DFT research on activation of sphalerite

Activation of sphalerite ZnS, (Zn, Fe)S, (Zn, Cu)S were carried out using the density functional theory (DFT) method. The electronic structures and related properties of three kind of zinc sulfide compounds were investigated. In addition, the relation between electronic structure and flotation behavior was discussed. The results show that, ZnS has a broader band gap than (Zn,Cu)S and (Zn,Fe)S do, and it has low electrochemistry activity to react with flotation collectors to render the surface hydrophobic. When the Zn atom in ZnS is replaced by Cu atom,the band gap will be reduced, and the top valence band will be occupied by Cu 3d orbit, thus it is beneficial to the interaction between mineral surface and collector.     

Flotation performances of polymorphic pyrrhotite

The floatability of different crystalline structures of pyrrhotite (monoclinic and hexagonal) was studied. It is shown that the floatability of monoclinic and hexagonal has obvious difference, and that the flotation recovery of monoclinic pyrrhotite is larger than that of hexagonal pyrrhotite using different collectors. When butyl dithiophosphate is used as the collector, the recovery is larger than that by sodium butyl xanthate and sodium diethyl dithiocarbamate. At the pH values ranging from 6 to 9, monoclinic pyrrhotite can be floated well, and the flotation recovery is higher than 90%. Monoclinic and hexagonal pyrrhotites are more easily activated by Cu²⁺ in acidic conditions than in alkaline conditions. But Cu²⁺ cannot activate hexagonal pyrrhotite using sodium diethyldithiocarbamate as the collector. By the measurement of contact angle, it is indicated that monoclinic and hexagonal pyrrhotites float well and are easily activated by Cu²⁺ when dithiophosphate is used as the collector. Using sodium diethyl dithiocarbamate as a collector, the relationship between potential and pH range for pyrrhotite flotation is established. At pH 5, the optimal potential range for flotation of monoclinic pyrrhotite is about 125–580 mV (vs SHE), with the maximum flotation occurring at about 350 mV (vs SHE); the optimal potential range for flotation of hexagonal pyrrhotite is 200–580 mV (vs SHE), with the maximum flotation occurring at about 300 mV (vs SHE).     

丁基黄原酸甲酸乙酯的合成及对黄铜矿浮选研究

考察了不同条件对丁基黄药合成丁基黄原酸甲酸乙酯(BXEF)的影响。研究结果表明,合成BXEF反应的最佳工艺参数为：反应温度25℃,反应时间200 min,n(丁基黄药)：n(氯甲酸乙酯)=1．04：1。在此条件下,BXEF的产率可以达到94．5%。对江西永平铜矿硫化物矿石的浮选试验结果表明,与丁基黄药相比,BXEF对硫化铜矿有更高的浮选回收率,而且铜精矿中铜的品位更高。对丁基黄药和BXEF的量子化学计算结果表明,BXEF比丁基黄药有更低的能量,稳定性更强。     

含锰溶液中Fe、Pb杂质的脱除工艺研究

对浮选方铅矿精矿和软锰矿两矿法共同浸出含锰溶液中Fe、Pb杂质的净化工艺条件进行了研究。得出了在pH为4时，采用针铁矿法除铁，其除铁效果已达到要求。在温度为4513、pH为4、硫化剂／方铅矿为1／20％时，采用硫化法除重金属，浸出液中的Fe、Pb杂质含量达到1mg／L，已经满足制备工艺要求。     

Corrosive electrochemistry of j amesonite by cyclic voltammetry

The corrosive electrochemistry of jamesonite was studied by cyclic voltammetry. Every peak in voltammograms was identified through thermodynamic calculation. The results show an irreversible electrode process by the strong adsorption of oxidation elemental sulfur on jamesonite. A deficient-metal and sulfur-rich compound is formed under the potential of 80 mV at pH 6.86. The passive action by elemental sulfur occurs from 80 to 470 mVand S2O3^2-, SO4^2- are produced at potential over 470 mV. The anodic peak producing SOz- is inhibited due to the deposition of PbSO4 at higher potential in Na2SO4 solution. The corrosive action of jamesonite becomes strong and the redox characterization similar to PbS, FeS and Sb2S3 appears at pH 9.18.     

浮选理论,工艺及设备的新进展

浮选理论、工艺和设备在近二年有了长足的进展，国内外许多学术刊物和会议都有关于浮选方面的研究报道，浮选作为矿物加工方面的一项重要技术已有许多新的进展。1浮选理论和工艺浮选理论与工艺，相对较多的集中在硫化矿、氧化矿和细粒矿三个方向的研究。浮选电化学仍旧是硫化矿浮选研究的重要方向，包括无捕收剂浮选和电控浮选的研究。硫化矿表面的氧化是浮起分离的决定因素，徐秉权等人研究了凡口铅锌矿磨矿过程中，矿石与介质的电化学反应，磨矿电位的调控可以减少磨矿介质和能量的损耗[1]。kelebe研究发现[2]，加拿大某镍铜硫化矿浮选时…     

废旧锂离子电池资源现状及回收利用

废旧锂离子电池的无害化处理及回收利用已经成为各个科研院所研究的重点及热点内容。本文系统介绍了废旧锂离子电池的资源现状与目前回收利用的各种不同的工艺路线,并且详细分析了各种工艺路线的优缺点,以期为废旧锂离子电池的回收与利用找到新的思路与方法。最终认为“化学?物理联合法”为当前废旧锂离子电池无害化处置及回收利用的较为理想的方法。      

黄药体系磁贡铁矿表面双黄药的稳定性及其浮选研究

本文研究了黄药体系中磁黄铁矿电极表面吸附的双黄药的稳定性。采用怀电位阶跃法确定了丁基黄药离子在磁蓼铁矿表面的扩散系数Ｄ为２．２５×１０＾－６ｃｍ＾２／ｓ；采用循环电位扫描法确定丁基双黄芭博学 原为黄药离子的阴极反应为一不可逆电化学反应，结合恒电流阶跃法建立了双黄药在磁黄铁矿电极表面还原角吸的电化学还原动力学方程。     

Kinetics of electrochemical process of galena electrode in diethyldithiocarbamate solution

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

黄铜矿与斑铜矿在酸性细菌培养基中的电化学溶解对比(英文)

采用电化学测试和X射线光电子能谱(XPS)测试分析黄铜矿与斑铜矿在酸性细菌培养基中的电化学溶解过程。斑铜矿直接氧化反应比还原反应更容易发生,但黄铜矿既难被氧化,又难被还原。斑铜矿具有更高的氧化速率,从而比黄铜矿更容易被溶解。铜蓝(CuS)是黄铜矿与斑铜矿溶解过程的中间产物。因此,斑铜矿的溶解途径主要为直接氧化过程,中间产物铜蓝(CuS)可能限制其进一步溶解。黄铜矿的溶解途径包含了还原-氧化过程,其中,黄铜矿首先被还原为与斑铜矿类似的中间产物,再进一步被氧化,并产生铜蓝(CuS),而黄铜矿的最初还原过程是其溶解过程的主要限制步骤。