Thesis (Ph.D)--Mechanical Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Fedorov, Andrei; Committee Co-Chair: Degertekin, Levent; Committee Member: Koros, William; Committee Member: Liu, Meilin; Committee Member: Mayor, J. Rhett. Part of the SMARTech Electronic Thesis and Dissertation Collection.

Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 147-151).

Thesis (Ph.D.)--McMaster University (Canada), 1987. / Source: Dissertation Abstracts International, Volume: 49-07, Section: B, page: 2799. Supervisors: D. A. Thompson; W. W. Smeltzer; J. A. Davies.

Thesis (Ph. D.)--Ohio State University, 2005. / Available online via OhioLINK's ETD Center; full text release delayed at author's request until 2006 Nov 29

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Thesis (MTech (Chemical Engineering))--Cape Peninsula University of Technology, 2016. / The Water Gas Shift (WGS) reaction describes the reaction between carbon monoxide and water vapour to produce carbon monoxide and hydrogen. This work describes the application of a Palladium-Silver (Pd-Ag)-based membrane film reactor, wherein the Pd-Ag film was supported by porous stainless steel (PSS), for the potential replacement of the current multi-stage WGS reaction. The objective of this work was to develop a better understanding of impediments which are relevant to the application of Pd-Ag membrane reactor for the WGSR. The long term behaviour (hydrogen permeability and selectivity) of Pd-Ag membrane under hydrogen exposure was studied, and the use of the Pd-Ag membrane reactor to produce hydrogen through the WGSR was also performed. A detailed literature review was conducted, based on the information gathered from literature. A Permeability and WGS reaction testing stations was designed and built. A thin (20μm) 77%wtPd-23%wtAg film was purchased from Takanaka Company in Japan. The membrane film was enclosed between two stainless steel plates to form a membrane reactor. The membrane reactor was fitted at the two different testing stations.

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To date there has been much work carried out in the field of surface science to gain a better understanding of the fundamentals of a wide range of catalytic systems and reactions. The central theme of this thesis relates to cobalt based Fischer-Tropsch synthesis (FTS) with particular focus on the structure, composition and surface chemistry of CoPd bimetallic systems and on the interaction of Co with oxide support materials. In the work described in this thesis MEIS and STM are used to examine the growth of Co on Pd{111} and to characterise the structure of CoPd alloys created by thermal treatment of thin Co films. MEIS investigations indicate that Co grows initially as an fcc overlayer, but beyond a few layers, a stacking fault exists resulting in hcp growth. On annealing between 550 and 700 K, a previously unreported ordered surface alloy is observed giving rise to a p(2 x 1) structure which is concluded to be the surface termination of an ordered CoPd bulk alloy. At higher annealing temperatures, long range Moiré structure is observed by STM which MEIS reveals to correspond to a Pd-rich alloy. MEIS is used to investigate adsorbate induced segregation effects at CoPd surfaces on Pd{111}. The adsorption of O2, CO, H2 and CO/H2 mixtures (syngas) were all examined on a range of bimetallic surfaces. Oxygen adsorption on CoPd alloys strongly segregates cobalt to the surface as a result of the facile oxidation reaction. The behaviour of the components of syngas was more complex with the most noticeable effects being observed on surfaces which were more defect rich. The growth, annealing behaviour and adsorption properties of Co particles on oxide and mixed oxide surfaces are examined using MEIS and TPD.

Hong Sin Yi, Grace. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 50-51). / Acknowledgments / Abstract / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- Metallic Glass and its application --- p.1 / Chapter 1.2 --- Glass Forming Ability (GFA) --- p.2 / Chapter 1.3 --- Equilibrium Phase --- p.3 / Chapter 1.4 --- Nucleation and Growth --- p.6 / Chapter 1.5 --- Spinodal Decomposition --- p.8 / Chapter 1.6 --- Morphology Comparison between Nucleation and Growth and Spinodal --- p.13 / Figures --- p.14 / References --- p.24 / Chapter Chapter 2 --- Experimental Method / Experimental Method --- p.25 / Figure --- p.29 / References --- p.30 / Chapter Chapter 3 --- Metastable liquid miscibility gap in Pd-Si and its glass forming ability / Introduction --- p.32 / Experimental --- p.33 / Results --- p.34 / Discussion --- p.36 / Figures --- p.40 / References --- p.49 / Bibliography --- p.50

Energy efficient purification of hydrogen is an important technological challenge with broad applications in the chemical, petrochemical, metallurgical, pharmaceutical, textile and energy industries. Palladium-alloy membranes are particularly suited to this problem due to their high hydrogen permeability, thermal stability, and virtually infinite selectivity. In current systems hydrogen flux is observed to be inversely proportional to membrane thickness which is indicative of the interstitial diffusion mechanism of hydrogen permeation. This observation, along with the high cost of palladium, has motivated continuous efforts to decrease membrane thickness. Theoretical modeling of membrane performance predicts that as membrane thickness continues to decrease, eventually the permeation rate will no longer be limited by diffusion through the bulk Pd but will become limited by desorption from the permeate surface. If it exists, this is a vital transition to pinpoint due to the fact that below this thickness membrane operating conditions will have a drastically different effect on hydrogen permeation behavior and no additional performance enhancements will result from further decreasing thickness. A handful of experimental results in the open literature contradict these modeling predictions. A new model is developed in this work to explain these contradictions by considering the non-ideal behavior of hydrogen solution into metals which has been neglected in previous models. Additionally, it has been demonstrated that hydrogen permeation through bulk Pd depends on membrane microstructure, making deposition conditions and post-deposition thermal treatment important issues for repeatable performance. The interplay of these issues on the performance of ultra-thin, Pd-Ag alloy hydrogen separating membranes is experimentally investigated. It is demonstrated that the hydrogen permeation behavior of sub-micrometer thick Pd-Ag alloy membranes exhibits diffusion-limited behavior in the context of the new model. The microstructure evolution during annealing is characterized and a correlation is drawn with the observed transient hydrogen permeation behavior during initial testing of a new membrane. In addition, two distinct failure modes of the microfabricated membranes are observed and the implications for future Pd-based membrane research are discussed.