Tracey Jacksier

Sealed inductively coupled plasma atomic emission spectrometry: instrumentation development

Instrumentation for the analytical use of a sealed and static inductively coupled plasma atomic emission system is described for the analysis of permanent and reactive gases. Discharge container construction, heat dissipation from sealed containers and the connection of the discharge container to a stainless-steel gas handling system for the introduction of standard gas mixtures are discussed. The system is applied to the determination of arsine in a gas stream.

Determination of iron and nickel in electronic grade chlorine by sealed inductively coupled plasma atomic emission spectrometry

A sealed inductively coupled plasma was used to determine the concentration of Fe and Ni in electronic grade chlorine. Since the discharge was formed inside a quartz container, factors such as toxicity, corrosion and contamination were not of primary concern. The system was calibrated for iron using two different standard materials, a ferrocene permeation tube and iron pentacarbonyl in argon. Under flowing conditions the detection limits (3σb) were 290 and 20 pg ml–1 for iron pentacarbonyl and ferrocene, respectively. A nickelocene permeation tube was used for the determination of Ni that resulted in a detection limit (3σb) of 9 pg ml–1. Parameters that affect the signal intensity and reproducibility, such as forward power, wash-out time, flow rate and external cooling, were optimized.

Atomic Emission of Chlorine: Spectra from 200 to 900 nm by Sealed Inductively Coupled Plasma-Atomic Emission Spectroscopy

Eighty-seven atomic chlorine lines and chlorine molecular spectra emitted in the 200–900 nm wavelength range are identified in a pure chlorine discharge generated at atmospheric pressure in a sealed inductively coupled plasma. Only small quantities of chlorine are needed for spectral evaluation because the flow rate is typically less than 20 mL/min.

Discharge container for the analysis of arsine by sealed inductively coupled plasma atomic emission spectroscopy

Abstract A discharge container suitable for the formation of an inductively coupled plasma discharge that contains high concentrations of a thermally decomposable elemental hydride (i.e. arsine) is described for spectrochemical analysis. This reusable container can support a discharge at pressures above and below atmospheric pressure in either low flow or static modes. The container geometry also prevents grounding of the radio frequency plasma discharge to the gas handling system.

Atomic Emission Spectra of Xenon, Krypton, and Neon: Spectra from 200 to 900 nm by Sealed Inductively Coupled Plasma/Atomic Emission Spectroscopy

The emission spectra of pure xenon, krypton, and neon are reported over the spectral range of 200 to 900 nm from an enclosed inductively coupled plasma discharge operated at atmospheric pressure and 350 W.

Qualitative analysis of arsine by sealed inductively coupled plasma atomic emission spectrometry

Parameter optimization of a sealed inductively coupled plasma and the qualitative analysis of arsine are described. The choice and role of an additive gas, effect of flow rate, discharge container size and geometry, r.f. power and signal reproducibility are discussed. The qualitative determination of C, Fe, Ge, Mg, Mo, Ni, Sn and V impurities in arsine is established.

Quantitative analysis of electronic-grade anhydrous hydrogen chloride by sealed inductively coupled plasma atomic emission spectroscopy

Anhydrous hydrogen chloride at concentrations of up to 100% has been introduced into a sealed inductively coupled plasma system for quantitative spectrochemical analysis. Vapour-phase sampling of monobutyltin trichloride was developed to calibrate tin and carbon. The addition of chlorine as a modifier gas was required in a ratio of 1:1 to maintain stable and reproducible emission signals. Under flowing conditions detection limits for tin and carbon were 49 and 271 (ng g–1), respectively, in a 16% v/v HCl–Cl2 argon plasma. Impurities identified qualitatively included Al, C, Ca, Cr, Fe, Ni and Sn. In addition, the bulk temperature of the plasma was determined to be 10 500 ± 1500 K.

Compound-Specific Sulfur Isotope Analysis of Petroleum Gases

We describe a simple, sensitive, and robust method for sulfur isotope ratio (34S/32S) analysis of ppm-level organic sulfur compounds (OSCs) in the presence of percent-level H2S. The method uses a gas chromatograph (GC) coupled with a multicollector inductively coupled plasma mass spectrometer (MC-ICPMS). The GC, equipped with a gas inlet and a valve that transfers the H2S to a thermal conductivity detector (TCD), enables a precise heart cut and prevents the saturation of the MC-ICPMS. The sensitivity and accuracy of the method are better than 0.3‰ for OSCs at a concentration of 25 pmol or 1.4 ppm, and better than 0.5‰ for concentrations ≥0.7 ppm of OSCs. An order of magnitude increase in sensitivity, with no effect on accuracy, can be achieved if the loop volume (0.5 mL) is changed to 5 mL. High concentrations of methane (95% v/v) and/or H2S (20% v/v) had no effect (within 0.5‰) on the precision and accuracy of the gas sample containing 2 ppm of OSCs after heart cut. The applicability and robustness of this method are demonstrated on a gas sample (10% v/v H2S) that was produced by pyrolysis of sulfur-rich kerogen. The results show good precision and reveal sulfur isotope variability between individual OSCs that may represent key processes during formation and degradation of OSCs.