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Partial Oxidation of High-Boiling Hydrocarbon Mixtures on the Pilot Unit
Hanika, Jiří ; Lederer, J. ; Nečesaný, F. ; Nečesaný, F., jr. ; Poslední, W. ; Tukač, V. ; Veselý, Václav
The research on partial oxidation (POX) of high-boiling hydrocarbons with oxygen in the presence of water vapor was motivated to ensure increased demand on hydrogen, which is essential for a deeper hydrorefining of petroleum oils to ensure better quality of motor fuels. Experiments on improved pilot apparatus installed in Litvínov, UNIPETROL, a.s. have been implemented in cooperation the Institute of Inorganic Chemistry, a.s., Ústí n. l., Institute of Chemical Process Fundamentals AS CR, v. v. i., and Institute of Chemical Technology Prague. In the course of tests have been demonstrated good performance of the pilot plant unit and reproducibility of the experiment as well. A significant impact water vapor on the selectivity of the partial oxidation of high-boiling hydrocarbons with regard to the composition of the exhaust gas was detected in the study. Furthermore, it was stated that hydrogen content of the reaction product being during the partial oxidation of mixture of visbreaking distillate and residue, diluted with pyrolysis fuel oil reached 50 percent. Content of components in a gaseous product was in very good conformity with a synthesis gas composition produced by the plant unit of the UNIPETROL RPA Co., designed and build according to the license of the Shell Co.
Fulltext: content.csg -  PDF
Plný tet: SKMBT_C22013102415180 - PDF
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Optimization and Mathematical Modelling of Hydrodistillation from Eucalyptus grandis and Lippia javanica
Topiař, Martin ; Sajfrtová, Marie ; Sovová, Helena ; Karban, Jindřich
K získání silice z rostlin Eucalyptus grandis a Lippia javanica sloužila hydrodestilace s použitím Clevengerova nástavce. Proměnnými parametry procesu byla doba varu, velikost částic a hydromodul. K vyhodnocení kinetických konstant hydrodestilace obou rostlin byl použit vhodný matematický model1, který počítá s rozdělením destilátu na dva podíly, kdy jeden je extrahován rychleji a druhý pomaleji, přičemž každému podílu přísluší vlastní kinetická konstanta. Mezi hlavní analyzované složky silice z eukalyptu patřil 1,8 cineol, alfa-pinen (8,2 hm. %), aromadenrden a spathulenol. Majoritní složky získané z výtažku lipie byly perillaldehyd, limonen a germacren. Bylo zjištěno, že optimálními parametry z hlediska maximalizace výtěžku jsou doba varu 5 h s poměrem navážka k objemu vody 1:5. Velikost částic nemá u zkoumaných rostlin zásadní vliv na velikost výtěžku. Maximální výtěžek eukalyptové silice dosahoval 26,7 mg/g, zatímco u lipie byl maximální výtěžek poloviční, a to 12,8 mg/g.
Fulltext: content.csg - PDF
Plný tet: SKMBT_C22013102510210 - PDF
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Thin Photoresponding Elements with Frequency and Amplitude Modulations
Klusoň, Petr ; Morozová, Magdalena ; Dzik, P. ; Veselý, M.
Nanoscale templated metal oxide thin films undoubtedly appertain to the most extensively studied materials due to their optical and electrochemical properties. Their photo-induced properties arise from the semiconductor nature, especially from the ability of the light quantum absorption followed by the charge carrier generation. In order to produce metal oxide thin layer layers, the liquid sol containing also the templating bodies, and confining nanoparticles, must be coated onto a substrate. Various coating techniques have been used for this purpose, such as dip-, spin- or spraycoating. Recently a new promising deposition technique has appeared. The novel approach is usually termed piezoelectric jet material deposition or shortly material printing. In this case the ink is the specially formulated liquid purposed for transporting functional components onto the substrate surface. This technique brings the possibility of direct patterning, i.e. the fabrication of 2D patterns on the substrate without the need of any mechanical or optical masking. Material printing has been already employed for the deposition of variety functional materials.
Fulltext: content.csg - PDF
Plný tet: SKMBT_C22013102415160 - PDF
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Micro- and Nanocellular Polymer Foams – Insulation Material of the Future
Nistor, A. ; Rygl, A. ; Bobak, M. ; Sajfrtová, Marie ; Kosek, J.
In the polymer foam industry, emphasis is placed on improving foam properties and making the production process more sustainable and ecological. By reducing the cell size of polymer foams below tens of micrometres we can improve their heat insulation properties and save material. Such polymer foams are called micro- or nanocellular foams depending on the range of their cell size. Micro- and nanocellular foams can be prepared by pressure induced foaming with high pressure CO2. We studied the influence of the foaming conditions on the final foam structure with the aim of achieving the cell sizes as small as possible, having a narrow cell size distribution and reaching the bulk porosity above 90 %. The foam morphology was analysed by Scanning Electron Microscopy and Atomic Force Microscopy. Some morphology visualisations were also made by X-ray micro-tomography, but these visualisations are not demonstrated in this contribution.
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Plný tet: SKMBT_C22013102415151 - PDF
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Photocatalytic Degradation of Bisphenol A
Spáčilová, Lucie ; Maléterová, Ywetta ; Cajthaml, Tomáš ; Šolcová, Olga
Bisphenol A belongs to the group of the environmental estrogens that act as the hormonal system of the body. It is one of the most representative endocrine disruptors in wastewater. Bisphenol A gets into rivers from the production of polycarbonate, respectively, from the processing thereof. More than 75% of the Czech polycarbonate consumption is concentrated in three key economic sectors: automotive, construction, electronics and electrical industry.
Fulltext: content.csg - PDF
Plný tet: SKMBT_C22013102415320 - PDF
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The Deflocculation of Kaolin Suspensions – the Effect of Various Electrolytes
Pěnkavová, Věra ; Guerreiro, M. ; Tihon, Jaroslav
The deflocculation effect of conventional additives to kaolin suspensions is evaluated from the results standard rheological measurements. Several widely used electrolytes (NaOH, Na2CO3, Na2SiO3, SHMP = sodium hexametaphosphate, and CMC = sodium salts of carboxymethylcellulose) have been tested. The optimal concentrations of these deffloculants, in respect to reaching the maximum reduction of initial suspension viscosity, are found. The stability of deflocculated kaolin suspensions against sedimentation is evaluated and different aspects of the observed flow enhancement discussed. Inorganic electrolytes are found to be more effective in viscosity reduction, but on the other hand, low-molecular organic CMC additives produce more stable final suspensions.
Fulltext: content.csg - PDF
Plný tet: SKMBT_C22013102415150 - PDF
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