萃取分离电感耦合等离子体原子发射光谱法测定钢中的微量稀土元素

本文采用苯甲酰苯胲(BPHA)-甲基异丁基酮(MIBK)溶剂萃取方法将钢中基体元素Fe,Ti,Mo,V等大量非稀土元素萃入有机相中,稀土元素留于水溶液中.由电感耦合等离子体原子发射光谱(ICP-AES)仪直接测定水溶液中的微量稀土元素La,Ce,Pr,Nd.Sm,Y和Gd,实验结果与推荐值基本相符,方法的回收率为96％～108％,相对标准偏差低于5％.     

鲨鱼软骨质量的聚类分析法

用电感耦合等离子体原子发射光谱法（ＩＣＰ－ＡＥＳ）测定了１８个鲨鱼软骨真品中１３个元素含量，对测定结果进行分析和变量聚类分析，抽提５个特征指标，并以谱系数聚类建立了鉴别鲨鱼软骨真伪的数学模式，用３个假冒产品和一个鲨鱼软骨胶囊对其进行检验，结果表明，用无机元素所建立的数学模式不仅能鉴别鲨鱼软骨的真伪，还能区分鲨鱼软骨的部分及不同部位的混合物。     

Identification of organically associated trace elements in wood and coal by inductively coupled plasma mass spectrometry

1-Methyl-2-pyrrolidinone (NMP) was used to extract samples of wood (forest residue) and coal; the extracts were analysed by inductively coupled plasma mass spectrometry (ICP-MS) using two different sample preparation methods, in order to identify trace elements associated with the organic part of the samples. A sample of fly ash was similarly extracted and analysed in order to assess the behaviour of the mineral matter contained within the wood and coal samples. 32% of the biomass was extracted at the higher temperature and 12% at room temperature while only 12% of the coal was extracted at the higher temperature and 3% at room temperature. Less than 2% of the ash dissolved at the higher temperature. Size exclusion chromatograms of the extracts indicated the presence of significant amounts of large molecular mass materials (>1000 mu) in the biomass and coal extracts but not in the ash extract. Trace element analyses were carried out using ICP-MS on the acid digests prepared by 'wet ashing' and microwave extraction. Sixteen elements (As, Ba, Be, Cd, Co, Cr, Cu, Ga, Mn, Mo, Ni, Pb, Sb, Se, V and Zn) were quantified, in the samples before extraction, in the extracts and in the residues. Concentrations of trace elements in the original biomass sample were lower than in the coal sample while the concentrations in the ash sample were the highest. The major trace elements in the NMP extracts were Ba, Cu, Mn and Zn from the forest residue; Ba, Cu, Mn, Pb and Zn from the coal; Cu and Zn from the ash. These elements are believed to be associated with the organic extracts from the forest residue and coal, and also from the ash. Be and Sb were not quantified in the extracts because they were present at too low concentrations; up to 40% of Mn was extracted from the biomass sample at 202 degrees C, while Se was totally extracted from the ash sample. For the forest residue, approximately 7% (at room temperature) and 45% (at 202 degrees C) of the total trace elements studied were in the extract; for the coal, approximately 8% (at room temperature) and 23% (at 202 degrees C) were in the extract. For the ash, only 1.4% of the trace elements were extracted at 202 degrees C, comprising 25% of Cd but less than 1% of Pb.     

Chloroform extraction of metal ethyl xanthates from hydrochloric acid media

The chloroform extraction of 32 elements (Fe, Co, Ni, Zn, Cd, Ge, Sn, Pb, V, As, Sb, Bi, Cu, Ag, Au, Mn, Re, Ga, In, Tl, Ce, Se, Te, Cr, Mo, U, Pt, Pd, Rh, Ir, Ru and Os) from O.1-10M hydrochloric acid media in the presence of potassium ethyl xanthate has been studied. The oxidation states in which some elements react, and potential analytical separations, are discussed. Pd(II), As(III) and Se(IV) are completely extracted as ethyl xanthate complexes, Te(IV) is almost completely extracted, and Au(III) is largely extracted over the range of acid concentration investigated. Mn(II), Zn, Rh(III), Ir(IV), Ru(III), Os(IV), Cr(III), Cr(VI), Ce(III) and Ce(IV) are not extracted. Ge is partly extracted from 6-10M media as the chloro-complex. Depending on the acid concentration, the remaining elements are all partially extracted as xanthate complexes.     

