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1.
高洪涛  赵砚卿 《分析化学》1999,27(5):566-569
研究了镍铳试金预富集中子活化分析测定岩石样品中的铂族元素。纯化捕集剂氧化镍,大大降低了化学分离全流程铂族元素的空白。取样量为50g时,所需溶剂各元素的空白值为(ng/g):Pt〈0.05、Pd〈0.05、Os〈0.01、Ru〈0.05、Rh〈0.05、Ir=0.002。用平面锗探测器测定Rh使测定下限降低了两个数量级。对几种国标地球化学标准物质的测定结果与推荐值基本符合。  相似文献   

2.
刘继升  邱红莲 《分析化学》1993,21(10):1188-1191
研究了萃取金后用ICP-AES法测定微量Pt、Pd、Rh、Ir、Ag等28个杂质元素的方法。元素间的干扰用等效浓度法校正。杂质元素标准加入回收率为75%~118%;相对标准偏差为4.3%~20%;取样量为2.5g时,测定下限为5×10^5%~2×10^-4%。  相似文献   

3.
段玉然  徐羽梧 《分析化学》1994,22(4):366-369
采用含N,S功能团的螯合树脂YPA4富集铂族元素和金。Au,Pt,Pd,Os的吸附率为98%以上,Ir为92%,Ru为90%,Rh为87%。把树脂灰化,用激光将其灰份气化输入等离子体激发,光谱测定。取样5g时,可测定0.2ng/g的Au,0.6ng/g的Os,Ir,0.06ng/g的Pt,Pd,Rh,Ru。标样分析结果与标准植吻合。  相似文献   

4.
金同顺  贝源 《分析化学》1996,24(3):360-363
研究了一种小型同心氢化物发生配置一个气液分离器后与多道ICP-AES联用,同时测定水和生物样品中砷、铋、锑、硒的方法。检出限为砷0.4μg/L,铋0.5μg/L,锑1.4μg/L,硒0.5μg/L,相对标准偏差为砷2.7%,铋1.5%,锑2.7%,硒1.9%。用本法测定美国和国家标准物质中的氢化元素,结果满意。  相似文献   

5.
研究了用锍扣和锑扣试金富集贵金属,然后用光谱进行测定的方法,拟订了铜镍硫化矿中铂族元素分析的方案,矿石中的铂族元素先用锍扣捕集,酸处理除去贱金属硫化物,再经锑试金把铂族元素富集于毫克量的金属珠中进行光谱测定。一份取样和一次摄谱可以同时分析6个铂族元素。  相似文献   

6.
提出氢化物发生等离子体原子发射光谱(HE-ICP-AES)值接测定中药漏芦中微量As、Sb、Bi的方法。对影响分析信号的主要工作条件进行了选择和优化,对干扰元素及消除方法进行了考察。方法的检出限As、Sb、Bi分别为2.7、3.4、2.8ng/g,精密度(RSD)为2.1%~5.0%,试样加入平均回收率为92.5%~106.5%,本法用于中药漏芦的分析,结果满意。  相似文献   

7.
研究了巯基棉对待测元素Cu、Cd、Pb的预富集性能,并与改进的流动注射法(双流路)相结合,建立了一套新型、高效的在线流动注射-巯基棉分离富集-ICP-AES分析体系,提高了分析方法的频率和灵敏度。Cu、Cd、Pb各元素的检出限分别为0.7μg/L、0.5μg/L和2.9μg/L。10次的相对标准偏差分别为1.71%、2.94%和4.49%。回收率为87.8%~102.4%。  相似文献   

8.
石墨炉原子吸收法直接测定高温合金中硅   总被引:2,自引:0,他引:2  
姚金玉  谢文兵 《分析化学》1995,23(3):284-287
研究了混合基体改进剂,灰北、原子化温度以及共存元素的干扰,采用镧和钙作混合基体改进剂后,硅的灵敏度提高,抗干扰能力增强,可以用石墨炉原子吸收直接测定高温合多中硅。方法特征量为0.2ng,检出限为2.3μg/g,对于含硅量为400μg/g左右的合金样品,相对标准偏差为5%左右,回收率在90%-110%之间。  相似文献   

9.
用锍试金法富集矿石中铂族元素,目前已引起广泛的重视。但是,经锍试金富集后的铂族元素如何测定尚存在许多问题。国内普遍采用锑试金富集,灰吹除去大部分锑,光谱法测定锑珠中的铂族元素,方法仍较繁琐,且大量锑的挥发对操作者身体也不利。本文试验了锍扣经酸处理、除去贱金属硫化物后,酸不溶性铂族元素硫化物富集渣(以下简称富集渣)在高温灼烧滤纸时的行为。发现在少  相似文献   

