锍镍试金-电感耦合等离子体质谱法测定硫铁矿中铂族元素

锍镍试金常用于富集常规地质样品中的铂族元素(PGEs);而用于富集硫铁矿中的PGEs鲜有报道。硫铁矿中硫和铁的含量较高,采用常规的试金配方不能得到较好的锍扣,影响下一步样品的溶解和过滤。本文对锍镍试金-电感耦合等离子体质谱法测定硫铁矿中PGEs的流程进行改进。针对硫铁矿中硫和铁含量高的特点,在不减少称样量的情况下,调整常规锍镍试金中的试剂配方,获得了理想的锍扣和熔渣,使锍扣富集PGEs的能力达到最佳,且避免了由于反应时间过长而造成PGEs损失。同时利用硫化铁易剥落和粉化的特点,省去了锍扣的机械粉碎工序,简化了流程,避免了碎扣时的机械损失和样品间可能的交叉污染。结果表明,高含量的铁对PGEs的测定无显著影响。加标回收试验显示PGEs全流程回收率大于94%。按10 g取样量计算,方法检出限分别为Ru 0.018 ng/g,Rh 0.017ng/g,Pd 0.18 ng/g,Os 0.019 ng/g,Ir 0.013 ng/g,Pt 0.11 ng/g。实际样品分析和加标回收试验表明,改进后的锍镍试金-电感耦合等离子体质谱测定流程可以满足大多数硫铁矿中PGEs的测定要求。     

锍镍试金富集—等离子质谱法测定地质样品中的金铂钯铑铱钌

建立了锍镍试金富集—电感耦合等离子质谱法测定地质样品中金铂钯铑铱钌的方法。研究了富集时各种实验因素的影响,样品用琉试金富集,盐酸处理锍镍扣,碲共沉淀富集,过滤,沉淀用王水溶解,ICP-M S测定。方法检出限:A u为0.11、P t为0.050、Pd为0.028、R h为0.018、Ir为0.013、R u为0.02,相对标准偏差(n=12),A u为8.25%、P t为4.76%、P t为4.97%、R h为5.63%、Ir为5.38%、R u为6.81%。经国家一级地球化学标准物质验证,铂族元素和金的测定值与标准质相吻合。     

锍镍试金富集-等离子体质谱法测定煌斑岩中铂族元素

试金配料中适量加入铁粉,控制硫化铁在锍扣中的含量在20%~40%,获得的锍扣直接用水浸泡粉化后加盐酸分解,分解结束后趁热过滤,沉淀用1mL王水溶解,定容后上机测定,Cs作内标。改进后的方法空白水平进一步降低,检出限得到显著改善,分析流程简化。采用改进后的锍镍试金富集-等离子体质谱法测定了云南哀牢山金矿带煌斑岩和国家一级标准物质GBW 07288(GPt-1)、GBW 07290(GPt-3)中的铂族元素(PGEs)含量,方法检出限为0.001~0.01ng/g,精密度(RSD,n=5)为7.49%~16.6%。     

ICP-MS法测定化探样品中痕量金铂钯的富集分离方法研究

本方法用HCl和H_2O_2分解试样,以泡沫塑料富集Au、Pt和Pd,在酸性介质中解脱,用电感耦合等离子体质谱法测定化探样品中痕量金铂钯,研究了富集解脱介质及浓度。结果表明,在0.5%NaI+0.5%KBr+20%HCl介质中泡沫塑料对Au、Pt、Pd的吸附率大于95%;在1%硫脲+2%KSCN+2%HCl解脱介质中Au、Pt、Pd的回收率高于90%。方法检出限为Au 0.072 ng/g,Pt 0.17 ng/g,Pd 0.096 ng/g,标准物质的测定值与标准值基本一致,准确度和精密度满足相关规范要求,因此该方法对化探样品中痕量金铂钯的测定有一定实用性。     

