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Recovery of nitric acid from raffinate and condensate solutions by steam distillation/pyrohydrolysis and fractional distillation in a glass column

Description: Potential processes for the pilot-plant-scale purification and concentration of nitric acid condensate and raffinate solutions were studied. As a result, a process was developed where condensates were continuously purified by an aluminum nitratecalcium nitrate trap to reduce 200 to 300-ppM fluoride concentrations to <1 ppM. Next, the condensates were fed to an all-glass rectification column to concentrate nitric acid to 14 molar and to reduce 200 10 400-ppM chloride concentrations to <1 ppM. Finally, raffinates were steam distilled and pyrohydrolyzed to recover >90% of the nitrates as nitric acid. (auth)
Date: December 28, 1973
Creator: Dietrich, W.C.

Production Scale-Up or Activated Carbons for Ultracapacitors

Description: Transportation use accounts for 67% of the petroleum consumption in the US. Electric and hybrid vehicles are promising technologies for decreasing our dependence on petroleum, and this is the objective of the FreedomCAR & Vehicle Technologies Program. Inexpensive and efficient energy storage devices are needed for electric and hybrid vehicle to be economically viable, and ultracapacitors are a leading energy storage technology being investigated by the FreedomCAR program. The most important parameter in determining the power and energy density of a carbon-based ultracapacitor is the amount of surface area accessible to the electrolyte, which is primarily determined by the pore size distribution. The major problems with current carbons are that their pore size distribution is not optimized for liquid electrolytes and the best carbons are very expensive. TDA Research, Inc. (TDA) has developed methods to prepare porous carbons with tunable pore size distributions from inexpensive carbohydrate based precursors. The use of low-cost feedstocks and processing steps greatly lowers the production costs. During this project with the assistance of Maxwell Technologies, we found that an impurity was limiting the performance of our carbon and the major impurity found was sulfur. A new carbon with low sulfur content was made and found that the performance of the carbon was greatly improved. We also scaled-up the process to pre-production levels and we are currently able to produce 0.25 tons/year of activated carbon. We could easily double this amount by purchasing a second rotary kiln. More importantly, we are working with MeadWestvaco on a Joint Development Agreement to scale-up the process to produce hundreds of tons of high quality, inexpensive carbon per year based on our processes.
Date: January 10, 2007
Creator: Dietz, Dr. Steven D.

SRE Mark II Fuel Handling Machine

Description: Abstract: The Sodium Reactor Experiment Mark II Fuel Handling Machine has been modified to ensure fuel and gas containment during core III operation. A new fuel control system has been designed for the fuel handling machine.
Date: April 20, 1965
Creator: Dietz, H. B.

Recent advances in the development of extraction chromatographic materials for the isolation of radionuclides from biological and environmental samples.

Description: The determination of low levels of radionuclides in environmental and biological samples is often hampered by the complex and variable nature of the samples. One approach to circumventing this problem is to incorporate into the analytical scheme a separation and preconcentration step by which the species of interest can be isolated from the major constituents of the sample. Extraction chromatography (EXC), a form of liquid chromatography in which the stationary phase comprises an extractant or a solution of an extractant in an appropriate diluent coated onto an inert support, provides a simple and efficient means of performing a wide variety of metal ion separations. Recent advances in extractant design, in particular the development of extractants capable of metal ion recognition or of strong complex formation even in acidic media, have substantially improved the utility of the method. For the preconcentration of actinides, for example, an EXC resin consisting of a liquid diphosphonic acid supported on a polymeric substrate has been shown to exhibit extraordinarily strong retention of these elements from acidic chloride media. This resin, together with other related materials, can provide the basis of a number of efficient and flexible schemes for the separation and preconcentration of radionuclides form a variety of samples for subsequent determination.
Date: November 30, 1998
Creator: Dietz, M. L.

