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Study of adsorption of organic pollutants on wheat bran biochar
Hanák, Jan ; Pořízka, Jaromír (referee) ; Diviš, Pavel (advisor)
This diploma thesis explores the application of the Diffusive Gradients in Thin Films (DGT) method for determining and monitoring the concentrations of dissolved pharmaceuticals and organic dyes in water and food. The theoretical part introduces the issue of the occurrence of these organic substances in water and food, the principles of the DGT method, the characteristics of adsorption and adsorption isotherms, and the introduction of biochar as an adsorbent. The experimental section primarily focuses on optimizing and validating adsorption gels containing commercial biochar and unmodified biochar from wheat bran for the adsorption of specific substances using the DGT method. Oxytetracycline was primarily tested from a selection of antibiotics and malachite green from organic dyes, which is widely used in aquaristics. The results demonstrate a comparison of the effectiveness of adsorption using these two types of adsorbents and their characteristics, such as infrared spectroscopy analysis or images from a scanning electron microscope. From the Langmuir isotherm, the maximum adsorption capacity for oxytetracycline on commercial biochar was found to be 314,065 mgg-1 and the maximum adsorption capacity for wheat bran biochar was 89,720 mgg-1. The maximum adsorption capacity of commercial biochar for malachite green was 439,406 mgg-1. The work further emphasizes the potential of the DGT method as a tool for food analysis and investigating contaminants in water systems, which further move into the food chain.
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Analysis of organic compounds in the soil-biochar-salad system
Hlaváčová, Josefína ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
The bachelor’s thesis presented focuses on the analysis of polycyclic aromatic hydrocarbons extracted from lettuce, soil, biochar and soil mixed with biochar. Polycyclic aromatic hydrocarbons are introduced into the biochar during the production process, i.e., pyrolysis. After applying the biochar to the soil, the polycyclic aromatic hydrocarbons can be released into the soil and contaminate it. The theoretical part of the thesis focuses on the production and characterisation of biochar, its applications to the soil and subsequent changes it induces within the soil. The experimental part focuses on the optimization of the microwave-assisted extraction process. Furthermore, experiments were carried out, assessing the influence of the added biochar on the concentration of polycyclic aromatic hydrocarbons within soil and lettuce. The sample analysis included microwave-assisted extraction and quantitative and qualitative determination using GC/MS/MS. The samples analysed were assessed for the presence and concentration of 16 different polycyclic aromatic hydrocarbons, prioritised by the U.S. Environmental Protection Agency. The analysis of the samples of lettuce grown in the soil containing biochar display a higher concentration of polycyclic aromatic hydrocarbons compared to samples without biochar. The analysis of the lettuce roots showed identical results.
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Determination of content of organic compounds in biochar
Novotná, Martina ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
Biochar is created during the pyrolysis of organic biomass. Once added into the soil, it can improve its features. Biochars made from sewage sludge have various compositions. It is because of the vast difference between entrance materials. Organic pollutants can be absorbed into its surface during the cooling proces sof pyrolysis. If released into the enviroment, these compounds can cause inhibition of plant growth, get into food chains and adversely affect living organisms. Organic pollutans are determined most often by GC/MS after organic solvent extraction.
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Preparation and basic chemical and physical characterization of biochar from wheat bran
Zouharová, Kamila ; Diviš, Pavel (referee) ; Pořízka, Jaromír (advisor)
At present, the extraction of biochar and its use is a much-discussed topic in the chemical and research fields. The use of biochar is very often declined in the areas of agriculture, waste management, environmental improvement and the fight against global warming. In addition to these sectors, the topic of biochar is also addressed in the production of bio-diesel and bio-oil. Due to the current use of secondary products during biotechnological processes, the presented theoretical and practical study focused on the issue of obtaining biochar from bran by pyrolysis at different temperatures. Part of the practical part was the extraction of biochar from bran and its subsequent analysis, which could be used to characterize biochar obtained from bran by pyrolysis physically and chemically. The characterization of bran biochar was solved by various analytical methods. These techniques yielded, for example, pH, conductivity, particle distribution, elemental composition of biochar, porosity and content of polycyclic aromatic hydrocarbons. Thanks to this study, the properties of biochar and its possible applications in everyday life were characterized in detail. Given the very promising use of biochar obtained from bran, it can be said that this will be a very desirable topic for the future.
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The influence of biochar on physico-chemical properties of soil
Polášková, Nikola ; Sedláček, Petr (referee) ; Smilek, Jiří (advisor)
This thesis is focused on assessment of the influence of biochar on the soil physico-chemical properties (particle density, dry density, porosity, water retention capacity and maximum water holding capacity, oxidizable carbon content, total nitrogen content, phosphorus, potassium and magnesium content). The selected and examined soil types were: cambisol, fluvisol, chernozem and regosol. There were two types of biochar used for analysis – NovoTerra and Sonnenerde. Soil samples were dried to constant weight and adjusted to grain-size fraction under 2 mm, respectively 0,25 mm. The oxidizable carbon content was measured by oxidation using a mixture of potassium dichromate and sulphuric acid (Walkley-Black method), the total nitrogen content was measured by kjeldahlization and P, K and Mg content was measured using Mehlich 3 extraction and ICP-OES spectrometer. The results show that biochar has a significant influence on soil characteristics depending on the type of biochar and soil we use for biochar application. This thesis can be used to clarify the complex issues in terms of soil in Czech Republic or it can be used by farmers considering using biochar as a soil additive with the intention to increase productivity and fertility of soil.
