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Jiang J.-Q.,Glasgow Caledonian University | Durai H.B.P.,Glasgow Caledonian University | Winzenbacher R.,Zweckverband Landeswasserversorgung | Petri M.,Zweckverband Bodensee Wasserversorgung | Seitz W.,Zweckverband Landeswasserversorgung
Desalination and Water Treatment | Year: 2015

Abstract: The present study aims to investigate the efficiency of on-site produced ferrate(VI) for drinking water treatment as well as for the removal of micro pollutants. The study examined and validated the laboratory electrochemical production of ferrate(VI) and tested water treatment efficiency of the resulting ferrate(VI) in comparison with that of FeClSO4 and poly-aluminium chloride (PACl). The performance of water treatment was compared by the removal efficiency of turbidity, dissolved organic carbon, microbial count and trace organic micro pollutants. Major observations were that 0.5 mg/L of ferrate(VI) as Fe was sufficient to remove most of the contaminants and achieve complete disinfection irrespective of the original microbial counts. Ferrate(VI) has considerable oxidation potential to degrade commonly occurring trace organic micropollutants (other than melamine) in the Danube River water. In contrast, FeClSO4 or PACl cannot remove any trace micro pollutants. © 2015 Balaban Desalination Publications. All rights reserved. Source

The coupling of liquid and gas chromatography with high resolution mass spectrometry has created new possibilities for the detection and identification of micropollutants in ground-, surface and drinking water. A new concept of screening has been established in the water analytical chemistry in the last years: target-, suspected- und non-target-screening. The screening technology offers new possibilities for the detection of new micropollutants, metabolites and transformation products in water, even if the new technology could not come up to all expectations. An intensified optimization and harmonization of the methods for detection and evaluation and the extension of existing mass spectra database will improve the comparability of the results. Source

Petri M.,Zweckverband Bodensee Wasserversorgung | Jiang J.-Q.,Glasgow Caledonian University | Maier M.,University of Surrey
Water Science and Technology: Water Supply | Year: 2010

Much of the water supply industry has implemented online monitoring and warning systems for chemical or biological contaminations. When a contamination is detected, further investigations are necessary to confirm or to cancel the initial alarm. The proficiency of a non-target screening approach with solid phase extraction and GCMS in full-scan mode was examined. A selection of pesticides and industry chemicals was used for proficiency testing in extracts of raw and drinking water from Lake Constance. All total ion chromatograms (TIC) of extracted water samples showed a significant chemical background that have an adverse effect on compound identification. The TIC was evaluated with a two-dimensional search algorithm considering mass spectra similarity and retention index for identification, which was used an additional identification criteria to increase the confidence in identification. At a spiking level of 0.50mg/l, up to 70% of the pollutants were unambiguously assignable. The sample pre-treatment was kept as simple as possible to reduce analysing time. A solid-phase extraction with extraction disks at flow rates up to 100 ml/min without any precedent filtration step reduces the sample pre-treatment time for a 1 l-sample below one hour. The recovery rates for most of the examined pollutants were above 60%. © IWA Publishing 2010. Source

Gilfedder B.S.,TU Braunschweig | Petri M.,Zweckverband Bodensee Wasserversorgung | Wessels M.,Institute For Seenforschung Der Landesanstalt For Umwelt | Biester H.,TU Braunschweig
Geochimica et Cosmochimica Acta | Year: 2011

Bromine was historically termed a cyclic salt in terrestrial freshwater environments due to its perceived conservative cycling between the oceans and the continents. This basic assumption has been challenged recently, with evidence that bromine is involved in dynamic chemical cycles in soils and freshwaters. We present here a study on dissolved bromine species (bromide, organically bound bromine, DOBr) concentrations and fluxes as well as sediment trap bromine levels and fluxes in Lake Constance, a large lake in southern Germany. Water samples were obtained from all major and some minor inflows and outflows over one year, where-after dissolved bromine species were measured by a combination of ICP-MS and ion chromatography coupled to an ICP-MS (IC-ICP-MS). Sediment traps were deployed at two locations for two years with Br, Ti and Zr levels being measured by μ-XRF.190tyr -1 of total dissolved bromine (TDBr) was delivered to the lake via 14 rivers and precipitation, with the rivers Alpenrhein (84tTDBryr -1) and the Schussen (50tTDBryr -1) providing the largest sources. The estimated particulate bromine flux contributed an extra 24-26tBryr -1. In comparison, only 40tTDBryr -1 was deposited to the lake's catchment by precipitation, and thus ~80% of the riverine TDBr flux came from soils and rocks. Bromide was the dominant species accounting for, on average, 78% of TDBr concentrations and 93% of TDBr flux to the lake. Despite some high concentrations in the smaller lowland rivers, DOBr was only a minor component of the total riverine bromine flux (~12tyr -1, 7%), most of which came from the rivers Schussen, Bregenzer Ach and Argen. In contrast, most of the bromine in the sediment traps was bound to organic matter, and showed a clear seasonal pattern in concentrations, with a maximum in winter and minimum in summer. The summer minimum is thought to be due to dilution of a high Br autochthonous component by low bromine mineral and organic material from the catchment, which is supported by Ti, Zr and Br/C org data. In the lake bromine was irreversibly lost to the sediments, with best flux estimates based on mass-balance and sediment trap data of +50-90μgBrm -2d -1. Overall, it appears that bromine is not simply a cyclic salt in the case of Lake Constance, with a clear geological component and dynamic lacustrine biogeochemistry. © 2011 Elsevier Ltd. Source

Petri M.,Zweckverband Bodensee Wasserversorgung | Petri M.,Glasgow Caledonian University | Jiang J.-Q.,Glasgow Caledonian University | Maier M.,Stadtwerke Karlsruhe
Journal of Applied Spectroscopy | Year: 2013

The accuracy and reliability of semi-quantitative inductively coupled plasma mass spectrometry (ICP-MS) were evaluated through two certified reference materials and real water samples from the Lake Constance Water Supply. Results for the real water samples measured by semi-quantitative ICP-MS were compared with those analyzed by different quantitative methods. With semi-quantitative ICP-MS it is possible to determine elements not present in the calibration standard. The concentrations of non-calibrated elements might be questionable, but can give a reliable hint for the presence or absence of elements in the sample. The results demonstrate that semi-quantitative ICP-MS is a reliable tool to analyze aqueous samples in emergency situations. © 2013 Springer Science+Business Media New York. Source

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