Atomic absorption spectroscopy particulate analysis

Pretreatment of the collected particulate matter may be required for chemical analysis. Pretreatment generally involves extraction of the particulate matter into a liquid. The solution may be further treated to transform the material into a form suitable for analysis. Trace metals may be determined by atomic absorption spectroscopy (AA), emission spectroscopy, polarogra-phy, and anodic stripping voltammetry. Analysis of anions is possible by colorimetric techniques and ion chromatography. Sulfate (S04 ), sulfite (SO-, ), nitrate (NO3 ), chloride Cl ), and fluoride (F ) may be determined by ion chromatography (15). 

A number of instrumental methods have been used to determine ppb levels of cobalt in water (4,5,6), biological tissues (7,8), and air particulates (9, 10). Kinetic methods are capable of measuring sub-parts-per-billion (11,12). Potentially any of these techniques could be used in the analysis of petroleum, but only neutron activation analysis (I, 3) and atomic absorption spectroscopy (13,14) have been applied to any appreciable extent. Flame and heated vaporization atomic absorption techniques were selected for more detailed study by the Project because atomic absorption is sensitive, subject to relatively few interferences, and is rather generally available. 

Samples of airborne particulates preferably are collected on glass fiber or membrane filters. The analytical method of choice is atomic absorption spectroscopy after acid digestion of the filter and appropriate dilution. However, other methods such as spectrography, polarography, spectrophotometry, neutron activation analysis, and anodic stripping voltammetry are also used. 

His laboratory is concerned with the analysis of a wide range of materials which include a variety of biological specimens, mineral samples, air particulate matter, and water samples. The information obtained is used to evaluate various individual and environmental problems. Two of the techniques which have been used for water analysis are atomic absorption (J, 4) and flame emission (2) spectroscopy, and a study of factors aflFecting these methods is described here. The samples came from a number of sources which included well water and city water. Consequently, the concentration ranges of some of the elements were quite wide. Five determinations were made daily on both the samples and standards for each element over a period of several months to provide suflBcient data for an adequate evaluation of precision. At present, ten elements (Na, K, Ca, Mg, Zn, Pb, Mn, Cu, Fe, and Ni) are being determined quantitatively. 

---