DETERMINATION OF ALUMINIUM

DETERMINATION OF ALUMINIUM BY GAS CHROMATOGRAPHIC ANALYSIS OF ITS TRIS (ACETYLACETONATO) COMPLEX... 

Full details are given for the determination of aluminium by this method. Many other metals may be determined by this same procedure, but in many cases complexometric titration offers a simpler method of determination. In cases where the oxine method offers advantages, the experimental procedure may be readily adapted from the details given for aluminium. 

Determination of aluminium. Prepare a 2 per cent solution of 8-hydroxyquinoline [see Section 11.11(c)] in 2M acetic acid add ammonia solution until a slight precipitate persists, then re-dissolve it by warming the solution. 

DETERMINATION OF ALUMINIUM AS THE 8-HYDROXYQUINOLATE, AI(C,H60N)3> WITH PRECIPITATION FROM HOMOGENEOUS SOLUTION... 

The procedure utilises eriochrome blue black RC (also called pontachrome blue black R Colour Index No. 15705) at a pH of 4,8 in a buffer solution. Beryllium gives no fluorescence and does not interfere iron, chromium, copper, nickel, and cobalt mask the fluorescence fluoride must be removed if present. The method may be adapted for the determination of aluminium in steel. 

Fairman B, and Sanz-Midel A 1995) Determination of aluminium species in natural waters. In Quevauviiler Ph, Maier EA and Griepink B, eds. Quality Assurance for Environmental Analysis, pp 216-233. Elsevier, Amsterdam,... 

Ahmad M., Narayanaswamy R., Fibre Optic Reflectance Sensor for the Determination of Aluminium (III) in Aqueous Environment, Anal. Chim. Acta 1994 291 255-260. 

Howard [27] determined dissolved aluminium in seawater by the micelle-enhanced fluorescence of its lumogallion complex. Several surfactants (to enhance fluorescence and minimise interferences), used for the determination of aluminium at very low concentrations (below 0.5 pg/1) in seawaters, were compared. The surfactants tested in preliminary studies were anionic (sodium lauryl sulfate), non-ionic (Triton X-100, Nonidet P42, NOPCO, and Tergital XD), and cationic (cetyltrimethylammonium bromide). Based on the degree of fluorescence enhancement and ease of use, Triton X-100 was selected for further study. Sample solutions (25 ml) in polyethylene bottles were mixed with acetate buffer (pH 4.7, 2 ml) lumogallion solution (0.02%, 0.3 ml) and 1,10-phenanthroline (1.0 ml to mask interferences from iron). Samples were heated to 80 °C for 1.5 h, cooled, and shaken with neat surfactant (0.15 ml) before fluorescence measurements were made. This procedure had a detection limit at the 0.02 pg/1 level. The method was independent of salinity and could therefore be used for both freshwater and seawater samples. 

Tamba, M. G., del M., Falciani, R., Lopez, T. D., and Coedo, A. G. (1994). One-step microwave digestion procedures for the determination of aluminium in steels and iron ores by inductively coupled plasma atomic emission spectrometry. Analyst 119 2081-2085. 

The flow-through sensor shown in Fig. 5.17.B, developed for the determination of aluminium in real samples (dialysis fluids and concentrates), is... 

Determination of aluminium in water for injection as a fluorescent complex Determination of stability of peptide drugs in solution Fluorescent derivatives and flow injection analysis... 

Determination of aluminium in water for injection as a fluorescent complex... 

Fluorescence measurements are useful in limit tests where the trace impurity is fluorescent or can be rendered fluorescent by chemical modification. An example is the determination of aluminium in water for use in haemodialysis solutions by formation of its salt with 8-hydroxyquinolone (Fig. 7.5) followed by quantifieation of the complex using fluorescenee speetrophotometry. The excitation wavelength is set at 392 nm and the emission is measured at 518 nm. This type of fluorescent complex can be used to determine low levels of a number of metal ions. 

Flow injection analysis has been used to determine aluminium in soil. Reis et al. [2] studied the spectrophotometric determination of aluminium in soil using merging zones and sequential addition of pulsed reagents. 

The determination of aluminium is also discussed under Multi-Cation Analysis of Soils in Sects. 2.55 (inductively coupled plasma atomic emission spectrometry) and 2.55 (emission spectrometry). 

