特殊地质样品中钼同位素分析的化学前处理方法研究
Research on the Chemical Pretreatment for Mo Isotope Analysis of Special Geological Samples
查看参考文献52篇
文摘
|
Mo同位素的研究在地学领域应用广泛,它可以示踪Mo的全球循环、古海洋氧化还原条件、成矿过程、天体演化过程等。应用多接收电感耦合等离子体质谱法(MC-ICP-MS)分析Mo同位素比值前需对样品进行分离纯化,以富集Mo和去除Zr、Ru、Fe、Mn等干扰元素。处理某些Fe含量特别高且Ca含量也高的特殊地质样品(如含大量黄铁矿的钙质泥岩、钙质页岩等),若根据传统的阴阳离子交换树脂双柱法,需多次使用阳离子交换树脂分离Fe,步骤较繁琐且Mo回收率也会降低,而根据传统的阴离子交换树脂单柱法,使用1mol/L氢氟酸-0.5mol/L盐酸介质会产生较多CaF_2沉淀影响分离纯化效果。针对此类特殊地质样品,本实验使用同一阴离子树脂柱(AG1-X8,100~200目)对样品进行两次淋洗,第一次使用6mol/L盐酸,第二次使用1mol/L氢氟酸-0.1mol/L盐酸和6mol/L盐酸。结果表明Mo的回收率>96%,干扰元素的去除效果好,尤其是Ru的去除率接近100%,比原方法提高了约12%。对实际样品进行实验的结果也显示,Mo的回收率和干扰元素的去除都符合要求,δ~(98/95)Mo测定值与文献报道值一致。改进后的阴离子交换树脂单柱-二次淋洗法适用于Fe、Ca含量较高的特殊样品,降低了分析成本,也适用于绝大多数地质样品。 |
其他语种文摘
|
BACKGROUND:Mo isotopes have been widely used in the field of geosciences.They can be used to trace the global cycle of Mo,paleoocean redox conditions,mineralization processes,and astronomical evolution.Before the analysis of Mo isotope by multi-collector inductivity coupled plasma-mass spectrometry (MC-ICP-MS),the samples must be pretreated to enrich Mo and remove the interference elements (Zr,Ru,Fe and Mn).According to the traditional anion-cation exchange resin double-column method,it is necessary to use a cation-exchange resin multiple times to separate Fe.The steps are more complicated and the Mo recovery will be reduced.According to the traditional anion-exchange resin single-column method,1mol/L hydrofluoride acid-0.5mol/L hydrochloric acid medium will produce more CaF_2 precipitation and affect the separation and purification results.OBJECTIVES:To develop a new method for managing Ca-bearing geological samples with high Fe content before Mo isotope analysis.METHODS:For such special geological samples,the same anionic resin column (AG1-X8,100-200 mesh) was used to rinse the sample twice,the first time using 6mol/L hydrochloric acid,and the second time using 1mol/L hydrofluoride acid-0.1mol/L hydrochloric acid and 6mol/L hydrochloric acid.RESULTS:Results showed that Mo recovery was better than 96%,and the removal of the interference elements was good,especially the Ru removal rate,which was higher than the previous methods by 12%,up to 100%.The results of experiments on actual samples also showed that the recovery of Mo and the removal of interfering elements meet the requirements,and the measured values of δ~(98/95)Mo were consistent with those reported in the literature.CONCLUSIONS:The improved anion exchange resin single-column elution method is suitable for special samples with high Fe and Ca content,which reduces the analysis cost and is applicable to most geological samples. |
来源
|
岩矿测试
,2020,39(1):30-40 【核心库】
|
DOI
|
10.15898/j.cnki.11-2131/td.201906190087
|
关键词
|
Mo同位素
;
离子交换树脂法
;
化学前处理
;
高铁高钙地质样品
;
MC-ICP-MS
|
地址
|
1.
中国科学院地球化学研究所, 矿床地球化学国家重点实验室, 贵州, 贵阳, 550081
2.
中国科学院大学, 北京, 100049
|
语种
|
中文 |
文献类型
|
研究性论文 |
ISSN
|
0254-5357 |
学科
|
化学 |
基金
|
国家自然科学基金项目
|
文献收藏号
|
CSCD:6673826
|
参考文献 共
52
共3页
|
1.
朱祥坤. 非传统稳定同位素地球化学的创建与发展.
矿物岩石地球化学通报,2013,32(6):651-688
|
CSCD被引
57
次
|
|
|
|
2.
Malinovsky D. Variations in the isotopic composition of molybdenum in freshwater lake systems.
Chemical Geology,2007,236(3/4):181-198
|
CSCD被引
9
次
|
|
|
|
3.
