银碲保护－铋试金灰吹－ICP-MS测定地质样品中的贵金属

以毒性小、不易挥发的氧化铋为贵金属捕集剂,硝酸银和亚碲酸钾(mAg/mTe)=1:1为灰吹保护剂,将铋扣在镁砂灰皿中820℃一次灰吹的留铋碲银珠,在预置少量硼砂的瓷坩埚中二次灰吹,得到光滑纯净的贵金属碲银合粒。合粒经王水高压密闭消解后,以Lu、In为内标,ICP-MS测定贵金属,Au、Pt、Pd在0.1~1000 ng/mL,Rh、Ir、Ru在0.1~500 ng/mL线性关系较好,r均大于0.9998。Au、Pt、Pd、Rh、Ir、Ru的方法检出限分别为0.24、0.22、0.21、0.017、0.018、0.019 ng/g,回收率均大于95%。对不同地区、不同类型标准物质测定,结果与认定值的相对标准偏差(RSD)均小于8.57%,相对误差(RE)为-10.00%~15.79%。     

铋试金﹣二次灰吹﹣ICP-AES测定黑色岩中的铂、钯、金

黑色岩中的大量碳、硫、镍影响铋试金的捕集和操作。在铋试金配料中加入硝酸钾、铁粉、硝酸银和亚碲酸钾,可消除碳、硫的影响,且一次灰吹时铋扣能快速脱皮、二次灰吹可得到光滑圆整的贵金属碲银合粒。合粒经硝酸、盐酸溶解,电感耦合等离子体光谱法(ICP-AES)测定,铂、钯、金的回收率均大于97%,方法检出限为Pt 0.020 μg/g、Pd 0.020 μg/g、Au 0.021 μg/g。对标准物质测定结果的相对误差(RE)为-4.31%~3.77%,相对标准偏差(RSD)均小于6.92%。     

四(亚硝基)合钯酸钾的合成、单晶结构及其循环伏安特征

以醋酸钯(PdAc2)与亚硝酸钾(KNO2)为起始原料，水为溶剂，合成四亚硝基钯酸钾(K2[Pd(NO2)4])，产率为96.5%。采用溶剂挥发法培养出其单晶，经X射线单晶衍射分析证实:此晶体由中心对称的[Pd(NO2)4]^2-配阴离子，K⁺阳离子和2分子结晶水组成，为三斜晶系，P-1空间群，晶胞参数为:a=6.4953(5) nm，b=7.0134(5) nm，c=7.1473(5) nm，α=118.784(2)°，β=101.050(2)°，γ=98.085(2)°，Z=1，Pd-N键长为2.014 nm和2.037 nm，∠N-Pd-N为91.70(4)°，且Pd²⁺位于4个N原子组成的平面四边形的中心。采用恒电位仪在室温下测试其循环伏安图，测得其还原峰电位(Ep)为-0.51 V (vs. SCE)。     

湿法分解-组合吸附材料富集—发射光谱法测定区域化探样品中痕量、超痕量Au、Pt、Pd

采用H2O2-HCl分解样品,建立组合吸附材料富集工艺,并详细讨论了组合富集剂的富集条件,通过改进光谱缓冲剂、利用小电极快速曝光技术及研制贵金属光谱分析相板测定系统,提高了仪器信噪比和弱小信号检测能力。方法操作简便、效率高、成本低。检出限(3σ)Au为0.1 ng/g、Pt为0.2 ng/g、Pd为0.1 ng/g,测定国家铂族元素地球化学一级标准物质中的Au、Pt、Pd,结果与标准值相符,12次测定的相对标准偏差(RSD)小于27.1%。方法不仅适合各类矿石中Au、Pt、Pd分析,同样能满足区域地球化学调查样品的分析质量要求,并在不同规模、不同级次、不同采样密度的区域以至全国铂钯地球化学勘查应用中均取得满意成果。     

