Deep Purification of Zinc Ammoniacal Leaching Solution by Cementation with Zinc Dust

Deep purification of zinc ammoniacal leaching solution by cementation using zinc dust was studied.The effects of relative amount of metallic impurities,dosage of zinc dust,purification time,temperature,pH value and total ammonia concentration in the solution on the purification of the solution were investigated.The results indicate that total ammonia concentration in the solution had no effect on the purification,but relative amount of metallic impurities,dosage of zinc dust,purification time,temperature and pH value of the solution were the main factors influencing the purification.Keeping appropriate molar ratio of copper to cadmium or nickel to cadmium was beneficial to the cementation of cadmium.Nevertheless,the presence of cobalt went against the cementation of cadmium and cobalt.All metallic impurities could be decreased to acceptable levels under the optimized conditions of 2 g/L of zinc dust dosage,1 h of purification time,35℃,pH value 9.03 of zinc ammoniacal leaching solution.The deeply purified zinc ammoniacal solution obtained by one-stage purification meets the requirements of zinc electrowinning.     

高磷高铁氧化锰矿硫酸化焙烧与水浸制备锰电解液

为克服传统工艺的缺点,采用氧化锰矿硫酸化焙烧-水浸方法制备电解锰电解液,将氧化锰矿与硫铁矿混合高温焙烧,使四价锰还原成水溶性的二价锰,并在焙烧过程中完成硫酸化过程,生成水溶性MnSO4,而其他杂质元素生成难溶性的氧化物用水直接浸出,避免其进入电解液,不用传统工艺中的酸浸,有利于环保. 通过实验得出在S/Mn摩尔比为3、焙烧温度600℃、焙烧时间270 min的最优工艺条件下,Mn的综合浸出率可达85.6%. 表明本工艺路线是完全可行的.     

Effects of Temperature and Concentration on the Structure and Specific Capacitance of Manganese Oxide Deposited in Manganese Acetate Solution

The deposition of manganese oxide on a carbon substrate in manganese acetate solution by anodic deposition was investigated. The effects of electrolyte concentration (0.05–1 m) and temperature (0–50 °C) on the characteristics of the oxide prepared were explored. The surface morphology of the oxide deposited was examined by scanning electron microscopy (SEM). Oxide whiskers were found on the deposited film surface, and they became coarser and longer when deposited at a high temperature. X-ray photoelectron spectroscopy (XPS) was carried out to examine the composition of the deposit. The results indicated that the oxides deposited at 0 and 25 °C contained trivalent and tetravalent manganese oxide. However, the mixture of bivalent and trivalent oxide was found when the deposition temperature was raised to 50 °C. Moreover, the amount of anhydrous Mn oxide (i.e., Mn–O–Mn) and water content in the deposit gradually decreased with increasing deposition temperature. The concentration of manganese acetate could affect the oxidation state of manganese ions as well as the morphology of the oxide deposited. Cyclic voltammetry (CV) was used to evaluate the electrochemical performance of the oxide deposited. The results showed that the specific capacitance of the manganese oxide increased with decreasing deposition temperature. Moreover, an optimum value of specific capacitance was found for the oxide deposited in 0.5 m manganese acetate solution.     

三明炼钢粉尘的基本物性及酸浸回收锌的实验研究

采用化学分析、XRD、湿式筛分、显微镜观察、SEM-EDS等方法系统研究了三明炼钢粉尘的元素组成、粒度分布、物相、表面形貌及元素分布等基本物性;并进行其酸性浸出条件实验,考察了初始酸浓度、MnO2加入量、温度、浸出时间等因素对矿浆终点pH值、过滤性能及Zn, Fe, SiO2浸出率的影响. 结果表明,在25℃、初始酸浓度26.6 g/L、加MnO2 0.4 g、浸出120 min后,矿浆pH=3.5~3.7,粉尘中Zn的浸出率达98%,而Fe和SiO2浸出率分别为0.22%和9%,且矿浆的过滤性能良好.     

ICP-OES法测定除尘灰中锌、氧化钙、氧化镁含量

除尘灰高温灰化除碳后,转入聚四氟乙烯烧杯,加盐酸、硝酸、氢氟酸溶解,加高氯酸冒烟驱氟,补加盐酸煮沸溶解盐类。通过锌、钙、镁元素的谱线选择、样品消解、称样量、元素线性等方面做了条件试验,实验结果表明在最佳条件下,配制合适含量高纯铁打底的工作曲线,该方法准确度高、周期短,适用于除尘灰中锌、钙、镁元素的快速测定。     

表面活性剂对HCl-FeCl3溶液中锌精矿在浆萃取浸出率的影响

The effects of surfactant on the solvent extraction in leaching sphalerite were investigated. It is found that sodium dodecyl sulfonate is the effective surfactant in improving the zinc recovery from sphalerite in the aqueous FeCla-HCl-tetrachloroethylene system. Through the measurements of surface tension and viscosity of the sphalerite slurry modified with different surfactants, it is concluded that sodium dodecyl sulfonate in the concentration range of 0.05 to 0.2g@L-1 can improve the viscosity of sphalerite slurry in the water, decrease the surface tension of leaching solution, prevent the aggregation of ore particles, and give very high zinc extraction .     

