Plasma emission spectrometer

Schematic diagram of an argon plasma emission spectrometer.

The application of the Spectroscan DC plasma emission spectrometer confirmed that for the determination of cadmium, chromium, copper, lead, nickel, and zinc in seawater the method was not sufficiently sensitive, as its detection limits just approach the levels found in seawater [731]. High concentrations of calcium and magnesium increased both the background and elemental line emission intensities. 

Nygaard [752] has evaluated the application of the Spectraspan DC plasma emission spectrometer as an analysis tool for the determination of trace heavy metals in seawater. Sodium, calcium, and magnesium in seawater are shown to increase both the background and elemental line emission intensities. Optimum analytical emission lines and detection limits for seven elements are reported in Table 5.8. 

Francesconi, K.A., P. Micks, R.A. Stockton, and K.J. Irgolic. 1985. Quantitative determination of arsenobe-taine, the major water-soluble arsenical in three species of crab, using high pressure liquid chromatography and an inductively coupled argon plasma emission spectrometer as the arsenic-specific detector. Chemosphere 14 1443-1453. 

The outline of the construction of a typical plasma emission spectrometer is to be seen in Figure 8.10. The example shown has an inductively coupled plasma, excitation source, but the outline would be similar were a dc source to be fitted. Different combinations of prisms and diffraction gratings may be used in the dispersion of the emitted radiation, and in the presentation of the analytical signal. Instruments are computerized in operation and make use of automatic sample handling. Sophisticated data handling packages are employed routinely to deal with interferences, and to provide for clarity in data output. 

Selecting an approach A nearby lab specializes in mass spectrometric analysis and can perform the EPA screening method for pesticides and other toxic chemicals. Your own lab just bought an inductively coupled plasma emission spectrometer and can analyze the water for heavy metals. 

The current generation of inductively coupled plasma emission spectrometers provide limits of detection in the range of 0.1-500pg L 1 in solution, a substantial degree of freedom from interferences and a capability for simultaneous multi-element determination facilitated by a directly proportional response between the signal and the concentration of the analyte over a range of about five orders of magnitude. 

These workers used an ARC 34000 inductively coupled plasma emission spectrometer with flow-injection hydride generation. The 189.04nm line (3nd order) was used for arsenic measurement. The flow-injection block and Buckler peristaltic pump, as described by Liversage et al. [125] were also used for the determination of arsenic by hydride generation. 

Detailed operating conditions for the inductively coupled plasma emission spectrometer have been described by Brzezinska et al. [126]. 

Energy levels of halogen atoms (F, Cl, Br, I) are so high that they emit ultraviolet radiation below 200 nm. This spectral region is called vacuum ultraviolet because radiation below 200 nm is absorbed by Oz, so spectrometers for the far-ultraviolet were customarily evacuated. Some plasma emission spectrometers are now purged with N2 to exclude air so that the region 130 to 200 nm is accessible and Cl, Br, I, P, and S can be analyzed.14... 

An inductively coupled plasma emission spectrometer does not require any lamps and can measure as many as —70 elements simultaneously. Color Plates 23 and 24 illustrate two designs for multielement analysis. In Plate 23, atomic emission enters the polychromator and... 

In contrast to gas chromatographic separations, which require the preparation of volatile derivatives of tin compounds, separations carried out by means of HPLC do not necessarily require preparations of derivatives. HPLC has been used in conjunction with several detection techniques, including photometers, atomic absorption spectrometers and direct current plasma emission spectrometers after hydride generation. Some recent studies have involved fluorimetric detection (Kleibohmer and Cammann, 1989) and hydride generation AAS. The latter has been applied to the quantification of TBT in coastal water. 

The beryllium acetylacetonate is separated in a gas chromatograph and injected into the helium plasma emission spectrometer. The detection limit is lOpg in a 30mL water sample and the standard deviation was 4.1% at lOng of beryllium. 

Measurement and control of low-flow rates are a requirement in such applications as fuel cells, purging, bioreactors, leak testing, and controlling the reference gas flow in chromatographs or in plasma-emission spectrometers. The most traditional and least expensive low-flow sensor is the variable-area flowmeter. It has a high rangeability (10 1) and requires little pressure drop. Due to its relatively low accuracy, it is limited to purge and leak-detection applications. 

Procedure Set up an inductively coupled plasma emission spectrometer according to manufacturer s instmctions, using the lead emission line at 220.35 nm. Calibrate the instmment using the Standard Lead Blank Solution and the Diluted Standard Lead Solution. Then analyze the Sample Preparation and the Control Lead Solution. The sample passes the test if the lead concentration found in the Sample Preparation is equal to or less than that in the Control Lead Solution. 