锍镍试金富集-电感耦合等离子体质谱法测定黑色页岩中的铂族元素

黑色页岩中碳、硫、镍等元素的含量很高,按照常规的锍镍试金熔剂配方不能形成较好的锍扣,影响铂族元素准确定值。本文通过调整试剂配方、优化操作流程等方式建立了黑色页岩中铂族元素的锍镍试金-电感耦合等离子体质谱(ICP-MS)测定方法。结果表明,加入适量硝酸钾可以将铂族元素回收率提高了大约10%。用盐酸溶解锍扣之后,溶液中仍然存在大量黑色沉淀,不易过滤和溶解,趁热在不断搅拌下加入2～3 mL三氯化铁溶液可以在很大程度上减少沉淀量,降低实验操作的难度和不确定性。方法检出限Ru为0.054 ng/g,Rh为0.040 ng/g,Pd为0.40 ng/g,Ir为0.032 ng/g,Pt为0.27 ng/g,Os为0.026 ng/g。精密度和准确度试验表明,该方法稳定可靠,可用于黑色页岩中铂族元素的准确测定。     

巯基棉富集-分光光度法测定地球化学样品中铂钯的野外快速分析方法研究

对于地球化学样品中铂钯的测定,传统和现代分析方法均是建立在试金或树脂及活性炭富集后用分光光度法或电感耦合等离子体质谱法测定,而在野外满足不了这些条件。本文基于样品的性质及分光光度法的适应性强等特点,开发了一种适合于野外简单条件下快速测定地质样品中铂和钯的分析方法。样品用盐酸-氯酸钾-氯化钠-氟化氢铵常温常压密闭分解,巯基棉分别富集铂和钯,灰化处理后采用三氯甲烷-石油醚(1∶3)为萃取剂,DDO为显色剂萃取比色测定铂、钯的含量。巯基棉对钯的吸附率可达98%;加入氯化亚锡-水合肼(还原剂)使铂的吸附率提高到99%。方法检出限为Pt 0.05μg/g,Pd 0.02μg/g,标准物质的测定值与推荐值基本一致,野外地质样品的测定值与实验室分析结果吻合。     

泡沫塑料富集-电感耦合等离子体质谱法测定土壤中超痕量金铂钯

样品采用王水溶解,二氯化锡还原,泡沫塑料富集,用Re作内标,电感耦合等离子体质谱法同时测定土壤中超痕量金、铂、钯。在盐酸-二氯化锡体系中,盐酸酸度为15%,二氯化锡浓度为45 g/L,吸附时间30 min时吸附效果明显,吸附温度为25℃时吸附率相对稳定。方法检出限Au为0.21 ng/g,Pt为0.18 ng/g,Pd为0.16ng/g,方法加标回收率Au为91.3%~97.8%,Pt为92.0%~96.7%,Pd为96.0%~101.6%。该方法用于测定国家一级标准物质,线性范围宽、重现性好,结果准确可靠,样品处理简便、快速。     

石墨炉原子吸收光谱法测定地质样品中的痕量铂、钯

本文提出了用717阴离子交换树脂富集铂、钯的石墨炉原子吸收光谱分析方法。对富集铂、钯的条件,共存离子的干扰情况以及在GF-2000型石墨炉中测定铂、钯的最佳条件进行了研究。样品用王水分解后,在10％的王水介质中,用717阴离子交换树脂富集铂、钯,以热的硫脲溶液解脱,在拟定的工作条件下,于石墨炉原子吸收光谱仪上进行测定,大量的共存离子不干扰测定。方法简便快速,检出限分别为Pt8.8×10~(-9)g/ml,Pd3.4×10~(-9)g/ml,方法的相对标准偏差分别为Pt7.09％Pd11.48％,适用于地质样品中铂、钯的测定,结果令人满意。     

阴离子树脂-活性炭分离富集等离子体发射光谱法测定富钴锰结壳中的痕量金银铂钯

采用717阴离子树脂活性炭联合交换分离富集技术,电感耦合等离子体发射光谱法同时测定富钴锰结壳中痕量金、银、铂、钯。方法检出限四元素分别为:Au1. 3、Ag0. 4、Pd0. 6、Pt4. 8ng/g。样品加标回收率在89. 0% ~110. 3%,相对标准偏差3. 5% ~7. 8% (n=4)。方法已用于富钴锰结壳中痕量金银铂钯的测定。     

