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The effects of organic cleaning agents (totally three) and degradation products from solid technical adsorbents (two) on the sorption of Eu on cement and TiO2 were measured with variation of concentration (0.001-10% of the water phase for the cleaning agents, alkaline degradation products corresponding to 0.03-8 mM DOC for the adsorbents) and reaction time (up to 420 d). The effects of the cleaning agents Industrikombi and Prefect Citron were minor. The degradation of the ion exchanger (metaacrylic polymer) had no significant effect on the Eu-sorption. The other adsorbent (filter aid, inert fibre; acrylonitrile polymer) was rapidly degrading at high pH, and the degradation products had a significant reducing effect on the sorption of Eu at added DOC-levels in the mM-range. This category of adsorbent materials should not be incorporated in a cement waste matrix or be stored in a cementitious environment together with radionuclides., QC 20141212

The effects of organic cement additives (totally 7) on the sorption of Eu on cement and TiO2 were measured with variation of the concentration of the additive (0.001-10% of the water phase) and reaction time (up to 420 d). There was a significant reduction of the sorption of Eu on cement as well as on TiO2 after 24 h of exposure time in the presence of additives at levels that would be obtained in a cement/water system if the total load of the additive in the cement (up to 3%) would be released into the water phase. Sorption increased with time and would be expected to reach constant levels after 100-200 d. Storage of the additives at 60 and 120°C, pH 12.5, for up to 110 d (in order to degrade them) did not lead to significantly altered sorption behaviour., QC 20141211

Electroremediation makes treatment of contaminated clay soils possible. The external electrical field causes several transport processes and changes in soil chemistry. This study concerns the leachability and transport of calcium, magnesium, copper, zinc, lead, nickel manganese, chromium, and iron during treatment with an electric field of soil from a chlor-alkali factory. As expected, most elements were removed from the acidic part of the soil and accumulated in the zone where pH changed from acidic to alkaline. However, acidic leaching of the soil in this zone did not mobilize the elements. Lead formed both an anionic complex which electromigration transported toward the anode as well as a cationic lead fraction which moved toward the cathode. The anionic complex could be lead sulfate. Lead from both fractions was strongly attached to the soil after treatment. The low availability of metals and macroelements after electrokinetic remediation could make electroremediation, excavation, and deposition of the accumulation zone an alternative for the treatment of contaminated soils.

A 30 V direct electric field was applied to a contaminated soil from a chlor-alkali plant for 182 days. The principal soil contaminats were mercury, polchlorinated dibenzofurans, and lead. When chloride was added to the soil, mercury moved towards the cathode, showing that anionic mercury chloride complexes did not dominate. When iodide was added to the soil solution, mercury moved towards the anode, illustrating the predominance of an anionic mercury iodide complex. The iodide mobilised mercury from the soil and transported it rapidly into the anode solution, so that mercury was removed from the soil. When the experiment was continued, mercury returned to a cationic form and electromigration transported the mercury back into the soil. This was probably due to the lower iodide concntrations that may result from the oxidation of iodide to iodine near the anode. Sequential extraction showed that mercury was strongly bound to the soil, both before and after the electrokinetic treatment. The heavy metals were found in the 'acidic and oxidising', and the residual fraction of the leaching procedure. Mercury was more available after the treatment with iodide.

Cellulose powder and softwood sawdust were subjected to alkaline degradation under conditions representative of a cementitious environment for periods of 7 and 3 years, respectively. During the first 3 years, sampling was frequent, and data on the degradation of cellulose and production of isosaccharinic acid was used for establishing long-term prediction models. Samples after an additional period of 4 years were compared to the predicted values. The total rate of degradation was measured as the increase in total organic carbon (TOC) in corresponding solutions. A previously published theoretical model of degradation kinetics gave a good approximation of the present experimental data. Peeling-off, stopping, and alkaline hydrolysis reaction rate constants were obtained as model parameters, and the results suggested that the transformation of the glucose end group is the rate-limiting step in the cellulose peeling-off reaction and also determines the pH dependence of that reaction. After 3 years, isosaccharinic (ISA) acid represented 70-85% of all degradation products as quantified by capillary zone electrophoresis. The long-term prediction model indicated that all of the cellulose would be degraded after only 150-550 years. The control sampling after 7 years points toward a lower degradation of cellulose and production of ISA than predicted by the model, reflecting either a degradation of ISA that was faster than the production or a termination of the ISA production.

A systematic study of the standard SPICE model of the diode in the case of simulations of power diodes in power electronic applications shows the limits of accuracy with respect to experiments. Therefore, the interest in such a model in power electronic applications is comparable to the high-low resistance model., QC 20100810

The River Vormbacken, which receives treated acid mine drainage (AMD) from the Kristineberg complex sulphide mine, northern Sweden, flows through various wetlands. Water quality data from 11 years of monitoring at six sampling stations were analysed. It was found that chemistry data alone cannot determine the impact and functioning of wetlands; more sophisticated analysis including historical water flows may provide more insight., The River Vormbacken, which receives treated acid mine drainage (AMD) from the Kristineberg complex sulphide mine, northern Sweden, flows through various wetlands. Water quality data from 11 years of monitoring at six sampling stations were analysed. It was found that chemistry data alone cannot determine the impact and functioning of wetlands; more sophisticated analysis including historical water flows may provide more insight.

The composition of water leachable organics in municipal solid waste incineration (MSWI) residues is not well known. Therefore the utilisation of ashes is restricted due to the concern about their long-term environmental impact. Previous studies have focused on some highly toxic organic compounds present only in trace amounts. It is also important to know the composition of the bulk organic matter since dissolved organic carbon can alter the leachability of metals. In order to characterise water leachable organic matter in incineration residues a fractionation procedure using polymeric adsorbents was successfully developed and applied. The technique uses XAD-8 and XAD-4 resins in tandem and has been implemented on bottom ash samples from two incineration plants in Sweden in order to characterise the bulk organic matter.

The applicability of a recently developed capillary zone electrophoretic (CZE) method for the determination of low molecular weight (LMW) organic acids in water was tested on five types of environmental samples (rainwater, water extract from peat, and soil water from two polluted sites). A full baseline resolved separation of fourteen commonly found LMW carboxylic acids in natural waters (malonic, oxalic, fumaric, maleic, formic, succinic, tartaric, glutaric, adipic, acetic, propionic, butyric, valeric and citric acids), was achieved within eight minutes. The limits of detection (2 x noise) were in the ranges 90-200 mug/l and 0.5 - 5 mug/l for hydrodynamic and electrokinetic injection, respectively. Two different CZE systems, a Waters Quanta 4000 and a Hewlett Packard HP (CE)-C-3D system, were used and their performance compared.