Aluminium, determination

F. R. Amorim, C. Bof, M. B. Franco, J. B. B. Silva and C. C. Nascentes, Comparative study of conventional and multivariate methods for aluminium determination in soft drinks by graphite furnace atomic absorption spectrometry, Microchem. J., 82(2), 2006, 168-173. 

N. Jalbani, T. G. Kazi, M. K. Jamali, M. B. Arain, H. I. Afridi, S. T. Sheerazi and R. Ansari, Application of fractional factorial design and Doehlert matrix in the optimisation of experimental variables associated with the ultrasonic-assisted acid digestion of chocolate samples for aluminium determination by atomic absorption spectrometry, J. AO AC Int., 90(6), 2007, 1682-1688. 

For some elements, especially those which tend to form thermally stable oxides, fuel-to-oxidant ratio may have a dramatic effect upon atomic absorbance signal. Figure 4, for example, illustrates the effect of increasing fuel flow upon aluminium determination. 

Tiron reacts at this pH value only with aluminium and iron(III), hence this aluminium determination method is very selective. The only disadvantage is the comparatively low extinction coefficient of the resulting complex at 310 nm being e = 6000 L/(mol cm). 

Al, Si Digestion with concentrated sulphuric acid-chromic acid in current of oxygen. Silicon determined volumetrically as Na2SiF6. Aluminium determined by titrimetric EDTA method. 

Al, Si, P Digestion with diethyl ether-concentrated sulphuric acid-potassium persulphate. Silicon determined gravimetrically. Aluminium determined by titrimetric EDTA method. Phosphorus determined by spectrophotometric molybdenum blue method. 

Future trends in trace element analysis will put even greater pressure on the need to provide unbiased determinations. Increasing interest in the role of trace elements in health and disease will provide the stimulus for the better provision of quantitative determinations on which important decisions are made (Centers for Disease Control, 1991 Moukarzel et al., 1992). Increased public awareness and legislation are likely to bring about substantial reductions in the currently acceptable levels of occupational and environmental exposure to some non-essential elements such as lead, cadmium and aluminium. Determinations that are made as part of the assessment of such exposure will need to be both carefully validated and reproducible over many years or decades (Braithwaite and Brown, 1988 Brown, 1991), which will have a serious impact on laboratory costs. However, reproducible trace element determination with a low bias in biological fluids represents the cornerstone of any proper understanding of the role of trace elements in human health and disease. 

Leung, F.Y. and Henderson, A.R. (1983) Assessment of quality control sera suitable for aluminium determination by atomic absorption spectrometry. In Brown, S.S. and Savory, J. (Eds.) Chemical Toxicology and Clinical Chemistry of Metals, Academic Press, London, p. 69. 

As with many elements, total aluminium determinations are of limited value for environmental toxicological purposes, owing to the different toxicology/ bioavailability patterns related to the various A1 species, which justifies A1 speciation measurements. 

A.2.2 Aluminium determination with the graphite tube technique (Furnace method)... 

This method describes a procedure for the determination of 20 to 250 ppm of aluminium and more than 1 ppm of vanadium in polymer samples. Tin and zinc and large amount of cobalt, nickel and lead interfere with the aluminium determination. These interfering metals can be removed by a suitable modification of the basic procedure. 

BS ISO 21687 2007. Carbonaceous materials used in the production of aluminium, determination of density by gas pyknometry (volumetric) using helium as the analysis gas. Solid materials. 

Recent Uses of 14 MeVN.A.A. Espanol and Marafuschi report the use of 14 MeV n.a.a. for the determination of Al/O ratios in sintered alumina powders using the usual 0(n,p) N reaction for oxygen and the Al(n,p) Mg reaction for aluminium determination interferences from F and B are discussed. The analysis of oxygen in electrolytic baths is particularly complicated by the F(n,a) N interference due to the presence of NasAlFs, and a correction is necessary based upon the F also induced in the sample by the F(n,2n) F reaction. The interference can also be eliminated by using a lower-energy neutron flux (say, 12 MeV) the F(n,a) N cross-section is much reduced, whereas the 0(n,p) N cross-section is at a maximum. The interference of F is quite serious Morgan and Ehmann report that 0.1 % F gives a response equivalent to an apparent O content of 0.0415% in meteorites. 

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