Download or read book Studies on the System Sodium sodium Hydride hydrogen written by William Louis Rittschof and published by . This book was released on 1940 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Study of the Sodium Hydrogen Oxygen System written by Dale D. Williams and published by . This book was released on 1952 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt: The sodium-hydrogen-oxygen system has been investigated in continuation of the study of impurities in liquid metals. Sodium metal reacts with sodium hydroxide at temperatures above 300 degrees C to form sodium monoxide and sodium hydride. If the reaction is initiated in vacuo, hydrogen will be liberated to the extent of the dissociation pressure of sodium hydride at temperatures below 385 degrees C. If this hydrogen is not removed from the reaction zone, and if the temperature is raised beyond 385 degrees C, an equilibrium is established which does not follow the dissociation pressure diagram for sodium hydride. This new equilibrium appears to be related to the solubility of the reaction products in sodium metal and in sodium hydroxide. The 'keystone' of the equilibrium appears to be the fusion temperature of the melt which, in turn, is determined principally by the ratio of sodium monoxide to sodium hydroxide. Data are presented showing that the dissociation of sodium hydride is suppressed by an inert gas blanket. It is indicated that sodium hydride must vaporize or sublime before it will dissociate. It is further shown that sodium hydride in solution is quite stable, even in vacuo at temperatures well above those at which the hydride should be dissociated. Data for the potassium-hydrogen-oxygen system are entirely different from that reported for the corresponding sodium system. The difference could well be related to a higher solubility of the reaction products in the reactants.(Author).

Download or read book The Sodium hydrogen System written by and published by . This book was released on 1955 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Sodium Hydroxide Sodium Oxide Sodium Sodium Hydride Hydrogen System written by and published by . This book was released on 1957 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Sodium hydride dissolves in and reacts with molten NaOH to give an equilibrium mixture of NaH, NaOH, Na/sub 2/O, Na, and H. In the case where there is a gaseous phase (hydrogen) and only one condensed phase, the system is defined by the temperature, pressure, and one composition variable. The equilibriu, H/ sub 2/ pressure, which is a measure of the H/sub 2/ activity within the melt, was determined as a function of the composition of the condensed phase(s) at 600, 700, and 500 deg for equilibrium mixtures with original compositions of 2.5 to 97.5, 5.0 to 95.0, l0.0 to 90.0, and 20.0 to 50.0 mole% NaH-NaOH. The equilibrium H/sub 2/ pressure-composition isotherms obtained by removing measured increments of H/sub 2/ were reproduced by reabsorbing H/sub 2/. Results for the 5.0 mole % NaH mixture were duplicated by starting with an equivalent quantity of either Na in NaOH or Na/sub 2/O in NaOH, and reacting with measured increments of H/sub 2/. The system is discussed in relation to the interdependent reactions involved, the phase rule, the thermodynamics of certain reactions, and experimental techniques employed. (auth).

Download or read book Studies of Hydrogen Storage in the Sodium Borohydride and Magnesium Nickel Hydride Composite System written by Louis Greg Afonso and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book U S Government Research Reports written by and published by . This book was released on 1964 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Reduction of Rare Earth Salts with Sodium in Liquid Ammonia written by Leon Lee Gershbein and published by . This book was released on 1939 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Hydrogen Storage Materials written by R. G. Barnes and published by . This book was released on 1988 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ames Laboratory, Iowa, USA

Download or read book Journal of the American Chemical Society written by American Chemical Society and published by . This book was released on 1958 with total page 1700 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the Society are included in v. 1-59, 1879-1937.

Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1975 with total page 1090 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Durability Study of a Vehicle scale Hydrogen Storage System written by and published by . This book was released on 2010 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sandia National Laboratories has developed a vehicle-scale demonstration hydrogen storage system as part of a Work for Others project funded by General Motors. This Demonstration System was developed based on the properties and characteristics of sodium alanates which are complex metal hydrides. The technology resulting from this program was developed to enable heat and mass management during refueling and hydrogen delivery to an automotive system. During this program the Demonstration System was subjected to repeated hydriding and dehydriding cycles to enable comparison of the vehicle-scale system performance to small-scale sample data. This paper describes the experimental results of life-cycle studies of the Demonstration System. Two of the four hydrogen storage modules of the Demonstration System were used for this study. A well-controlled and repeatable sorption cycle was defined for the repeated cycling, which began after the system had already been cycled forty-one times. After the first nine repeated cycles, a significant hydrogen storage capacity loss was observed. It was suspected that the sodium alanates had been affected either morphologically or by contamination. The mechanisms leading to this initial degradation were investigated and results indicated that water and/or air contamination of the hydrogen supply may have lead to oxidation of the hydride and possibly kinetic deactivation. Subsequent cycles showed continued capacity loss indicating that the mechanism of degradation was gradual and transport or kinetically limited. A materials analysis was then conducted using established methods including treatment with carbon dioxide to react with sodium oxides that may have formed. The module tubes were sectioned to examine chemical composition and morphology as a function of axial position. The results will be discussed.

Download or read book TID written by and published by . This book was released on 1958 with total page 446 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Hydrides of Metals and Metalloids written by and published by . This book was released on 1960 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Parameter Study of a Vehicle scale Hydrogen Storage System written by and published by . This book was released on 2010 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sandia National Laboratories has developed a vehicle-scale prototype hydrogen storage system as part of a Work For Others project funded by General Motors. This Demonstration System was developed using the complex metal hydride sodium alanate. For the current work, we have continued our evaluation of the GM Demonstration System to provide learning to DOE's hydrogen storage programs, specifically the new Hydrogen Storage Engineering Center of Excellence. Baseline refueling data during testing for GM was taken over a narrow range of optimized parameter values. Further testing was conducted over a broader range. Parameters considered included hydrogen pressure and coolant flow rate. This data confirmed the choice of design pressure of the Demonstration System, but indicated that the system was over-designed for cooling. Baseline hydrogen delivery data was insufficient to map out delivery rate as a function of temperature and capacity for the full-scale system. A more rigorous matrix of tests was performed to better define delivery capabilities. These studies were compared with 1-D and 2-D coupled multi-physics modeling results. The relative merits of these models are discussed along with opportunities for improved efficiency or reduced mass and volume.