小试金-碲保护留铅灰吹富集测定矿石中痕量贵金属

采用小铅试金富集,以5 mg碲为灰吹保护剂,通过留铅灰吹法将矿石样品中痕量贵金属(金、铂、钯、铑、铱和钌)定量富集在50 mg左右的铅合粒中。铅合粒先以(1+1)硝酸溶解,再加入盐酸进一步增强溶解能力,基体通过以氯化铅形式沉淀得以分离,采用电感耦合等离子体质谱法(ICP-MS)测定。相对标准偏差(RSD,n=6)为:Au 4.6%、Pt 8.7%、Pd 4.5%、Rh 9.2%、Ir 6.1%、Ru 5.8%。方法用于国家一级标准物质和黑色页岩样品中痕量贵金属的测定,测定值与认定值基本吻合。     

磷-硫-钒-水体系酸性溶液中钒的提取热力学分析

针对含钒酸浸液中钒的有效提取问题，研究了298 K时磷-硫-钒-水溶液酸性体系中钒的提取热力学分析过程。结果表明，在 P(V)-V(V)-H₂O酸性溶液体系中，pH=1~4时VO₂⁺首先转变为磷钒杂多酸阴离子，pH=4~7时磷钒杂多酸阴离子转变为同多酸阴离子；在S(VI)-V(V)-H₂O酸性溶液体系中，pH=0~1时钒主要以VO₂⁺和 VO₂SO₄^-形式存在，pH=2~6时钒逐渐转变为同多酸阴离子；在P(V)-S(VI)-V(V)-H₂O酸性溶液体系中，pH=1~3 时VO₂⁺和 VO₂SO₄^-逐渐转变为磷钒杂多酸阴离子，当pΗ=2时ΣPV₁₄（所有磷钒杂多酸阴离子之和）的摩尔分数最大为88.55%；pH=4~6 时，磷钒杂多酸阴离子消失并逐渐转变为同多酸阴离子，当pΗ=5时ΣV₁₀（所有同多酸阴离子之和）的摩尔分数最大为100.00%。     

王水不溶渣的碱性加压氧化溶解及其钌含量的测定

建立了一种以次氯酸钠作氧化剂,碱性加压氧化法溶解王水不溶渣中钌的方法。以酒精沉淀,盐酸溶解,硫脲分光光度法进行样品中钌含量的测定。方法对王水不溶渣中钌的溶解效果好,操作简单;王水不溶渣加压氧化浸出液共存的主要杂质离子Na⁺、Cl^-、Pb²⁺、Bi²⁺等(不含Os)对吸光度无影响。采用硫脲分光光度法测定样品中13.771 μg/mL钌,RSD (n=6)为1.536%,加标回收率为98.73%~102.76%。     

纳米柱状多孔WO3- x /TiO2 薄膜的电致变色性能

采用反应磁控溅射在掠射角度α=0°和α=80°的条件下制备氧化钨（WO_3-x）薄膜,然后在其表面沉积二氧化钛（TiO₂）。利用X射线衍射仪（XRD）、场发射扫描电镜（FE-SEM）和X射线光电子能谱仪（XPS）对WO_3-x/TiO₂薄膜的晶体结构、表面/断面形貌以及表面化学成分进行表征。在三电极体系1 mol/L LiClO₄/PC溶液中,采用电化学工作站和紫外-可见分光光度计测试了WO_3-x/TiO₂薄膜的电致变色性能。XRD结果表明,WO_3-x/TiO₂薄膜为非晶态结构,与掠射角度无关。当掠射角度为80°时,获得了纳米柱状多孔薄膜。从 W 4f和Ti 2p的XPS谱图确认氧化钨为亚化学计量比的WO_3-x,而氧化钛为满足化学计量比的TiO₂。与致密薄膜相比,纳米柱状多孔薄膜需要较低的驱动电压且具有较快的响应速度。纳米柱状多孔薄膜的电荷容量为83.78 mC,是致密薄膜电荷容量30.83 mC的2倍以上。在±1.2 V驱动电压下,注入和脱出离子扩散速率分别为D_in=5.69×10^-10 cm²/s和D_de= 5.08×10^-10 cm²/s。与纯WO₃薄膜相比,WO_3-x/TiO₂薄膜的电致变色循环稳定性更好。纳米柱状多孔薄膜在可见光范围内具有较大的光调制幅度,因此其光密度变化（ΔOD）大于致密薄膜。     