Mitrovic et al. [7] and Kozuh et al. [8] have carried out aluminium spe-ciation studies on soil extracts. Various workers [9-11] have discussed the determination of aluminium in soils. Using isotachoelectrophoresis, Schmidt and coworkers [12] were able to differentiate aluminium(III) and aluminium species in soil leachates. 

Tecator Ltd. (1985) Determination of Aluminium in Soil by Flow Injection Analysis, Application Note ASN 78-31/85, Tecator Ltd., Bristol, UK. 

A1 NMR spectroscopy can also be used for the determination of aluminium coordination environments in solid samples. Examples of spectra from the clay minerals kaolinite and saponite, which show respectively octahedral and tetrahedral coordination of oxygen atoms around their aluminium atoms, are shown in Fig. 3.7. 

Fairman, B., SanzMedel, A., Jones, P. and Evans, E.H. (1998) Comparison of fluorimetric and inductively coupled plasma mass spectrometry detection systems for the determination of aluminium species in waters by high-performance liquid chromatography. Analyst, 123, 699-703. 

International Standard Organization. 1994. Water quality. Determination of aluminium. Spectrometric method using pyrocatechol violet. ISO 10566. International Organization for Standardization, Case Postale 56, CH-1211, Geneva 20 Switzerland. 

Morie, G. P., Sweet, T. R. Determination of aluminium and iron by solvent extraction and gas chromatography. Anal. Chim. Acta 34, 314 (1966). 

Miyazaki, M., Kaneko, H. Feasibility of gas-chromatography for ultramicro determination of aluminium in biological materials. Chem. Pharm. Bull. 18, 1933 (1970). - Anal. Abstr. 2J, 1290 (1971). 

Da-Hai Sun, J. K. Waters, T. P. Mawhinney, Microwave digestion for determination of aluminium, boron and 13 other elements in plants by inductively coupled plasma atomic emission spectrometry, J. AOAC Int., 80 (1997), 647-650. 

M. A. Zezzi Arruda, M. Gallego, M. Valcarcel, Determination of aluminium in slurry and liquid phase by flow injection analysis graphite furnace atomic absorption spectrometry, Anal. Chem., 85 (1997), 3331-3335. 

A. A. Almeida, M. I. Cardoso, L. F. C. Lima, Improved determination of aluminium in Port wine by electrothermal atomic absorption spectrometry using potassium dichromate chemical modification and end-capped graphite tubes, J. Anal. Atom. Spectrom., 12 (1997), 837-840. 

In flameless atomic absorption the analyte often tends to react with the graphite furnace or rod to form carbides. In such cases atomisation is suppressed. Release agents are used to react preferentially with the graphite releasing the analyte on atomisation. An application of this is in the determination of aluminium, barium, beryllium, silicon and tin. A large enhancement of the signal has been observed [47] when calcium (as the nitrate) is added to the analytical solutions. This has been suggested as due to a reduction in the formation of carbide in the presence of calcium. A calcium level of 1000 to 2000 mg l-1 in the solutions has been reported as the optimum in most cases. 

Solid samples may frequently require fusions. Examples of such procedures in the literature are (a) the determination of aluminium, silicon and sodium in molecular sieves using a nitrous oxide/acetylene flame following fusion (1 part to 10 of fusion mixture) with sodium carbonate, sodium... 

A method has been reported for the determination of calcium, copper, iron, magnesium, potassium, sodium and zinc in cellulose [169]. The sample (10 g) was air-dried and then ashed at 575°C until all the carbon was removed. Hydrochloric acid (5 ml of 6M) was added to the residue and evaporated to dryness twice before taking up the sample in a third aliquot, diluting to 100 ml and aspiration into an air /acetylene flame. It is likely that volatile elements such as cadmium may be lost at such an elevated ashing temperature and temperatures below 500°C may be preferable. Alternatively wet ashing with nitric acid has been proposed for the determination of aluminium, cadmium, potassium and zinc in pressed boards [170] or sodium in gypsum glass board [171]. For the determination of lead in confection wrappers, the sample may be treated with concentrated nitric acid at 70—80°C and diluted for flame analysis [172]. In the full method, the wrapper was wiped clean with a damp tissue, cut up to 0.5 X 0.5 mm pieces and dried at 110°C (for paper, for plastic 80°C) for 1 h. The sample (0.5 g) was heated with concentrated nitric acid (1ml) at... 

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