印刷电路板酸性蚀刻废液回收工艺中电极反应过程动力学研究

在印刷电路板酸性蚀刻废液中选用Ir系和Ru系电极作阳极,通过稳态动电位扫描和循环伏安扫描,对电极表面发生析氯和电积铜反应过程动力学进行了研究.在0.5 mol/L H2SO4溶液中及20 kA/m2电流密度下,Ir系钛阳极的强化使用寿命为Ru系钛阳极的20倍.Ir系钛阳极的析氯电位比Ru系钛阳极高,两种电极的析氯反应都属于不可逆反应.     

IrO2·Ta2O5涂层钛阳极的研究和应用

在硫酸溶液中使用IrO2@Ta2O5涂层钛阳极电解时,对涂层中的Ir,Ta摩尔比、底层类型进行了研究,发现双底层、Ir与Ta的摩尔比为0.50.5时,涂层钛阳极的快速寿命最长,达889 h.且涂层表面没有裂缝.该电极已广泛用于高温、腐蚀性强的电解行业中.     

镀铂钛电极的研究

讨论了镀液温度、pH值对钛电极镀铂工艺的影响.温度高于360K时,铂的电沉积反应为主要反应.在强酸或强碱性电镀液中,降低析氢反应速度,可避免发生"氢脆现象”.与RuIrTi涂层阳极比较,镀铂钛电极具有较高的析氧电位,其使用寿命也较长.     

IrO2·Ta2O5涂层钛电极电化学性能的研究

与PbAg电极、RuTi涂层电极相比,IrTa涂层钛电极析氧电极电位较低,电催化活性高.测量析氧电极电位时,用汞-硫酸亚汞电极(MSE)作参比电极,可避免溶液不同带来的测量误差.IrTa涂层钛电极适合在较高槽电压下电解运转.     

IrO2·Ta2O5涂层钛电极电化学性能的研究

与PbAg电极、RuTi涂层电极相比,IrTa涂层钛电极析氧电极电位较低,电催化活性高.测量析氧电极电位时,用汞-硫酸亚汞电极(MSE)作参比电极,可避免溶液不同带来的测量误差.IrTa涂层钛电极适合在较高槽电压下电解运转.     

IrO_2·Ta_2O_5涂层钛电极电化学性能的研究

与PbAg电极、RuTi涂层电极相比,IrTa涂层钛电极析氧电极电位较低,电催化活性高.测量析氧 电极电位时,用汞-硫酸亚汞电极(MSE)作参比电极,可避免溶液不同带来的测量误差.IrTa涂层钛电极 适合在较高槽电压下电解运转.     

酸性蚀刻废液再生用钛基电极的电催化与耐腐蚀性能

采用热分解法制备出二氧化铱涂层钛阳极.采用循环伏安曲线、强化腐蚀等方法对酸性蚀刻废液再生用二氧化铱涂层钛阳极的电催化性能、耐腐蚀性能进行研究;应用恒流腐蚀等方法对阴极钛片在盐酸介质中的耐腐蚀性能进行了测试.结果表明,在氧化还原电位为498mV的典型酸性蚀刻废液中,二氧化铱涂层钛阳极表面Cu+的起始氧化电位为0.441V(相对饱和甘汞电极);在HCl质量浓度2mol/L、Cu2+质量浓度20g/L的溶液中,在电流密度0.12A/cm2的条件下,阴极钛片的吸氢腐蚀增量为0.32mg/(cm2.d).     

Pb-Ag阳极涂层制备及其电催化析氧性能

基于提升湿法冶金中Pb-Ag阳极析氧活性、降低析氧过电位的目的, 通过电镀技术在室温条件下制备了一系列不同涂层的Pb-Ag阳极。采用X射线衍射和扫描电镜对涂层的晶体结构和表面形貌进行了表征。并运用线性扫描(LSV)、循环伏安(CV)和交流阻抗(EIS)技术分析比较了不同阳极涂层的电化学性质。研究表明, 加入Mn²⁺、Co³⁺可促进阳极析氧反应的动力学过程, 其中加入Mn²⁺的作用强于Co³⁺; 同时加入Mn²⁺和Co³⁺的电极比单独加入Mn²⁺或Co³⁺离子的电极对析氧反应的促进更明显, 说明具有双复合涂层(PbO₂/MnO₂/Co₃O₄)的铅基阳极最能有效促进氧气的析出, 降低铅基阳极板的析氧电位。     

镀铂钛电极的研究

讨论了镀液温度、ＰＨ值对钛电极镀铂工艺的影响,温度高于３６０Ｋ时,铂的电沉积反应为主要反应,在强酸或强碱性电镀液中,降低析氢反应速度,可避免发生“氢脆现象”,与ＲｕＩｒＴｉ涂层阳极比较,镀铂钛电极具有较高的析氧电位,其使用寿命也较长。     

IrO_2·Ta_2O_5涂层钛阳极的研究和应用

在硫酸溶液中使用IrO3·Ta2O5涂层钛阳极电解时,对涂层中的Ir·Ta摩尔比、底 层类型进行了研究,发现双底层、Ir与Ta的摩尔比为0.5:0.5时,涂层钛阳极的快速寿命 最长,达889 h.且涂层表面没有裂缝.该电极已广泛用于高温、腐蚀性强的电解行业中.     

