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Pollutants in laboratory waste waters
Červenka, Jiří ; Zmrzlý, Martin (referee) ; Sponar, Jan (advisor)
Mercury is a very consequential pollutant. It´s contained in all components of environment. Analysis of mercury is very demanding. Since mercury is ranked among dangerous chemicals, its quantity is limited and checked not only in environment. The aim of this thesis was to determine concentration of mercury in water from labs and in influent and effluent water from neutralization station of Brno university of Technology, Faculty of Chemistry. Water from neutralization is also mixed with sewage. Advanced mercury spectrometer AMA 254 was used or analysis. Results confirmed, that water flows out from lab to neutralization with relatively high concentration of mercury, highly exceeding limits of drainline. Water from neutralizing station also doesn´t show so high concentration of mercury, because it is mixed with waters from other labs and pH of water is amended. Special waste bottles for liquid waste with risk elements and dangerous compounds are available; from results can be decided, that not everybody follows the rules and some people might pour the waste right in to the sink. Resolution could have been safer acquisitions in labs. Students, who manipulate with dangerous chemicals should be alive to risk, which threatens with pouring into the sink, contamination and dangerous for all components of environment.
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Pollutants in laboratory waste waters
Červenka, Jiří ; Zmrzlý, Martin (referee) ; Sponar, Jan (advisor)
Mercury is a very consequential pollutant. It´s contained in all components of environment. Analysis of mercury is very demanding. Since mercury is ranked among dangerous chemicals, its quantity is limited and checked not only in environment. The aim of this thesis was to determine concentration of mercury in water from labs and in influent and effluent water from neutralization station of Brno university of Technology, Faculty of Chemistry. Water from neutralization is also mixed with sewage. Advanced mercury spectrometer AMA 254 was used or analysis. Results confirmed, that water flows out from lab to neutralization with relatively high concentration of mercury, highly exceeding limits of drainline. Water from neutralizing station also doesn´t show so high concentration of mercury, because it is mixed with waters from other labs and pH of water is amended. Special waste bottles for liquid waste with risk elements and dangerous compounds are available; from results can be decided, that not everybody follows the rules and some people might pour the waste right in to the sink. Resolution could have been safer acquisitions in labs. Students, who manipulate with dangerous chemicals should be alive to risk, which threatens with pouring into the sink, contamination and dangerous for all components of environment.
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A comparative study of the total mercury determination in highly contaminated soils by AAS and RNAA methods
Sysalová, J. ; Kučera, Jan ; Zvěřina, O.
High total mercury (T-Hg) contents in soils, up to 25 mg kg−1, were determined by two independent methods: a one-purpose atomic absorption spectrometer AMA-254 (Advanced Mercury Analyser) with direct solid sampling, and radiochemical neutron activation analysis (RNAA), using sample masses of 10 mg to 25 mg and about 150 mg, respectively. An excellent agreement between results of both methods was obtained. For quality control (QC) purposes, NIST SRM 2711 Montana Soil and NIST SRM 2711a were analysed by both methods using the above sample masses. The results obtained were compared with the NIST certified values within the uncertainty margins, thus proving the accuracy of the procedures employed. It has been found that the cryogenic grinding used provided sufficiently representative and homogeneous samples. A test in which HgS was analysed by RNAA showed that even mercury present in sulfide form would be fully recovered using the procedures employed. For contents of T-Hg above the upper limit of the AMA-254 working range (500 ng), samples were firstly diluted with sea sand in the ratio 1:10 and homogenised well to get RSD below 5%. The dilution procedure was verified using the certified reference material ERM-CC580 Estuarine Sediment.
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