Portable X-ray fluorescence in the assessment of rare earth element-enriched sedimentary phosphate deposits
Portable X-ray fluorescence in the assessment of rare earth element-enriched sedimentary phosphate deposits
复制标题
便携式 X 射线荧光法评估富稀土元素沉积磷酸盐矿床
DOI：
10.1144/geochem2012-180
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
Suzanne Paradis
中科院分区：
文献类型：
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作者：
G. Simandl;R. Fajber;Suzanne Paradis
磷矿是磷肥工业使用的主要原料来源，近年来，它们也被认为是稀土元素(REE)和氟(F)的潜在来源。基于对加拿大不列颠哥伦比亚省费尔尼组32个天然磷矿矿浆的便携式X射线荧光(PXRF)测量，该仪器能够提供与实验室数据相比具有可接受的精密度、准确度和良好的测定系数(R2≥0.85)的数据。结果表明，该仪器的测定系数为0.5≤R2<；对于Nd、Ce、La、Zr、W和Al，pXRF数据集与实验室数据集之间的偏差为0.85。从勘探地质学家的角度来看，使用工厂定标的pXRF测量磷和铁的精度已经足够高。手持式X射线荧光光谱分析中的Nd、Pr、Ce、La、Ba、Mo、Zr、Y、Sr、U、Rb、Zn、Ca、K、Al、Si和S的分析结果必须与实验室结果进行重新校准。使用工厂pXRF设置，轻稀土(La、Ce、Pr、Nd)相对于实验室结果被系统性高估，而Y被系统性低估。这项研究介绍了不列颠哥伦比亚省东南部含稀土沉积磷矿的定位调查(矿浆分析)的第一阶段。如果进行样品准备(到纸浆)和现场重新校准，pXRF可以识别富含稀土的磷矿岩带，并划定含有不可接受的有害元素(如铀)的带。
Phosphate deposits are the main source of raw materials used by the phosphate fertilizer industry and, in recent years, they have also been considered as potential sources of rare earth elements (REEs) and fluorine (F). Based on 160 portable XRF (pXRF) measurements taken on 32 pulps of naturally occurring phosphate rocks from the Fernie Formation (British Columbia, Canada) with a representative range of P and REE concentrations, the pXRF analyser was able to provide data with acceptable precision, accuracy, and excellent coefficients of determination (r2 ≥ 0.85) relative to the laboratory data for Ba, Mo, Y, Sr, U, Rb, Zn, Fe, Ca, P, Si and S. Results with coefficients of determination of 0.5 ≤ r2 < 0.85 between the pXRF and laboratory-derived datasets were achieved for Nd, Ce, La, Zr, W, and Al. From an exploration geologist’s point of view, P and Fe were measured accurately enough by pXRF using the factory-set calibration. Portable XRF analysis for Nd, Pr, Ce, La, Ba, Mo, Zr, Y, Sr, U, Rb, Zn, Ca, K, Al, Si and S had to be recalibrated relative to laboratory results. Using factory pXRF settings, light REEs (La, Ce, Pr, Nd) were subject to systematic overestimation relative to laboratory results whereas Y was subject to systematic underestimation. This study presents the first stage of an orientation survey (pulp analyses) for sedimentary phosphate occurrences containing REEs in southeastern British Columbia. If sample preparation (to pulps) and field recalibration are carried out, pXRF can identify zones of phosphate rocks enriched in REEs, and delimit zones with unacceptable levels of deleterious elements, such as uranium.