Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 15 of 15 for “"Oxygen Permeation"”.
-
Oxygen permeation and thermo-chemical stability of oxygen separation membrane materials for the oxyfuel process
… which consists in the burning of coal in an oxygen-rich atmosphere to produce a flue gas highly concentrated in CO2, is a technology considered for zero CO2 emission coal-fired power plants. The production of this O2-rich combustion gas from air can be carried out using high purity oxygen …
-
High oxygen permeation rates through poly(dimethyl siloxane) for fuel cells and oxygen reduction reaction mechanistic studies
The electrochemically catalyzed oxygen reduction reaction (ORR) is essential to operation of most fuel cells and many types of batteries; oxygen, being prevalent in air, provides a costless, ambient, high-energy (1.23 V vs. normal hydrogen electrode) hole source to complete the electrochemical …
-
Oxygen Transport Membrane Reactors for Oxy-Fuel Combustion and Carbon Capture Purposes
<p>This thesis investigates oxygen transport membrane reactors (OTMs) for the application of oxy-fuel combustion. This is done by evaluating the material properties and oxygen permeability of different OTM compositions subjected to a variety of operating conditions. The scope of this work consists …
-
Oxygen transport in Ba(Fe,Co,Zr)O 3 - delta membranes
… is measured as a function of temperature and oxygen activity by TG. Very high nonstoichiometry (delta0=0.78 at a(O2)=1) is determined at 1273 K. From the nonstoichiometry of Ba(Fe,Co,Zr)O3-delta;, exponent n (n=-0.01) in Cv=C0v•a(O2)n, thermodynamic factor (gamma=140) and activation energy for …
-
Numerical simulations of ion transport membrane oxy-fuel reactors for CO₂ capture applications
… performed to investigate the key features of oxygen permeation and hydrocarbon conversion in ion transport membrane (ITM) reactors. ITM reactors have been suggested as a novel technology to enable air separation and fuel conversion to take place simultaneously in a single unit. Possessing the …
-
Experimental study and modeling analysis of ion transport membranes for methane partial oxidation and oxyfuel combustion
… Both require significant quantities of oxygen, whose production can impose considerable energy and economic penalties. Alternative technologies, such as intermediate-temperature ceramic membranes, operating under reactive conditions, promise to ameliorate both. Challenges include the …
-
Experimental characterization of an Ion Transport Membrane (ITM) reactor for methane oxyfuel combustion
… Membranes (ITM) which conduct both electrons and oxygen ions have been investigated experimentally for oxygen separation and fuel (mostly methane) conversion purposes over the last three decades. The fuel conversion investigations typically involve converting methane to syngas or higher …
-
Defect chemistry, transport properties and thermodynamic stability of acceptor doped and undeoped layered La 2 NiO 4
The market for oxygen has grown significantly because many industrial processes require oxygen. At present oxygen is produced on industrial scale mainly by cryogenic distillation of air. This is a very energy intensive process and economic operation is possible only on a large scale. An alternative …
-
Charakterisierung perowskitischer Hochtemperaturmembranen zur Sauerstoffbereitstellung für fossil gefeuerte Kraftwerksprozesse
… Here, the materials should produce the required oxygen more energy-efficient than cryogenic air separation. High-temperature materials which are applicable for this purpose are gastight and exhibit a high oxygen permeation rate and a preferably low thermal expansion coefficient. Moreover, the …
-
A NOVEL MEDIATED OXYCOMBUSTION SYSTEM: SUBSYSTEM EVALUATION AND INTEGRATION
… The subsystems included a cerium based oxygen transport membrane, transport membrane coatings to assist in the pickup and release of oxygen, and a molten intermediary oxygen carrier. Various doping levels of yttrium and zirconium were investigated, both as singular dopants and in a …
-
Fundamental studies of perovskite related oxide thin films for oxygen electrocatalysis at intermediate temperatures
… currently utilized for applications including oxygen permeation membranes and solid oxide fuel cells (SOFCs), but alternative materials with higher catalytic activity and stability are required for intermediate temperature (500 - 700 °C) oxide electrocatalysts. In this thesis, two promising …
-
Amine functionalization by initiated chemical vapor deposition (iCVD) for interfacial adhesion and film cohesion
… and also act as diffusion barriers against oxygen permeation into the devices. Two applications utilizing this nanoadhesive bonding technique were introduced, including for growth of E. coli in the iCVD-bonded chips and fabrication of gas impermeable microchannels for microparticle synthesis …
-
Strukturelle und elektronische Untersuchungen am hoch sauerstoffdefizitären Mischleiter Ba x Sr 1-x Co 0,8 Fe 0,2 O 3-delta (BSCF)
… materials, such as superconductivity and high oxygen permeability, whereas these properties are also highly dependent on the surrounding oxygen partial pressure and temperature. In this family of materials, BSCF stands out as it accommodates an extremely high oxygen nonstoichiometry delta which …
-
Towards Mechanical Reinforcement in Polymer Layered Silicates Nanocomposites of the Second Generation
… samples and melt compounded samples showed permeation reductions by 60% and 30%, respectively. Maximizing the interface area by optimum dispersion not only reduced the oxygen permeation but also improved the reinforcement and fracture toughness especially at low clay content. These results …
-
Development of a Humidity-Resistant Coating to Impart High Oxygen Barrier Performance to Food Packaging Films
<p>Oxygen barrier coatings have the potential to greatly extend the lifetime of certain food products by incorporating them into existing food packaging. Present technologies face definite challenges of maintaining high performance, while attaining simple and inexpensive preparation methods. The …