Supercritical carbon dioxide-soluble ligands for extracting actinide metal ions from porous solids (EMSP Project Number 64965)

Description: The objective of this project is to develop novel, substituted diphosphonic acid ligands that can be used for supercritical carbon dioxide extraction (SCDE) of actinide ions from solid wastes. Specifically, selected diphosphonic acids, which are known to form extremely stable complexes with actinides in aqueous and organic solution, are to be rendered carbon dioxide-soluble by the introduction of appropriate alkyl- or silicon-containing substituents. The metal complexation chemistry of these new ligands in SC-CO{sub 2} will then be investigated and techniques for their use in actinide extraction from porous solids developed. This report summarizes the work performed during the first 1.3 years of a 3-year program. Because the planned studies of metal complexation and the development of techniques for actinide removal from solids are dependent on the availability of suitable ligands, efforts to date have focused primarily on the synthesis of selected alkyl- or silicon-containing diphosphonic acids. The authors' principal targets have been derivatives in which the silicon-containing groups either serve as the ester function or are attached to the anchor carbon of the diphosphonic acid. Because methylenediphosphonic acid (MDPA) is commercially available and because its esterification with simple alcohols to yield symmetrical diesters is well-established, their initial studies have focused on this ligand and its reactions with silyl alcohols. Success has been achieved in the reaction of MDPA and its ethylene, propylene, and butylene analogs with 3-(trimethylsilyl)-1-propanol. Using a procedure similar to that previously employed for the synthesis of C-8 dialkylmethylenediphosphonic acids, this series of alkylenediphosphonic acids has been esterified in good yield (ca. 60%) to the symmetrically-substituted diesters. Vapor phase osmometric and cryoscopic studies of these compounds in toluene and 1-decanol, respectively, indicate that their aggregation properties closely parallel those of the dialkyl-substituted alkylenediphosphonic acids, specifically, the P,P{prime}-bis(2-ethylhexyl)alkylenediphosphonic acids, H{sub 2}DEH[ADP]. Infrared spectroscopy and molecular mechanics methods have been ...
Date: April 24, 2000
Creator: Dietz, M. L.; Barrans, Jr., R. E.; Herlinger, A. W. & Brennecke, J. F.

Extraction chromatography: Progress and opportunities

Description: Extraction chromatography provides a simple and effective method for the analytical and preparative-scale separation of a variety of metal ions. Recent advances in extractant design, particularly the development of extractants capable of metal ion recognition or of strong complex formation in highly acidic media, have significantly improved the utility of the technique. Advances in support design, most notably the introduction of functionalized supports to enhance metal ion retention, promise to yield further improvements. Column instability remains a significant obstacle, however, to the process-scale application of extraction chromatography. 79 refs.
Date: October 1, 1997
Creator: Dietz, M.L.; Horwitz, E.P. & Bond, A.H.

Supercritical Carbon Dioxide-Soluble Ligands for Extracting Actinide Metal Ions from Porous Solids

Description: Numerous types of actinide-bearing waste materials are found throughout the DOE complex. Most of these wastes consist of large volumes of non-hazardous materials contaminated with relatively small quantities of actinide elements. Separation of these wastes into their inert and radioactive components would dramatically reduce the costs of stabilization and disposal. For example, the DOE is responsible for decontaminating concrete within 7000 surplus contaminated buildings. The best technology now available for removing surface contamination from concrete involves removing the surface layer by grit blasting, which produces a large volume of blasting residue containing a small amount of radioactive material. Disposal of this residue is expensive because of its large volume and fine particulate nature. Considerable cost savings would result from separation of the radioactive constituents and stabilization of the concrete dust. Similarly, gas diffusion plants for uranium enrichment contain valuable high-purity nickel in the form of diffusion barriers. Decontamination is complicated by the extremely fine pores in these barriers, which are not readily accessible by most cleaning techniques. A cost-effective method for the removal of radioactive contaminants would release this valuable material for salvage. The objective of this project is to develop novel, substituted diphosphonic acid ligands that can be used for supercritical carbon dioxide extraction of actinide ions from solid wastes. Specifically, selected diphosphonic acids, which are known to form extremely stable complexes with actinides in aqueous and organic solution, are to be rendered carbon dioxide-soluble by the introduction of appropriate alkyl- or silicon-containing substituents. The metal complexation chemistry of these new ligands in SC-CO2 will then be investigated and techniques for their use in actinide extraction from porous solids developed.
Date: June 1, 2001
Creator: Dietz, Mark L.

Supercritical Carbon Dioxide-Soluble Ligands for Extracting Actinide Metal Ions from Porous Solids

Description: The focus of the effort during the project period from 9/16/98 to 6/15/99 has been on the synthesis, aggregation, and coordination chemistry of silyl-containing diphosphonic acids that potentially could be useful as solvent extraction reagents in supercritical CO2. A homologous series of alkylenediphosphonic acids was esterified with 3-(trimethylsilyl)-1- propanol to the symmetrically-substituted diesters. The silicon-containing alcohol 3- (trimethylsilyl)-1-propanol was chosen for esterification of the diphosphonic acids because it contains both a silyl group and a trimethylene linker. Separating the trimethylsilyl from the organo-functional group by three carbon atoms is optimal for achieving chemical stability and synthetic accessibility. The synthesis of these compounds utilizes methodology that relies on dicyclohexylcarbodiimide as the esterification reagent to activate the acid.
Date: June 1, 1999
Creator: Dietz, Mark L.; Barrans Jr., Richard E.; Herlinger, Albert & Brennecke, Joan F.