Methyl isobutyl ketone extraction of iodide complexes from sulphuric acid-potassium iodide media and back-extraction into an aqueous phase

The methyl isobutyl ketone extraction of 15 elements (Cu, Ag, Zn, Cd, In, Tl, Ge, Sn, As, Sb, Bi, Se, Te, Mo and Pd) as iodide complexes from 0.1-5 M sulphuric acid/0.01-0.5M potassium iodide media has been studied. At the optimum potassium iodide concentrations, and a 1:2 v v ratio of organic to aqueous phase, Cu(II), Ag, Cd, In(III), Tl(III), Sb(III), Bi, Te(IV) and palladium(II) are completely extracted in a single step from 1-5M sulphuric acid. All these elements except palladium are also quantitatively extracted from 0.05-0.5M iodide/2M sulphuric acid. Zn, Sn(IV) and As(III) are completely extracted at high acid and iodide concentrations, and at the highest concentrations of acid and iodide investigated, Ge is partly extracted and Mo(VI) is slightly extracted. The extraction of Se(IV) is incomplete because of its reduction to the elemental state by iodide. The back-extraction of the elements has also been investigated and the forms in which they are extracted and potential analytical separations and interferences are discussed.     

Elemental Analysis of Biodiesel by Inductively Coupled Plasma Optical Emission and Flame Atomic Absorption Spectrometries

The extraction of 21 elements from biodiesel using aqueous acid and alkaline solutions was investigated as pretreatment to permit their determination by inductively coupled plasma optical emission spectrometry and flame atomic absorption spectrometry. Al, Ca, Cd, Cu, K, Mg, Mn, Na, V, and Zn were completely extracted from the biodiesel fuel with aqueous acid solution, and Na was completely extracted with alkaline solution. Extraction characteristics varied from element to element; however, 100?±?5% recoveries were obtained with a 30-s extraction procedure. Therefore, although biodiesel is an organic lipophilic material, these elements were determined in aqueous solution. The extracted elements were determined based on traceable Japan calibration service system standards. Accurate analysis of biodiesel was performed using the reported protocol.     

Application of a sequential extraction procedure to study the release of elements from municipal solid waste incineration bottom ash

The release of five elements (Cr, Cu, Mn, Pb and Zn) from a municipal solid waste incineration bottom ash (BA) under different extraction conditions has been investigated by performing the three-step sequential extraction procedure proposed by the Standards, Measurements and Testing Program of the European Union. A fourth step (strong acid attack) has been added in order to calculate the mass balance. The results of this study provide information on the potential mobility of the studied elements. Almost all of the Cr and part of the Mn are extracted with strong acid which indicates low potential mobility in the environment. Most of the Cu is extracted under oxidizing conditions. Pb and Zn are released under acidic condition, indicating the possibility of their mobilization by changes in pH. The reproducibility of the sequential extraction procedure is also discussed.     

A comparison of sequential extraction procedures for fractionation of arsenic,cadmium, lead,and zinc in soil

Twelve soil samples differing in physicochemical properties and total element contents were extracted by three sequential extraction procedures to determine As, Cd, Pb, and Zn bound to individual soil fractions and are defined by individual operational procedures. In the case of arsenic, two additional sequential extraction schemes were designed entirely for fractionation of soil containing arsenic were tested. The results confirmed that determination of element proportions bound to individual soil fractions is strongly dependent on the extracting agent and/or procedure applied within individual extracting schemes. As expected, absolute values of the elements released among the individual extracting procedures are weakly comparable. More reliable results were determined for the more mobile soil elements i.e. cadmium and zinc, in the fractions characterizing the most mobile proportions of investigated elements where significant correlations with basic soil characteristics were observed. In contrast, ambiguous results were observed for As and Pb, for both the individual extraction procedures and the effect of the soil characteristics. Regardless of the studied element, the poorest results were determined for reducible and oxidizable soil fractions. The application of at least two independent procedures or modification of the extraction scheme according to element investigated and/or particular soil characteristics can also be helpful in definition of element pattern in soils in further research.     

Extraction of Rare-Earth Elements in Hydrofluoride Decomposition of Loparite Concentrate

Distribution and existence forms of rare-earth elements in decomposition of the loparite concentrate with ammonium hydrofluoride were studied. It was found that, in the course of the aqueous leaching of the fluorinated concentrate, rare-earth elements fully remain in the insoluble residue as complex salts of general formula NaLnF₄. The process of pyrohydrolysis of the insoluble residue was examined. It was shown that varying the process conditions always results in that a NaLnF4-containing product is obtained. It was found that rare-earth elements can be extracted from the insoluble residue and separated from calcium and thorium, and the conditions for this extraction were determined.     