10.
李春生  柴之芳 《分析化学》1998,26(3):267-270
建立了基于化学逐级溶解、火试金预浓集和电感耦合等离子体质谱分析的地质样品中铂族元素的物相分析新流程。应用逐级溶解,地质样品可被分成即水溶相、可交换相、碳酸盐相、Fe/Ni金属相、硫化物相、氧化物相、硅酸盐相和残渣相8个组分。详细研究了溶解实验中试剂、温度、酸度和时间等实验参数。作为应用的实例,研究了丹麦Stevns Klint K/T界线样品中5个铂族元素的物相分布。  相似文献   

11.
The nickelsulfide fire assay (docimasy) for the enrichment of platinum-group elements (PGEs) has been modified for the use with small samples and combined with instrumental neutron-activation analysis (INAA). This procedure has been applied to the determination of PGEs exhausted from catalytic converters and deposited in soil near the Wiesbadener Kreuz (highway A3, Frankfurt-Köln). Our results show a considerable enhancement of the Pt (up to 330 ng/g), Pd (6.6 ng/g) and Rh (7.5 ng/g) contents close to the highway.  相似文献   

12.
The nickelsulfide fire assay (docimasy) for the enrichment of platinum-group elements (PGEs) has been modified for the use with small samples and combined with instrumental neutron-activation analysis (INAA). This procedure has been applied to the determination of PGEs exhausted from catalytic converters and deposited in soil near the Wiesbadener Kreuz (highway A3, Frankfurt-Köln). Our results show a considerable enhancement of the Pt (up to 330 ng/g), Pd (6.6 ng/g) and Rh (7.5 ng/g) contents close to the highway.  相似文献   

13.
A sequential extraction procedure (three-step), proposed by the Standards, Measurements and Testing Programme (formerly BCR) of the European Union, was applied to street dust and spiked soil samples for the determination of PGEs. Analyses were carried out using inductively coupled plasma-mass spectrometry (ICP-MS). The results indicate that up to 5% from Pt, 70% from Pd and 14% from Rh are in mobile forms in street dust. The results for the soil samples spiked with crushed catalytic converter are significantly lower indicating that PGEs are oxidised more efficiently in natural conditions. Additionally Pt and Pd bound to humic acids were investigated.  相似文献   

14.
An analytical procedure for the reliable determination of Pd, Pt and Rh in plant samples by inductively coupled plasma-mass spectrometry (ICP-MS) was developed. An ultrasonic nebulizer (USN) was used for sample introduction to improve sensitivity. Under various synthetic plant sample matrix compositions, it was established experimentally that moderate amounts (0.2–2%) of dissolved solids decreased the analyte signals significantly. Internal standardisation with In (for Pd and Rh) and Ir (for Pt) proved to be essential for obtaining correct results. Five open digestion approaches, used for converting solid plant samples to aqueous solution, were also tested for the purpose, namely dry-ashing, dry-ashing followed by HF attack, wet digestion with H2O2–HNO3, wet digestion followed by HF attack and aqua regia digestion. Recovery tests in two spiked plant materials showed that only wet digestions must be used. With these ways, all PGEs could be reliably quantified by USN-ICP-MS without applying a separation or preconcentration step with a good precision (below 10% RSD). The aqua regia procedure was applied to the determination of PGEs in various plant matrices collected along a highway. Results showed that mosses were probably the best choice of samples to monitor the bioaccumulation of PGEs in time.  相似文献   

15.
The increasing industrial use of platinum-group elements (PGEs), namely Ir, Pd, Pt and Rh, and related allergies such as rhinitis, conjunctivitis, asthma, urticaria and contact dermatitis, have led to a growing need to monitor selected populations of exposed workers. In this study, the levels of PGEs were measured in indoor airborne particulate matter and in biological samples taken from employees of a plant where car catalytic converters are produced and precious metals are recovered from spent carbon catalysts. The development of an analytical procedure based on quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS) for the analysis of PGEs in airborne particulate matter and on sector field inductively coupled plasma mass spectrometry (SF-ICP-MS) for the analysis of PGEs in blood, serum, urine and hair is described. For airborne particulate matter deposited on filters, the limits of detection (LoDs) were found to be 0.006 ng m−3, 0.020 ng m−3, 0.018 ng m−3 and 0.006 ng m−3 for Ir, Pd, Pt and Rh, respectively. Repeatability of measurements ranged from 1.8 to 8.5%, while recovery was in the range from 92 to 102%. For biological samples LoDs in blood, serum, urine and hair ranged from (in ng l−1) 0.2–0.6 for Ir, 5–10 for Pd, 1–3 for Pt and 2–3 for Rh. For all biological materials, the repeatability varied from 1.1 to 12% for the four elements. Recovery data for the determination of PGEs in biological matrices were found to range from 84.0 to 107.8%. The method was applied to the determination of either total or respirable airborne PGEs collected from five different work areas in the plant. The difference between areas with high and low exposure correlates closely with metal levels in hair, blood and urine. The correlation coefficients between Pt in airborne particulate matter and Pt in biological materials was 0.994, 0.991 and 0.970 for blood, hair and urine, respectively.  相似文献   

