Srnl Unique Porous Wall, Hollow Glass Microspheres (pw-hgms) for Hydrogen Storage, Separations and Other Applications

Content Provider	Semantic Scholar
Author	Wicks, George G. Heung, L. Kit Schumacher, R. F.
Copyright Year	2008
Abstract	The Savannah River National Laboratory (SRNL) has developed a new medium for storage of hydrogen and other gases. This involves fabrication of thin, Porous Walled, Hollow Glass Microspheres (PW-HGMs), with diameters generally in the range of 1 to several hundred microns. What is unique about the glass microballons is that porosity has been induced and controlled within the thin, one micron thick walls, on the scale of 10 to several thousand Angstroms. This porosity results in interesting properties including the ability to use these channels to fill the microballons with special absorbents and other materials, thus providing a contained environment even for reactive species. Gases can now enter the microspheres and be retained on the absorbents, resulting in solid-state and contained storage of even reactive species. Also, the porosity can be altered and controlled in various ways, and even used to filter mixed gas streams within a system. SRNL is involved in about a half dozen different programs involving these PW-HGMs and an overview of some of these activities and results emerging are presented. INTRODUCTION The Savannah River Site (SRS) and its Laboratory (SRNL), located in Aiken, South Carolina, have had a long and successful history of working with hydrogen and its isotopes for national security, energy and waste management/ environmental remediation applications. This includes more than 40 years of experience in handling and processing tritium/ deuterium/ hydrogen and more than 30 years of experience developing, processing and implementing special ceramics, including glasses, for a variety of Department of Energy (DOE) missions. In the case of glasses, the site has been involved in both the science and engineering of vitreous or glass-based systems, especially in the waste management field. This includes developing 40-component SRS nuclear waste glass systems, with the technical ability to incorporate and immobilize high level radioactive (HLW) wastes into inert and safe products. In addition to the science involved in these programs, the engineering aspects have also been developed and demonstrated, as exemplified by one of the most unique, vitrification or glass making plants in the world, called the Defense Waste Processing Facility, or DWPF. This is a more than one billion dollar facility built at the SRS site, that is currently in production, immobilizing the 34 million gallons of radioactive SRS HLW stored on site, into complex borosilicate glass forms, producing waste glass products in canisters that are 2-ft. in diameter, and almost 10-ft. high. The DWPF began operations in 1996 and has run almost continuously since then producing more than 2000 canisters or 4,000 tons of glass immobilizing more than 10 million curies of radioactivity. As a part of this glass experience and expertise, SRNL has also developed a number of niches in the glass arena, one of which is the development of porous glass systems for a variety of applications. These porous glass systems include sol gel glasses, which include both xerogels as well as aerogels, as well as phase separated glass compositions, that can be subsequently treated to produce another unique type of porosity within the glass forms. The porous glasses can increase the surface area compared to ‘normal glasses’, of 1 to 2 orders of magnitude, which can result in unique properties in areas such as hydrogen storage, gas transport, gas separations and purification, sensors, global warming applications, new drug delivery systems, etc.. One of the most interesting porous glass products that SRNL has developed and patented is Porous Wall, Hollow Glass Microspheres (PW-HGMs), that are being studied for many different
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Alternate Webpage(s)	https://sti.srs.gov/fulltext/WSRC-STI-2007-00563.pdf
Language	English
Access Restriction	Open
Content Type	Text
Resource Type	Article