ICP-MS法测定高纯钯中18个痕量杂质元素

以混合酸(盐酸-硝酸)溶解高纯钯样品,建立了电感耦合等离子体质谱法(ICP-MS)测定高纯钯中18个杂质元素的方法。确定了最佳测定条件为:采用普通模式测定Pt、Rh、Ir、Ru、Au、Ag、Cu、Fe、Zn、Ni、Mn、Mg、Al、Sn和Pb,氨气反应模式测定Si、Fe和Cr(氨气流速分别为0.2、0.3和0.7 mL/min);采用内标校正提高分析的准确性,其中Mg、Al、Zn、Ni、Mn、Cu、Ag、Rh、Ru和Si以Sc为内标,Fe以Y为内标,Sn、Cr和Pb以In为内标,Ir、Au、Bi、Pt以Re为内标。测定各元素的线性相关系数(r)不小于0.9997,方法检出限为0.0061~0.85 ng/mL。对高纯钯样品中18个杂质元素进行测定,相对标准偏差(RSD)为1.38%~6.11%,加标回收率86.2%~118.8%,可满足4N~5N高纯钯产品的测定要求。     

硫代硫酸盐浸出脱铜阳极泥中金、银和钯的研究

密度泛函计算和热力学分析表明,相较于Au(I)和Ag(I)离子,Pd(II)离子更容易与S2O3^2-发生配位反应,3种元素均可被氨性硫代硫酸盐溶液浸出。脱铜阳极泥中高含量的锡和锑对硫代硫酸盐浸出贵金属无明显影响,但铅以PbO形态存在时会覆盖在贵金属表面抑制浸出。硫代硫酸盐对脱铜阳极泥中贵金属的直接浸出率低;阳极泥先经氢氧化钠预处理去除部分铅后浸出率有所提高;经碳酸盐转化-醋酸预处理可去除阳极泥中93.8%的铅,硫代硫酸盐对金、银和钯的浸出率达到88.0%、93.4%和80.7%。X射线衍射(XRD)和X射线光电子能谱(XPS)分析表明,醋酸预处理后阳极泥颗粒表面没有出现PbO钝化层。     

Adsorption properties of Ag（Ⅰ）, Au（Ⅲ）, Pd（Ⅱ） and Pt（Ⅳ） ions on commercial 717 anion-exchange resin

The adsorption properties of the four precious metal ions (Ag(I), Au(II), Pd(III) and Pt(IV)) on the commercial Cl^?-form 717 strongly basic anion-exchange resin were studied in detail. The effects of the contact time, solution acidity, and concentrations of Cl^? and Pb²⁺ ions on the adsorption properties were studied by the batch method. Then, the column method was conducted under the optimized adsorption conditions (pH=3.0). The effects of the sample loading flow rate and the length-to-diameter ratios of the columns were investigated. The precious metal ions adsorbed could not be eluted completely after the saturated adsorption because the precious metal ions were found to be reduced to their metallic states during the adsorption process. So, it is recommended that the commercial Cl^?-form 717 strongly basic anion-exchange resin should be decomposed directly to recovery the precious metals after the saturated adsorption.     

Cloud point extraction and flame atomic absorption spectrometry analysis of palladium, platinum, and gold ions from industrial polluted soil

Cloud point extraction (CPE) with Tergitol TMN-6 was applied for the extraction of trace amounts of palladium (Pd(Ⅱ)),platinum (Pt(Ⅳ)),and gold (Au(Ⅲ)) in the soil of industrial sewage.Ammonium pyrolysine dithiocarbamate (APDC) was adopted as the chelating agent prior to CPE and then was detected by atomic absorption spectrometry (AAS).Different parameters such as the concentration of surfactants,chelating agent and salt,sample pH,equilibration temperature and time,centrifugation time and rates,and the effect of foreign ions were studied.Under optimum conditions,the low limits of detections are 1.4,2.8 and 1.2 ng.ml-1 and the enrichment factors are 21,12,and 24 for Pd(Ⅱ),Pt(Ⅳ),and Au(Ⅲ),respectively.The relative standard deviations vary from 0.6％ to 1.0％ (n=11).All correlation coefficients of the calibration curves are ＞0.9960.The proposed method was successfully applied for the determination of Pd(Ⅱ),Pt(Ⅳ),and Au(Ⅲ) in the real soil of industrial sewage samples.     

