Lead determination by flame atomic absorption spectrometry using a slotted quartz tube atom trap and metal coatings

Download

index.pdf

Date

2009

Author

Demirtaş, İlknur

Metadata

Show full item record

Item Usage Stats

169
views

83
downloads

Flame Atomic Absorption Spectrometry (FAAS) still keeps its importance despite the relatively low sensitivity; because it is a simple and economical technique for determination of metals. In recent years atom traps have been developed to increase the sensitivity of FAAS. Although the detection limit of FAAS is only at the level of mg/L, with the use of atom traps it can reach to ng/mL. Slotted quartz tube (SQT) is one of these atom traps, it is applied for determination of volatile elements; it is economical, commercially available and easy to use. In this study, a sensitive analytical method has been developed for the determination of lead with the help of SQT. Regarding the angle between the two slots of SQT, 120° and 180° configurations were used and the results were compared. There were three modes of SQT used. The first application was for providing longer residence time of analyte atoms in the measurement zone; 3 fold sensitivity enhancement was observed. The second mode was the usage of SQT for preconcentration of lead atoms. In the presence of a lean air-acetylene flame, analyte atoms were trapped in the inner surface of SQT for a few minutes. Then, by the help of a small volume (10-50 μL) of Methyl isobutyl ketone (MIBK), analyte atoms were revolatilized and a rapid atomization took place. Using this mode, a sensitivity enhancement of 574 was obtained at a rather low (3.9 mL/min) suction rate; 1320 fold improvement was reached at higher sample suction rate (7.4 mL/min) for 5.0 min collection. The last mode involves coating of the inner surface of SQT with several kinds of transition metals. The best sensitivity enhancement, 1650 fold, was obtained by the Ta coated SQT. In addition, effects of some elements and anions on Pb signal in Tacoated-SQT-AT-FAAS were examined. Final step consists of surface analysis; chemical nature of Pb trapped on quartz and Ta surface, and the chemical nature of Ta on quartz surface were investigated by X-ray Photoelectron Spectroscopy (XPS) and Raman Spectroscopy.

Subject Keywords

Chemistry.

URI

http://etd.lib.metu.edu.tr/upload/3/12610794/index.pdf
https://hdl.handle.net/11511/18649

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Lead determination at ng/mL level by flame atomic absorption spectrometry using a tantalum coated slotted quartz tube atom trap Demirtas, Ilknur; BAKIRDERE, Sezgin; Ataman, Osman Yavuz (2015-06-01) Flame atomic absorption spectrometry (FAAS) still keeps its importance despite the relatively low sensitivity; because it is a simple and economical technique for determination of metals. In recent years, atom traps have been developed to increase the sensitivity of FAAS. Although the detection limit of FAAS is only at the level of mu g/mL, with the use of atom traps it can reach to ng/mL. Slotted quartz tube (SQT) is one of the atom traps used to improve sensitivity. In atom trapping mode of SQT, analyte i...
On-line preconcentration, speciation and determination of chromium by flame atomic absorption spectrometry(faas) and chemiluminescence Sürdem, Sedat; Volkan, Mürvet; Department of Chemistry (2004) Toxicological studies have shown that the degree of toxicity of some elements depends on the chemical form in which the element is present. Chromium (III) is considered as an essential micronutrient for human whereas chromium (VI) is a potentially carcinogenic agent. So the speciation of inorganic chromium in environmental samples is required for accurate assessment of pollution levels. The chromium content in natural water is usually very low, and a preconcentration is often necessary prior to the determin...
Tellurium determination by flame atomic absorption spectrometry using a slotted quartz tube atom trap and metal coatings Osmanbaşoğlu, Mahmut; Ataman, Osman Yavuz; Department of Chemistry (2011) Flame Atomic Absorption Spectroscopy (FAAS) has lover sensitivity than similar analytical methods, however it has an important place for analysis due to its easy application and economic practicability especially in metal determinations. In order to increase the sensitivity of FAAS from mg/L level to ng/L level, various atom trap systems have been used. One of these atom traps, Slotted Quartz Tube (SQT), which is easy, economical and useful for volatile element determination, is used in this study as a sens...
Asymmetric synthesis of chiral camphor fused pyridine type novel organocatalysts Küçükdişli, Murat; Tanyeli, Cihangir; Department of Chemistry (2009) Chiral pyridines as organocatalysts have been used in asymmetric organic synthesis in recent years. The asymmetric synthesis of camphor fused pyridine type novel organocatalysts were perfomed starting from cheap and easily available natural (+)-camphor. Using camphor fused pyridine skeleton, six organocatalysts 29, 32, 33, 38, 40, and 41were successfully synthesized. The first four nucleophilic and Lewis base catalysts 29, 32, and 33 are different P-oxides and P,N-dioxides which were tested in allylation of...
CATALYTIC CHARACTERISTICS OF MASSIVE AND LOADED SULFONIC RESINS IN THE SYNTHESIS OF ETHYL tert-BUTYL ETHER AT ATMOSPHERIC AND INCREASED PRESSURE Vlasenko, N. V.; Kochkin, Yu. N.; Strizhak, P. E.; Doğu, Timur; DOĞU, GÜLŞEN; OKTAR, NURAY; Degirmenci, L. (Springer Science and Business Media LLC, 2010-11-01) The catalytic characteristics of massive and loaded sulfonic resins in the synthesis of ethyl tert-butyl ether at atmospheric and increased pressures have been compared. It has been established that massive sulfonic resins are more active than loaded resins at atmospheric pressure. At higher pressures, on the other hand, the activity and selectivity of catalysts are greater the lower the content of polymer as a result of the increased effectiveness of the acid centers.

Citation Formats

İ. Demirtaş, “Lead determination by flame atomic absorption spectrometry using a slotted quartz tube atom trap and metal coatings,” M.S. - Master of Science, Middle East Technical University, 2009.