Electrothermal volatilization flame and graphite furnace atomic absorption spectrometric investigations on the determination of calcium in gallium

T. Kántor, Bernard Radziuk, Bernhard Welz

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

Electrothermal volatilization flame atomic absorption spectrometry (ETV-FAAS) was used for element-specific detection in the vapour evolved during heating of a graphite furnace (GF). The studies, combined with graphite furnace atomic absorption spectrometry (GFAAS) and GF molecular absorption spectrometry (GFMAS) were intended to provide a better understanding of the volatilization mechanisms of calcium and gallium. Both elements were applied as minor and major components in nitric acid, hydrochloric acid and ammonium chloride media. Low heating rates (20-50°C/s) were used in the volatilization studies and the figures of merit were compared with those obtained from conventional pyrolysis curves. It was concluded that gallium, when introduced in nitric acid solution and at the 10 ng level, was evaporated between 900 and 1000°C in the form of Ga2O. When gallium was the matrix element (10 μg range) the major fraction vaporized in the 1120-2300°C range, producing Ga2O(g) and Ga(g) as major and minor components, respectively. A 1 ng mass of calcium vaporized rapidly above 1520°C with the evolution of atomic vapour, and this process overlapped in part with the vaporization of gallium matrix. Volatilization of gallium in the pyrolysis stage could be performed to a degree sufficient to eliminate the interference of up to 3 g l gallium in nitric acid medium on the determination of calcium using Zeeman-effect background correction. A detection limit of 0.06 μg g Ca in gallium was found if random contamination during dissolution was avoided. Microgram amounts of calcium introduced in HCl solution vaporized as CaCl2 and CaO, the oxide being formed by a heterogeneous phase hydrolysis. The addition of excess NH4Cl did not retard the hydrolysis of calcium chloride, while this additive promoted the vaporization of gallium in the form of chloride.

Original languageEnglish
Pages (from-to)875-891
Number of pages17
JournalSpectrochimica Acta - Part B Atomic Spectroscopy
Volume49
Issue number9
DOIs
Publication statusPublished - 1994

Fingerprint

Gallium
vaporizing
Graphite
Vaporization
gallium
furnaces
calcium
Calcium
flames
Furnaces
graphite
Nitric Acid
nitric acid
Nitric acid
Atomic absorption spectrometry
pyrolysis
hydrolysis
Hydrolysis
Pyrolysis
chlorides

ASJC Scopus subject areas

  • Analytical Chemistry
  • Spectroscopy

Cite this

@article{040ae3cddd65433282c1389ea275b68e,
title = "Electrothermal volatilization flame and graphite furnace atomic absorption spectrometric investigations on the determination of calcium in gallium",
abstract = "Electrothermal volatilization flame atomic absorption spectrometry (ETV-FAAS) was used for element-specific detection in the vapour evolved during heating of a graphite furnace (GF). The studies, combined with graphite furnace atomic absorption spectrometry (GFAAS) and GF molecular absorption spectrometry (GFMAS) were intended to provide a better understanding of the volatilization mechanisms of calcium and gallium. Both elements were applied as minor and major components in nitric acid, hydrochloric acid and ammonium chloride media. Low heating rates (20-50°C/s) were used in the volatilization studies and the figures of merit were compared with those obtained from conventional pyrolysis curves. It was concluded that gallium, when introduced in nitric acid solution and at the 10 ng level, was evaporated between 900 and 1000°C in the form of Ga2O. When gallium was the matrix element (10 μg range) the major fraction vaporized in the 1120-2300°C range, producing Ga2O(g) and Ga(g) as major and minor components, respectively. A 1 ng mass of calcium vaporized rapidly above 1520°C with the evolution of atomic vapour, and this process overlapped in part with the vaporization of gallium matrix. Volatilization of gallium in the pyrolysis stage could be performed to a degree sufficient to eliminate the interference of up to 3 g l gallium in nitric acid medium on the determination of calcium using Zeeman-effect background correction. A detection limit of 0.06 μg g Ca in gallium was found if random contamination during dissolution was avoided. Microgram amounts of calcium introduced in HCl solution vaporized as CaCl2 and CaO, the oxide being formed by a heterogeneous phase hydrolysis. The addition of excess NH4Cl did not retard the hydrolysis of calcium chloride, while this additive promoted the vaporization of gallium in the form of chloride.",
author = "T. K{\'a}ntor and Bernard Radziuk and Bernhard Welz",
year = "1994",
doi = "10.1016/0584-8547(94)80077-4",
language = "English",
volume = "49",
pages = "875--891",
journal = "Spectrochimica Acta, Part B: Atomic Spectroscopy",
issn = "0584-8547",
publisher = "Elsevier",
number = "9",

}

TY - JOUR

T1 - Electrothermal volatilization flame and graphite furnace atomic absorption spectrometric investigations on the determination of calcium in gallium

AU - Kántor, T.

