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Separation of microplastics from sewage sludge using heavy liquids
Pospíchalová, Eliška ; Innemanová, Petra (advisor) ; Cajthaml, Tomáš (referee)
This bachelor thesis is focused on microplastics in sewage sludge. Microplastics are currently often discussed topic, but their occurrence in sewage sludge isn't still sufficiently researched. The main source of microplastics in sewage sludge is waste water. Microplastics are accumulating in sewage sludge during wastewater treatment and enter terrestrial ecosystems with multiple times higher concentration in comparison to freshwaters as a result of their use in agriculture or in restoration. In the year of 2017 sewage sludge was in Czech Republic further processed by direct land application within agriculture and restoration of 42 %, compostation of 34 %, other uses of 14 %, landfilling of 7 % and incineration of 3 %. The use of sewage sludge in agriculture demonstrates significance of microplastics issue. The tested samples were sampled from five anonymous wastewater treatment plants in Czech Republic. The samples were investigated for applicability of methodology of separation microplastics with oxidation of natural organic matter by Fe2+ + 30 % H2O2 and flotation in saline solution of 5 M NaCl. Following identification of microplastics was carried out in optical microscope with magnification of 40x. For precise optical detection of microplastics the samples were dyed with rose bengal. The...
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Microplastics in Drinking Water
Čermáková, Lenka ; Novotná, Kateřina ; Peer, Petra ; Janda, V. ; Pivokonský, Martin
The research was focused on microplastics occurring in water sources and in drinking water. Recently, the topic of microplastics in water is very up to date. However, most of the studies are focused on quantification of microplastics in sea water, sediments or surface waters, which are not a source of raw water for drinking water treatment, and at the same time the most of studies deal with the analysis of particles in the size range of 0.3 - 5 mm. The subject of the present study was to quantify microplastics from 0.2 μm in raw and treated water from three unnamed water treatment plants in the Czech Republic and to determine their size distribution, shape and material composition. It has been found that the number of microplastics ranged from 1414-7006 L-1 particles in raw water and 305-921 L-1 particles in treated water. Microplastics smaller than 10 μm were the most plentiful in both raw and treated water samples. Fragments clearly prevailed at two of the water treatment plants and fibres together with fragments predominated at one case.
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Biodegradation of lightweight polyurethanes in soil and subsequent analysis of their degradation products
Pražanová, Kateřina ; Innemanová, Petra (advisor) ; Cajthaml, Tomáš (referee)
According to the Waste Framework Directie 2008/98/ES and the Czech law on waste 185/2001 Sb., waste preienton is the main priority in waste management. Using biodegradable plastcs seems to represent a suitable approach in fulflling the strategy. The subject of this diploma thesis is biodegradable lightweight polyurethanes (PURs), which might represent suitable materials for repellent fences in agricultural landscapes. Biodegradaton processes are assumed to begin in the agricultural soil afer their lifetme. The biodegradability of new lightweight PURs (BIO 8-10), presented as material mineralizaton, was tested in agricultural soil under laboratory conditons according to the ASTM Internatonal standard method D5988-03. Afer the nine-month experiment the material with the highest biodegradability (BIO 10) containing starch (28 wt. %) was mineralized to 42.0 ± 4.2 %. Cellulose (the positie control) was completely mineralized; thus, the ialidity criterion (positie control mineralizaton > 70 %) was accomplished. Afer the biodegradability test, degradaton products (residual PURs) were separated from the soil by a two-step method using fuidisaton and fotaton, according to a modifed procedure described in Nuelle et al. (2014). The procedure enabled a subsequent analysis of PUR residues with Fourier transform...
