Geochemical analysis of marine sediments using fused glass disc by X-ray fluorescence spectrometry

A method was developed for content determination of Na, Mg, A1, Si, P,S, C1, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Nb, Zr, Y, Sr, Rb, Ba, La and Ce etc. covering 26 major, minor, and trace elements in marine sediment samples using fused glass disc by X-ray Fluorescence spectrometry. Calibration was made using marine sediment certified reference materials and the synthetic standard samples prepared by mixing several marine sediments with stream sediment and carbonate standard samples in different proportions. The matrix effect was corrected using theoretical alpha coefficients, experience coefficients and the scattered radiation as the internal standard （for the trace elements）. The accuracy of the method was evaluated by analysis of certified reference materials GBW07314, GBW07334 and GSMS6. The results are in good agreement with the certified values of the standards with RSD less than 2.60%, except for Y, Cr, Ga, Ce, La, Nb, Rb, and V with RSD less than 9.0% （n=12）.

X-ray fluorescence spectrometry determination of open-hearth furnace slag by pressed powder briquetting

A rapid analysis method of determining content of eight compounds of open-hearth furnace slag was developed using X-ray fluorescence spectrometry and pressed powder briquettes. Matrix effect was corrected using theoretical alpha coefficient. Grains-size effect was eliminated by optimized sample preparation technique parameters. Mineral effect was corrected with standard curve of specially made standard samples. The analysis results of TiO2, TFe, SiO2, MgO, Al2O3, CaO, MnO and P2O5 in slag samples showed that both precision and accuracy are comparable with that of chemical method.

Determination of Content of Eight Elements in Metal Coating Smeared on Waste Plastics by X-ray Fluorescence Spectrometry

X-ray fluorescence spectrometry was used to detect the content of eight elements in metal coating smeared on waste plastics,and effects of sample cups,elements in plastic substrate,and interaction of elements in metal coating on detection results were analyzed. The results show that the RSD of the method used to detect element content in the metal coating smeared on the waste plastics ranged from 0.008% to 0.044%; the determination range of the eight elements was 0.002%-52.0%,and their detection limit ranged from 0.0002% to 0.0008%. The determination results of X-ray fluorescence spectrometry were consistent with that of ICP-AES. The method can provide technical support for the determination of damage and pollution caused by metal coating smeared on waste plastics.

Quantitative Analysis of FeMo Alloys by X-Ray Fluorescence Spectrometry

A quantitative analysis method of molybdenum in FeMo alloys by X-ray spectrometry using borate fusion technique was compared with that with pressed pellet. The complete pre-oxidation of FeMo alloys for the preparation of homogeneous fused discs was achieved by employing an automated fusion machine equipped with specially designed O2-blowing nozzles, which used lithium tetra-borate as flux with the addition of lithium nitrate (LiNO3) as oxidizer. The calibration curves of Mo and Fe were used in the quantitative analysis of standard materials and unknown plant samples with satisfactory accuracy and precision, utilizing the corrections of the matrix effects and line overlap. It was confirmed that the newly proposed method of preparing fused glass discs of FeMo alloys can replace the conventional wet chemical analyses requiring the labor intensive and time consuming procedure.

Elemental and proximate analysis of coal by x-ray fluorescence assisted laser-induced breakdown spectroscopy

Although laser-induced breakdown spectroscopy(LIBS),as a fast on-line analysis technology,has great potential and competitiveness in the analysis of chemical composition and proximate analysis results of coal in thermal power plants,the measurement repeatability of LIBS needs to be further improved due to the difficulty in controlling the stability of the generated plasmas at present.In this paper,we propose a novel x-ray fluorescence(XRF) assisted LIBS method for high repeatability analysis of coal quality,which not only inherits the ability of LIBS to directly analyze organic elements such as C and H in coal,but also uses XRF to make up for the lack of stability of LIBS in determining other inorganic ash-forming elements.With the combination of elemental lines in LIBS and XRF spectra,the principal component analysis and the partial least squares are used to establish the prediction model and perform multi-elemental and proximate analysis of coal.Quantitative analysis results show that the relative standard deviation(RSD) of C is 0.15%,the RSDs of other elements are less than 4%,and the standard deviations of calorific value,ash content,sulfur content and volatile matter are 0.11 MJ kg,0.17%,0.79% and 0.41%respectively,indicating that the method has good repeatability in determination of coal quality.This work is helpful to accelerate the development of LIBS in the field of rapid measurement of coal entering the power plant and on-line monitoring of coal entering the furnace.

