged in the Shang-Zhou Dynasty, the Spring-Autumn Period and the modern time, have been measured by the use of mass spectrometry.Based upon lead isotopic ratios, the ore material for casting the bronzes with the middle isotopic ratios of 207Pb/206Pb ranged in 0.8～0.9 could come from the ancient copper mine of Tongling, Jiangxi Province and Tong Lushan, Hubei Province and that with the high isotopic ratios (＞0.9) could be from the northern part of the Shang Empire, called "Gongfang" in the historical records, e.g. today’s Hebei and LiaoningProvinces. The others with the low isotopic ratios (＜0.8) might originate from poly-metalic deposits, with the high isotopic ratios of 238U/204 Pb in the ore flux or in the magma.

某低品位铅锌铜多金属硫化矿富集与分离试验研究

云南某低品位铅锌铜多金属硫化矿铅品位0.61%、锌品位3.28%、铜品位0.25%,伴生Au、Ag品位分别为0.09、18.04 g/t。矿石嵌布粒度较细,共生关系复杂。为高效开发利用该低品位矿石,进行了系统的浮选试验。结果表明:矿石采用铜铅混合浮选—铜铅分离—锌浮选工艺处理,获得了铜品位21.97%、铜回收率80.85%、金品位1.60 g/t、银品位189.00 g/t、铅品位1.80%的铜精矿,铅品位76.22%、铅回收率88.72%、金品位0.75 g/t、银品位1433.00 g/t、铜品位1.87%的铅精矿,锌品位52.18%、锌回收率93.03%的锌精矿,主要有价成分铅、锌、铜的分离与富集效果较好,金、银一定程度富集在铜精矿、铅精矿中;铜精矿锌含量偏高与黄铜矿、闪锌矿间的嵌布关系异常密切有关;原矿Au、Ag品位低,且在矿石中分散程度高是造成金银综合回收指标偏低的原因。

江西德兴银山铜铅锌多金属矿床稳定同位素地球化学研究

针对银山铜铅锌多金属矿床进行氢、氧、硫、铅同位素研究,以判定其成矿物质的来源。研究结果表明:δD值为-78.9‰~-28.5‰,平均值为-56.5‰;δ18OV-SMOW值为12.10‰~18.70‰,平均值为16.06‰;δ^(18)O_(H_(2)O)值为0.18‰~11.26‰,平均值为8.24‰;反映了成矿流体是岩浆水和大气降水的混合。δ34S值为-1.04‰~2.71‰,平均值为1.35‰,与矿区赋矿地层张村岩组的硫同位素明显不同,暗示了成矿物质不是直接来自地层,但呈现出明显的幔源硫(-3‰~3‰)特征,与矿区火山-次火山活动有紧密联系。铅同位素206Pb/204Pb=17.890 0~18.319 0,207Pb/204Pb=15.528 0~15.602 5,208Pb/204Pb=38.025 2~38.445 0,表明铅来源为壳幔混源,矿石与岩浆岩具有亲缘性。

高温烟气热解废轮胎过程中痕量金属Cu、Pb的迁移特性分析

废轮胎(WT)作为一种常见固废,不合理的处置会对环境造成较大污染。本文采用燃煤高温烟气对WT进行热解,重点研究了热解过程中重金属Cu和Pb的释放特性,以及不同金属氧化物(CaO、MgO、Al_(2)O_(3)、Fe_(2)O_(3))对两种重金属的控制效果,此外还研究了添加聚氯乙烯(PVC)对两种重金属迁移释放的影响。结果表明,当热解时间为10min时,两种元素已经基本释放完全。高温促进了Cu的富集,而低温反而促进了Cu的释放。对Pb元素而言,随着温度的升高,其释放量不断增加,展现出明显的线性规律。当WT添加金属氧化物热解时,MgO促进了Cu的富集,而Al_(2)O_(3)促进了Pb的富集。当WT添加PVC热解时,低温促进了Cu的富集,而高温促进了Cu的释放。但不论温度的高低,PVC的添加使得Pb几乎完全释放。此时,添加Fe_(2)O_(3)对两种重金属的释放均起到了抑制作用。

铜熔炼渣的火法回收工艺与铅锌锑富集规律

铜精矿火法冶金后产生的熔炼渣经浮选回收铜后,尾渣含Pb、Zn和Sb,仍具有一定回收经济价值。浮选法对铜熔炼渣中Pb、Zn和Sb的回收率低,而火法熔炼通过高温和碳热还原可以有效分离这些元素。对直接还原熔炼、造锍还原熔炼和氧化-还原熔炼3种典型的火法回收工艺进行了对比中试试验。结果表明:火法回收工艺可达到理想的铜回收率,但不同工艺对Pb、Zn和Sb的回收效果不同;直接还原熔炼提高了Pb的回收率;造锍还原熔炼提高了Zn的回收率;熔炼法需消耗大量还原剂和能源,经济性需慎重考虑。火法熔炼适合作为铜回收的备用工艺进行研究。

铜铅混合精矿硫酸预氧化-浮选分离参数优化试验研究

方铅矿与黄铜矿的分离一直是选矿领域的难点,使用硫酸预氧化可选择性抑制方铅矿表面可浮性,使得两种矿物可浮性产生差异,实现浮选分离。针对铜铅混合精矿硫酸预氧化-浮选分离工艺进行了系统的参数优化。首先,利用单因素试验,分析了预氧化硫酸浓度、温度、时间等关键因素对铜铅混合精矿浮选分离效果的影响;其次,利用正交试验分析,建立了预氧化过程中各影响因素与浮选指标之间的数学模型;通过模型求解,得到最佳预氧化条件为硫酸浓度5 mol/L、时间40 min、温度100℃。最后在上述条件下进行了混合精矿预氧化-浮选闭路试验,获得了铜精矿Cu品位18.03%,Cu回收率94.52%;铅精矿Pb品位47.12%,Pb回收率为91.29%的良好指标,铜铅分离效果显著,对铜铅硫化混合精矿的浮选高效分离提供了一定的借鉴。