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Uranium Peroxide

Description: It was desired to investigate the precipitation of UO{sub 4} in acid solution, in order to determine the suitability of this reaction for use in the purification of uranium. A series of tests was performed to establish the conditions for precipitation of UO{sub 4}. It was found that uranium could be completely precipitated from pure uranyl sulfate solution at a pH of 2.5 to 3.5, with only silght excess of H{sub 2}O{sub 2}. The presence of sodium sulfate interferred with complete precipitation. It was established that vanadium was preferentially oxidized, when present.
Date: April 14, 1947
Creator: Brimm, E. O., Dr. & Nohr, P.
Partner: UNT Libraries Government Documents Department

Determination of labile copper, cobalt, and chromium in textile mill wastewater

Description: Copper, chromium, and cobalt species present in filtered wastewater effluent were separated by cation exchange and reverse phase chromatography. Three sample fractions were obtained: one containing metal cations (i.e., trivalent Cr, divalent Cu, and divalent Co), one containing organic species (including metallized dyes), and one containing other unretained species. The metal content of each fraction was determined by inductively coupled plasma atomic emission spectroscopy (ICP-AES). The sum of the corrected data was compared to the metal content of a filtered effluent aliquot digested totally with fuming sulfuric acid. Other aliquots of the filtered effluent were spiked with the metals of interest and digested to confirm chemical yield and accuracy. Method detection limits were consistently below 20 {mu}g L{sup -1} for Cu, 30 {mu}g L{sup -1} for Co, and 10 {mu}g L{sup -1} for Cr. Spike recoveries for undifferentiated Cu and Cr were statistically indistinguishable from unity; although Co spike recoveries were slightly low ({approximately}95%), its chemical yield was 98%. Copper retention on the sodium sulfonate cation exchange resin was closely correlated with the [EDTA]/[Cu] ratio, suggesting that metals retained upon the cation exchange column were assignable to labile metal species; however, mass balances for all three elements, though reasonable ({approximately}90%), were significantly different from unity. Mechanical factors may have contributed to the material loss, but other data suggest that some metal species reacted irreversibly with the reverse phase column. 3 refs., 2 figs., 4 tabs.
Date: January 1, 1997
Creator: Crain, J.S.; Essling, A.M. & Kiely, J.T.
Partner: UNT Libraries Government Documents Department

Electrochemical decontamination system for actinide processing gloveboxes

Description: An electrolytic decontamination technology has been developed and successfully demonstrated at Los Alamos National Laboratory (LANL) for the decontamination of actinide processing gloveboxes. The technique decontaminates the interior surfaces of stainless steel gloveboxes utilizing a process similar to electropolishing. The decontamination device is compact and transportable allowing it to be placed entirely within the glovebox line. In this way, decontamination does not require the operator to wear any additional personal protective equipment and there is no need for additional air handling or containment systems. Decontamination prior to glovebox decommissioning reduces the potential for worker exposure and environmental releases during the decommissioning, transport, and size reduction procedures which follow. The goal of this effort is to reduce contamination levels of alpha emitting nuclides for a resultant reduction in waste level category from High Level Transuranic (TRU) to low Specific Activity (LSA, less than or equal 100 nCi/g). This reduction in category results in a 95% reduction in disposal and disposition costs for the decontaminated gloveboxes. The resulting contamination levels following decontamination by this method are generally five orders of magnitude below the LSA specification. Additionally, the sodium sulfate based electrolyte utilized in the process is fully recyclable which results in the minimum of secondary waste. The process bas been implemented on seven gloveboxes within LANL`s Plutonium Facility at Technical Area 55. Of these gloveboxes, two have been discarded as low level waste items and the remaining five have been reused.
Date: March 1, 1998
Creator: Wedman, D.E.; Lugo, J.L.; Ford, D.K.; Nelson, T.O.; Trujillo, V.L. & Martinez, H.E.
Partner: UNT Libraries Government Documents Department

Estimating the hydrogen ion concentration in concentrated NaCl and Na{sub 2}SO{sub 4} electrolytes