铜镍合金氯化渣富集贵金属

针对含贵金属０．１２％的高冰镍磨浮磁选铜合金氯化浸出渣富集贵金属生产流程中的不足,提出了新的工艺流程结构,包括煤油脱除元素硫－熔炼含贵金属高锍－加压酸浸三个步骤,贱金属分离效率（％）：Ｃｕ９９．５、Ｎｉ９９．８、Ｆｅ９４．５、Ｓ９９．６、ＳｉＯ２９８．８;贵金属回收率（％）：Ｐｔ９８．０、Ｐｄ９７．０、Ａｕ９７．０,产出贵金属品位〉３０％,贵贱比〉１的精矿。     

Synthesis of novel composite materials via the deposition of precious metals onto protonated titanate (TiO2) nanotubes

Abstract

Methods for the deposition of precious metals (Au, Pt, Pd and ruthenium hydrated oxide) onto the surface of nanotubular titanates are considered. Viable techniques include preliminary ion exchange of precious metal cations onto the nanotubes followed by chemical, electrochemical or photochemical reduction to the metal. The morphology and size of the metal nanoparticles ranged from spheroidal particles of a few nanometres to larger, rod like particles. The deposits, which were densely loaded onto the surface and were uniformly distributed, had a high surface area and good chemical stability. The size of metal nanoparticles ranged from 1 to 50 nm.     

Adsorption of platinum(IV) onto D301R resin

Pt(IV) was quantitatively adsorbed by D301R resin in the medium of pH = 3.47. The statically saturated adsorption capacity is 410 mg/g. Pt(IV) adsorbed on D301R resin can be eluted by 1.0-2.0 mol/L NaOH. The rate constant is k₂₉₈ = 5.43 × 10⁻⁵S⁻¹. The adsorption of Pt(IV) on D301R resin obeys the Freundlich isotherm. The adsorption parameters of thermodynamics are as follows: enthalpy change ΔH = 4.37 kJ/mol, Gibbs free energy change ΔG = −5.39 kJ/mol, and entropy change ΔS = 32.76 J/(mol·K). The apparent activation energy is E_a = 22.5 kJ/mol. The coordination molar ratio of the functional group of D301R resin to Pt(IV) is 2:1.     

等离子体质谱法测定地质样品中超痕量贵金属和铼

用等离子体质谱法同时测定地质样品中超痕量Au、Pt、Pd、Os、Ir、Ru、Rh和Re。试验了HCl／H2O2封闭溶样法，研究了ZPA4螯合树脂富集8元素的条件，并通过树脂灰化、HCl／H2O2封闭分解制备成试液，供ICP—MS测定。本法的检出限（ng/g）分别为0．21Au、0．12Pt、0．20Pd、0．024Os、0．016Ir、0．028Ru、0．022Rh、0．22Re，方法的相对标准偏差（RSD）为3．1％～14．8％。本法的特点是有效地降低了空白值，提高了仪器的检测能力。     

溶剂萃取分离金川料液中的金钯铂

阐述了石油亚砜（ＰＳＯ）选择性萃取分离Ｐｄ的基本原理，并以此为基础研究了用ＤＢＣ萃Ａｕ、ＰＳＯ萃Ｐｄ及Ｎ２３５萃Ｐｔ，从金川蒸馏Ｏｓ、Ｒｕ之后的脱胶液中萃取分离金、钯、铂的工艺过程     

铂钯精矿湿法分离Bi、Fe富集贵金属工艺

以铜阳极泥分铜液还原所得铂钯精矿为原料,根据其矿物特性选择HCl作为浸出剂湿法脱除Bi、Fe等主要贱金属元素,富集Au、Ag、Pt、Pd等贵金属;通过热力学计算绘制Bi(Ⅲ)、Fe(Ⅲ)在盐酸体系的组分分布图,实验考察了HCl浓度、Cl-浓度、反应温度和时间等因素对Bi、Fe浸出率的影响.结果表明:在HCl浓度为2 m...