电沉积条件对Ti/Sb-SnO_2/β-PbO_2电极性能的影响

采用电沉积法镀制Ti/Sb-SnO2/β-PbO2电极,研究电沉积时间、镀液温度、pH值、NaF浓度,以及电流密度等因素对电极催化活性和稳定性的影响规律.结果表明,当电沉积时间为1 h,镀液温度为60℃,镀液pH值为1,NaF浓度为0.04 mol.L-1,组合电流密度为600/400 A.m-2(梯度电流密度)时,电极性能最佳,对苯酚降解率达91.4%,强化寿命为23 h.     

电絮凝法处理含聚采油污水的研究

研究采用电絮凝法处理含聚采油污水,优化了电极材料、极板间距、电流密度、pH和电解时间等对污水COD和聚合物去除率有影响的因素.研究确定的电絮凝法处理含聚采油污水的最优工艺条件为:电流密度为7mA/cm2,电解时间40min,极板间距2 cm,pH 9.1.于最优条件下处理后COD和聚合物的去除率分别为68.5%和49.7%.     

废弃电路板铜锡多金属粉隔膜电积回收锡实验研究

采用基于隔膜电积湿法冶金新工艺从废弃电路板铜锡多金属粉中高效提取金属锡,研究并优化了铜锡多金属粉浸出及隔膜电积提锡工艺.浸出实验结果表明,在温度为40℃,初始Sn~(4+)质量浓度50 g/L,HCl浓度4 mol/L,液固比为5∶1,循环浸出三次的条件下,锡浸出率约为96%,最终浸出液中Sn~(2+)质量浓度68.58 g/L.锡隔膜电积实验表明,在Sn~(2+)质量浓度40~100 g/L,HCl浓度3 mol/L,温度35℃,电流密度200 A/m2的条件下,阴极电流效率97.51%,能耗低于1 200 k Wh/t.在此优化条件下进行隔膜电积8 h,得到平整、致密且纯度99.9%的阴极锡板.     

电催化氧化降解活性红紫X-2R染料废水的研究

采用复极性三维三相电极反应装置对活性红紫X-2R染料进行了电催化氧化降解试验,分析了外加电压、主电极极间距、电流密度、初始pH值、曝气量等因素对降解效果的影响,确定了最佳工艺条件:外加电压30 V,电流密度28 mA/cm2,主电极极间距5 cm,初始pH值6,曝气量3 L/min,初始质量浓度为400 mg/L的染料废水经50 min电催化氧化后,脱色率与COD的去除率分别达99.1%和93.5%.     

电催化氧化降解活性红紫X-2R染料废水的研究

采用复极性三维三相电极反应装置对活性红紫X-2R染料进行了电催化氧化降解试验,分析了外加电压、主电极极间距、电流密度、初始pH值、曝气量等因素对降解效果的影响,确定了最佳工艺条件：外加电压30 V,电流密度28 mA/cm2,主电极极间距5 cm,初始pH值6,曝气量3 L/min,初始质量浓度为400 mg/L的染料废水经50 min电催化氧化后,脱色率与COD的去除率分别达99.1%和93.5%.     

电絮凝-微滤法去除水中腐殖酸的实验研究

采用电絮凝-微滤组合工艺技术去除水中过量的腐殖酸,探讨了电流密度、极板间距和pH值对去除腐殖酸效果的影响.结果表明,电絮凝-微滤组合技术去除腐殖酸效果明显,电絮凝反应器的最佳工作参数为电流密度=3.17 A.m-2,极板间距=1.0 cm,pH值在酸性范围内.     

工艺参数对Ni-SiC纳米复合镀层沉积速率的影响

用电沉积的方法在铜表面制备了Ni-SiC纳米复合镀层,研究了不同的工艺参数,包括阴极电流密度、镀液中纳米SiC悬浮量、镀液pH值、镀液温度和搅拌速度对复合镀层的沉积速率的影响。结果表明:在实验电流范围内,镀层的沉积速率随着阴极电流密度的增大呈线性上升的趋势;随着镀液中纳米颗粒悬浮量、镀液pH值及搅拌速度的增大而增大,当达到一定值时,又开始下降;随着镀液温度升高,逐步降低。最佳参数为:不烧焦镀层前提下的最大电流,纳米颗粒体积质量为5 g/L,pH值3.5～4.0,温度30℃,搅拌速度为中高速。     

Ti/SnO2-Sb2O3/Fe-PbO2电极电催化氧化氨氮的研究

用热分解和电沉积联合的方法制备了Ti/SnO2-Sb2O3/Fe-PbO2电极,并采用SEM、ICP和阳极极化曲线对所制备的电极进行了表征。以氨氮为目标污染物,考察了该电极的电催化氧化性能。研究结果表明:Ti/SnO2+Sb2O3/Fe-PbO2电极晶粒细小、致密,具有较高的析氧电位。采用该电极电催化氧化氨氮的最佳工艺条件为:电流密度为20 mA.cm-2、板间距为1 cm、温度为30℃、溶液pH值为5和Cl-浓度为1 100 mg.L-1,经电催化降解后,氨氮的去除率可达100%。     