Transmission electron microscopy analysis of corroded metal waste forms.

Description: This report documents the results of analyses with transmission electron microscopy (TEM) combined with energy dispersive X-ray spectroscopy (EDS) and selected area electron diffraction (ED) of samples of metallic waste form (MWF) materials that had been subjected to various corrosion tests. The objective of the TEM analyses was to characterize the composition and microstructure of surface alteration products which, when combined with other test results, can be used to determine the matrix corrosion mechanism. The examination of test samples generated over several years has resulted in refinements to the TEM sample preparation methods developed to preserve the orientation of surface alteration layers and the underlying base metal. The preservation of microstructural spatial relationships provides valuable insight for determining the matrix corrosion mechanism and for developing models to calculate radionuclide release in repository performance models. The TEM results presented in this report show that oxide layers are formed over the exposed steel and intermetallic phases of the MWF during corrosion in aqueous solutions and humid air at elevated temperatures. An amorphous non-stoichiometric ZrO{sub 2} layer forms at the exposed surfaces of the intermetallic phases, and several nonstoichiometric Fe-O layers form over the steel phases in the MWF. These oxide layers adhere strongly to the underlying metal, and may be overlain by one or more crystalline Fe-O phases that probably precipitated from solution. The layer compositions are consistent with a corrosion mechanism of oxidative dissolution of the steel and intermetallic phases. The layers formed on the steel and intermetallic phases form a continuous layer over the exposed waste form, although vertical splits in the layer and corrosion in pits and crevices were seen in some samples. Additional tests and analyses are needed to verify that these layers passivate the underlying metals and if passivation can break down as the MWF corrodes. The ...
Date: April 15, 2005
Creator: Dietz, N. L.


Description: The perfluorocarbon tracer (PFT) technology can be applied simultaneously to the wide range in zonal flowrates (from tens of cfms in some Control Rooms to almost 1,000,000 cfm in Turbine Buildings), to achieve the necessary uniform tagging for subsequent determination of the desired air inleakage and outleakage from all zones surrounding a plant's Control Room (CR). New types of PFT sources (Mega sources) were devised and tested to handle the unusually large flowrates in a number of HVAC zones in power stations. A review of the plans of a particular nuclear power plant and subsequent simulations of the tagging and sampling results confirm that the technology can provide the necessary concentration measurement data to allow the important ventilation pathways involving the Control Room and its air flow communications with all adjacent zones to be quantitatively determined with minimal uncertainty. Depending on need, a simple single or 3-zone scheme (involving the Control Room alone or along with the Aux. Bldg. and Turbine Bldg.) or a more complex test involving up to 7 zones simultaneously can be accommodated with the current revisions to the technology; to test all the possible flow pathways, several different combinations of up to 7 zones would need to be run. The potential exists that for an appropriate investment, in about 2 years, it would be possible to completely evaluate an entire power plant in a single extended multizone test with up to 12 to 13 separate HVAC zones. With multiple samplers in the Control Room near each of the contiguous zones, not only will the prevalent inleakage or outleakage zones be documented, but the particular location of the pathway's room of ingress can be identified. The suggested protocol is to perform a 3-zone test involving the Control Room, Aux. Bldg., and Turbine Bldg. to (1) verify CR ...
Date: January 1, 2002
Creator: Dietz, R. N.

Pacer processing: cavity inventory relationships

Description: The pacer cavity and its associated primary power loop comprise a recirculating system in which materials are introduced by a series of thermonuclear explosions while debris is continuously removed by radioactive decay, sorption phenomena, and deliberate processing. Safe, reliable, and economical realization of the Pacer concept depends on the removal and control of both noxious and valuable by-products of the fusion reaction. Mathematical relationships are developed that describe the quantities of materials that are introduced into the Pacer cavity by a series of discrete events and are removed continuously by processing and decay. An iterative computer program based on these relationships is developed that allows both the total cavity inventory and the amounts of important individual species to be determined at any time during the lifetime of the cavity in order to establish the effects of the thermonuclear event, the cavity, the flow, and various processing parameters on Pacer design requirements. (auth)
Date: September 1, 1975
Creator: Dietz, R.J. & Gritzo, L.A.