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Detection of microplastics in the environment
Havlíčková, Lucie ; Cajthaml, Tomáš (advisor) ; Innemanová, Petra (referee)
This bachelor thesis is focused on microplastics as small fragments of plastics which represent a burden for the environment and can be probably dangerous for living organisms including mankind. Serious health consequences caused by a long term exposition of the microplastics to organisms have been demonstrated in the recent years. It has been proven that the level of harm increases with ability to adsorb toxic substances on their surface. Primarily, it is necessary to eliminate entrance of these microparticles into the ecosystem and therefore this thesis describes routes of microplastic inputs into the environment. The microplastics occur in all levels of the environment, that represent various environmental matrices with different conditions, that must be considered for successful separation and subsequent analysis of samples. This thesis provides summarization of currently used analytical methods including their advantages and comparisons. The most frequently used techniques of separation are based on the principle of density flotation. Further identification of fragments is performed using microscopy, spectroscopy or gas chromatography. This work describes principles of the individual techniques of detection including also particular cases of analyses. The subject of this thesis is also the...
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The development of a TGA-MS based method for determination of microplastics in soils
Šilhánková, Lenka ; Mravcová, Ludmila (referee) ; Kučerík, Jiří (advisor)
Plasty, pronikající do životního prostředí ať už neúmyslně či záměrně, mohou být fragmentovány za vzniku částic v řádu mikrometrů (tzv. mikroplastů) a znečišťovat tak půdní systémy. Doposud vyvinuté analýzy pro stanovení mikroplastů v půdách jsou především zaměřeny na kvalitativní stanovení, nicméně i jejich provedení se zatím stále potýká s různými úskalími. Navíc, téměř všechny tyto analýzy vyžadují časově náročnou předúpravu vzorku. V této studii jsme se zaměřili na vývoj nové analytické metody pro kvantitativní stanovení mikroplastů polyvinylchloridu (PVC) a polystyrenu (PS) v půdách bez předchozí úpravy vzorku pomocí termogravimetrické analýzy spojené s hmotnostní spektrometrií (TGA-MS). Pro analýzu byly použity vzorky modelové půdy s nízkým obsahem organického uhlíku, které byly spikovány na výslednou koncentraci 0,23–7 hm% PVC či PS. Vzorky byly pyrolyzovány s teplotním krokem 5 K min–1 až na teplotu 1000 °C. Pyrolýzní plynné produkty byly následně analyzovány s využitím hmotnostního spektrometru. Získaná data byla normalizována pomocí externího standardu (šťavelan vápenatý). Limity detekce se pohybovaly v rozmezí 0,08–5,3 hm% pro PVC a 0,005–0,7 hm% pro PS v závislosti na zvoleném m/z. Limity kvantifikace pak byly 0,3–17,7 hm% pro PVC a 0,002–2,2 hm% pro PS. Výsledky dokazují, že spojení TGA-MS může být konkurující semikvantitativní metodou pro stanovení mikro-PVC a mikro-PS v půdě s nízkým obsahem organického uhlíku.
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Biodegradability assessment of new types of lightweight polyurethanes
Tošovská, Kateřina ; Innemanová, Petra (advisor) ; Beneš, Hynek (referee)
The subject of the bachelor thesis is biological degradation (biodegradation) of new types of lightweight polyurethanes which were synthesized for an agriculture application. The theoretical part summarises the utilization and biodegradation principles of polyurethanes and it outlines standardised methods for quantification of biodegradability potential. The biodegradability potential of the new materials was tested respirometrically according to the standard D 5988 under laboratory conditions for 150 days. Cellulose (the positive control) was mineralised of 30,25±2,28 %. The best biodegradable material (PUR-B) was mineralised of 9,73±1,95 %. According to the procedure described in the standard D 5988 our results were undervalued. Consequently absorbed CO2 released from biodegradeble materials was stabilised by reaction with BaCl2. The reaciton is needed to interpret the results correctly. A screening method for a quick test of biodegradability was designed. It included biodegradation by bacterial inoculum in mineral medium. The availability of materials for microbial degradation was meassured as a time-dependent function of optical density. The non-biodegradable residual particles of plastics represent a potential risk for the environment. The issue of microplastics and their quantification was...
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