L-shell x-ray fluorescence relative intensities for elements with 62≤Z≤83 at 18 keV and 23 keV by synchrotron radiation

The relative intensities of L-subshell x-ray fluorescence(XRF)for elements with atomic numbers 62≤Z≤83 were measured at two excitation energies,18 keV and 23 keV,using a synchrotron radiation source at a beamline of the Synchrotron Light Center for Experimental Science and Applications in the Middle East(SESAME),Jordan.The experimentally measured results of the relative intensities were compared with the calculated results using the subshell fluorescence yield and the Coster-Kronig transition probabilities recommended by Campbell and the values based on the Dirac-Hartree-Slater model by Puri.The experimental and theoretical results are in agreement.In this work,L XRF relative intensities for the elements Sm,Gd,Tb,Er,Ta,W,Re,Hg,Pb and Bi at energies of 18 keV and 23 keV were measured.

X-RAY FLUORESCENCE SPECTRA ANALYSIS ON THE STRUCTURE AROUND Ti^(4+) OF BaO-SiO_2-B_2O_3-TiO_2 SYSTEM GLASSES

The structure around Ti^(4+) in Bao-SiO_2 -B_2O_3-TiO_2 had been studied by X-ray fluorescence spectra. The results show that the Ti^(4+) mainly exists in the [TiO_4] and enters the network of [SiO_4]. [TiO_4] has the tendency to change to [TiO_6] with the increase of TiO_2 con-tent. When the TiO_2 content increases to about 20mol% the tendency reaches its maximum.

XRF法测定涂料用钛白粉中元素含量的研究

研究采用压片制样-X射线荧光光谱测定技术,使用9种配制钛白粉作为校准样本,建立了一种能够同时测定钛白粉中6种元素成分的方法。研究中,实验深入探讨压片制样中制样压力和时间对元素含量检测结果的影响,并据此确认样品制备条件。同时,实验针对基体效应及谱线重叠干扰校正等问题进行研究,通过软件提供的多元线性回归分析模型,以经验法建立各元素分析的校准曲线,并基于3倍背景信号波动的标准偏差计算出各元素的检出限(3 s)。为了进一步验证方法的精密度,实验不同钛白粉样品进行测试,测定值的相对标准偏差(n=10)为0.4%~5.9%。实验结果表明,钛白粉X射线荧光光谱测定的关键条件方法,包括检出限、准确度及重复性等,均能满足日常分析检测的要求,对实验室的钛白粉检测工作具有重要的指导意义。