Vapor detection of trafficking of contraband money: A discussion of technical feasibility

Description: For every two pounds of cocaine smuggled into the US, drug traffikers are being forced to clandestinely ship three pounds of money back out for subsequent laundering. Based on tracer technology developed for validation of long-range atmospheric transport models and other commercial applications, it is shown that US currency can be tagged with a minute amount (about 1 ppm by weight of a bill) of perfluorocharbon tracer (PFT) material that is sufficient to last for about 30 years and yet provide a vapor emission rate suitable for detectability of modest caches of contraband money in vehicles at border crossings, on aircraft at international terminals, and in buildings. The cost of tagging is less than $5 per million bills; the taggant quantity should have no impact on the feel of a bill. The low emission rate would not allow detectability of usual amounts of money in typical scenarios, providing an essential degree of privacy, but extraordinary amounts would be detectable using specialized instrumentation and know-how not easily attainable but commercially in production; an example of sub-part-per-quadrillion detection of a proposed PFT taggant is demonstrated using a prototype commercial unit. An outline of a research and demonstration program to achieve this capability and details of the proposed tagging and detection procedures already indicate that the concept is technically feasible.
Date: February 1, 1996
Creator: Dietz, R.N.

Measurement of HVAC system performance and local ventilation using passive perfluorocarbon tracer technology

Description: In April of 1993, two (2) perfluorocarbon tracer (PFT) ventilation/indoor air quality assessment tests were performed in the Gleeson Hall building of the SUNY Farmingdale campus. The building was being modified, in part, as a result of significant occupant complaints of perceived poor air quality. The four story building had a basement first floor with air supplied normally by an HVAC system labelled as AC1. During this study, AC1 was inoperational and the basement interior rooms (walls) were primarily gone; the other three floors were still being used for classes. It is possible that a sense of poor air quality may have been perceived by first-floor occupants because they were working in the basement, but this issue could not be addressed. The second floor had two (2) lecture halls--Rm 202 (handled by AC4) and Rm 204 (handled by AC5); the balance of the second floor interior rooms and corridors was split between two other air handling systems, AC2 for the west side of the building and AC3 for the east side. The remaining 3rd and 4th floors were also split about evenly between AC2 and AC3. The perimeter rooms, equipped with wall units having their own outside air (OA) source plus centralized return air (RA) bypasses, were not included in this testing which was restricted to the basement floor (1st floor) and the four operating air handling systems, AC2 to AC5, during Test 1 and only AC2 to AC5 during Test 2. Two types of tests were performed using the full suite of 5 PFT types available. The first test was designed to measure the infiltration, exfiltration, and air exchange between the 5 AC zones above and the second test used the 5th tracer, which had been in the basement, as a distributed source throughout the four other zones to ...
Date: June 1, 1995
Creator: Dietz, R.N. & Goodrich, R.W.

Detection of interstate liquids pipeline leaks: Feasibility evaluation

Description: The approximately 200,000-mile fuel pipeline system in the US operates at flow rates up to 2.5 {times} 10{sup 6} gallons per hour (GPH). Most commercial technologies only provide on-line leak detection at about 0.3% of flow rate, i.e., about 7,500 GPH or larger. Detection of leaks at about 1 GPH or so is desirable both from a regulatory and leak-prevention standpoint. Brookhaven`s commercially-accepted perfluorocarbon tracer (PFT) technology for underground leak detection of utility industry dielectric fluids at leak rates less than 0.1 GPH, with new enhancements, will be able to cost-effectively detect fuel pipeline system leaks to about 1 GPH--3 orders-of-magnitude better than any on-line system. The magnitude of detected leaks would be calculable as well. Proposed mobile surveys (such as those used periodically in the gas pipeline industry) at about 110 to 120 miles per day would allow such small leaks to be detected at 10-ppb tagging levels (less than $1,500 of PFT for a 48-hour tag at the maximum transport rate) under worst-case meteorological dispersion conditions. Smaller leaks could be detected by proportionately larger tagging concentrations. Leaks would be pinpointed by subsequent conventional barholing and vapor analyses. There are no health nor safety issues associated with the use of the proposed technological approach nor any consequential environmental impacts associated with the proposed magnitudes of PFT tagging.
Date: October 20, 1998
Creator: Dietz, R.N. & Senum, G.I.