Flame spectra of sc,y and rare-earth elements

Flame spectra are presented of sandium, yttrium and the rare-earth elements, except cerium and promethium. These elements were extracted with a solution of 2-thenoyltrifluoroacetone (TTA) in 4-methyl-2-pentanone (hexone) and their spectra in the organic medium were subsequently recorded by means of a flame spectrophotometer. The precise wave length and relative spectral intensity of each line and band are tabulated. Included, also, are the 1/2-band widths and the relative spectral interferences of other elements of the group with the emission of measurement of the bands and lines listed. Operating conditions, applicability and limitations of the method in the estimation of some of the rare-earth elements are given     

仲辛基苯氧基乙酸萃取稀土(Ⅲ)的机理

氯化稀土;萃取机理;仲辛基苯氧基乙酸萃取稀土(Ⅲ)的机理     

Mosses as Indicators of Atmospheric Pollution of Trace Metals (Cd, Cu, Pb, Mn and Zn) in the Vicinity of Coal-Fired Brick Kilns in North-Eastern Suburbs of Islamabad, Pakistan

Determination of toxic elements Cd, Pb and other heavy metals has been carried out for Rawalpindi - Islamabad region using the moss monitoring technique. The carpet moss samples (Hypnum Cupressiforme) were collected over an area of 196 km² around lignite/coal-fired brick kilns for regular periods of time during 1997–1999. The elements were extracted into solution with multiacid digestion and then analyzed by atomic absorption spectrometry. The metal contents in moss samples from sites adjacent to coal-fired brick kilns was higher as compared to samples collected from the sites away from that sources. The results obtained by the "BIOMONITORING" technique, for the first time in this area, are presented.     

Liquid-liquid extraction separation and sequential determination of plutonium and americium in environmental samples by alpha-spectrometry

A procedure is described by which plutonium and americium can be determined in environmental samples. The sample is leached with nitric acid and hydrogen peroxide, and the two elements are co-precipitated with ferric hydroxide and calcium oxalate. The calcium oxalate is incinerated at 450 degrees and the ash is dissolved in nitric acid. Plutonium is extracted with tri-n-octylamine solution in xylene from 4M nitric acid and stripped with ammonium iodide/hydrochloric acid. Americium is extracted with thenoyltrifluoroacetone solution in xylene at pH 4 together with rare-earth elements and stripped with 1M nitric acid. Americium and the rare-earth elements thus separated are sorbed on Dowex 1 x 4 resin from 1M nitric acid in 93% methanol, the rare-earth elements are eluted with 0.1M hydrochloric acid/0.5M ammonium thiocyanate/80% methanol and the americium is finally eluted with 1.5M hydrochloric acid in 86% methanol. Plutonium and americium in each fraction are electro-deposited and determined by alpha-spectrometry. Overall average recoveries are 81% for plutonium and 59% for americium.     

Influence of the physical properties and handling of silica gel modified carbon paste electrodes on the phase transfer of solved Cu(II) ions

EDTA, a powerful chelating agent, is used extensively in soil sciences to determine the bioavailability of trace metals and their possible decontamination from polluted soils. Because of its non-selective nature, the co-dissolution of major elements also occurs, in addition to the extraction of trace metal ions.In this work, the reactivity of trace and major elements (Pb, Cu, Cd, Al, Fe, Ca and Mg) with different concentrations of EDTA was studied in eight soil samples (Burgundy, France). The limit between lack and excess of EDTA with respect to total metal extracted, determined after 24 h of reaction for different types of soil varied from 0.002 to 0.05 M, respectively.For calcareous samples the amount of Pb, Cu and Cd extracted by EDTA was reduced to 50% of that extracted in non-calcareous soils.From the kinetic point of view, the extraction behavior of major elements seemed to depend heavily on excess or lack of EDTA and the soil Ca content. For a lack of EDTA, different competitive behaviors were revealed for the major elements (Al, Ca, Fe and Mg) towards the reagent, depending on the soil matrix.According to these experimental results, the mass balance between the reagent and cations in any EDTA-soil media is strongly controlled by major metal extraction. When choosing the reagent concentration needed to extract the trace metals efficiently, all the extractable metal present in the concerned sample must be taken into account.     

Agents and processes design for transuranium elements back extraction in TRPO process

An overview of the work carried out on the development of the stripping of transuranium elements which are extracted by trialkyl phosphine oxide in the actinides-partitioning TRPO process in recent years. Several representative stripping agents and corresponding processes are introduced in three categories of the management of TRU elements: transmutation, alpha waste conditioning and Purex-TRPO integrated process.     