AAS、ICP-AES、ICP-MS及XRF测定地质样品中铜铅锌锰的对比研究

区域地球化学调查样品分析内容广泛,覆盖元素多,要求检测周期短,且样品中各元素含量变化大。作为地学实验工作者,在选择分析技术和方法时除了必须满足对分析质量要求外,还尽可能简便、快速和低成本、低污染。从分析方法检出限、准确度、精密度、线性范围、检测周期、化验成本以及对周围环境影响等方面,研究了AAS、ICP-AES、ICP-MS及XRF法测定1∶5万区域地质调查样品中的铜、铅、锌、锰4种元素的优缺点。通过方法实验表明：化验成本最低的是XRF法,每测试100个样品只需38.5元;分析效率最高的是ICP-MS法,每测试300个样品需19 h;检出限最低的是ICP-MS法,Cu 0.3μg/g、Pb 0.5μg/g、Zn 0.7μg/g、Mn 2.0μg/g;线性范围最宽的是ICP-AES法,Cu 2~5 000μg/g、Pb 15~5 000μg/g、Zn 2~5 000μg/g、Mn 13~5 000μg/g;Cu准确度最高的是ICP-AES法（Δlg w≤±0.062）,Pb准确度最高的是XRF法（Δlg w≤±0.030）,Zn准确度最高的是ICP-MS法（Δlg w≤±0.022）,Mn准确度最高的是XRF法（Δlg w≤±0.025）;Cu精密度最好的是ICP-AES法（RSD≤6.32%）,Pb精密度最好的是XRF法（RSD≤7.86%）,Zn精密度最好的是XRF法（RSD≤7.32%）,Mn精密度最好的是XRF法（RSD≤6.75%）;环境污染最小的是XRF法。经综合比较,选用XRF法。

钡永磁铁氧体半成品的XRF法定量测定

介绍了X射线荧光光谱法(XRF)在钡永磁铁氧体半成品分析中的应用,对比了粉末压片和玻璃熔片两种制样方法,使用熔片法制样建立标准曲线测定了其中的Fe、Ba等元素的含量。结果表明,Fe、Ba等元素含量的测定偏差<0.3%,平行测定9次相对标准偏差(RSD)可达到0.5%以下。与传统化学法测定相比,XRF可同时测定两种元素,测定每个样品仅需要1min,极大地提高了工作效率。

浅析铝土矿烧失量的差异在X-射线荧光光谱(XRF)分析中造成的影响

探讨了一水铝土矿与三水铝土矿烧失量的差异在X-射线荧光光谱(XRF)分析中造成的影响。采用实验的方式考察了硼酸锂熔融制样过程中铝土矿的烧失量损失情况,实验表明,在熔融过程中,烧失量越大的样品质量损失也越多。运用理论计算分析了烧失量损失对测定结果的影响,结果表明:当采用一水铝土矿绘制工作曲线测定三水铝土矿样品时,将导致三水铝土矿中各组分测定结果偏高;烧失量的差异对主量元素测定结果影响较大,而对微量元素测定结果影响较小;待测物质的烧失量与基准物质烧失量差异越大,测定结果的偏差也就越大。

基于XRF的紫金山铜矿床硫地质特征

福建紫金山铜矿床属高硫浅成中低温热液矿床,矿石中主要含铜矿物为蓝辉铜矿、铜蓝和硫砷铜矿等,且铜矿物与黄铁矿密切共生。由于铜矿石中硫含量较高,导致铜精矿中硫含量超标,w(S)/w(Cu)比值为2.0~2.1,远高于冶炼要求的1.15~1.20,影响其经济价值。使用X射线荧光(XRF)光谱分析对紫金山铜矿中S元素的分布进行数字化研究,查明硫的空间分布规律和赋存状态,划分铜矿石类型,为紫金山铜矿今后的采选工作提供参考。

Application of a Portable XRF Spectrometer for <i>In-Situ</i>and Nondestructive Investigation of Pigments in Two 15th Century Icons

A simple portable X-Ray Fluorescence (XRF) spectrometer was successfully used for in-situ and nondestructive identification of the painting materials in two 15th century icons from the Onufri Museum in Beart, Albania. The spectrometer is based on a low power X-ray tube, a thermoelectrically cooled Si PIN detector and the spectrum acquisition system. It was assembled and adjusted at our laboratory for the investigation of the icons. A small number of pigments were clearly identified by X-Ray Fluorescence (XRF) measurements in both icons. This includes Lead white for the white color, gold and yellow ochre for the yellow color, red lead, cinnabar and red ochre for the red color, as well as cooper based pigments for the green color. At the same time, the investigation raised some new questions that need further investigations by the use of additional analytical techniques. The results show that in both icons are used similar pigments, which are in accordance with the Byzantine icon painting tradition.