Archer C. The isotopic signature of the global riverine molybdenum flux and anoxia in the ancient oceans.
Nature Geoscience,2008,1(9):597-600
|
CSCD被引
9
次
|
|
|
|
4.
Nagler T F. Molybdenum isotope fractionation in pelagic euxinia: Evidence from the modern Black and Baltic Seas.
Chemical Geology,2011,289(1/2):1-11
|
CSCD被引
16
次
|
|
|
|
5.
Noordmann J. Uranium and molybdenum isotope systematics in modern euxinic basins: Case studies from the central Baltic Sea and the Kyllaren Fjord ( Norway).
Chemical Geology,2015,396(9):182-195
|
CSCD被引
10
次
|
|
|
|
6.
Dahl T W. Molybdenum isotope fractionation and speciation in a euxinic lake-Testing ways to discern isotope fractionation processes in a sulfidic setting.
Chemical Geology,2017,460(5):84-92
|
CSCD被引
3
次
|
|
|
|
7.
Neely R A. Molybdenum isotope behaviour in groundwaters and terrestrial hydrothermal systems, Iceland.
Earth and Planetary Science Letters,2018,486(15):108-118
|
CSCD被引
2
次
|
|
|
|
8.
Siebert C. Molybdenum isotope record as a potential new proxy for paleoeanography.
Earth and Planetary Science Letters,2003,211(1/2):159-171
|
CSCD被引
36
次
|
|
|
|
9.
Arnold G L. Molybdenum isotope evidence for widespread anoxia in Mid-Proterozoic oceans.
Science,2004,304(5667):87-90
|
CSCD被引
50
次
|
|
|
|
10.
Lehmann B. Highly metalliferous carbonaceous shale and Early Cambrian seawater.
Geology,2007,35(5):403-406
|
CSCD被引
66
次
|
|
|
|
11.
蒋少涌. 华南寒武纪早期牛蹄塘组黑色岩系中Ni-Mo多金属硫化物矿层的Mo同位素组成讨论.
岩石矿物学杂志,2008,27(4):341-345
|
CSCD被引
19
次
|
|
|
|
12.
Kendall B. Uranium and molybdenum isotope evidence for an episode of widespread ocean oxygenation during the Late Ediacaran Period.
Geochimica et Cosmochimica Acta,2015,156(1):173-193
|
CSCD被引
26
次
|
|
|
|
13.
Kurzweil F. Coupled sulfur, iron and molybdenum isotope data from black shales of the Tepla-Barrandian unit argue against deep ocean oxygenation during the Ediacaran.
Geochimica et Cosmochimica Acta,2015,171(15):121-142
|
CSCD被引
8
次
|
|
|
|
14.
Wen H J. Reconstruction of Early Cambrian ocean chemistry from Mo isotopes.
Geochimica et Cosmochimica Acta,2015,164(1):1-16
|
CSCD被引
21
次
|
|
|
|
15.
Ruebsam W. Multiproxy reconstruction of oceanographic conditions in the Southern Epeiric Kupferschiefer Sea ( Late Permian ) based on redox-sensitive trace elements,molybdenum isotopes and biomarkers.
Gondwana Research,2017,44:205-218
|
CSCD被引
2
次
|
|
|
|
16.
Yin L. Rhenium-osmium and molybdenum isotope systematics of black shales from the Lower Cambrian Niutitang Formation, SW China: Evidence of a well oxygenated ocean at ca. 520Ma.
Chemical Geology,2018,499(5):26-42
|
CSCD被引
6
次
|
|
|
|
17.
Chen J B. Evaluation of paleomarine redox conditions using Mo-isotope data in low-[Mo] sediments: A case study from the Lower Triassic of South China.
Palaeogeography, Palaeoclimatology,Palaeoecology,2019,519(1):178-193
|
CSCD被引
2
次
|
|
|
|
18.
Duan Y. Molybdenum isotope evidence for mild environmental oxygenation before the Great Oxidation Event.
Geochimica et Cosmochimica Acta,2010,74(23):6655-6668
|
CSCD被引
13
次
|
|
|
|
19.
Wen H J. Molybdenum isotopic records across the Precambrian-Cambrian Boundary.
Geology,2011,39(8):775-778
|
CSCD被引
16
次
|
|
|
|
20.
Eroglu S. Geochemical stratigraphy, sedimentology, and Mo isotope systematics of the ca. 2.58-2.50 Ga-old Transvaal Supergroup carbonate platform,South Africa.
Precambrian Research,2015,266:27-46
|
CSCD被引
5
次
|
|
|
|
|