用废旧电路板酸浸-电沉积法回收金属铜

为了既保障环保又达到最佳铜回收效果的目的,以废旧电路板经过初步破碎分离,得到铜金属富集产品为研究对象,采用硫酸-双氧水浸出结合电沉积工艺回收物料中的铜。考察了铜浸出率与硫酸质量浓度、双氧水用量、浸出时间、液固比之间的关系,进行最佳金属浸出条件实验。结果表明：硫酸物质的量浓度为3.5 mol/L、浸出时间3 h、双氧水用量为20 mL、液固比10∶1条件下,铜金属浸出率最高可达到97.58%。电沉积尾液循环用以浸出铜,铜离子循环质量浓度不低于18 g/L,平均电流效率高于97.60%。在沉积温度40℃,阴极材料为T2紫铜,电流密度小于800 A/m2时,电流效率可以保持在97%以上。实验中铜回收率达到了97.58%。     

Ti/α-PbO2/β-PbO2电极电催化氧化处理苯酚废水

采用电催化氧化法,以自制Ti/α-PbO2/β-PbO2电极为阳极,在室温条件下对苯酚模拟废水进行降解研究,探讨电流密度、电极间距、pH值及苯酚初始质量浓度对苯酚降解效率的影响规律.结果表明,在电流密度为600 A·m-2,电极间距为1.0 cm,pH值为3,苯酚初始质量浓度为100 mg·L-1的条件下,苯酚降解效率达92%以上.紫外光谱等实验结果表明,苯酚在氧化降解过程中会产生苯醌等中间产物,苯酚及其中间产物最终被矿化为CO2和H2O.     

含砷低品位硫化铜矿生物堆浸工业试验

福建紫金山含砷低品位硫化铜矿年产300tCu和1000tCu生物堆浸工业试验结果表明:铜浸出率随着矿石粒度的减小而提高,矿石粒度为-30mm,浸出周期为270d,铜的浸出率达到80.58%;铜萃取率和电积电流效率随着浸出液pH值的降低和电积液中铁的质量浓度的增加而降低,当浸出液pH值下降到1.19时,铜萃取率下降到了50%;通过增加堆高、定期中和萃余液、增加负载有机相洗涤和活性炭+沙滤+气浮塔脱除电积原液中有机物等工艺改进后,降低了萃取剂、煤油和电能的消耗量,提高了铜的浸出速率,浸出周期为200d,铜浸出率为81.31%,铜萃取--电积的耗电量为2679.98kW.h.t-1,高纯阴极铜生产成本1.05万元.t-1.     

强碱溶液中电沉积金属锌粉技术

碱浸-电解法制备金属锌粉技术具有流程简单、环境友好、适应性强等特点.本文通过能斯特方程计算了强碱性溶液中锌沉积的理论分解电动势,并考察碱浓度、锌浓度、极距、电流密度、搅拌等参数对金属锌粉质量和电流密度的影响,得到最佳的电解条件为：碱浓度4 mol/L,锌浓度30 g/L,极距3 cm,电流密度1000 A/m2,不搅拌.在最佳条件下电解得到的金属锌粉,全锌含量为97.38%,金属锌含量为96.79%,基本达到《锌粉的质量技术要求（ GB/T6890-2000）》的一级标准.     

Deep cleaning of a metallurgical zinc leaching residue and recovery of valuable metals

Huge quantities of zinc leaching residues (ZLRs) generated from zinc production are dumped continuously around the world and pose a potential environmental threat because of their considerable amounts of entrained heavy metals (mainly lead). Most ZLRs have not been properly treated and the valuable metals in them have not yet been effectively recovered. Herein, the deep cleaning of a ZLR and recovery of valuable metals via a hydrometallurgical route were investigated. The cleaning process consists of two essential stages:acid leaching followed by calcium chloride leaching. The optimum conditions for extracting zinc, copper, and indium by acid leaching were a sulfuric acid concentration of 200 g·L-1, a liquid/solid ratio of 4:1 (mL/g), a leaching time of 2 h, and a temperature of 90℃. For lead and silver extractions, the optimum conditions were a calcium chloride concentration of 400 g·L-1, a pH value of 1.0, a leaching time of 1 h, and a temperature of 30℃. After calcium chloride leaching, silver and lead were extracted out and the lead was finally recovered as electrolytic lead by electrowinning. The anglesite phase, which poses the greatest potential environmental hazard, was removed from the ZLR after deep cleaning, thus reducing the cost of environmental management of ZLRs. The treatment of chlorine and spent electrolyte generated in the process was discussed.     

Extracting copper from copper oxide ore by a zwitterionic reagent and dissolution kinetics

Sulfamic acid (SA), which possesses a zwitterionic structure, was applied as a leaching reagent for the first time for extracting copper from copper oxide ore. The effects of reaction time, temperature, particle size, reagent concentration, and stirring speed on this leaching were studied. The dissolution kinetics of malachite was illustrated with a three-dimensional diffusion model. A novel leaching effect of SA on malachite was eventually demonstrated. The leaching rate increased with decreasing particle size and increasing concentration, reaction temperature and stirring speed. The activation energy for SA leaching malachite was 33.23 kJ/mol. Furthermore, the effectiveness of SA as a new reagent for extracting copper from copper oxide ore was confirmed by experiment. This approach may provide a solution suitable for subsequent electrowinning. In addition, results reported herein may provide basic data that enable the leaching of other carbonate minerals of copper, zinc, cobalt and so on in an SA system.     

