Elemental analysis by mass spectrometry using an atmospheric-pressure microwave-induced plasma as an ion source

Thesis/Dissertation · Wed Jan 01 04:00:00 EST 1986

OSTI ID:7005699

Satzger, R D

An instrument was designed and built which is capable of performing rapid, sequential multi-element analyses. The instrument utilizes a microwave induced plasma as a source of singly charged monatomic positive ions. Ions generated in the plasma are sampled by an interface which produces an atomic beam which is transmitted and focused by using electrostatic ion lenses and filtered using a quadrupole mass spectrometer. Detection is accomplished in either analog or pulse counting modes depending on the current level of the response which is related to the concentration. The microwave cavity enables atmospheric pressure plasmas to be sustained in either argon or helium. An Ar plasma enables direct introduction of solution into the mass spectrometer using conventional nebulization techniques. Detection limits for most elements studied using the argon plasma are in the ng/mL range. Background interferences such as molecular oxides and critical operating parameters are discussed. A He plasma was investigated as an ion source for elements of higher ionization potential. Br, Cl and I were introduced as halomethanes in He. Improvements in the interface are discussed which reduce the molecular background by reduction of entrained atmospheric gases. Detection limits obtained for the halogens using the He plasma are in the pg/s range, indicating a high potential as an element selective detector for gas chromatography.

• Research Organization: Cincinnati Univ., OH (USA)
• OSTI ID: 7005699
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400102* -- Chemical & Spectral Procedures
ELECTROMAGNETIC RADIATION
ELEMENTS
HALOGENATED ALIPHATIC HYDROCARBONS
HALOGENS
MASS SPECTROSCOPY
MICROWAVE RADIATION
NONMETALS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
PLASMA
RADIATIONS
SPECTROSCOPY