Soil Clay Mineralogical Phase Analysis of Ganges Floodplain Soils by XRD and XRF

Soil minerals study is vital in terms of investigating the major soil forming compounds and to find out the fate of minor and trace elements in soils. It is also essential for the soil-plant interaction purpose. To identify soil mineral phases especially clay minerals, X-ray diffraction (XRD) has been a popular technique. The clay mineralogical information of soils in Bangladesh is limited, especially in Ganges flood plain region (Agro Ecological Zone (AEZ) 12 and 13). Therefore, to overcome this limitation, in this study, we performed XRD analysis of <2 mm fractions soil samples of AEX 12 and 13. However, identifying mineralogical phases by XRD in <2 mm fractions soils is not so straight-forward due to many practical problems. We fully matched only two mineralogical phases in all the soil samples which is quartz and potassium-Aluminum-Silicate. However, the full XRD peaks indicate that more minerals are also present, but due to heterogeneity of soils samples, it is difficult to find other minerals phases by only XRD peak of <2 mm fractions. Therefore, to find more information about mineralogical phases, we performed XRF analysis that provides the elemental composition of minerals phase as oxide. XRF analysis indicated the presence of secondary minerals like illite and chlorite. The presence of high percentage Fe oxide not only indicated the iron mineral phase (goethite and ferrihydrite) but also indicated iron rich high charge smectite minerals (beidellite). The presence of iron rich smectite minerals in the Ganges sediments reported in several previous studies. Thus, we concluded that only XRD in <2 mm fractions of soils is not adequate to identify the mineralogical phases of soil samples. Others analyses like XRF, XRD in <2 μm fractions will be necessary to locate an entire image of soil mineralogical phases.

XRF Standardless Comparison of Mining Head and Tail Grades to Screen and Display Ore Processing Recoveries

Separation of target elements or minerals from their host rock or ore is essential to successful mining operation. The inevitable loss of a portion of the desired material that accompanies each step in the extraction process must be documented to develop the operational protocol. Superposition of the characteristic X-ray fluorescence spectra of head (crushed rock ore particles, pre-processing) and tail (post-processing particles) samples provides a direct visual comparison of relative peak sizes, and thereby the relative concentrations, of elements of interest. If the head and tail peaks are identical, none of the element was recovered in the extraction process. At the other extreme if the tail peak “flat lines”, i.e., there is no peak, there was 100% recovery of that element. Standardless visual comparison is valid if the same mass of identical starting material is incorporated into the head and tail sample analysis pucks, and XRF analytical conditions are identical. The considerable time and expense of acquiring and calibrating the standards associated with XRF analysis of 75 or more elements are avoided, a significant advantage during initial broad screening of an experimental extraction procedure. Full quantitation by XRF or an alternate technique can proceed at a later project stage, if desired. The approach retains and presents all features of the original data, thus eliminating questions about data quality, standards and their calibration, and data manipulation in processing from raw counts to concentrations in printout tables. This form of display is ideal for both the mining professional and such less technical groups as corporate staff, investors, regulators, and the public. Examples presented herein are for heap leaching;the protocol can be applied as well to any of the other traditional ore processing and beneficiation procedures, e.g., gravity concentration, magnetic and electrical separation, froth flotation, and ore sorting.