16.
A modified NiS fire-assay neutron activation method is developed for the determination of all platinum-group elements (PGEs) in mantle-derived xenoliths. This method is characterized by sub-ppb detection limits, <0.1~0.002 ppb procedural blanks and 7~15% analytical precision for PGEs. Analyses of PGE standard rocks indicate that this modified NiS fire-assay neutron activation method is as reliable as the method previously proposed for a large scale of samples. The capability of the method for the measurement of PGEs in the upper mantle is also illustrated by some exciting results obtained from mantle-derived xenoliths of Eastern China.  相似文献   

17.
Inductively coupled plasma-mass spectrometry coupled with cation exchange matrix separation has been optimised for the direct determination of platinum group element (PGE) and trace element emissions from a diesel engine car. After matrix separation method detection limits of 1.6 ng g(-1) for Pd, 0.4 ng g(-1) for Rh and 4.3 ng g(-1) for Pt were achieved, the method was validated against the certified reference material BCR 723, urban road dust. The test vehicle was fitted with new and aged catalytic converters with and without diesel particulate filters (DPF). Samples were collected after three consecutive New European Driving Cycle (NEDC) of the particulate and "soluble" phases using a home-made sampler optimised for trace element analysis. Emission factors for the PGEs ranged from 0.021 ng km(-1) for Rh to 70.5 ng km(-1) for Pt; when a DPF was fitted, the emission factors for the PGEs actually used in the catalysts dropped by up to 97% (for Pt). Trace element emission factors were found to drop by a maximum of 92% for Ni to a minimum of 18% for Y when a DPF was fitted; a new DPF was also found to cause a reduction of up to 86% in the emission of particulate matter.  相似文献   

18.
The platinum group elements (PGEs), particularly platinum, palladium and rhodium, are nowadays increasingly emitted into the environment from automotive catalytic converters. Thus, a method for the determination of PGEs (especially platinum and rhodium) in dust and plant samples was developed. The developed method was based on microwave-assisted sample digestion and inductively coupled plasma mass spectrometric (ICP-MS) determination. Spectral interferences in ICP-MS determination were corrected using mathematical correction equations based on signal ratio measurement. In addition, platinum and rhodium concentrations in the digested dust samples were also determined after Te coprecipitation without correction of the interferences. The results for platinum and rhodium in reference materials (NIST SRM 2557, recycled monolith autocatalyst and BCR-723, road dust) were in good agreement with the certified values. Preliminary results for the anthropogenic platinum and rhodium emissions in Oulu, northern Finland, based on dust and plant samples, indicated a common traffic-related source of these metals.  相似文献   

19.
Ojeda CB  Rojas FS 《Talanta》2005,67(1):1-19
Anthropogenic emission of platinum group elements (PGEs) from the abrasion of automotive catalytic converters into the environment has significantly increased. Dust emitted from the catalyst is causing pollution problems of these metals in the future. However, the concentration level of these PGEs is still very low in the nature. The choice of which determination method to use depends on the levels of rhodium, the nature of the sample matrix and the availability of the instrument. In recent years, the development of analytical methods for the determination of rhodium has increased. This review reports the developments in UV-vis absorption spectrometry applied to the determination of rhodium.  相似文献   

20.

A novel method for the determination of the platinum group elements (PGEs: Pt, Pd, Rh, Ru) in environmental samples by electrothermal atomic absorption spectrometry (ET-AAS) was developed. Sample preparation involved complete microwave-assisted acid digestion of the matrix with HNO3-HF-HClO3/HClO4mixtures in a high-pressure Teflon bomb. Traces of PGEs were deposited on the inner wall of a graphite tube in a flow-through cell of 1 ml volume. A flow system for this preconcentration was constructed. For the electrodeposition, a three-electrode arrangement was used. The geometry of the cell, flow rate during electrodeposition, deposition potential and electrolyte composition were optimized. After the deposition step, the graphite tube was placed into the graphite furnace and an atomization program applied. Detection limits (LOD, 3σtotal procedure blank, peak area) of 3.6, 0.5, 0.3 and 5.9 ng were obtained for Pt, Pd, Rh and Ru, respectively, reflecting preconcentration factors of 416, 503, 423 and 46, respectively. The detection limits were restricted by variations in the blank. Precision of replicate determination was typically 21% RSD at a concentration 25-fold above the LOD for a 100-mg sample mass. Reasonable agreement was found between results for CW7 road tunnel dust literature and for CRM NIES No. 8 Vehicle Exhaust Particulates. Calibration was achieved via the method of standard additions.  相似文献   

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