| Summary: | 博士 === 國立臺灣大學 === 海洋學系 === 84 === Column pre-concentration techniques have been used intensively
for the determination of trace elements in seawater, but
unfortunately most of the previous procedures were developed on
the trial and error basis or simply by experience. It was the
purpose of this thesis to establish a theoretical model to fit
the experimental data so as to set up the optimal conditions
for the pre-concentration columns. A cut-plate technique and a
breakthrough experiment were employed to examine the
distribution of the analyte along the column and the efficiency
when applying under different ionic strengths, flow rates,
column dimensions. Using these two techniques it was able to
set up a basic exponential model to describe the efficiency of
the pre-concentration. Two types of the pre- concentration
columns were studied in the present work namely, the Chelex-100
chelating ion-exchange column and the Sep-Pak C18 adsorption
cartridge. The derivation of the efficiency- prediction
equations with specific mathematical coefficients for selected
elements have been demonstrated. Based on the prediction of
these equations, the present work has developed several ship-
board pre-concentration procedures for the analysis of Cd, Cu,
Co, Ni, Zn in seawater using the Chelex-100 column. Manual and
automated procedures were also developed for the pre-
concentrate nitrite and ferrous ions for the Sep-Pak C18
cartridge. All those methods were performed on the cruises of
the R/V Ocean Researcher I to the west Philippine Sea and the
South China Sea. The availability of applying the efficiency-
prediction equations and the effectiveness of the recommended
procedures have been fully proven. The proposed model may be
regarded as a potential tool for the further development of
methods for the determination of other trace materials in
seawater.
|
|---|
