土壤中快速定量分析检测方案(激光剥蚀进样)

NEW WVRESEARCHa division oflfesiWww.new-wave.com Rapid Quantitative Analysis ofSoils by LA-ICP-MS Thereis an increasinglegal requirement for thedetermination of soil pollutant levels， particularly whenformer industrial sites are proposed for residentialdevelopment. The analysis of soils， in some instances，may involve a large number of samples， especially whenland remediation is required before construction canbegin. Soils can not be considered as a single sample“type".Theffield】Cof(conventionalICP-MSsoilsanalysisencompasses a very wide range of matrices， requiring acorrespondingly varied approach to sample dissolution，which can consequently be slow， difficultiandinconvenient. Thecomplete dissolution of samples may requirereagents such as HCI， HCI04 and H2SO4， all of whichyield spectral interferences. Aim of this work Laser ablation sampling for ICP-MS could yield analyticalmethods which offer speed， simplicity and relativefreedom1frominterferences， comparedwith acid-digestion1preparation methods. Ideally，instrumentcalibration standards and analyzed samples should beprepared using a single， simple procedure， allowing theanalysis of a wide range of elements in a wide range oftypical soil matrices using one method of preparation. Soil standards from the International Soil AnalyticalExchange Program (ISE) Wageningen Evaluating Programs for AnalyticalLaboratories， (WEPAL)， IS a co-ordinator ofinterlaboratory exchange programs， including the ISE，which has over 200 members in over 60 countries. Theaim of ISE is to validate analytical procedures for soils，sediments， sludges and composts， through the use ofcertified reference materials and internally generatedsecondary reference materials. Sample Description Sample Description ISE 921 River Clay ISE 961 Clay ISE 950 Sandy Soil ISE 962 Sandy Clay ISE 951 River Clay ISE 985 Forest Soil ISE 952 clay ISE 988 Sandy Soil ISE 958 Sandy Soil ISE 991 Rock Soil Table 1. Soil sample descriptions All of the standards used in this LA-ICPMS applicationare selected from the very wide range of materialsgenerated by the ISE program. The soils， described inTable 1， were selected to represent a broad spectrum ofmatrix types， including clays， sandy soils， rock soils andforest soil. Figure 1. Soil sampling Figure 2. Soil sample pellets used for analysis (small pellet usedfor this study). Instrumentation Laser： New Wave UP213 LA-ICP-MS operating conditions Ablation gas ： He at 0.95 L/min Make-up gas ： Argon at 0.7 L/min Crater diameter ： 100 pm Laser scan speed ： 10 pm/s Laser repetition rate ： 10 Hz Energy density ： 9J/cm2 Sample preparation Dried samples， milled with graphite powder binder in a 1：1ratio， were pressed into pellets of diameter 5 mm in acylindrical die. The graphite powder was doped with fourinternal standards，(Os， Ru， Rh， and W， all present asmetal oxides). Pellets were pressed with an appliedpressure of 2 tons. Ten standards in all were used togenerate calibration graphs for 24 elements. Calibration graphs Examples of calibration graphs are shown in figure 3.These transition elements are typical soil contaminants，often derived frommetalprocessing activities. Allcalibration and analytical data are referenced to one ofseveral internal standards， to correct for sample-to-sample ablation rate variations. Accuracy and precision of LA-ICP-MS data can be limitedby heterogeneity of minerals in some soil types and solaser sampling over a relatively large area is preferred inthis application. Ratio (Y) Figure 3. Calibration graphs for Cr， Cu， Mn， Sc， Vand Zn. USA Element Certified (ppm) Measured (ppm) Accuracy (%) Mg 9014 8805 -2.3 2747 2565 -6.6 18578 18490 -0.5 9.65 9.622 -0.3 3380 3375 -0.1 84.1 81.8 -2.7 245 216.7 -11.6 1034 998.3 -3.5 51.3 51.12 -0.4 126 123 -2.4 897 959.5 7 13 14.51 11.6 38.9 44.23 13.7 97.1 90.23 -7.1 183 229.5 25.4 24.1 26.25 8.9 12.3 11.99 -2.5 921 1045 13.5 30.4 32.54 7 57.9 55.78 -3.7 28.7 26.19 -8.7 1.53 1.58 3.3 251 225 -10.4 8.99 8.766 -2.5 Table 2. Sample analysis-River clay 970 Unknown sample analysis One of the samples， (970， River clay) was analyzed as anunknown using the calibration curves established usingthe other ten reference materials. The results of theanalysis are listed in Table 1. The measured values for 18elements lie within 10%(relative) of the accepted value forthe sample. Conclusions LA-ICP-MS analysis shows excellent potential for fast andaccurate analysis of a wide range of soils. A single samplepreparationprotocol，incorporatingseveralinternalstandard elements， allows calibration using a wide rangeof soil matrix types. Acknowledgments Paul R.D. Mason.Department of Earth Sciences Utrecht University， The Netherlands Johannes T. van Elteren National Institute of Chemistry， Ljubljana， Slovenia JapanTaiwanEuropeChinaNew Wave ResearchNew Wave ResearchNew Wave ResearchNew Wave ResearchNew Wave Researcha division of esia division of esia division of esi.a division of esia division of esi48660 Kato Blvd.Pierwest Square Northwing 2F2FI.，No.58-3，XingShan Road8 Avro Court， Ermine Business ParkRoom 1701~1702， Information Tower，Fremont CA 94538-73391-11-8 Tsukuda， Chuo-kuNeihu Dist..Huntingdon， Cambs，No.1403 Min Sheng Road，United States of AmericaTokyo， 104-0051TaipeiPE29 6XSPudong， Shanghai， ChinaTel：+1510-249-1550JapanTaiwan 114 ROCUnited KingdomP.R.C. 200135Tel：+1 800-566-1743Tel： +81-3-3533-8444Tel：+886-2-8792-7585Tel：+44 1480 456566Tel：+ 86 21 3392 7070Fax： +1 510-249-1551Fax： +81-3-3533-8443Fax：+886-2-8792-7584Fax：+44 1480 456545Fax：+86 21 5237 1289Email： lasers@new-wave.comEmail： newWaveKK@new-wave.comEmail： NewWaveGC@new-wave.comEmail： NewWaveEU@new-wave.comEmail：NewWaveCN@new-wave.com 确定土壤污染物水平的法律要求越来越高，特别是在拟建以前的工业用地作住宅发展时。在某些情况下，土壤分析可能涉及大量样本，特别是在建设开始前需要进行土地修复的情况下。土壤不能被认为是单一的样品“类型”。传统的ICP-MS土壤分析领域含有大量种类的基质，因此需要采用不同的方法进行样品溶解，这个过程是缓慢的、困难的、不方便的。样品的完全溶解可能需要HCl、HClO4、H2SO4等试剂，这些试剂都会产生光谱干扰。