钛基钛钌铱三元氧化物涂层pH电极的研究

用涂敷技术制备了一种钛基钛钌铱三元氧化物涂层ｐＨ电极。由于在氧化钛涂层中加入了与氧化钛同属金红石晶型的电子导电型半导体化合物氧化钌和氧化铱，因此提高了反应的交换电流密度，有效地克服了用传统的电化学氧化或热氧化法制备的钛基ｐＨ电极的电极斜率低、响应速度慢的缺点，使制得的ｐＨ电极性能优良，可投入实际应用。     

Recovery of dissolved platinum group metals from copper sulphate leach solutions by precipitation

The pregnant leach solution produced in the final leaching stage of base metal refineries (BMRs) operated by platinum producers contains impurities such as selenium and tellurium as well as other precious metals (OPMs, which include Rh, Ru and Ir). The aim of this project was to propose operating conditions for a thio-urea precipitation process that would allow maximum OPM recovery and impurity precipitation from the leach solution with minimal copper and nickel co-precipitation. Experimental results illustrating the effects that operating temperature (80 °C and 160 °C), pressure (atmospheric pressure and seven bar), stirring rate (250 rpm and 500 rpm) and thio-urea quantity (200% and 320% excess) have on the precipitation behaviour are presented.Virtually all of the Rh contained in the solution was precipitated irrespective of the values of the process variables studied. The maximum percentage Ru and Ir precipitation achieved were 87% and 60%, respectively. Complete Se precipitation was observed at all process conditions, while Te precipitation increased as the operating temperature was increased. Increasing the reagent quantity and temperature did, however, also result in increased copper and nickel co-precipitation.Regression models were used to perform numerical analyses to determine suitable operating conditions. Predictions with this numerical approach suggested that precipitation with 200% excess thio-urea at a temperature of 80 °C and a pressure of 7 bar would yield 98% Rh, 75% Ru, and 48% Ir precipitation with less than 5% Cu and Ni co-precipitation; these results could be experimentally validated.     

Investigation of platinum-group minerals (PGM) from Pindos chromitites (Greece) using hydroseparation concentrates

The Pindos ophiolite complex, located in northern Greece, hosts small podiform chromitites characterized by very low platinum group element (PGE) grades. PGE (excluding Os) analyses from four chromitite samples, collected for this study, are below 400 ppb. Consequently, we used the technique of hydroseparation to concentrate PGM from Pindos chromitites. More specifically, we investigated two separate composite samples from Pefki and Milia chromitites.The Pefki concentrate contains 67 PGM that include secondary Ru-bearing minerals, ruarsite (RuAsS), laurite (Ru,Os)S₂, irarsite (Ir,Ru,Rh,Pt)AsS, alloys of Os–Ir–Ru, hollingworthite (Rh,Pt,Pd)AsS, paolovite (Pd₂Sn), braggite (Pd,Pt,Ni)S, sperrylite (PtAs₂) and four unnamed PGM, electrum (Au,Ag) and native silver. The investigation of the Milia concentrate yields fifty one grains of PGM including primary laurite, Os–Ir alloys, erlichmanite, secondary Ru-bearing minerals, irarsite, Ru-alloys, ruarsite and Ru-based metals sulphides. PGM occur as both single and polyphase particles in both concentrates. The bulk of mineralization for grains between 5 and 15 μm is finer-grained in Milia (64.7%) than in Pefki (41.8%). The latter concentrate hosts considerably more altered PGM grains than the former.The hydroseparation process has recovered significantly more, as well as novel, PGM grains than the in situ mineralogical examination of single chromitite samples from the neighboring Korydallos occurrence. Although, most of the PGM occur as free particles and in situ textural information is lost, single grain textural evidence is observed. The mineralogical and grain size differences between the two samples may reflect styles of mineralization and indicate significant remobilization of PGE in Pefki. The latter possibility is suggested by the presence of secondary PGM, which may be related to the different alteration processes that affect the Pefki and Milia chromitites. In summary, this study provides significant information on the particles, grain size and associations of PGM, which are critical with respect to the petrogenesis and mineral processing of these minerals.     