The outline of the construction of a plasma emission spectrometer may be inferred from figure 8.3 with a plasma source replacing the electrode system. Instruments are computerized and make use of automatic sample handling. 

The inductively coupled argon plasma emission spectrometer used for quantitative analysis of trace elements. 

Braman and Foreback succeeded in separating and quantitatively determining As(III), As(V), MMAA and DMAA by a procedure based on sodium borohydride reduction to the corresponding arsines with a dc helium plasma emission spectrometer as the detector. ... 

Spectrametrics, Inc. Plasma Emission Spectrometers for Atomic Analysis ... 

Any type of detector with a flow-through cell can be used for FIA. Photometric detectors are most often used in FIA (15-18, 25). However, many other analyses using fluorimeters (28, 29), refractometers (24), atomic absorption (30, 31), and inductively coupled plasma emission spectrometers (32) have been described. Electrochemical detectors based on potentiometry with ion-selective electrodes (15, 33), anodic stripping voltammetry (15, 34), potentiometric stripping (35), and amperometry (36) have also been used. 

Figure 2.3 Basic configuration of plasma emission spectrometers...

In the inductively coupled argon plasma emission spectrometer method, nickel, iron, and vanadium content of gas oil samples in the range from 0.1 to 100 mg/kg. Thus a 10-g sample of gas oil is charred with sulfuric acid and subsequently combusted to leave the ash residue. The resulting sulfates are then converted to their corresponding chloride salts to ensure complete solubility. A barium internal standard is added to the sample before analysis. In addition, the use of the ICAP method for the analysis of nickel, vanadium, and iron present counteracts the two basic issues arising from metals analysis. The most serious issue is the fact that these metals are partly or totally in the form of volatile, chemically stable porphyrin complexes and extreme conditions are needed to destroy the complexes without losing the metal through volatilization of the complex. The... 

Leaching of Pd from catalyst was determined by means of ICP-MS (Ion coupled plasma emission spectrometer-mass spectrometer ELAN 6000). From a sample taken in a hydrogenation experiment the solvent was first evaporated and then the remaining solids were dissolved into aqua regia (1 3, concentrated nitrogen acid hydrochloride acid). After dissolving, the sample was diluted with water prior ICP-MS analysis. 

Plasma emission spectrometers have shown a rapid growth. This holds also for NMR spectrometer sales because of new applications in biomedical research and more sophisticated experimental methods using increased computing power. Similarly, Raman spectroscopy, traditionally used in academic research, is gaining acceptance in industrial R D and quality control applications. Materials research and surface analysis in a variety of industries keeps the sales of electron microscopic, electron spectroscopic, ion spectroscopic, and X-ray instruments growing. Details of the various techniques on surface and interface characterization which are also important in R D of chemical sensors themselves, can be found in Chapter 3, Section 3.4.2. 

Plasma Emission Spectrometer as the Arsenic-Specific Detector. Chemosphere, 14, 1443. 

Trace element analyses are often required for the determination of toxic metals such as chromium, mercury and lead in environmental samples and for monitoring the workplace environment. Conventional methods requiring extraction and separation procedures are time consuming. However, recent developments in GC and HPLC interfaced to atomic absorption and plasma emission spectrometers have enabled on-line analyses to be carried out. Ideally, the GC or HPLC column should be connected directly to the spectrometer sample cell or sample area to avoid dilution and loss of resolution. In practice a short heated transfer line of stainless steel or silica is used which has an internal diameter smaller than the column i.d. 

A dozen or more instrument manufacturers currently offer plasma emission spectrometers. The designs, performance characteristics, and wavelength ranges of these instruments vary substantially. Most encompass the entire ultraviolet-visible spectrum, from 170 to 800 nm. A few instruments are equipped for vacuum operation, which extends the ultraviolet lo LSO to 160 nm. This short-wavciengih region is important because elements such as phosphorus, sulfur, and carbon have emission lines in this range. 

PMTs and linear photodiode array detectors are discussed in detail in Chapter 5. This section will cover the 2D array detectors used in arc/spark and plasma emission spectrometers. In order to take advantage of the 2D dispersion of wavelengths from an Echelle spectrometer, a 2D detector is required. The detector should consist of multiple... 

Plasma Emission Spectrometer as a Detector for Gas and Liquid Chromatographs... 

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