锍镍试金-等离子体质谱法测定地球化学勘探样品中的铂族元素和金Ⅱ．分析流程空白的降低

对锍镍试金富集－等离子体质谱法测定贵金属流程中的试剂空白进行了检查，并对空白主要来源－捕集剂镍的各种纯化方法作了对比，提出了回收试金流程中溶扣后滤液中的镍循环使用。在有效降低空白的基础上，满足了化探样品所要求的0.0x ng/g级检出限，对超痕量贵金属标样分析结果与标准值符合。     

混合吸附剂分离富集-电感耦合等离子体质谱法测定地质样品中铂钯金

贵金属分析应用火试金法分离富集时,试金配料复杂、耗时较长,分析成本相对较高,空白较难控制.本文建立了采用过氧化氢-盐酸湿法分解样品,电感耦合等离子体质谱同时测定地质样品中Pt、Pd、Au的分析方法.在10％的盐酸介质中,以LSC-400巯基树脂和活性炭为混合吸附剂,采用动态吸附方式对样品中的Pt、Pd、Au分离富集,用Lu作内标元素,195 Pt、197 Au、108 Pd为待测同位素消除了非谱线干扰和谱线干扰,三元素的回收率均大于96.4％.方法检出限(3σ):Pt为0.06 ng/g,Pd为0.08 ng/g,Au为0.12 ng/g,优于火试金等其他分离富集方法的检出限.应用于测定国家标准物质,Pt、Pd、Au的测定结果与标准值相符,12次测定的相对标准偏差均小于16.1％,满足区域地球化学调查样品的分析要求.该方法操作简便、成本低廉,提高了分析速度,有效地降低了测试过程的空白值.     

微波消解-电感耦合等离子体质谱法测定铁矿石中15个稀土元素

分析地质样品中稀土元素的含量,现有的方法都受到基体干扰和共存元素干扰,电感耦合等离子体质谱(ICP-MS)已在痕量元素分析中得到广泛应用,通过条件优化可准确测定稀土元素。本文建立了ICP-MS同时测定铁矿石中钇镧铈镨钕钐铕钆铽镝钬铒铥镱镥15个稀土元素的方法,样品用盐酸、硝酸和氢氟酸高温密闭消解,消解完全后转移定容,在线加入¹⁰³Rh、¹¹⁵In、¹⁸⁵Re内标液进行测定,方法回收率为95%~104%,精密度(RSD)≤3.5%。对12个国家24个代表性主产区进口的铁矿石样品进行检测,分析其稀土元素的配分模式特征为右倾型轻稀土富集,现阶段的进口铁矿粉多为多产区复合配矿。本方法较其他传统方法大幅降低能耗,提高了分析效率,初步探讨的稀土元素丰度特征可为研究主产区铁矿石的矿床成因、提高我国烧结球团矿的加工工艺提供依据。     

富钴结壳中贵金属元素的特征

对太平洋CL、CM海山调查时获取9个富钴结壳样品,采用化学处理及ICP-MS法进行分析。对贵金属元素含量分布特征、富集因子、标准化模式以及来源进行探讨和研究。结果表明：海山结壳中贵金属元素Ag、Au、Ru、Rh、Pd、Pt等的平均含量分别为： 1.05×10^-6、2.3×10^-6、15.6×10^-9、22.3×10^-9、2.39×10^-9和432×10^-9。与结核、洋壳及陆地矿石的Pd/（Pt+Pd）、Pt/（Pt+Pd）和Pd/Pt等贵金属元素的比值相比,大洋富钴结壳的 Pd/（Pt+Pd） 比值最低,为0.006;其次是结核,为0.06;洋壳为0.08;陆地矿石的Pd/（Pt+Pd）比值较大,为0.35～0.65。结壳的Pt/（Pt+Pd）比值最高,为0.99;其次是结核,为0.95;洋壳为0.93;陆地矿石的Pt/（Pt+Pd）比值相对较低,为0.33～0.65。统计分析显示了不同区域、不同环境中贵金属元素的特征参数变化,并且说明富钴结壳中富铂、金、钌、铑,而贫钯。贵金属元素标准化显示,海山富钴结壳均存在着Pt、Au正异常和Pd的负异常,其中Au异常幅度与结核的Au异常一致。     

