|
|
Microplastics and their removal from water using sorbents.
Spáčilová, Markéta ; Dytrych, Pavel ; Koštejn, Martin ; Fajgar, Radek ; Šolcová, Olga
The increased occurrence of contaminants in water sources, whether microplastics or other organic contaminants, is currently an ever-increasing environmental problem. This issue is closely related to the mapping of their occurrence in the aquatic environment, as well as to possible ways to eliminate them. The work first characterized the characterization of prepared microplastic particles of the five most commonly used plastics (polyethylene, polyamide, polytetrafluoroethylene, polyethylene glycol terephthalate and polystyrene) using scanning electron microscopy (SEM), Raman spectroscopy and infrared spectroscopy (IR). These microplastic particles were used to prepare simulated microplastic contaminated waters. A methodology for determining the number of microplast particles contained was developed on these water samples. Furthermore, the method of their removal from samples with simulated contamination using functional sorbents was tested. Sorbents based on natural bentonites and zeolites were mainly used. It has been confirmed that the effectiveness of these materials depends not only on their composition and textural properties, but can also be increased by modifying them.\n
Plný tet:  PDF
|
|
|
Study of the medium influence on the pollutants sorption on microplastics
Hamplová, Marie ; Kučerík, Jiří (referee) ; Mravcová, Ludmila (advisor)
With the increasing production of plastic waste, the pollution of the environment by persistent microplastics is increasing simultaneously. Other environmental pollutants, such as various pharmaceuticals, can be sorbed on microplastics. This increases the toxicity of microplastics and their risk to living organisms. Nowadays, the use of so-called biodegradable polymers, which are supposed to degrade spontaneously, is expanding. However, their degradation can also produce microplastics. Therefore, this bachelor thesis deals with the sorption of drugs onto microplastics from biodegradable polyhydroxybutyrate (PHB) and with the influence of the surrounding aqueous environment on the rate and mechanism of sorption. Sorption of drugs onto microplastics made of synthetic polyethylene terephthalate (PET) was also carried out for comparison. The quantity of drugs was analysed by UPLC-ESI-TQ. Sorption was observed from the drug mixture for antibiotics tetracyclines. The pH value of the surrounding environment influenced the sorption rate of tetracyclines, the highest sorption occurred at acidic pH 4. According to the results of evaluation of sorption by Langmuir and Freundlich adsorption isotherms, PHB microplastics have a higher sorption capacity than PET microplastics. Therefore, PHB microplastics could be a risk for living organisms.
|
|
|
Interactions between microplastics and heavy metals in the aquatic environment
Ottová, Michaela ; Pavlovský, Jiří (referee) ; Doležalová Weissmannová, Helena (advisor)
This diploma thesis deals with the adsorption of heavy metal ions on the microplastic. Specifically, lead, chromium, zinc, copper, mercury and polyethylene terephthalate was chosen as the plastic representative. Atomic absorption spectrometry (F-AAS, AMA) and FTIR with method ATR were used for the analysis. The aim of this work was to perform selected adsorption experiments, to determine the adsorption kinetics and the maximum amount adsorbed. Subsequently, the most suitable kinetic and isothermal model was determined for each element and the characteristic parameters were calculated.
|
|
| |
|
|
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...
|
|
|
Problems of plastics and microplastics in FTIR analysis of soils
Stanislavová, Veronika ; Kučerík, Jiří (referee) ; Doležalová Weissmannová, Helena (advisor)
Microplastics are formed as the result of the fragmentation of plastics. The microparticles are easier to distribute and thus can contaminate the environment. Recently, there has been an increasing interest in the research of microplastics present in the soil system, using different methodologies. The focus of this thesis is the analysis of microplastics in soil using infrared spectroscopy – ATR (attenuated total reflectance) and DRIFT (diffuse reflectance) techniques. This work aimed to evaluate the suitability of the method for the identification of microplastics in soils. Polymers such as polyethylene terephthalate (PET), poly-3-hydroxybutyrate (PHB) and polylactic acid (PLA) were used. In the first part of experimental analysis were microplastics mixed in different concentrations with 3 different types of model soils. The obtained infrared spectra of samples of mixtures (model soil and plastics) were used for statistical evaluation. The second part of the measurement was focused on the monitoring of changes in the spectra of real soils spiked with PET, after exposure to the degradation. After the interpretation of infrared spectra of samples of plastics with real and model soil, it was possible to confirm the presence of the functional groups of each polymer. Based on the measurements, the used techniques were evaluated as inappropriate for the qualitative determination of PLA. The results of the experimental part confirm the accuracy of FTIR (both ATR and DRIFT) for the analysis of microplastics in soil for samples containing PET and PHB.
|
|
|
Study of selected antibiotics sorption on polyhydroxybutyrate
Amrichová, Anna ; Doležalová Weissmannová, Helena (referee) ; Řezáčová, Veronika (advisor)
The bachelor thesis deals with the issue of sorption of antibiotics on microplastics. Antibiotics and microplastics are now a highly studied topic, due to the positive and negative properties. Antibiotics with groups of sulfonamides and quinolones were selected for the experiment. From sulfonamides, sulfamethoxazole and trimethoprim were selected, and from the quinolones, enrofloxacin and ciprofloxacin, which have already been the impetus for some microplastic studies. Biodegradable polyhydroxybutyrate was used as the microplastic. Two experiments were performed in the laboratory. The first aimed to monitor the time dependence of antibiotic sorption on polyhydroxybutyrate, the second the concentration. The concentration dependence was subsequently evaluated using the Freundlich and Langmuir isotherms. The method of liquid chromatography with mass spectrometry was used for analyzes.
|
|
|
FTIR analysis of soils containing plastics and microplastics
Sinčáková, Lenka ; Pavlovský, Jiří (referee) ; Doležalová Weissmannová, Helena (advisor)
This bachelor thesis deals with the sources of microplastics in soils, their potential toxicity for men as well as the environment and soil-plastic interaction. It provides an overview of methods that are commonly used for qualitative and quantitative characterisation of microplastics in soils with focus on FTIR spectrometry. In the experimental part, real soil samples were evaluated with the use of ATR-FTIR based on model soils-microplastics mixtures calibrations. Vaidation models for model mixtures and carbon content were also evaluated.
|
|
|
Removal of Contaminants from Water.
Spáčilová, Markéta
This study deals with commonly used plastics; polystyrene (PS), polytetrafluorethylene (PTFE), polyamide (PA), polyethylene glycol terephthalate (PET), polyethylene (PE), etc. Microplastic samples were prepared by abrasion from commonly available plastics to simulate real microplastic occurrence in the environment. Prepared samples were characterized by scanning electron microscopy (SEM), Raman spectroscopy and infrared spectroscopy (IR) to obtain their fingerprints. These characteristics can be applied as standards for characterization of real microplastics.
Plný tet: PDF
|
|
|
Microplastics removing from water
Ermis, Martin ; Himr, Daniel (referee) ; Štigler, Jaroslav (advisor)
This thesis deals with the occurrence of microplastics in water, the reasons for their potential elimination, and the possibilities leading to that. More specifically, it focuses on flotation as a process for removing microplastics from water. Flotation is further described from a theoretical point of view and its mathematical model is developed. The wettability of selected polymers is measured. The experiment performed to determine the efficiency of flotation as a process of treating water from microplastics is described. This efficiency is further compared to measured wettability.
|
guest ::