个旧西区拉丁尼克晚期基性火山岩铂族元素地球化学特征

关于个旧锡多金属矿床成因,过去多数人持"燕山期花岗岩岩浆期后气化热液成矿"观点。文章作者认为个旧锡多金属矿床的形成和印支期基性火山沉积成矿作用有很大关系,作者分析了个旧西区拉丁尼克晚期基性火山岩铂族元素的地球化学特征。结果表明,该基性火山岩的铂族元素发生了较强的分异作用,Os、Ir、Ru、Rh亏损,Pd、Pt则发生富集,相对配分模式为Pd-Pt富集型;经球粒陨石及原始地幔标准化的铂族元素配分模式为向左陡倾斜型,具有正的斜率,Pd/Ir高于原始地幔、球粒陨石、原始上地幔等,而与地幔低度熔融形成的N-MORB、大陆拉斑玄武岩等接近,表明该基性火山岩的物质来自上地幔熔融程度偏低的玄武岩浆。     

钛基复合涂层阳极电化学法制备二氧化铈超细粉体

采用钛基钌-铱-铑复合涂层作为阳极, 以硝酸铈和硝酸铵作为电解液, 电化学法制备二氧化铈超细粉体。产品经XRD和TEM分析表明, 粉体属立方晶系, 呈球形, 且粒度小于30 nm;阳极极化曲线表明涂层电极的极化性能优于铂电极, 槽压和能耗均低于铂电极。探讨了溶液浓度、电流密度、pH 值等对电流效率的影响。     

Partial phase diagram of Pd-Ag-Ru-Gd quaternary system

On the basis of the Ag-Pd-Gd, Ag-Ru-Gd and Pd-Ru-Gd ternary systems, the partial phase diagram of Pd-Ag-Ru-Gd(Gd＜25, atom fraction) quaternary system has been studied by means of X-ray diffraction analysis, differential thermal analysis, electron probe microanalysis and optical microscopy.The 700℃ isothermal sections of the Ag-Pd-5Ru-Gd, Ag-Pd-20Ru-Gd and Ag-Pd-50Ru-Gd (Gd≤25,atom fraction) phase diagrams were determined respectively. And the 700℃ isothermal section of the PdAg-Ru-Gd (Gd≤25, atom fraction) quaternary system phase diagram was finally irferred. The section consists of four single-phase regions: solid solution Pd(Ag), (Ru), Pd3Gd and Ag51 Gd14; five two-phase regions: Pd(Ag) + (Ru), Pd(Ag) + Ag51 Gd14 , (Ru) + Ag51 Gd14 , Pd(Ag) + Pd3Gd and (Ru) +Pd3Gd; three three-phase regions: Pd(Ag) + Pd3Gd+ (Ru), Pd(Ag) + Ag51Gd14 + (Ru) and (Ru) +Ag51Gd14 + Pd3Gd; one four-phase region Pd(Ag) + (Ru) + Ag51Gd14 + Pd3Gd. No new quaternary intermetallic phase is found.     

电解冶金中新型涂层钛阳极的研究和应用

电解冶金中，在氯倾物体系电积金属，主要研究涂层钛阳极钝化原因，并对阳极导电性能进行改进，取得节省电能消耗的效果，在硫酸盐体系电积金属，通过添加铱等活性元素，大幅度地提高了涂层钛阳极电催化活性及阳极工作寿命，快速寿命比Ｂ配方的增加２１２倍；在氯化物硫酸盐混合体系电积金属，研究了硫酸根含量对放氯效率的影响。本文研制的涂层钛阳极已在国内一些冶金厂应用。     

小型等离子体铜渣贫化炉的开发研制

将等离子体应用于铜渣贫化领域是一项新的铜渣贫化技术,具有广阔的应用前景。本文以小型等离子体铜渣贫化炉为研究对象,通过COMSOL Multiphysics软件模拟研究了小型等离子体铜渣贫化炉炉腔内部等离子体电子密度的分布情况,为合理选取电源电压、功率及优化炉子电极位置提供依据。利用SolidWorks、3ds Max软件对炉体、升降装置、电极等部分结构进行设计优化。对炉体、电源系统、等离子体发生系统、控制系统和气路系统等进行设计及优化选型设计,研制出一种体积小、保温效果好、操作简洁方便的小型等离子体铜渣贫化炉。该炉子已经应用于某铜冶炼厂,可以将电炉渣含铜降至0.3%以下,取得了很好的贫化效果。     

从二次资源中回收铱的研究进展

铱（Ir）是一种珍贵的铂族金属,在高新技术和军工技术领域中应用十分广泛。我国金属铱的储量极其有限,含铱废料成为重要的铱资源,从这些二次资源中回收Ir的研究备受关注。本文对铱二次资源的来源进行了介绍,并对回收铱的方法如感应熔化、氧化蒸馏、化学沉淀、萃取、吸附等进行了详细的论述。感应熔化法、氧化蒸馏法等方法步骤繁琐、能耗高、回收效率低、污染环境,现今应用较少。化学沉淀法、萃取法、吸附法等方法简便、周期短,但其无法一步完成,需进行二次回收。要实现金属铱二次资源绿色可持续利用,生物法是一个重要的发展方向。