X Ashing Conditions of Lead-Accumulating Blechnum niponicum for X-Ray Fluorescence Spectrometry Hirofumi KODERA, Tomoko UEYAMA, Hiroshi NISHIOKA and Yasuji MURAMATSU Copyright The Discussion Group of X-Ray Analysis, The Japan Society for Analytical Chemistry
X Ashing Conditions of Lead-Accumulating Blechnum niponicum for X-Ray Fluorescence Spectrometry Hirofumi KODERA, Tomoko UEYAMA, Hiroshi NISHIOKA, and Yasuji MURAMATSU, Graduate School of Engineering, University of Hyogo 2167 Shosha, Himeji, Hyogo 671-221, Japan Faculty of Engineering, Himeji Institute of Technology 2167 Shosha, Himeji, Hyogo 671-221, Japan corresponding author: et5z12@steng.u-hyogo.ac.jp present address: Hitachi ULSI Systems Co., Ltd. 5-22-1 Josuihon-cho, Kodaira-shi, Tokyo 187-8522, Japan (Received 18 December 26, Accepted 2 December 26) To develop a quantitative analysis of heavy metals (Pb and Zn) in Blechnum niponicum using fluorescent X-ray spectrometry (XRF), ashing conditions of the plant samples are evaluated with an electric furnace and a microwave furnace. In the electric furnace method, the ashing conditions are optimized as 7 o C for 5 hr. Although the further optimization of the ashing conditions with the microwave furnace should be necessary, ashing with the microwave furnace can be utilized for the sample ashing. It can be confirmed that ashing is a useful sample treatment for XRF measurements of Pb and Zn in Blechnum niponicum. [Key words] XRF, Ashing, Blechnum niponicum, Lead, Zinc, Phytoremediation Pb Zn X 2167 671-221 2167 671-221 corresponding author: et5z12@steng.u-hyogo.ac.jp : LSI 5-22-1 187-8522 38 249 Adv. X-Ray. Chem. Anal., Japan 38, pp.249-258 (27)
X 7 5 7 3 X X 1. phytoremediation 1 hyperaccumulator 1 mg kg -1 1 mg kg -1 1 mg kg -1 2 15 3 Blechnum niponicum mg kg -1 4 25 38
AAS / ICP-AES/MS 1. g 3 4 X XRF XRF 212 3 µm XRF 5 6 XRF, 2. 2.1 2 1. g 7 5 SiC 7 85.8 g 7 = 85 3 21 1. g.55 g 7 kgf cm --2 2 mm φ 2 mm T X 7 5 7 3 5.618.16 g RSD =.157 %.65.376 g 38 251
Table 1 Quantity of lead and zinc which are added to the 1. g dried samples and the concentrations in the samples. Standard sample # 1 2 3 4 5 Pb /µg.2.5 1. 2. 3. (concentration / mg kg -1 ) (2) (5) (1) (2) (3) Zn /µg.1.2.5 1. 1.5 (concentration / mg kg -1 ) (1) (2) (5) (1) (15) absorbance.1.8.6.4 y = 3. 1-5 x + 5. 1-3 R 2 =.9842 1.2 1.8.6.4 y = 6. 1-4 x +.2 R 2 =.9357.2.2 1 2 3 4 5 1 15 2 Pb concentration / mg kg --1 Zn concentration / mg kg --1 Fig.1 Calibration curve for determination of Pb (left panel) and Zn (right) concentrations in ashed plant samples using the atomic absorption spectrometry (AAS). RSD=4.22 % Pb Zn 1. g Table 1 Pb Zn 1 mg L -1 1. g 7 5 7 3.55 g X Pb Zn Fig.1 2.2 X Zn Kα Pb Lβ X X 252 38