Determination of Platinum‐Group Elements in Geological Samples by Isotope Dilution‐Inductively Coupled Plasma‐Mass Spectrometry Combined with Sulfide Fire Assay Preconcentration

A method was developed for the determination of platinum‐group elements (PGE) in geological samples by isotope dilution‐inductively coupled plasma‐mass spectrometry combined with sulfide fire assay preconcentration. Samples were fused and PGE analytes were concentrated in sulfide buttons. The buttons were dissolved using HCl leaving PGE analytes in insoluble residues, which were digested in HNO₃ and simultaneously processed for the distillation of Os. The remaining solutions were further prepared for the purification of Ru, Rh, Pd, Ir and Pt using a tandem assembly of cation and Ln resin columns. The eluents were directly analysed by membrane desolvation‐ICP‐MS. Ruthenium, Pd, Os, Ir and Pt were determined by isotope dilution, whereas Rh was determined by conventional reference material calibration combined with ¹⁹³Ir as the internal standard element. The method was validated using a series of PGE reference materials, and the measurement data were consistent with the recommended and the literature values. The measurement precision was better than 10% RSD. The procedural blanks were 0.121 ng for Ru, 0.204 for Rh, 0.960 ng for Pd, 0.111 ng for Os, 0.045 ng for Ir and 0.661 ng for Pt, and the limits of detection (3s) were 0.011 ng g^?1 for Ru, 0.008 ng g^?1 for Rh, 0.045 ng g^?1 for Pd, 0.009 ng g^?1 for Os, 0.006 ng g^?1 for Ir and 0.016 ng g^?1 for Pt when a test portion mass of 10 g was used. This indicates that the proposed method can be used for the determination of trace amounts of PGE in geological samples.     

树脂分离富集质谱法测定矿石中痕量铂、钯、金

讨论了王水溶矿、树脂分离富集、在硝酸介质中用质谱法测定铂、钯、金。     

Pt and Pd concentrations and source in urban roadside soils from Xuzhou,China

This investigation represented the preliminary study to characterize Pt and Pd concentrations and enrichment ratios in urban roadside soils. Roadside soil samples were analyzed by ICP-MS. Data from 21 roadside topsoil samples show medians of Pt and Pd concentrations are 2.9 and 2.8 ng g⁻¹, respectively. These values are higher than those of upper crust that average 0.4 and 0.4 ng g⁻¹, respectively. The relatively lower Pt and Pd concentrations are expected due to recent introduction of catalysts to China compared to the prolonged use of catalysts in Europe. Hierarchical clustering analysis indicates that Pt and Pd in Xuzhou urban roadside soils were mainly from the traffic emissions. Computation of enrichment ratios using the upper crust values as background levels suggests that the roadside soils had enrichment medians of 6.4 for Pt (range 2.5–11.75) and of 6.75 for Pd (range 2.75–9.25). Lower Pt/Pd ratios (range 0.35–2.86) in relation to similar studies in other countries were observed due to the different automobile catalytic converters. In general, fine fraction (<250 μm) contains higher Pt and Pd concentrations compared to the coarse fraction (250–500 μm).     

等离子体质谱法直接测定地球化学样品中金铂钯

建立了王水分解地球化学样品报直接用等离子体质谱法测定Au、Pd和Pt的分析方法。方法测定下限为Au4,0ng/g,Pd3.6ng/g,Pt2.4ng/g，方法精密度（RSD，n=12）为Au14.2%,Pd3.6%-5.2%,Pt6.6%-10.8%，三个元素的线性范围都为0.02-300μg/L。采用文中制定的分析方法直接测定了国家一级地球化学标准物质中的Au、Pd、Pt，在测定下限以上的测定结果与标准值吻合。     

