A Simplified Analytical Procedure for the Determination of Organically Bound Halogens in Salt‐containing Water Samples

A method was developed for the determination of organic halogens in water samples with the aim of minimizing matrix effects and simplifying the sample preparation technique commonly used. The method is based on the adsorption of organic halogens in modified hydrophilic divinylbenzene polymer columns and their elution with methanol. The adsorbent used enables rapid adsorption and desorption due to comparatively high operating flow rates and minimized solvent amounts. Furthermore, no additional reconcentration steps are needed. The methanol extract obtained is combusted with a standard EOX (extractable organic halogen) analyzer and the concentration of organically bound halogens is determined by microcoulometric analysis. The matrix effects are considerably reduced compared to the standard procedure (EN 1485) commonly used. A detection limit of 13 μg/L was established.     

Anwendung eines neuen Feldanalysenverfahrens zur Untersuchung der Stabilität von Arsen und seinen anorganischen Spezies in aquatischen Systemen

Using of a New Field Analysis Method to Investigate the Stability of Arsenic and its Inorganic Species in Aquatic Systems The stability of arsenic species in aquatic systems is limited by the possibilities of chemical and biochemical reactions. Redox reactions and bioalkylation lead to changes of the species ratios. In this work, the stability of As(III) and As(V) was examined at storage of distilled, de-ionized, and drinking water at different conditions (refrigerator/room temperature; daylight/darkness) and additions (sulfuric acid; ascorbic acid). The determination of these species was carried out by a modified spectrophotometric method, suitable for laboratory analysis as well as for field analysis. The results show that chemical oxidation and biochemical reduction can occur. Sulfuric acid is favourable for the stabilization of total arsenic and of the inorganic species.     

Application of UV Spectrophotometry to the Study of Treated Wastewater Discharges in Rivers

Ultra-violet Spectrophotometry has been used for qualitative and quantitative analysis of water and wastewater in conjunction with appropriate signals and a deconvolution method. Application of this procedure with the use of a portable UV spectrophotometer was carried out to study treated wastewater discharge into a river. The data obtained were used to estimate dilution factors of polluted waters at different points of sampling. This simple and rapid methodology can be easily transposed with any PC-controlled UV spectrophotometer including a multicomponent routine.