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Ústí nad Labem, Czech Republic

Krupka J.,Institute of Chemical Technology Prague | Pasek J.,Institute of Chemical Technology Prague | Lederer J.,Research Institute of Inorganic Chemistry VUAnCh | Bilkova D.,Institute of Chemical Technology Prague
Petroleum and Coal | Year: 2014

The kinetics of the formation of isomeric dimers and codimers via thermal dimerization and codimerization between 1,3-cyclopentadiene, isoprene, cis-1,3-pentadiene and trans-1,3-pentadiene were studied. The laboratory experiments were carried out in a batch reactor in a cyclohexane solution at different temperatures. Measured concentrations of the reactants and 1:1 Diels-Alder adducts were fitted to the kinetic model. Kinetic parameters for formation of the individual isomeric products and the summary reactions were determined. It was found that the activation energies of dimerizations of acyclic C5 dienes are by 20-40 kJ/mol higher than that of the dimerization of cyclopentadiene, and the activation energies of the formation of codimers of cyclopentadiene with 1,3-pentadienes are higher by 10-20 kJ/mol. Source


Kubicka D.,Rentech | Cerny R.,Research Institute of Inorganic Chemistry VUAnCh
Industrial and Engineering Chemistry Research | Year: 2012

Synthesis gas originating from alternative feedstocks such as biomass, coal, or natural gas can become an important source of hydrocarbon-based automotive fuels in the future. Fischer-Tropsch synthesis (FTS) affords these hydrocarbons, but upgrading of the primary FTS products is unavoidable. One option is to use the fluid catalytic cracking (FCC) process to convert FTS waxes into a wide range of products. To investigate the impact of FTS wax addition to a conventional FCC feedstock on product yields and properties, microactivity test (MAT) experiments were performed. The tests were performed at 803 K and the catalyst to feed ratio (C/F) was varied in the range 2-4 m/m. The feed contained 0-100% of FTS wax. The addition of FTS wax resulted in increased conversion and yield of the middle distillate fraction (light cycle oil, LCO) and decreased yield of coke. Owing to the increased conversion, higher yields of propylene were obtained by catalytic cracking of feedstocks containing FTS wax. The detailed GC analysis of the products indicated enhanced properties of LCO due to the lowered content of aromatics. © 2011 American Chemical Society. Source


Cerny R.,Research Institute of Inorganic Chemistry VUAnCh | Kubu M.,J. Heyrovsky Institute of Physical Chemistry | Kubicka D.,Rentech
Catalysis Today | Year: 2013

Biomass-derived oxygenates are promising future feedstocks for the chemical industry. Fluid catalytic cracking of these feedstocks has the advantage of enabling their deoxygenation without external hydrogen consumption. Six model feedstocks have been tested using the microactivity test with the aim to describe the impact of the feedstock structure on its conversion and product distribution. It has been shown that saturated alcohols are the feedstocks yielding the most valuable iso-alkanes. Fatty acids and triglycerides yielded more aromatics and with increasing molecular weight the formation of di- and polyaromatics was preferred. When unsaturated feedstocks were used instead of the saturated ones, the formation of aromatics was further augmented. © 2012 Elsevier B.V. All rights reserved. Source


Krupka J.,Institute of Chemical Technology Prague | Kolena J.,Research Institute of Inorganic Chemistry VUAnCh
Petroleum and Coal | Year: 2012

Dimers and codimers resulting from thermal cycloaddition reactions of 1,3-cyclopentadiene, isoprene, cis-1,3-pentadiene and trans-1,3-pentadiene were characterised in terms of their Kovats retention indices on a HP-PONA capillary column at 100°C. The proportion of individual isomers in dimerisation and codimerisation products under defined reaction conditions and their chromatographic characteristics were compared with published data. The chemical structure of isomer products was assigned on the basis of agreement between experimental and literature data. Source


Hidalgo J.M.,Research Institute of Inorganic Chemistry VUAnCh | Kaucky D.,J. Heyrovsky Institute of Physical Chemistry | Bortnovsky O.,Eurosupport Manufacturing Czechia | Cerny R.,Research Institute of Inorganic Chemistry VUAnCh | Sobalik Z.,J. Heyrovsky Institute of Physical Chemistry
RSC Advances | Year: 2015

Many authors have published much information about the isomerization of paraffins C5-C6 using Pt/WO3-ZrO2 materials. Nevertheless, only model feedstocks have been used. An active catalyst was developed with the aim of isomerising industrial feedstocks. This material presented stable activity during the reaction with an increase of the R.O.N. of 14 at 225 °C. The material is the first real candidate for a tungstated zirconia to be used in industry to isomerise light paraffins. This journal is © The Royal Society of Chemistry. Source

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