Table 2 Measurement conditions of X-ray fluorescence spectrometry in the regions of Zn Kα and Pb Lβ using RIX2. X-ray tube Tube voltage Tube current Analyzing crystal Atmosphere Collimator Sample spin Rh target 5 kv 5 ma LiF(2) vacuum (.1 Torr) 1 mm diameter on Element Pb Zn Spectrum Lβ Kα Peak position 28.24 deg (4 sec) 41.78 deg (4 sec) Background point 1 27.64 deg (1 sec) 41.18 deg (1 sec) Background point 2 28.84 deg (1 sec) 42.38 deg (1 sec) Rigaku RIX2 LiF(2) Pb Pb Lα Pb Lβ Pteris vittata 7 As Kα Pb Lα X Pb Zn X.6 INT X Table 2 3. 3.1 3, 5, 6, 65, 7, 75, 8, 9 1 Pb Lβ Zn Kα Fig.2 Pb 7 Zn 75 X X 75 38 253
25 X-ray intensity / cps 2 15 1 5 ZnKα PbLβ 2 4 6 8 1 Ashing temperature / Fig.2 Ashing-temperature-dependence on the fluorescent X-ray intensity (Zn Kα, Pb Lβ ) of the ashed plant samples. Ashing time is fixed at 1 hr. X-ray intensity / cps 25 2 15 1 5 ZnKα PbLβ 1 2 3 4 5 6 7 8 9 1 11 Ashing time / hour Fig.3 Ashing-time-dependence on the fluorescent X-ray intensity (Zn Kα, Pb Lβ ) of the ashed plant samples. Ashing temperature was fixed at 7. Pb Zn 7 7 1 3 5 7 1 X Fig.3 Pb Zn 5 X 5 3.2 X Pb Zn Fig.4 254 38
3 2 X-ray intensity / cps 25 2 15 1 5 y =.81x + 31.5 R 2 =.9983 y =.72x + 19.3 R 2 =.9966 E.F. M.W. 15 1 5 y =.92x + 196 R 2 =.9457 y =.81x + 154 R 2 =.952 E.F. M.W. 1 2 3 4 Pb concentration / mg kg -1 5 1 15 2 Zn concentration / mg kg -1 Fig.4 Calibration curve for determination of Pb (left panel) and Zn (right) concentrations in ashed plant samples using the X-ray fluorescence spectrometry. The samples were ashed by an electric furnace (EF) and a microwave (MW) methods. 5 Pb 3 Zn 2 X Pb Zn mg kg -1 Pb Zn X 7 3 5 Table 3 4 sample 1-5 Pb Zn Table 3 Table 4 (Fig. 1) XRF AAS R. E. (XRF) (AAS) /(XRF) 1 % mg kg -1 1 % mg kg -1 1% XRF AAS Pb Zn X Pb Zn 38 255
Table 3 Quantitative results of lead and zinc in Blechnum niponicum samples ashed with an electric furnace method. Sample # Pb concentration / mg kg -1 Zn concentration / mg kg -1 R.E. / % XRF AAS XRF AAS R.E./ % 1 97 757 17 13 1115 8.3 2 1998 281 4.2 79 835 5.7 3 2785 2757 1. 34 14 59 4 1922 2214 15 88 789 1.3 5 3723 3773 1.3 89 824 7.4 6* 58.1 3.3 *: sample picked at the non-mining area Table 4 Quantitative results of lead and zinc in Blechnum niponicum samples ashed with a microwave method. Sample # Pb concentration / mg kg -1 Zn concentration / mg kg -1 R.E. / % XRF AAS XRF AAS R.E./ % 1 17 757 25 138 1115 7.4 2 1889 281 1 726 835 15 3 2672 2757 3.2 337 14 58 4 2185 2214 1.3 868 789 9.1 5 3741 3773.8 881 824 6.5 6* 134.1 92.5 *: sample picked at the non-mining area Table 3 4 Sample 6 Pb Zn 1 2 Table 3 XRF Pb Zn Fig.5 mg kg -1 Pb mg kg -1 Zn Pb Zn AAS AAS 4 256 38
Pb concentration / mg kg -1 5 4 3 2 1 5 1 15 Zn concentration / mg kg -1 Fig.5 Correlation between lead and zinc concentration in Blechnum niponicum samples. XRF 5 XRF 1 15 XRF 4. Pb, Zn X 1. g 7 5 7 85 7 3 Pb Zn XRF Pb Zn Pb Zn AAS mg/kg -1 1 % XRF AAS Pb 38 257
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