镍电解阳极液直接电解净化除铜研究

本文探讨了镍电解阳极液直接进行电解净化除铜处理过程。镍电解阳极液中的ＣＵ２＋离子优先于Ｎｉ２＋离子在镍电极和铜电极上放电还原，其电极过程具有溶液扩散传质步骤控制的动力学规律。在阴极电位不低于－０．５００Ｖ（ｖｓ．ＳＣＥ．）和溶液搅拌条件下，采用多孔镍作阴极在常温下就能使镍电解阳极液的ＣＵ２＋离子浓度降至０．００２ｇ／Ｌ以下，达到深度净化除铜要求。加强溶液搅拌和增大电极面积有利于加快电解净化除铜速度，电解净化除钢产物为９９％以上的金属铜粉。     

Comparison of effective parameters for copper powder production via electrorefining and electrowinning cells and improvement using DOE methods

The influences of cupric ion concentration (5-35 g/L),current density (500-2000 A/m2),circulation rate of the electrolyte solution (15-120 mL/min),and temperature (25-60℃) on the physical and chemical properties of copper powders obtained in electrolysis cells were investigated.Two industrial processes,electrorefining (ER) cells with a synthetic electrolyte and electrowinning (EW) cells with an original solution of coppermineral leaching,were utilized to produce copper powders.Finally,the statistical full factorial method of design of experiments (DOE) was employed to investigate the interaction or the main effects of processes.The results show that increasing the copper concentration and temperature can increase the grain size,apparent density,and electrical energy consumption.On the other hand,increasing the current density and circulation rate of the electrolyte can decrease them.This production process is optimized via DOE to control the interactive and main effects to produce copper powders with favorable properties.     

电化学法处理含铜废水的实验研究

以不锈钢作阴极,用电化学方法,比较了用石墨和钛基二氧化铅作阳极对废水中铜的去除效果,发现后者效果更佳.实验证明:pH值越低、温度越高、电流密度越大,铜去除率越高.数据还显示:无缓冲剂时,反应液的pH值随反应进程下降;加入磷酸缓冲液,溶液酸化受阻,不利于铜的去除.利用无缓冲剂时溶液随反应进程酸化的特点,在温度为30℃和电...     

Comparison of effective parameters for copper powder production <Emphasis Type="Italic">via</Emphasis> electrorefining and electrowinning cells and improvement using DOE methods

The influences of cupric ion concentration (5–35 g/L), current density (500–2000 A/m²), circulation rate of the electrolyte solution (15–120 mL/min), and temperature (25–60°C) on the physical and chemical properties of copper powders obtained in electrolysis cells were investigated. Two industrial processes, electrorefining (ER) cells with a synthetic electrolyte and electrowinning (EW) cells with an original solution of copper mineral leaching, were utilized to produce copper powders. Finally, the statistical full factorial method of design of experiments (DOE) was employed to investigate the interaction or the main effects of processes. The results show that increasing the copper concentration and temperature can increase the grain size, apparent density, and electrical energy consumption. On the other hand, increasing the current density and circulation rate of the electrolyte can decrease them. This production process is optimized via DOE to control the interactive and main effects to produce copper powders with favorable properties.     

含酚液中苯酚的电催化降解研究

在电激励下,电极表面活性点生成的.OH能氧化水溶液中的有机物。本文研究了钛基二氧化铅电极做工作电极催化降解水中苯酚时,支持电解质溶度、温度、电流密度、pH值等因素对酚降解效率的影响。实验得知,在支持电解质CNa2SO4=0.05 mol.L-1、20℃2、0 mA.cm-2、pH=3条件下,电解100 mL 0.005mol.L-1苯酚溶液,120 min内降解了78.62%。紫外光谱分析了200 min内的电解试样,得知苯酚电解过程先生成中间物而后变成CO2和H2O,且降解率为94.35%。     

Enrichment of copper and recycling of cyanide from copper–cyanide waste by solvent extraction

The enrichment of copper from copper–cyanide wastewater by solvent extraction was investigated using a quaternary ammonium salt as an extractant. The influences of important parameters, e.g., organic-phase components, aqueous pH values, temperature, inorganic anion impurities, CN/Cu molar ratio, and stripping reagents, were examined systematically, and the optimal conditions were determined. The results indicated that copper was effectively concentrated from low-concentration solutions using Aliquat 336 and that the extraction efficiency increased linearly with increasing temperature. The aqueous pH value and concentrations of inorganic anion impurities only weakly affected the extraction process when varied in appropriate ranges. The CN/Cu molar ratio affected the extraction efficiency by changing the distribution of copper–cyanide complexes. The difference in gold leaching efficiency between using raffinate and fresh water was negligible.