2004 Fiscal Year Final Research Report Summary
Evaluation of the amount of elements released from an ICP into the atmosphere and zero emission in ICP-MS
| Project/Area Number |
15550068
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Analytical chemistry
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| Research Institution | Fukui University of Technology |
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Principal Investigator |
TANAKA Tomokazu Fukui University of Technology, Faculty of Engineering, Associate Professor, 工学部, 助教授 (40236609)
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| Project Period (FY) |
2003 – 2004
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| Keywords | ICP-MS / low-pressure helium-ICP / zero emission / ultrasonic nebulizer / Langmuir probe / electron temperature / ionization efficiency / イオン化率 |
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| Research Abstract |
The emission of elements from ICP mass spectrometer In order to collect the elements passing through the duct of a mass spectrometer, a sampling system with a membrane filter was made. The filter was set in a commercial available holder used for decompression filtration. One end of a metallic pipe (2 mm i.d.) was brought near to the filter and the other end was inserted into the center of the duct. While a solution of 10 μg Yb/ml was introduced into plasma, a part of analyte passing through the duct was colleted on the filter for a period of 30 min. The sample particles collected on the filter was desorbed into 5 ml of 0.1 M HNO_3 by irradiating ultrasonic wave. Although the analyte in the sample solution was determined by GF-AAS, no peak was observed, and consequently, the amount of analyte emitted from ICP-MS could not be measured quantitatively. This is probably due to the use of the pipe with small inner diameter. It is necessary to quantitatively determine the amount of elements emitted from ICP into the environment by improving the sampling system.
Low-pressure helium-ICP-MS Since it was difficult to continuously introduce aqueous solutions into low-pressure helium-ICP, a ultrasonic nebulizer was constructed in our laboratory. The generated sample aerosol was transported to a desolvation unit by the nebulizer gas. A PTFE-capillary interface between the sample introduction system and plasma enabled the operation of the nebulizer under atmospheric pressure conditions and the stable introduction of sample solutions. The plasma diagnosis with a Langmuir probe was made. The electron temperature measured for low-pressure helium-ICP was superior to that for argon-ICP. These results suggest that the ionization of analytes in the low-pressure helium-ICP was enhanced by electron impact with high-energy electrons. It was found that low-pressure helium-ICP is a promising ion source for zero emission in ICP-MS.
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