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Study and characterization of organic substances in a biochar sample
Vojáčková, Beáta ; Kalina, Michal (referee) ; Enev, Vojtěch (advisor)
This bachelor thesis characterizes biochar from a physico-chemical point of view. The theoretical part deals with biochar as a soil conditioner, its properties, use, production, and last but not least, effect of its sorroundings. For better characterization of organic and inorganic matter a phosphate buffer was used. This buffer ensures their specific extraction due to a neutral pH. The second path is to use rainwater, which simulates the condition of the soil environment. In the experimental part are discussed both; purified buffer-extracted samples and rainwater samples, which were studied by thermogravimetric analysis (TGA), elemental analysis (EA) and by infrared spectroscopy with Fouier transform (FTIR-ATR). Conductivity and pH were also measured. Moisture and ash content, which represent the inorganic non-combustible fraction, were determined using thermogravimetry. The extraction yields were converted to ashless wt. % based on these values. Results of EA provided us with information on the content of biogenic elements and basic physico-chemical characteristics of biochar. In contrast, the FTIR method defined the presence of individual functional groups and specific constitutive units, which are present in the extracts. This information allows us to better understand the environmental impact of biochar on the soil ecosystem.
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Determination of organic compounds in biochar produced by microwave torrefaction of biomass
Meindl, Jiří ; Vávrová, Milada (referee) ; Mravcová, Ludmila (advisor)
The thesis is focused on a determination of polycyclic aromatic hydrocarbons (PAHs) contained in dried pelletized sewage sludge and pelletized biochar. Biochars were made in mild conditions by microwave torrefaction of prepared sewage sludge. There were analyzed and quantified the 34 of standardized PAHs compounds in two series. The first serie, also called “Sada 1”, has been aimed at comparison of extraction methods for the chosen sample of sewage sludge and the sample of biochar. In serie “Sada 1”, there were compared efficiencies of chosen type of solvent or solvent mixture by comparison of yields for 34 standardized analytes in a sample of biochar and a sample of sewage sludge. There were compared also to total yields of PAHs and to number of quantified compounds in analyzed samples. The most reliable extraction method has been used for the next analyses of samples in the second serie called “Sada 2”. In Sada 2, there were compared different samples of the same type (e.g. biochar, sludge). The origin of sewage sludge (small or big sewage treatment plant expressed as PE) and used additives (cellulose, chaff, hay) as modificators for torrefaction process were variables for different type of sample. The results of analysis were identification of the most suitable sewage sludge and additive to be used as modificator for microwave torrefaction process. The main goal of correctly chosen sludge and additive was to minimize production of PAH’s during torrefaction and in samples of biochar.
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Optimization of the Methodology for Assessment of Biochar Effect on the Growth of Model Plants
Štorková, Natálie ; Enev, Vojtěch (referee) ; Kalina, Michal (advisor)
This bachelor thesis is studying the effect of biochar on the growth of model plant and deals with the optimalization of the methods for assessing its impact. Theoretical part describes the properties and utilization of soil conditioners, special attention is focused on biochar. According to the literature research, maize (Zea mays) was chosen as a model plant for cultivation experiment and subsequently the application doses of biochar were also defined. The cultivation experiment took place in growing box under controlled illumination and irrigation. Plant dry weight weighing after cultivation, continuous measurement of plant height during the cultivation and also image analysis of the root system were used for evaluating the influence of biochar on quantitative and qualitative properties of model plants. From obtained data it can be summarized that the growth differences were influenced by the application dose, the type of biochar and also by type of soil, which was used for the cultivation experiment.
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Production and characterization of biochar derived from different kind of bran
Černíková, Eliška ; Kalina, Michal (referee) ; Pořízka, Jaromír (advisor)
The bachelor thesis was focused on production and characterization of biochar prepared from different sorts of bran. According to the philosophy of circular economy bran, the biproduct of flour production, was chosen for the production of biochar. This lignocellulosic material was walked through pyrolysis to broaden potential application. Biochar was prepared by slow pyrolysis and considering its properties multiple applications are possible. Biochar’s usage is limited by European Biochar Certificate. The theoretical part contains general description of biochar properties, requests of European Biochar Certificate and possible analytical methods. In the practical part process of biochar preparation and biochar characterization per chosen methods are described. Analysed properties were: specific surface, pH, particle size distribution, electrical conductivity, composition of elements and content of polycyclic aromatic hydrocarbons. Based on measured data possible applications were recommended. Only biochar from rye bran fulfilled the strict criteria of European Biochar Certificate. However all of the prepared materials can be used in agriculture, except from rice bran biochar which according to EBC can only be used in material industry.
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Study of the effect of fertilizer containing wheat bran on lettuce growth
Smrčková, Kamila ; Pořízka, Jaromír (referee) ; Diviš, Pavel (advisor)
The aim of the work was to perform growth experiments on a laboratory scale with soil, which was enriched with 2,5 vol. % of wheat bran/coffee grounds/biochar and to study soil and growth characteristics on Lactuca sativa L. The coffee grounds were added raw or modified by oxidation/extraction. Phytotoxic properties of coffee grounds were confirmed by germination tests, although there was an effort to reduce the content of phenolic substances by oxidation /extraction. Soil additives caused an increase in content of organic matter, water capacity, pH and conductivity of all mixtures compared to the control soil. Elemental analysis of soils before cultivation did not show any positive effect on the content of mineral elements compared to the control soil. On the other hand, higher mineral (P, Mg, Ca, K, Mn, Fe, Cu and Al) content compared to soil was recorded cultivation experiments. Chlorophyll a was the most abundant in cultivated plants and reached the lowest concentration in plants grown in a mixture with EXKS. Salads differed in mineral content, too. Salads with the highest content of phosphorus were growed on the mixture BU+OT+PŮDA. On the contrary, content of potassium is salads was negatively affected by mixture with EXKS. Microelements (Fe, Zn, Al, Cu, Cr and Mn) were most affected in the salad by the addition of raw coffee grounds and OXKS2.
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