中药化州橘红乙酸乙酯提取物中微量元素的分布及含量

以乙酸乙酯为溶剂萃取分离了中药化州橘红水煎液的有机成分；测定了提取物中元素的分布及含量，分析了不同微量元素在提取物中富集程度的差别。并由此说明了中药微量元素与中药所含的有机成分是有密切关系的。     

Chloroform extraction of ethyl xanthate complexes from sulphuric acid media

The chloroform extraction of 30 elements (Fe, Co, Ni, Zn, Cd, Ge, Sn, V, As, Sb, Bi, Cu, Ag, Au, Mn, Re, Ga, In, Tl, Se, Te, Cr, Mo, U, Pt, Pd, Rh, Ir, Ru and Ce) from 0.1-8M sulphuric acid in the presence of potassium ethyl xanthate has been studied. Pd(II), Bi, As(III), Sb(III), Se(IV) and Te(IV) are completely extracted and Au(III) is largely extracted over the range of acid concentration investigated. Fe(II), Tl(I), Rh(III) and Cr(VI) are only slightly extracted and Se(VI), Te(VI), Ru(III), Cr(III), Mn(II), Zn, Ce(IV), Ir(IV) and Ge(IV) are not extracted at all. Depending on the acid concentration, the remaining elements are all partly extracted. Results are compared with those obtained in an earlier study of the extraction of xanthate complexes from hydrochloric acid media. The processes involved in the formation of some xanthate complexes and potential analytical separations are discussed.     

积雪草中五种微量元素的形态分析

按照传统煎煮法对积雪草中铁、锰、锌、铜和锶5种元素进行提取,用微孔滤膜分离提取液中的可溶态与悬浮态,利用阳离子交换树脂柱、大孔吸附树脂柱和螯合树脂柱对可溶态中的游离态和非游离态、有机态和无机态、稳定态和不稳定态进行分离后,采用火焰原子吸收光谱法(FAAS)对各种形态中的上述5种元素进行测定。结果显示,积雪草中5种元素的提取率为11.88%～22.86%,浸留比为14.04%～31.44%。该法测定各元素的回收率为95.6%～104.3%,相对标准偏差在0.37%～1.14%之间,具有较好的精密度和准确度。     

金银花中6种金属元素的形态分析

对金银花中Mn,Fe,Cu,Zn,Ca和Mg6种金属元素的化学形态进行了分析。用传统的煎煮法把元素提取以后,分别采用0.45μm微孔滤膜、LSA-10大孔吸附树脂柱、正辛醇/水分配体系,以区分元素的可溶态和悬浮态、有机态和无机态、醇溶态和水溶态,最后用火焰原子吸收光谱法(FAAS)对湿法消解以后的各种元素进行测定。结果表明,6种元素的提取率在14.97%～48.54%,悬浮态的颗粒吸附率在4.02%～19.84%,加标回收率在96.58%～103.9%,RSD(n=6)≤2.4%。     

碱熔-标准物质法-电感耦合等离子体发射光谱(ICP-AES)法测定硅酸盐岩中10种主量元素

硅酸盐岩元素的准确测定是其地球化学分析研究的基础,其主量元素含量通常可以采用电感耦合等离子体发射光谱(ICP-AES)法测定,但其测定方法的系统性研究相对缺乏,尤其是样品前处理和基体干扰的有效消除两方面。前处理过程中,考察不同熔剂用量对硅酸盐岩样品的分解能力,发现当熔剂与样品比例达到6:1后,熔珠为纯色透明,经稀硝酸提取后溶液澄清,确定了硅酸盐岩前处理时熔剂与样品的最佳配比。测定过程中,通过考察基体匹配法和标准物质法两种基体干扰消除方法对测定结果的影响,发现当采用与岩性一致或者接近的标准物质绘制校准工作曲线时,基体干扰消除效果更好,更适用于测定硅酸盐岩10种主量元素含量。据此,建立了硅酸盐岩经偏硼酸锂熔融,稀硝酸振荡提取处理,以标准物质法绘制校准工作曲线,采用ICP-AES法同时测定SiO2、Fe2O3、Al2O3、CaO、K2O、MgO、Na2O、TiO2、P2O5、MnO 10种成分含量的方法。对岩石标准物质GBW07107进行分析测定,方法的相对标准偏差(RSD)为0.17%～0.75%,方法检出限为0.001%~0.016%,满足硅酸盐岩样品元素定量分析的要求,而且操作简单快速,环境污染小,适用于大批量样品分析。