粉末压片-X射线荧光光谱法测定过磷酸钙中硫含量

硫是过磷酸钙中重要营养指标之一,为准确快速测定过磷酸钙中硫的含量,将过磷酸钙试样充分干燥后研磨至粒度小于74μm,采用硼酸镶边,在压力18 MPa条件下保压30 s,制成样片。通过在过磷酸钙样品中添加不同质量的纯物质硫酸钙(质量分数1.52%~17.21%),经过专用混匀设备混合均匀后,与试样压片相同条件下压制标准样片,作为过磷酸钙中硫的标准样品,制作硫标准曲线,曲线线性相关系数R 2为0.9995,采用经验系数法校正干扰,建立了粉末压片-波长色散X射线荧光光谱法测定过磷酸钙中硫含量的方法,方法检出限为0.002%;对3个不同硫含量的过磷酸钙样品重复测量7次,相对标准偏差(RSD)在1.4%~3.1%,方法精密度较好;同时用高温燃烧红外光谱法和电感耦合等离子发射光谱法测定样品,将测定结果进行对比,三者测定结果相对极差小于2.0%,无显著性差异。方法不需要对样品进行熔融或溶解,样品制备简单,数据准确度和稳定性好,分析效率高,适合于大批量样品中硫的测定。

X射线荧光光谱在石油炼制元素分析中的应用进展

石油原料中微量杂质元素在炼制过程会造成设备的腐蚀以及产品质量的下降,产品中的添加元素又是提升产品性能的关键,因此元素组成分析贯穿了整个石油炼制过程。伴随着硬件、软件上取得的显著技术进步,X射线荧光光谱(XRF)具备了快速、便捷、无损、覆盖元素多的特点,成为了石油化工领域元素分析应用中低碳、环保、最具有前景的普适性测试技术之一。介绍了近年来XRF技术的主要应用进展,综述了XRF在原油、汽油、柴油、润滑油、石油焦和催化剂等各个领域应用特点和问题,并总结了相关的标准方法及标准制订的变化趋势,对XRF在石油化工领域未来的应用发展趋势进行了展望。

波长色散型X射线荧光光谱法测定J矿山矿样中银、铜、铅、锌含量

采用波长色散型X射线荧光光谱法测定了J矿山矿石样品中的Ag、Cu、Pb、Zn,确定了粉末压片-校准曲线绘制-仪器测定等相关条件,并进行了抽样检测与常规化学分析方法比对。结果表明,该方法精密度好,方法比对结果满意,满足一般矿山的生产需求。由于其检测用时短、人力成本低的特点,可以在实际生产中取得良好的效果。

地质样品中痕量氯溴和硫的X射线荧光光谱法测定

报道了粉末压样 -X射线荧光光谱法测定地质样品中痕量Cl、Br、S的分析方法。采用水系沉积物、岩石和土壤等国家一级标准物质进行校准。实验表明 ,对于不同岩性样品中Br的分析 ,特别是当Br的含量低于 2 μg/g时 ,采用谱峰强度 (未扣除背景 )与背景强度的比进行校准所得到的结果 ,明显优于铑靶线的Compton散射线内标法 ,分析精度 (RSD ,n =6 )为 2 .4%～1 5 .3 % ,大多数优于 1 0 % ;平均值的相对误差低于 2 4 %。对于Cl的分析 ,只需对Ca的影响加以校正即可得到非常好的结果 ;不同样品中Cl的分析精度 (RSD ,n =6 )为 2 .1 %～ 1 3 .6 % ,大多数优于 5 % ;平均值的相对误差不大于 2 5 % ,多数优于 1 0 %。S的校准曲线的离散性较大 ,矿物学效应是影响S分析准确度的主要因素 ,其分析精度 (RSD ,n =6 )为 0 .87%～ 5 .6 % ,除个别样品外 ,平均值的相对误差优于 3 6 %。Cl和S均存在分析结果随测量时间 (次数 )的增加而增高的现象 ,必须在制样后立即测量。方法的检出限 (μg/g)Br、Cl、S分别为 0 .43、5 .8和 2 .2。

X射线荧光光谱分析稀土的研究进展

本文对近二十年来X射线荧光光谱仪在稀土分析方面的应用进行了综述。总结了环境、矿物、稀土富集物、单一稀土化合物、稀土金属、合金、稀土功能材料以及过程分析中稀土元素的X射线荧光光谱分析方法,检测方法涉及钢铁、有色金属、石油化工、地质、生物、电子材料等领域。展望了X射线荧光分析方法在稀土行业的应用前景。