Investigation of X-Ray Flourescence spectrometer to replace Aqua Regia digestion for the measurement of soil heavy metals

• Main Authors: Lin, Hung-Hsuan, 林宏軒
• Other Authors: Yu, Wu-Chou
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/y23gbd

碩士 === 國立屏東科技大學 === 環境工程與科學系所 === 106 === As a highly accurate quantitative method of determining the contents of heavy metal in soil, Aqua Regia digestion is a standard method in Taiwan, Digestion, a primary quantitative method, is accurate but a relatively high in cost and time consumption approach in deterimining the contents of heavy metals in soils. In contrast, X-Ray Fluorescence Spectrometer (XRF) is a lower cost and less time consuming method, However, the sample matrix is often affected by moisture or sample inhomogeneity, which often results in poor correlation between screening data and laboratory data. Heterogeneous disturbance in samples leads to poor correlations between measured and experimental data. This study explored the reliability and accuracy of X-Ray Fluorescence in rapid screening for heavy metals in soil. A total of 120 soil samples were acquired from Eastern and Western Taiwan. After the on-site X-Ray Fluorescence screening was completed, the samples were preprocessed and filtered through 10- and 100-mesh screens. The metals were converted to soluble ions through Aqua Regia digestion. Subsequently, inductively coupled plasma-atomic emission spectroscopy was employed to analyze the chromium, copper, nickel, lead, and zinc contents. A comparison of the two employed methods revealed a significant positive correlation between the measured and experimental data regarding the five studied elements. The R2 was 0.82~0.85 for the 10-mesh preprocessing results of chromium, copper, and nickel in Eastern Taiwan, 0.87 for the 100-mesh preprocessing result of nickel in Eastern Taiwan, and R2>0.90 for the remaining results.