AU - Radziuk, Bernard

AU - Welz, Bernhard

PY - 1994

Y1 - 1994

N2 - Electrothermal volatilization flame atomic absorption spectrometry (ETV-FAAS) was used for element-specific detection in the vapour evolved during heating of a graphite furnace (GF). The studies, combined with graphite furnace atomic absorption spectrometry (GFAAS) and GF molecular absorption spectrometry (GFMAS) were intended to provide a better understanding of the volatilization mechanisms of calcium and gallium. Both elements were applied as minor and major components in nitric acid, hydrochloric acid and ammonium chloride media. Low heating rates (20-50°C/s) were used in the volatilization studies and the figures of merit were compared with those obtained from conventional pyrolysis curves. It was concluded that gallium, when introduced in nitric acid solution and at the 10 ng level, was evaporated between 900 and 1000°C in the form of Ga2O. When gallium was the matrix element (10 μg range) the major fraction vaporized in the 1120-2300°C range, producing Ga2O(g) and Ga(g) as major and minor components, respectively. A 1 ng mass of calcium vaporized rapidly above 1520°C with the evolution of atomic vapour, and this process overlapped in part with the vaporization of gallium matrix. Volatilization of gallium in the pyrolysis stage could be performed to a degree sufficient to eliminate the interference of up to 3 g l gallium in nitric acid medium on the determination of calcium using Zeeman-effect background correction. A detection limit of 0.06 μg g Ca in gallium was found if random contamination during dissolution was avoided. Microgram amounts of calcium introduced in HCl solution vaporized as CaCl2 and CaO, the oxide being formed by a heterogeneous phase hydrolysis. The addition of excess NH4Cl did not retard the hydrolysis of calcium chloride, while this additive promoted the vaporization of gallium in the form of chloride.

AB - Electrothermal volatilization flame atomic absorption spectrometry (ETV-FAAS) was used for element-specific detection in the vapour evolved during heating of a graphite furnace (GF). The studies, combined with graphite furnace atomic absorption spectrometry (GFAAS) and GF molecular absorption spectrometry (GFMAS) were intended to provide a better understanding of the volatilization mechanisms of calcium and gallium. Both elements were applied as minor and major components in nitric acid, hydrochloric acid and ammonium chloride media. Low heating rates (20-50°C/s) were used in the volatilization studies and the figures of merit were compared with those obtained from conventional pyrolysis curves. It was concluded that gallium, when introduced in nitric acid solution and at the 10 ng level, was evaporated between 900 and 1000°C in the form of Ga2O. When gallium was the matrix element (10 μg range) the major fraction vaporized in the 1120-2300°C range, producing Ga2O(g) and Ga(g) as major and minor components, respectively. A 1 ng mass of calcium vaporized rapidly above 1520°C with the evolution of atomic vapour, and this process overlapped in part with the vaporization of gallium matrix. Volatilization of gallium in the pyrolysis stage could be performed to a degree sufficient to eliminate the interference of up to 3 g l gallium in nitric acid medium on the determination of calcium using Zeeman-effect background correction. A detection limit of 0.06 μg g Ca in gallium was found if random contamination during dissolution was avoided. Microgram amounts of calcium introduced in HCl solution vaporized as CaCl2 and CaO, the oxide being formed by a heterogeneous phase hydrolysis. The addition of excess NH4Cl did not retard the hydrolysis of calcium chloride, while this additive promoted the vaporization of gallium in the form of chloride.

UR - http://www.scopus.com/inward/record.url?scp=0028492379&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0028492379&partnerID=8YFLogxK

U2 - 10.1016/0584-8547(94)80077-4

DO - 10.1016/0584-8547(94)80077-4

M3 - Article

AN - SCOPUS:0028492379

VL - 49

SP - 875

EP - 891

JO - Spectrochimica Acta, Part B: Atomic Spectroscopy

JF - Spectrochimica Acta, Part B: Atomic Spectroscopy

SN - 0584-8547

IS - 9

ER -