ICPAES spectrometry

Line Coincidence Tables for Inductively Coupled Plasma Atomic Emission Spectrometry, Boumans, P.W.J.M, Pergamon Press, New York, 1984. The most comprehensive compilation available of sensitive lines for use in ICPAES, with listings of potential interferences. 

In the test method, the coal or coke to be analyzed is ashed under controlled conditions, digested by a mixture of aqua regia and hydrofluoric acid, and finally dissolved in 1% nitric acid. The concentration of individual trace elements is determined by either inductively coupled plasma-atomic emission spectrometry (ICPAES) or inductively coupled plasma-mass spectrometry (ICPMS). Selected elements that occur at concentrations below the detection limits of ICPAES can be analyzed quantitatively by graphite furnace atomic absorption spectrometry (GFAA). 

The techniques used (following the reconstitution or the leaching procedures) were chemiluminescence, DPASY ETAAS, ICPAES, ICMPS, INAA, IDMS and UV-visible spectrometry (Quevauviller, 1998b). 

Ultraviolet-visible (UV-Vis) spectrophotometric detectors are used to monitor chromatographic separations. However, this type of detection offers very little specificity. Element specific detectors are much more useful and important. Atomic absorption spectrometry (AAS), inductively coupled plasma-atomic emission spectroscopy (ICPAES) and inductively coupled plasma-mass spectrometry (ICP-MS) are often used in current studies. The highest sensitivity is achieved by graphite furnace-AAS and ICP-MS. The former is used off-line while the latter is coupled to the chromatographic column and is used on-line . 

A number of techniques have been used for the speciation of arsenic compounds. The most important has been the formation of volatile hydrides of several species, separation by gas chromatography and detection by AAS. HPLC has been used to separate arsenic species. Several types of detectors have been studied for the determination of arsenic species in the column effluent. These have included AAS both off- and on-line, ICPAES and ICP-MS. An important comparative study of coupled chromatography-atomic spectrometry methods for the determination of arsenic was published (Ebdon et al., 1988). Both GC and HPLC were used as separative methods, and the detectors were FAAS, flame atomic fluorescence spectrometry (FAFS) and ICPAES. The conclusions were (1) that hydride generation and cryogenic trapping with GC-FAAS was the most... 

Sulfate S is extracted from air-dry soil of <2 mm particle size with deionised water, using a soil to solution ratio of 1 5 and an extraction time of 17 hour at 25°C. This extracting solution will not displace adsorbed S, and will not necessarily dissolve all the gypsum that could be present. The extracted S is then determined in an aliquot of clear soil extract by inductively coupled plasma atomic emission spectrometry (ICPAES). In conjunction with vacuum optics, ICPAES is an efficient technique for the measurement of S in soil extracts. At the wavelength, 182.036 nm, there is virtually no interference from Ca2+. 

These methods include X-ray fluorescence spectrometry (XRF), inductively coupled plasma mass spectrometry (ICPMS), inductively coupled plasma atomic emission spectrometry (ICPAES), and atomic absorption spectrometry (AAS) (Welz and Sperling 1999) the respective detection limits of these methods are summarized in Table 19.1. Also listed are the detection limits for the metallochromic ligand complexes separated by reverse phase-high-per-formance liquid chromatography (RP-HPLC). These ligands include 4-(2-pyridyla-... 

Inductively Coupled Plasma Atomic Emission Spectrometry (ICPAES)... 

Detection limits are presented for 61 elements by ten analytical determinative methods FAAS flame atomic absorption spectrometry ETAAS electrothermal atomization atomic absorption spectrometry HGAAS hydride generation atomic absorption spectrometry including CVAAS cold vapor atomic absorption spectrometry for Hg ICPAES(PN) inductively coupled plasma atomic emission spectrometry utilizing a pneumatic nebulizer ICPAES(USN) inductively coupled plasma atomic emission spectrometry utilizing an ultrasonic nebulizer ICPMS inductively coupled plasma mass spectrometry Voltammetry TXRF total reflection X-ray fluorescence spectrometry INAA instrumental activation neutron analysis RNAA radiochemical separation neutron activation analysis also defined in list of acronyms. 

Treatment of ICPAES from different perspectives and to varying degrees of comprehensiveness appears in a number of chapters in volumes not solely dedicated to ICP-AES, but treating spectrometry and analysis in general. An early excellent chapter on ICP-AES is by Tschopel (1979) on plasma excitation in spectrochemical analysis, in Wilson and Wilson s Comprehensive Analytical Chemistry. A very brief historical introduction to ICP-AES, basic principles and considerations of absorption and emission lines, and applications to food analysis is in a book on modern food analysis (Ihnat (1984), and Van Loon (1985), in his practical analyst-oriented book on selected methods of trace analysis biological and environmental samples includes a chapter (pp. 19-52) on techniques and instrumentation including ICPAES. Moore (1989) (Introduction to Inductively Coupled Plasma Atomic Emission Spectrometry) provides... 

Determinative methods included under generic heading ofinductively coupled plasma atomic emission spectrometry are ICPAES, DCPAES, furnace ICPAES, etc., and include all variants. (2-7) Refer to footnotes to Table 2.7. 

