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What happens to microplastics in nature
Spáčilová, Markéta
This work was focused on preparation of microplastic particles which correspond to microplastics in the environment. The five most used plastics (polyethylene, polyamide, polytetrafluoroethylene, polyethylene glycol terephthalate, and polystyrene) were used for preparation. Microplastics were prepared by grinding common used plastics to match the actual microplastics present in the environment as closely as possible. The shape and size of the prepared particles\nwere obtained by scanning electron microscopy. Raman and infrared spectroscopy were used to characterize the microplastic structures. Simultaneously, methodology to determine the amount of microplastic particles in simulated water samples was developed.
Plný tet:  PDF
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Biochars as effective sorbents for pollutant removal.
Spáčilová, Markéta ; Krejčíková, Simona ; Čárský, Milan ; Soukup, Karel ; Šolcová, Olga
Contaminants in water, various drugs, detergents or microplastics, have been a constant problem. One of the effective methods of their removal is sorption by various active sorbents such as biochar. Four various sorbents were tested in this study. Three biochars prepared from different waste plant biomass (sunflower husks, seaweed and microalgae) and commercial activated carbon - Supersorbon. The effectiveness of the sorbents was tested by diclofenac (active substance) and triclosan (disinfectant) removal. The concentration 1 ppm, which corresponed to the commonly occurring concentration was chosen for tests.\nBased on obtained results, it was found that all biochar sorbents were comparatively effective as activated carbon and thanks to their lower price, also economically advantageous.\n
Plný tet: PDF
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Biochars - effective sorbents for pollutant removal.
Spáčilová, Markéta ; Krejčíková, Simona ; Čárský, Milan ; Soukup, Karel ; Šolcová, Olga
The growing amount of contaminants in the water has been a serious problem. Sorption is one of the effective methods for removal of various contaminants, such as drugs, detergents, or microplastics. Various sorbents are applied, whether commercial or laboratory prepared, as zeolites, bentonites, activated carbon and, more recently, various types of biochar, which are prepared by pyrolysis from variety of biomass residues. Their surface varies according to the preparation conditions (max SBET around 300 m2 / g) and there are tested under various conditions on variety of contaminants. Comparative studies of different types of biochar are rather lacking, similarly as their comparisons with commercial sorbents such as activated carbon.\nFor these reasons, this study aims to compare the sorption properties of three biochars prepared from different types of plant biomass (sunflower husks, seaweed Ecklonia Maxima and freshwater microalgae Chlorella Vulgaris), whose sorption properties were compared with commercial activated carbon, Supersorbon. The effectiveness of sorbents has been tested on diclofenac (a non-steroidal anti-inflammatory and anti-rheumatic drug) whose consumption is enormous worldwide and it is commonly found in water, owing to that most wastewater treatment plants do not capture it. All sorbents showed considerable efficiency, with the best results being obtained using a biochar prepared from freshwater microalgae (95%). Its high effectiveness has been verified in removing the contaminant triclosan (antibacterial and antifungal disinfectant). The concentration of contaminants (1 ppm) was chosen for testing, which corresponds to the concentrations commonly found in wastewater. Based on the result, it was found that all prepared sorbents are comparable effective with activated carbon, however, their preparation is more economically advantageous, because the price of activated carbon increases the need for subsequent activation. \n\n
Plný tet:  DOCX
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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
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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
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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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