First finding of merenskyite (Pd,Pt)Te2 in porphyry Cu-Mo ores in Russia

Contents of Pt and Pd were determined in weakly mineralized rocks, ores, and flotation concentrates of the Aksug porphyry Cu-Mo deposit, northeastern Tuva. In all studied samples they are above the detection limits: Pt = 17–96 ppb and Pd = 9–924 ppb. These elements are unevenly distributed throughout the rocks and ores, with Pd/Pt varying from 0.5 to 37. Study of Pd-rich ores (up to 924 ppb, Pd/Pt = 37) on a JEOL JSM 5600 scanning electron microscope revealed finest (2–5 μm) merenskyite inclusions (25.20% Pd, 1.21% Pt, 72.31% Te) in chalcopyrite. The calculated crystallochemical formula of merenskyite from ores of the Aksug deposit is (Pd_0.862Pt_0.023Cu_0.026Fe_0.025)Te_2.064. The merenskyite is associated with electrum (79.92% Au, 18.96% Ag), monazite, cobaltite, tennantite, and Sr-containing barite (4.6–18.0% Sr). Palladium mineralization occurs in massive chalcopyrite veinlets in zones of intensely propylitized rocks. The Devonian Aksug ore-bearing porphyry complex developed in the field of Early-Middle Cambrian intrusions of gabbro-diorite-plagiogranites associated with basalt-andesite effusions of island-arc complex. This might have led to high PGE contents in the Aksug rocks. The deposit formation proceeded with the participation of ore-bearing Cl-enriched fluids favoring the concentration and transport of PGE in porphyry copper systems.     

A Comprehensive Method for Precise Determination of Re,Os, Ir,Ru, Pt,Pd Concentrations and Os Isotopic Compositions in Geological Samples

A comprehensive method for the precise determination of Re, Os, Ir, Ru, Pt and Pd concentrations as well as Os isotopic compositions in geological samples is presented. Samples were digested by the Carius tube method, and the Os was extracted by conventional CCl₄ method. The Re, Ir, Ru, Pt and Pd were first subgroup separated from the matrix elements into Re‐Ru, Ir‐Pt and Pd by a 2‐ml anion exchange column. Subsequently, the Re‐Ru was further purified by a secondary 0.25 ml anion exchange column or by microdistillation of Ru using CrO₃‐H₂SO₄ as an oxidant followed by a secondary 0.25 ml anion exchange separation of Re. The Pd and Ir‐Pt were further successively purified by an Eichrom‐LN column to completely remove Zr and Hf, respectively. Rhenium, Ir, Ru, Pt and Pd were individually measured by multi‐collector inductively coupled plasma‐mass spectrometry (MC‐ICP‐MS), except for Ru after microdistillation purification was analysed by negative‐thermal ionisation mass spectrometry (N‐TIMS). The analytical results for peridotite reference material WPR‐1 agree well with the previously published data. Finally, several mafic rock reference materials including TDB‐1, WGB‐1, BHVO‐2, BCR‐2, BIR‐1a and DNC‐1a were analysed for Re‐Os isotopes and platinum‐group element concentrations to test their suitability for certification.     

The characteristics of automobile catalyst-derived platinum group elements in road dusts and roadside soils: a case study in the Pearl River Delta region,South China

The emission of platinum group elements (PGE) from automobile catalytic converters has led to enrichment of PGE in road dusts and roadside soils in urban areas that are well above the natural background levels. This paper evaluates the source of contamination of all the PGE and Au in road dusts and roadside soils in the Pearl River Delta region, including three major cities, Shenzhen, Guangzhou and Hong Kong, South China. Samples were digested using Carius tube and analyzed by isotope dilution ICP-MS; Os was separated by distillation and other PGE by Te-coprecipitation. All samples have elevated PGE concentrations above the background values of uncontaminated soils and contain higher Pt, Pd and Rh than other PGE. The maximum values are 181 ng/g Pt, 514 ng/g Pd, 53 ng/g Rh and 1345 ng/g Au. There are clear positive correlations between Pt and Pd, Pt and Rh, and Pd and Rh, indicating that the main emitted of PGE from automobile catalyst are Pt, Pd and Rh. High concentrations of Au were also found in road dust samples from Hong Kong and Shenzhen. Dust samples with higher Os contents have lower ¹⁸⁷Os/¹⁸⁸Os ratios. Samples from Hong Kong show relatively high Pt/Rh ratios. Positive correlations between Pt and Ru, and Pt and Ir were found in Shenzhen and Hong Kong, but only positive correlations between Pt and Ir were found in Guangzhou. These different characteristics reflect different automobile catalytic systems used in Hong Kong and mainland China.