铬铁酸浸液除铁过程的草酸亚铁回收及铁黑颜料制备

对铬铁酸浸液除铁所得草酸亚铁进行氧气氧化-氨浸处理,回收除铁剂草酸盐并用其制备氧化铁黑颜料. 考察了氨水用量、反应温度、液固比、反应时间、氧气流量、反应液pH值及晶化温度等对C2O42-浸出率和氧化铁黑质量的影响. 结果表明,反应液经60℃晶化处理后,在反应温度80℃、氨水与草酸亚铁摩尔比为3、液固比5 mL/g、氧气流量0.1 L/min、pH值6.9~7.4、反应时间3 h的条件下,C2O42-的浸出接近100%,得到的氧化铁黑质量与国产722氧化铁黑产品相当.     

废锌锰干电池中锌及锰的回收利用研究进展

锌锰干电池是干电池中较常用的一种,用完后如不及时处理会对环境造成极大的危害。综述了近年来废旧锌锰干电池中锌及锰的分离回收方法以及再利用,并对未来研究方向进行了展望。     

除草尿素中锌,锰,铁元素的同时测定

介绍使用等离子发射光谱仪同时测定除草尿素中锌、锰、铁含量的方法,建立过程及该方法的优越性。     

由铁矿烧结电除尘灰浸出液制备氯化钾及球形碳酸钙

采用物理化学表征方法研究了包钢烧结电除尘灰的基础性质,结果表明,该烧结电除尘灰的主要成分为Fe,K,Na,Ca的化合物,其中的钾盐可通过水浸分离回收. 浸出液中含有大量可溶性硫酸钙. 为了在浸出过程中抑制硫酸钙的溶解,考察了硫酸钙在KCl,NaCl,K2SO4及其混合盐中的溶解性能. 结果表明,由于KCl和NaCl的盐溶效应,硫酸钙的溶解性能得到提升. 应采用低液固比,提高浸出液中硫酸根离子的相对含量,利用硫酸根离子的同离子效应抑制烧结电除尘灰中硫酸钙的溶解. 以碳酸钠为沉淀剂,考察其对钙离子沉淀效果的影响. 结果表明,碳酸钠具有较好的硫酸钙沉淀效果. 在沉淀钙离子的同时,研究了沉淀剂的浓度、反应温度、搅拌强度对碳酸钙晶体形貌的影响,制备获得了分散良好,粒径小于10 mm的球形碳酸钙副产品,实现了资源综合利用. 最后设计了从烧结电除尘灰提取国标20406-2006一级氯化钾并联产球形碳酸钙副产品的工艺路线,该工艺具有工业应用潜力.     

机械活化对氧化锌矿碱法浸出及其物化性质的影响

研究了不同活化时间、活化方式对云南兰坪低品位氧化锌矿碱法浸出的影响. 结果表明,当浸出液NH4Cl浓度2.0 mol/L、NH3×H2O浓度1 mol/L、温度30℃、浸出液与浸出矿样液固比为10 L/g时,未活化矿样浸出90 min浸出率仅为60.08%,而活化90 min矿样浸出90 min的浸出率为69.36%,为可浸出含锌物相的103.97%;先磨后浸的强化效果优于边磨边浸. 不同活化时间、活化方式不仅造成矿物的形貌、粒度分布不同,而且使矿样在球磨过程中的物相转化存在差异：活化与浸出步骤分离时,球磨过程发生了机械化学反应,矿样中ZnS被氧化成利于浸出的物相,从而比两步骤合并的浸出效果好.     

The Purification of Crude Zinc Oxide Using Scrubbing,Magnetic Separation,and Leaching Processes

Physical separation and hydrometallurgical purification techniques, such as scrubbing, magnetic separation, leaching, and precipitation were used to convert crude zinc oxide into high purity zinc powder. Scrubbing was used to remove the soluble chloride on the crude zinc oxide surface. The solubility of metal oxides contained in the crude zinc oxide was simulated by DIASTAB software to determine the pH ranges for metals precipitation. Leaching under various conditions was conducted to determine optimum operating parameters. From the solubility diagram, the titration ends in the range of pH 5.78~6.1 and high purity (92.2%) zinc powder can be obtained with 82.04% recovery.     

