Untersuchung der Anwendungsmöglichkeiten von einigen komplexbildenden Ionenaustauschern zur Kupferabtrennung aus natürlichen Wässern und Abwässern

Application of Some Complexing Ion Exchangers for Copper Recovery from Natural Water and Wastewater The rational use of water resources is one of the urgent environmental control problems. These problems can be solved by the treatment of sewage. Removal of different non‐ferrous heavy metal ions from wastewater is of great importance. Besides, the selective complexing ion exchangers are of interest because of their good sorption properties. The present paper is devoted to the study of some complexing resins for copper recovery from natural water and sewage. The following carboxylic resins were studied: the cation exchangers KB‐2T, KB‐4 and the amphoteric ion exchangers ANKB 35, AMF‐2T, and AMF‐2S (manufacturer – “TOKEM” company, Kemerovo, Russia). The exchangers investigated differed from each other both by their functional groups and by their matrix physical structures. The copper recovery from CuCl₂‐, CuSO₄‐, and Cu(NO₃)₂‐solutions was studied in batch‐experiments (in presence of NaCl, Na₂SO₄, and NaNO₃). The initial copper concentration in the solutions was 0.0002...0.008 mol/L; pH values were 1.0...5.0. After equilibrium (24 h) the resins were separated from the solution. The copper concentration in the solutions after the sorption was determined by the photometrical method with pyridylazoresorcin (λ = 500 nm). On the basis of the experimental data distribution ratio, the separation factors, equilibrium constants, and stability constants of copper complexes in the exchanger phase were calculated. It was found out in this work that the amphoteric ion exchanger AMF‐2T of macroreticular structure is the most effective for the copper sorption from sewage.     

Möglichkeiten der Nachreinigung von Abwässern aus der Kunstlederproduktion mit Hilfe von Algen

In the production of a special artificial leather (BAREX) in the CSSR wastewaters containing dimethylformamide (DMF) and dimethylamine (DMA) are produced. Investigations have shown that cultures of algae (Scenedesmus quadricauda) are able to use the two substances as a nitrogen nutrient source after a time of adaptation. In the course of the reactions of decomposition the pH-value plays an important part, since at increased values ammonia is released, which has a temporarily inhibitory effect on the production of algae masses and daughter cells. This detrimental effect can be considerably reduced by aeration with carbondioxide containing (3%) air. Since the production of algal biomass is restricted by a phosphorus deficiency, too, a combined treatment with municipal sewage is very advantageous, according to the results from investigations.     

Pestizidbestimmung im Wasser – gegenwärtige Möglichkeiten und künftige Entwicklungen

Summary: In the drinking-water regulation of the Federal Republic of Germany limit values in the range of 0.1 μg/l are established for pesticides. Identification and quantitative determination of pesticides in this concentration range require a very high expenditure concerning analysis, devices and equipment, analytical methods having been available so far only on a limited scale. The sum limit value of 0.5 μg/l pesticides may create special difficulties. In general, in view of the approx. 300 possible substances first of all a screening has to be proposed concerning the exceeding of limit values based on knowledge from the catchment area and its potential loading as the first step of investigation. Suitable methods of determination are partly available in gas chromatography and high-pressure liquid chromatography. Promising in the future development are the biochemical methods of enzyme inhibition (cholinesterase) and of immunoassay with radioactive and enzyme labelling. Nevertheless, for the foreseeable future standard methods will be available only for approx. Two thirds of the total of 300 substances, so that discussing the effectiveness of the limit values should be carried on.     

Möglichkeiten der Nachreinigung von Abwässern aus der Kunstlederproduktion mit Hilfe von Algen,Teil 2

The attempt was made to use the alga Scenedesmus quadricauda for the purification of wastewaters from the production of artificial leather. The dimethylamine contained in these wastewaters is continuously decomposed and the remaining nitrogen-containing residuals are used as a nutrient source for the production of algal biomass. In continuous experiments with original wastewaters, dimethylamine and its metabolites showed a pronounced inhibiting effect. In practice, a longer retention time in the reactors as well as a sufficient share of municipal wastewater are required in order to avoid a limiting of growth due to a phosphorus deficiency. The second part of this paper is concluded by information about other investigations performed by us on the purification of artificial leather wastewaters with the aid of the biological nitrogen elimination under specific conditions with a successful denitrification of up to 95%.     

Ökotechnologischer Einsatz von höheren Wasserpflanzen in stehenden und gestauten Gewässern — Möglichkeiten,Grenzen

Species of macrophytes which are suitable for the biogenic aeration of the hypolimnion by macrophytes must reach positive balances of the net primary production at a high development of populations also at low light intensities and temperatures (winter). Elodea canadensis, Juncus bulbosus and Littorella uniflora from suitable sites were exposed after holding at different water depths, and the biomass development was investigated in relation to the radiation intensity. Parallel to that, the net primary production was determined in dependence on the light intensity in the bottle experiment by air-conditioned laboratory experiments (oxygen method). Elodea canadensis has been found to be suitable for the ecotechnological application to more eutrophic waters with neutral pH, especially because of the low light compensation point of the net primary production. Colonization with Juncus bulbosus, however, seems to be possible only in the acidophilic range (pH<7), whereas Littorella uniflora is not suitable for floating vegetation covers because of the higher light compensation point for a hypolimnetic colonization and the linkage to the substrate.     

Pattern-Recognition-Verfahren in der Umweltanalytik und Ökotoxikologie: Methodische Grundlagen

Modern methods of analyses of environment yield multivariate data sets of measured objects which are used as the basis of the evaluation and interpretation of substances, differentiated effects, but also of samples or processes. The integrated evaluation and assessment of such multivariate data requires the application of mathematical-statistical methods, the method of pattern recognition being particularly suitable. Pattern recognition program systems constitute a compilation of different methods, as e.g. the multivariate linear regression, classification methods (discriminant analysis, multivariate variance analysis), cluster algorithms, multidimensional scaling, factorial analysis. A few possibilities of such pattern comparisons and identifications are represented by the example of gas chromatography and of the structure/effect analysis for the mutagenity to be expected of 117 substances.