97 research outputs found
Freitag, Walburga Katharina/ Buhr, Regina/ Danzeglocke, Eva-Maria/ Schröder, Stefanie/ Völk, Daniel (Hrsg.) (2015). Übergänge gestalten
High Ethylene Production through ODHE Membrane Reactors based on Fast Oxygen-Ion Conductors
This is the peer reviewed version of the following article :Lobera González, MP.; Escolástico Rozalén, S.; Serra Alfaro, JM. (2011). High Ethylene Production through ODHE Membrane Reactors based on Fast Oxygen-Ion Conductors. ChemCatChem. 3:1503-1508. doi:10.1002/cctc.201100055, which has been published in final form at http://dx.doi.org/10.1002/cctc.201100055. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.[EN] High ethylene productivity through the oxidative dehydrogenation
of ethane has been achieved in a catalytic membrane
reactor based on a highly solid-state oxygen permeable material
(Ba0.5Sr0.5Co0.8Fe0.2O3 d). Ethylene is selectively produced by
avoiding the direct contact of molecular oxygen and hydrocarbons,
thereby minimizing the oxygen concentration in the
reaction side. Another key aspect in the process is the dilution
of ethane in the feed to achieve high ethylene yields. There
exists a specific combination of the ethane concentration and
feed flow that maximizes ethylene productivity, whereas the
diluting gas nature has a direct impact on the formation of
higher olefins and coking issues. Indeed, the use of methane
as an almost-inert dilutant allows the reduction of oligomerization
and aromatization of the formed ethylene and therefore
improves the reactor stability even at operating temperatures
from 800 to 900 8C. This behavior is attributed to the competitive
adsorption of methane and ethane/ethylene, the modification
of the radical-driven homogeneous reaction, and the
change of partially reducible membrane surface. The productivity
values achieved at 8508C were 383 mLmin 1cm 2 for Ar
and 353 mLmin 1cm 2 for CH4, with a selectivity of 80 and
90%, respectivelyFinancial support by the Spanish Ministry for Science and Innovation (Project ENE2008-06302 and FPI Grant JAE-Pre 08-0058), the European Union through FP7 NASA-OTM Project (NMP3-SL-2009228701), and the Helmholtz Association of German Research Centres through the Helmholtz Alliance MEM-BRAIN (Initiative and Networking Fund) is kindly acknowledged.Lobera González, MP.; Escolástico Rozalén, S.; Serra Alfaro, JM. (2011). High Ethylene Production through ODHE Membrane Reactors based on Fast Oxygen-Ion Conductors. ChemCatChem. 3:1503-1508. https://doi.org/10.1002/cctc.201100055S15031508
Microwave assisted heterogeneous catalysis: effects of varying oxygen concentrations on the oxidative coupling of methane
The oxidative coupling of methane was investigated over alumina supported La2O3/CeO2 catalysts under microwave dielectric heating conditions at different oxygen concentrations. It was observed that, at a given temperature using microwave heating, selectivities for both ethane and ethylene were notably higher when oxygen was absent than that in oxygen/methane mixtures. The differences were attributed to the localised heating of microwave radiation resulting in temperature inhomogeneity in the catalyst bed. A simplified model was used to estimate the temperature inhomogeneity; the temperature at the centre of the catalyst bed was 85 °C greater than that at the periphery when the catalyst was heated by microwaves in a gas mixture with an oxygen concentration of 12.5% (v/v), and the temperature difference was estimated to be 168 °C in the absence of oxygen
Ethylene Production by ODHE in Catalytic Modified Ba0.5Sr0.5Co0.8Fe0.2O3 Membrane Reactors
[EN] Process intensification by the integration of membranes and high-temperature reactors offers several advantages with regard to conventional process schemes, that is, energy saving, safe operation, reduced plant/unit size, and higher process performance, for example, higher productivity, catalytic activity, selectivity, or stability. We present the study of oxidative dehydrogenation of ethane at 850 8C on a catalytic membrane reactor based on a mixed ionic¿electronic conducting membrane. The surface of the membrane made of Ba0.5Sr0.5Co0.8Fe0.2O3 d has been activated by using different porous catalytic layers based on perovskites. The layer was deposited by screen printing, and the porosity and thickness was studied for the catalyst composition. The different catalyst formulations are based on partial substitution of A- and B-site atoms of doped strontium ferrite/cobaltites (A0.6Sr0.4Co0.5Fe0.5O3 d and Ba0.6Sr0.4BO3 d) and were synthesized by an ethylenediaminetetraacetic acid¿citrate complexation route. The use of a disk-shaped membrane in the reactor enabled the direct contact of gaseous oxygen and hydrocarbons to be avoided, and thus, the ethylene content increased. High ethylene yields (up to 81%) were obtained by using a catalytic coating based on Ba0.5Sr0.5Co0.8Fe0.2O3 d, which included macropores produced by the addition of graphite platelets into the screen-printing ink. The promising catalytic results obtained with this catalytically modified membrane reactor are attributed to the combination of 1) the high