1988 Fiscal Year Final Research Report Summary
Pressurized Acid Vapor Decomposition of Highly Pure Silica and Determination of Impurities by One-drop Atomic Spectrometry
Project/Area Number |
62470033
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Research Category |
Grant-in-Aid for General Scientific Research (B)
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Allocation Type | Single-year Grants |
Research Field |
分析・地球化学
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Research Institution | Nagoya Institute of Technology |
Principal Investigator |
KOJIMA Isao Nagoya Institute of Technology, 工学部, 助教授 (60022620)
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Project Period (FY) |
1987 – 1988
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Keywords | Highly pure silica / One-drop method / Atomic spectrometry / Acid vapor decomposition / Teflon decomposition / Micro scale solvent extraction / Metal complexes / 抽出試薬 |
Research Abstract |
In a sealed double Teflon vessel with stainelss steel jacket, the purification of acids and the determination of highly pure silica with these purified acid vapors were simultaneously carried out at an elevated temperature. A significant decrease in the metal blank level even from the artificially contaminated acids containing 1 mg of each metal was obtained. Trace metal impurities (Na, Ca, Mg, Cu, Fe, Mm and Ti) in natural silica, "Specpure" silica from Johnson Matthey and highly pure and synthetic silica were well determined by "One-drop" flame atomic absorption and inductively coupled plasma atomic emission spectrometries, without any other concentration step before determination. Metals extracted as their complexes into organic solvents (CC1_4, CHC1_3, CH_2C1_2 and MIBK) were determined by "One-drop" flame atomic absorption spectrometry with injection volume of 30-40 ul and without deuterium background correction. Direct injection of organic extracts of more than 50 ul into an airacetylen flame gives an interesting signal profile, which depends on the kind of metals of interest (Cu(I,II), Cd, Co, Fe(II,III), Ni and Zn). On the other hand, only normal signal profiles are obtained irrespective of metals with a nitrous oxide-acetylene flame. This interesting signal profile of a metal seems to be related to the dissociation energy of the corresponding metal oxide. The method was successfully applied to the determination of copper in certified reference material from the National Institute for Environmental Studies (NIES-CRM, No. 9, Sargasso) and the results agreed well with the certified value.
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Research Products
(8 results)