Dissertation/Thesis Abstract

Nickel Atomization Studies on a Tungsten Filament Electrothermal Atomizer
by Oppong, Harriet Akyemfoah, M.S., Southern Illinois University at Edwardsville, 2014, 37; 1571642
Abstract (Summary)

A locally built portable tungsten filament electrothermal atomic absorption spectrophotometer was used to develop a method for the determination of nickel. The instrument used a 150 W tungsten coil extracted from a commercial light bulb as an atomizer. The power supply for the instrument was varied whilst all other components of the instrument remained unchanged. The power supplies were operated in four different modes; current, power, voltage 1, and voltage 2. The modes were evaluated to identify which one yielded the best sensitivity. The methods of quantification of the results were integrated absorbance and peak height. The quantification method of our instrument was evaluated based on a mathematical model proposed by Sturgeon for a graphite furnace atomizer.

Voltage 2 had the fastest heating rate, it showed a heating rate of 3930 K/s, recorded the lowest limit of detection of 68.35 ± 0.0037 ng/mL for area and 71.9 ± 0.015 ng/mL for peak height with a sensitivity of 0.0705 ng/mL. It was the most sensitive of the four modes. Power, voltage 1 and current followed in order of decreasing sensitivities with sensitivity values of 0.078 ng/mL, 0.0859 ng/mL and 0.1055 ng/mL respectively. The limits of detection followed the same trend as the sensitivity. However, for the heating rate, voltage 1 was faster followed by power and finally current.

This paper's results were comparable to that proposed by Sturgeon in terms of effects of analyte concentration and the absorbance generated even though the atomizers and instruments setup were completely different.

Indexing (document details)
Advisor: Navarre, Edward
Commitee: Jones, Myron, Patrick, Tim
School: Southern Illinois University at Edwardsville
Department: Chemistry
School Location: United States -- Illinois
Source: MAI 54/02M(E), Masters Abstracts International
Source Type: DISSERTATION
Subjects: Analytical chemistry
Keywords: Electrothermal atomizer, Nickel, Tungsten
Publication Number: 1571642
ISBN: 9781321434989
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