A very recent volume edited by Berthed (2002) is on countercurrent chromatography - the support-free liquid stationary phase. Ebdon et al. (1987) review directly coupled liquid chromatogramphy-atomic spectroscopy. The review by Uden (1995) on element-specific chromatographic detection by atomic absorption, plasma atomic emission and plasma mass spectrometry covers the principles and applications of contemporary methods of element selective chromatographic detection utilizing AA, AES and MS. Flame and furnace are considered for GC and HPLC, while MIP emission is considered for GC and ICPAES for HPLC. Combinations of GC and HPLC with both MIPAES and ICPAES are covered and supercritical fluid chromatographic (SFC) and field flow fractionation (FFF) are also considered. 

Elemental speciation using mass spectrometry in conjunction with ICPAES is a latest advance in atomic spectroscopy, which is becoming popular in analytical research labs. Mason et al. ExxonMobil Research and Engineering) show how linking ICP-MS to various liquid chromatographic techniques has enabled determination of ppm levels of metals in hydrocarbons to ppb level measurements in refinery effluent streams. Hyphenated ICP-MS techniques were used to provide speciation information on nickel and vanadium in crude oils and assist in development of bioremediation options for selenium removal in wastewater treatment plants. Similar ICP-MS technique without sample demineralization was used by Lienemann, et al. Institut Francais du Petrole) to determine the trace and ultra-trace amounts of metals in crude oils and fractions. 

For measurement of heavy metals and other harmful trace elements in effluents and soHd waste, standard methods are available which generally utilise digestion and/or concentration followed by analysis using atomic absorption spectrometry (AAS), ICPAES, or increasingly ICP-MS. A comprehensive range of such methods has been produced by the US Enviroiunental Protection Agency (16). For a more detailed discussion of the use of atomic spectrometry in environmental analysis, the reader is referred to the comprehensive annual reviews of this topic produced as Atomic Spectrometry Updates [17-26]. 

Table 20.5 Plasma emission spectrometry (ICPAES or MIPAES).

ICPAES inductively coupled plasma atomic emission spectrometry... 

Atomic absorption spectrometry (AAS) has been widely used. Although flame AAS was useful in the past [45], electrothermal AAS is now preferred [30,46-48] as well as a simultaneous multielement atomic absorption continuum source coupled with a carbon furnace atomizer (SIMAAC) [49] or inductively coupled plasma atomic emission spectrometry (ICPAES) [39]. 

GFAAS graphite furnace atomic absorption spectrometry ICPAES inductively coupled plasma atomic emission spectrometry ICPMS inductively coupled plasma mass spectrometry INAA instrumental neutron activation analysis... 

Unfortunately, tin offers a poor sensitivity when determined directly by inductively coupled plasma atomic emission spectrometry (ICPAES) and requires the use of one or more preconcentration steps prior to its evaluation by this technique. The formation of volatile hydrides has been frequently used to improve sensitivity [100,101]. 

Direct determination after dilution with water can be used for the determination of tin in canned fruit juices [102]. For biological media, samples are decomposed by a nitric-perchloric acid mixture and analyzed after dilution by a standard addition technique. Tin hydride reduced by a sodium borohydride and trichloracetic acid solution are introduced into ICPAES after separation of liquid and excess hydrogen by an improved gas-liquid separator. Emission intensity is measured at 189.989 nm. The detection limit is 30 pg/mL [103]. Lower detection limits can be achieved by using ICPAES-mass spectrometry, [104]. 

Environmental samples offer a challenge to the analytical chemist because of the matrices involved. These include, among others, fresh- and seawater, sediments, marine and biological specimens, soil, and the atmosphere. For determining trace concentrations of vanadium in these complex matrices, preconcentration and separation techniques may be required prior to instrumental analysis. Hirayama et al. [14] summarize the various preconcentration and separation techniques including chelation, extraction, precipitation, coprecipitation, ion exchange in conjunction with the instrumental method of spectrometry, densitometry, flow injection, NAA, AAS, X-ray fluorescence, and inductively coupled plasma atomic emission spectrometry (ICPAES). While NAA offers great sensitivity and selectivity, its application is limited by the number of research reactors available worldwide. 

CNAA neutron activation analysis with preirradiation separation ETAAS electrothermal atomic absorption spectrometry EXAFS extended X-ray absorption fine-structure spectroscopy ICPAES inductively coupled plasma atomic emission spectrometry IGF-II immunoglobulin factor II... 

Determination of uranium in soil samples can be carried out by nondestructive analysis (NDA) methods that do not require separation of uranium (needed for alpha spectrometry or TIMS) or even digestion of the soil for analysis by ICPMS, ICPAES, or some other spectroscopic methods. These NDA methods can be divided into passive techniques that utilize the natural radioactive mission (gamma and x-ray) of the uranium and progeny radionuclides or active methods where neutrons or electromagnetic radiation are used to excite the uranium and the resultant emissions (gamma, x-rays, or neutrons) are monitored. In many cases, sample preparation is simpler for these nondestructive methods but the requiranent of a neutron source (from a nuclear reactor in many cases) or a radioactive source (x-ray or gamma) and relatively complex calibration and data interpretation procedures make the use of these techniques competitive only in some applications. In addition, the detection limits are usually inferior to the mass spectrometric techniques and the isotopic composition is not readily obtainable. 

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