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Removal of microplastics from water
Skalníková, Andrea ; Pivokonský, Martin (advisor) ; Čermáková, Lenka (referee)
The aim of this diploma thesis is to investigate the removability of microplastsic particles with different shapes (fragments, sphers, fibers) by standard water treatment process, such as coagulation, filtration and sedimentation. For the experimental purpose in this study, polyvinyl chloride with a size ≤ 50 μm and a density of 1.38 g/cm3 , was used as a representative of microplastics. The coagulation has been provided by ferric sulphate in pH range 5, 6, 7 and 8 and at a diferent dose of coagulant 20, 40, and 60 mg/l. The study results has shown, that the coagulation efficiency of polyvinyl chloride particles were affected by pH. The optimal value of pH has been 7 at the coagulant dose of 20, 40 and 60 mg/l. The presence of polyvinyl chloride shown a positive effect on coagulation. It has been reflected in a reduction of the residuals of iron concentration after coagulation, at pH 5-7. Solution with polyvinyl chloride contained 1,2 mg/l dissolved organic carbon. After fitlration the concentration decreased up to 70 % at pH 7 at dose of coagulant 40 and 60 mg/l. Experiments have shown that polyvinyl chloride particles are capable of faster sedimentation after coagulation. The flocs formed during coagulation interacted effectively with the polyvinyl chloride particles and facilitate their removal...
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Study of microplastic sorption properties
Hlaváčková, Hana ; Kučerík, Jiří (referee) ; Řezáčová, Veronika (advisor)
There is currently an effort to replace conventional plastics with biodegradable products that will have the ability to replace these substances. One of the possible biodegradable felt, which is currently being studied in detail, is also poly (3-hydroxybutyrate), which is produced by bacteria. This bachelor thesis deals with the sorption of selected substances on poly(3-hydroxybutyrate) microparticles. Substances whose contamination of water sources is a significant problem today have been selected for this work. Specifically, the sorption of the nonsteroidal anti-inflammatory substance ibuprofen, the triazole fungicide tebuconazole and the most common drug caffeine on PHB particles, which fall in the size of the microplastic group, were studied. The method of liquid chromatography with mass detection was used for analyzes.
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Microplastics in soil
Dvořáková, Alena ; Kučerík, Jiří (referee) ; Doležalová Weissmannová, Helena (advisor)
This bachelor thesis deals with the appraisal of the suitability of infrared spectroscopy for the identification of plastics and microplastics in soils. Available techniques were DRIFT (diffuse reflectance) and ATR (attenuated total reflectance). Mixtures of model soil and pure PET were prepared for analysis in various concentrations. Furthermore, a total of 21 samples of soil and 3 samples of compost were evaluated. The obtained data were used for interpretation of infrared spectra, creation of calibrations of PET using ATR and DRIFT methods. Part of the work was the evaluation of validation models using spectra and basic soil parameters.
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Influence of biodegradable polymers microplastics on properties of soil organic matter
Denková, Pavla ; Řezáčová, Veronika (referee) ; Kučerík, Jiří (advisor)
The microplastics contamination is an issue observed in all environmental compartments. Currently, the trend is to replace the synthetic polymers by biodegradable ones, which are expected to degrade faster due to omnipresent microorganisms. However, this assumption may not correspond with the reality. In nature, biodegradation can last long or not whatsoever and the microparticles of biodegradable polymers can remain in soil the same way as particles of synthetic polymers. The effect of microparticles of biodegradable polymers on soil´s biota has already been studied, but the effect on the properties of soil and water in the soil has not been elucidated yet. This thesis deals with the influence of microparticles of biodegradable plastics on the physico-chemical properties of soil organic matter, especially on the behavior of water in the soil system under arid and semiarid conditions. Microparticles of poly(R-3-hydroxybutyrate), abbreviated as P3HB, were used as a model biodegradable polymer and were introduced into the soil in various concentrations. To determine the evaporation enthalpy of water and stability of water bridges that affect (stabilize) the physical and chemical structure of soil organic matter Differential Scanning Calorimetry (DSC) was used. Simultaneously was also measured their effect on water holding capacity of soil organic matter. Under experimental conditions, P3HB microplastics were found to reduce evaporation enthalpy, which facilitates drying of soil organic matter. Nevertheless, their effect on final water holding capacity was relatively low. Besides, we observed a negative effect on the stability of water molecule bridge that connect segments of soil´s organic components. Thus, P3HB microparticles in soil could pose a risk due to their influence on the water retention mechanism in soil under arid and semiarid conditions.
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Microplastics and their removal from water using sorbents.
Spáčilová, Markéta ; Dytrych, Pavel ; Krejčíková, Simona ; Fajgar, Radek ; Šolcová, Olga
The occurrence of contaminants in water sources, microplastics or other organic pollutants, has been an increasing environmental problem. This issue is related to mapping of their occurrence in an aquatic environment and with finding of possible ways regarding their elimination. The prepared microplastic particles of five most-frequently used plastics (polyethylene, polyamide, polytetrafluoroethylene, polyethylene glycol terephthalate and polystyrene) were characterized by the scanning electron microscopy (SEM), the Raman spectroscopy and the infrared spectroscopy (IR). The obtained microplastic particles were used for preparation of simulated water contaminated with microplastics. The prepared simulated samples of water contaminated with microplastics were used for the development of a methodology for determining the number of contained microplast particles. Furthermore, the possibilities of a microplastic removal from simulated samples by sorbents based on natural bentonites and zeolites were tested. It was confirmed that the effectiveness of sorbents depends on their composition and textural properties and could be increased by their modification.
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Determination of PLA microplastics in soil by using pyrolysis methods
Románeková, Ivana ; Mravcová, Ludmila (referee) ; Kučerík, Jiří (advisor)
Nowadays, plastic waste poses one of the greatest risks to the environment. Plastics affect the environment at all stages of their life cycle. Bioplastics have become widely used as a substitute for conventional plastics, without detailed examination of their behavior in real environmental conditions. As a result, it is assumed that they can accumulate in the environment and the question arose as to how to identify them. The main goal of this thesis is to develop a method based on sample pyrolysis that is suitable for the identification and determination of the amount of PLA microplastics in soil and other solid matrices. Three types of soils and sludge were used for analysis. These matrices were spiked to obtain concentration ranges 0,2% - 5,0%. The pyrolysis resulted in evolution of gases with the signals m/z 29, 43 and 44, witch originated from PLA and are suitable for qualitative and quantitative analysis. Analysis of PLA in sludge was more complicated due to similarity of gases evolved from pure matrices. We tested three approaches based on analysis of signal´s peak areas, intensities and temperatures of gas evolution. While the first approach failed, the last two approaches appeared to be promising for qualitative and quantitative analysis of PLA in the sludge. Several methods suitable for qualitative and quantitative analysis of even very small amounts of PLA in soils and sludge have also been designed/developed. These methods were based on analysis of the composition and dynamics of the released gases and the characterisctic degradation temperatures.
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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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