表面活性剂对HCl-FeCl3溶液中锌精矿在浆萃取浸出率的影响

The effects of surfactant on the solvent extraction in leaching sphalerite were investigated. It is found that sodium dodecyl sulfonate is the effective surfactant in improving the zinc recovery from sphalerite in the aqueous FeCl3-HCl-tetrachloroethylene system. Through the measurements of surface tension and viscosity of the sphalerite slurry modified with different surfactants, it is concluded that sodium dodecyl sulfonate in the concentration range of 0.05 to 0.2g L-1 can improve the viscosity of sphalerite slurry in the water, decrease the surface tension of leaching solution, prevent the aggregation of ore particles, and give very high zinc extraction .     

高硅高铁含铜渣氧压酸浸过程

对火法炼铅产高硅高铁含铜渣进行了氧压硫酸浸出过程研究. 结果表明,浸出时间、氧分压、酸量、浸出温度和搅拌速度对Cu的浸出率和浸出液中Fe含量有显著影响,溶液初始含Cu2+量对Cu浸出率影响不明显. 最佳工艺条件为：时间2 h,氧分压0.8 MPa,硫酸浓度46.6 g/L,温度(150±2)℃,搅拌速度600 r/min,复合絮凝剂A用量30~100 g/m3. 在该条件下,Cu浸出率>95%,浸出液中Fe<5 g/L,硫转化率20%~30%,料浆过滤速度约0.8 m3/(m2×h).     

火焰原子吸收法测定液体肥料中的铜锌铁锰

应用火焰原子吸收法测定液体肥料中的铜、锌、铁、锰,并对测定条件、干扰因素进行了综合考察。该方法简便、快速,适用于多元素液肥生产控制分析和样品系统分析     

低品位氧化锌矿氨-碳酸氢铵浸出制备氧化锌工艺的研究

采用氨-碳酸氢铵溶液从低品位氧化锌矿中浸出制备氧化锌。研究结果表明,在氨水浓度7mol/L、碳酸氢铵浓度0.62mol/L、浸出温度50℃、氧化锌矿粉粒度为177μm、液固比5:1、浸出时间3h的条件下,锌一段浸出率为87.2%,经过二段浸出,锌总收率可提高至95.9%;浸出液采用足量锌粉还原除杂后,净化液中铜为0.51mg/L,铬为0.18mg/L,铅可降至0.10mg/L以下;净化液经过蒸氨和焙烧制得的氧化锌含量为99.53%(以氧化锌计)。该方法具有工艺简单、能耗低、浸出率较高、浸出过程对环境较友好等优点。     

中草药白芷中微量元素铁铜锌锰的测定

采用火焰原子吸收分光度法测定白芷中铁锰铜锌的含量,研究了白芷的消化工艺,讨论了原子吸收的测试工作条件,测定结果表明,白芷中铁为310.3μg/g,锰为72.6μg/g,铜为3.9μg/g,锌为47.7μg/g,相对标准偏差为0.49%～4.04%,回收率为99.3%～105%。     

抗坏血酸在锌铁合金镀液中的作用

本文讨论了抗坏血酸的氧化还原反应以及对锌铁合金镀液中Fe^2 和PH值的稳定作用。研究结果表明,抗坏血酸是一种良好的还原剂,虽然在锌铁合金镀液中用量仅为1－2g/l,但作用显著。     

高铁低铝煤矸石酸浸液铝铁分离研究

本文研究以高铁低铝煤矸石酸浸液为对象,根据铝、铁离子水解pH差异,提出了采用先还原Fe3+再进行分离的思路.研究用纯物质模拟酸浸液组成进行铝铁分离,再将结果用于实际溶液,结果表明:对Fe3+已还原的酸浸液,在90℃、pH =4.5时可制备氢氧化铝,过滤,在90℃下滤液通入空气制备水合氧化铁,产品经煅烧,制备的氧化铝产品纯度达到了国标GB/T24487-2009二级品要求,铁红性能指标超过了一级品要求,研究结果对拓展煤矸石资源化应用途径、提高煤矸石综合利用率具有重大意义.     

锌掺杂对针状氧化铁的结构及电化学性能的影响

采用微乳–超临界干燥法制备了Zn2+掺杂针状Zn0.34Fe2.66O4纳米晶。利用红外光谱仪、能谱仪、X射线衍射仪和透射电子显微镜对样品的晶体结构、化学组成、粒径和形貌进行表征。结果表明:产物为形貌规整的针状,长径比明显小于Fe3O4的。通过循环伏安、恒流充放电和交流阻抗等方法研究了Zn0.34Fe2.66O4电极的电化学性能,结果表明:在1mol/L H2SO4溶液中,在0～1.6V(vs饱和甘汞电极)电位范围内,Zn2+掺杂Zn0.34Fe2.66O4材料的电活性和循环稳定性、可逆性优于Fe3O4的。在1A/g电流密度下,单电极比容量达1116F/g,大电流充放电性能良好。