Download or read book Proceedings written by and published by . This book was released on 1961 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Discovery of Novel Complex Metal Hydrides for Hydrogen Storage Through Molecular Modeling and Combinatorial Methods written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: UOP LLC, a Honeywell Company, Ford Motor Company, and Striatus, Inc., collaborated with Professor Craig Jensen of the University of Hawaii and Professor Vidvuds Ozolins of University of California, Los Angeles on a multi-year cost-shared program to discover novel complex metal hydrides for hydrogen storage. This innovative program combined sophisticated molecular modeling with high throughput combinatorial experiments to maximize the probability of identifying commercially relevant, economical hydrogen storage materials with broad application. A set of tools was developed to pursue the medium throughput (MT) and high throughput (HT) combinatorial exploratory investigation of novel complex metal hydrides for hydrogen storage. The assay programs consisted of monitoring hydrogen evolution as a function of temperature. This project also incorporated theoretical methods to help select candidate materials families for testing. The Virtual High Throughput Screening served as a virtual laboratory, calculating structures and their properties. First Principles calculations were applied to various systems to examine hydrogen storage reaction pathways and the associated thermodynamics. The experimental program began with the validation of the MT assay tool with NaAlH4/0.02 mole Ti, the state of the art hydrogen storage system given by decomposition of sodium alanate to sodium hydride, aluminum metal, and hydrogen. Once certified, a combinatorial 21-point study of the NaAlH4 - LiAlH4 -Mg(AlH4)2 phase diagram was investigated with the MT assay. Stability proved to be a problem as many of the materials decomposed during synthesis, altering the expected assay results. This resulted in repeating the entire experiment with a mild milling approach, which only temporarily increased capacity. NaAlH4 was the best performer in both studies and no new mixed alanates were observed, a result consistent with the VHTS. Powder XRD suggested that the reverse reaction, the regeneration of the alanate from alkali hydride, Al and hydrogen, was hampering reversibility. The reverse reaction was then studied for the same phase diagram, starting with LiH, NaH, and MgH2, and Al. The study was extended to phase diagrams including KH and CaH2 as well. The observed hydrogen storage capacity in the Al hexahydrides was less than 4 wt. %, well short of DOE targets. The HT assay came on line and after certification with studies on NaAlH4, was first applied to the LiNH2 - LiBH4 - MgH2 phase diagram. The 60-point study elucidated trends within the system locating an optimum material of 0.6 LiNH2 - 0.3 MgH2 - 0.1 LiBH4 that stored about 4 wt. % H2 reversibly and operated below 220 °C. Also present was the phase Li4(NH2)3BH4, which had been discovered in the LiNH2 -LiBH4 system. This new ternary formulation performed much better than the well-known 2 LiNH2 - MgH2 system by 50 °C in the HT assay. The Li4(NH2)3BH4 is a low melting ionic liquid under our test conditions and facilitates the phase transformations required in the hydrogen storage reaction, which no longer relies on a higher energy solid state reaction pathway. Further study showed that the 0.6 LiNH2 - 0.3 MgH2 - 0.1 LiBH4 formulation was very stable with respect to ammonia and diborane desorption, the observed desorption was from hydrogen. This result could not have been anticipated and was made possible by the efficiency of HT combinatorial methods. Investigation of the analogous LiNH2 - LiBH4 - CaH2 phase diagram revealed new reversible hydrogen storage materials 0.625 LiBH4 + 0.375 CaH2 and 0.375 LiNH2 + 0.25 LiBH4 + 0.375 CaH2 operating at 1 wt. % reversible hydrogen below 175 °C. Powder x-ray diffraction revealed a new structure for the spent materials which had not been previously observed. While the storage capacity was not impressive, an important aspect is that it boron appears to participate in a low temperature reversible reaction. The last major area of study also focused on activating boron-based materials in order to exploit the tremendous gravimetric capacity of LiBH4. A number of LiNH2 - LiBH4 - transition metal (TM) systems were investigated for the following reasons. No additional leads were discovered in this system. Another major project activity was the assembly of a high throughput synthesis system. The automated synthesizer was set up in a glovebox and was capable of handling liquids and powders and carrying out sealed block syntheses up to 250 °C. Unfortunately, the synthesizer could not handle the delivery of the fine powders required fro hydrogen storage applications. Although the powder delivery system was overhauled and redesigned several times, this problem was never remedied.

Download or read book Heat Transfer and Fluid Flow written by James M. Jacobs and published by . This book was released on 1958 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt: A total of 2519 annotated references to the unclassified report literature is presented. Subjects covered under heat transfer and fluid flow include radioinduced heating; boiling; boiler, evaporators, pump, and heat exchanger design; hydrodynamics; coolants and their properties; thermal and flow instrumentation; high temperature materials; thermal properties of materials; and thermal insulation. Subjects covered less completely include thermodynamics; aerodynamics; high temperature corrosion; corrosion specific to heat transfer systems; erosion; mass transfer; corrosion film formation and effects; coolant processing and radioactivity; radiation effects of heat transfer materials; and pertinent data of thermonuclear processes. Subject, report number availability, and author indexes are given.