activity, as a result of the high temperature and oxygen species diffusing through the membrane; 2) the control of oxygen dosing and the low concentration of molecules in the gas phase; and 3) suitable fluid dynamics, which enables appropriate feed contact with the membrane and the rapid removal of products.Financial support by the Spanish Ministry for Science and Innovation (Project ENE2008-06302, ENE2011-24761 and FPI Grant JAE-Pre 08-0058), the EU through the FP7 NASA-OTM Project (NMP3-SL-2009-228701), and the Helmholtz Association of German Research Centres through the Helmholtz Alliance MEM-BRAIN (Initiative and Networking Fund) is kindly acknowledged. We thank S. Jimenez for material preparation, M. Fabuel for TPD experiments, and Forschungszentrum Julich for SEM analysis of BSCF catalytic layer.Lobera González, MP.; Escolástico Rozalén, S.; García Fayos, J.; Serra Alfaro, JM. (2012). Ethylene Production by ODHE in Catalytic Modified Ba0.5Sr0.5Co0.8Fe0.2O3 Membrane Reactors. ChemSusChem. 5:1587-1596. https://doi.org/10.1002/cssc.201100747S15871596
Application of microemulsion method for development of methanol steam reforming Pd/ZnO catalysts
Estimation of Average Crystallites Size of Active Phase in Ceria-Supported Cobalt-Based Catalysts by Hydrogen Chemisorption vs TEM and XRD Methods
Implementation of the service to search and compare car parts
Projekt został zrealizowany na potrzeby pracy magisterskiej na kierunku Informatyka Stosowana Uniwersytetu Jagiellońskiego. W dobie postępującej informatyzacji i dużego zainteresowania tematami motoryzacyjnymi, konieczne jest odpowiednie zarządzanie częściami samochodowymi. Dostarczone narzędzie jest bazą produktów oraz wszelkich informacji, które ich dotyczą. System oparty na otwartych rozwiązaniach takich jak Apache, Spring, Java oraz Vaadin umożliwia szerokiemu gronu odbiorców szybki dostęp do narzędzi oraz części motoryzacyjnych. Wykorzystanie robota internetowego pozwoliło uzyskać kompletny zestaw danych, potrzebnych do realizacji zadania.The project was realized for the purpose of the MA thesis on Applied Computer Science of the Jagiellonian University. In the era of progressive computerization and great interest in automotive issues, it is necessary to manage the car parts in a timely manner. The tool provided is the product base and any information that is relevant to them. Open systems such as Apache, Spring, Java, and Vaadin provide a wide range of users with fast access to tools and parts. The use of the internet robot allowed us to obtain the complete set of data needed to complete the task
A New Non-Intrusive Condition Monitoring System Designed to Improve Reliability of the RCD
Managed pressure drilling (MPD) is a technology that allows for precise wellbore pressure control, especially in formations of uncertain geomechanics. The rotating control device (RCD) is a crucial part of the MPD equipment but is prone to failure. Therefore, a new condition monitoring system was developed to improve the reliability of RCDs and eliminate their catastrophic failures during MPD jobs. Non-intrusive sensors were selected during the design of this condition monitoring system. Sensors are measuring: vibrations, acoustic emissions, rotation, pipe movement, temperatures, and contamination level in the coolant fluid. The system can display the measurements in real-time to the operator, giving early warnings to prevent the RCD's catastrophic failures during the job. Additionally, the data is recorded to allow further processing and analysis using ML and AI techniques
Catalysts for the utilization of methane from the coal mine ventilation air
The paper indicates coal mines as the source of permanent emission of low-concentrated gases, which have increased the greenhouse effect. This paper proposes the catalytic oxidation of methane as the solution to the problem of methane utilization when its concentration in the air is insufficient for flame combustion. The studies which have been conducted for many years enabled finding the active oxide and metallic catalytic systems for the reaction of methane oxidation. For the utilization of gases with low-concentrated methane, using the low-temperature catalysts, especially palladium catalysts, seems to he economically well-justified. Depending on technological solutions it can be considered as the method for methane utilization or as an environmentally friendly way for the generation of electric and thermal energy
The Influence of Nickel Dispersion in Ni/AlO Catalysts on Their Properties in the Reaction with Hydrogen, Hydrocarbons and Steam
Nickel catalysts are commonly used in many industrial processes including the hydrogenation, hydrotreating, hydrogenolysis, methanation and steam reforming of hydrocarbons. The aim of the present paper was to describe the influence of various physicochemical properties of nickel-supported catalysts on the course of coking in the steam reforming of n-butane as well as the influence of the concentration of B 5 sites on the surface of the catalyst on the course and mechanism of the hydrogenolysis of simple alkanes
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