Description: Combination glass electrodes were tested for determining H{sup +} concentrations in concentrated pure and mixed NaCl and Na{sub 2}SO{sub 4} solutions, as well as natural brine systems. NaCl, Na{sub 2}SO{sub 4}, and mixtures of NaCl and Na{sub 2}SO{sub 4} solutions were analyzed. Correction factors for estimating pC{sub H}{sup +} (negative logarithm of H{sup +} concentration) were determined from measured/observed pH values. Required Gran-type titrations were done with HCl and/or NaOH. The titration method is described and a step-by-step procedure provided; it has been used previously for determining pC{sub H}{sup +} values of synthetic chloride-dominated brines. Precautions are required to determine correction factors for electrolytes that react with H{sup +} or OH{sup {minus}} [sulfate brines for titration with acid; magnesium brines for titration with base because of precipitation of Mg(OH)2]. Correction factors A (pC{sub H}{sup +} = pH{sub ob} + A) from HCl titrations were similar to those from NaOH titrations where the concentration of free H{sup +} was calculated using a thermodynamic model. These values should be applicable to solns with a very large range in measured pH values (2 to 12). Because a large number of solns were titrated with HCl and the A values are similar for HCl and NaOH titrations, the A values for NaCl and Na2SO4 solns were fit as a function of molality to allow extrapolation. For NaCl solns 0 to 6.0 M, A can be obtained by multiplying the molality by 0.159. For Na2SO4 solns 0 to 2.0 M, the values of A can be obtained from (0.221 {minus} 0.549X + 0.201X{sup 2}), where X is the molality of Na{sub 2}SO{sub 4}. Orion-Ross electrode evaluations indicated that the A values did not differ significantly for different electrodes. Results suggest that the data in this report can be used to estimate A values for different ...
Date: June 1, 1995
Creator: Rai, D.; Felmy, A.R.; Juracich, S.P. & Rao, F.
Partner: UNT Libraries Government Documents Department

Hot Corrosion of Nickel-Base Alloys in Biomass-Derived Fuel Simulated Atmosphere

Description: Biomass fuels are considered to be a promising renewable source of energy. However, impurities present in the fuel may cause corrosion problems with the materials used in the hot sections of gas turbines and only limited data are available so far. As part of the Advanced Turbine Systems Program initiated by the U.S. Department of Energy, the present study provides initial data on the hot corrosion resistance of different nickel-base alloys against sodium sulfate-induced corrosion as a baseline, and against salt compositions simulating biomass-derived fuel deposits. Single crystal nickel-superalloy Rene N5, a cast NiCrAlY alloy, a NiCoCrAlY alloy representing industrially used overlay compositions, and a model {beta}NiAl+Hf alloy were tested in 1h thermal cycles at 950 C with different salt coatings deposited onto the surfaces. Whereas the NiCoCrAlY alloy exhibited reasonable resistance against pure sodium sulfate deposits, the NiCrAiY alloy and Rene N5 were attacked severely. Although considered to be an ideal alumina former in air and oxygen at higher temperatures, {beta}NiAl+Hf also suffered from rapid corrosion attack at 950 C when coated with sodium sulfate. The higher level of potassium present in biomass fuels compared with conventional fuels was addressed by testing a NiCoCrAlY alloy coated with salts of different K/Na atomic ratios. Starting at zero Na, the corrosion rate increased considerably when sodium was added to potassium sulfate. In an intermediate region the corrosion rate was initially insensitive to the K/Na ratio but accelerated when very Na-rich compositions were deposited. The key driver for corrosion of the NiCoCrAlY alloy was sodium sulfate rather than potassium sulfate, and no simple additive or synergistic effect of combining sodium and potassium was found.
Date: February 28, 1999
Creator: Leyens, C.; Pint, B.A. & Wright, I.G.
Partner: UNT Libraries Government Documents Department


Description: The line width of one of the hynerfine components in solutions of Mn(ClO/ sub 4/)/sub 2/ containing added NaCl and Na/sub 2/SO/sub 4/ was studied from 20 to 200 deg C at 9000 Mc/sec. The chloride ion contributes littie broadening at 0.1 M below 80 deg C but considerable broadening is obtained above this temperature. The sulfate contributes broadening at all temperatures. The rates of formation of inner-sphere'' and outersphere'' complexes are discussed together with their rates of relaxation. At the lower temperatures the outersphere'' complexes primarily contribute to the broadening while at the higher temperatures the inner-sphere'' complexes also contribute. From the broadening above 80%DEC the rates of formation of the inner-sphere'' complexes are evaluated. (auth)
Date: September 23, 1963
Creator: Hayes, R.G. & Myers, R.J.
Partner: UNT Libraries Government Documents Department

Mineral-Surfactant Interaction for Minimum Reagents Precipitation and Adsorption for Improved Oil Recovery

Description: In this project, fundamental studies were conducted to understand the mechanisms of the interactions between polymers/surfactants and minerals with the aim of minimizing chemical loss by adsorption. The effects of structures of the surface active molecules on critical solid/liquid interfacial properties such as adsorption, wettability and surface tension in mineral/surfactant systems were investigated. The final aim is to build a guideline to design optimal polymer/surfactant formula based on the understanding of adsorption and orientation of surfactants and their aggregates at solid/liquid interfaces. During this period, the wettability of alumina was tested using two-phase extraction at different pHs. The results were explained using the adsorption data obtain previously. It was found that the wettability is determined by both the nano-structure of the hemimicelles and the surface coverage. It was found that pH plays a critical role in controlling the total adsorption and the mineral wettability. At pH 4, the alumina surface remains hydrophilic in the surfactant concentration range tested because of the low surface coverage, even though hemimicelles are formed. Adsorption of sodium dodecyl sulfate (SDS) on alumina and silica, the component minerals reservoir rocks, was conducted at different pHs. The adsorption of SDS on silica is negligible, while the adsorption on alumina is high due to the different charge of the latter. Tests of adsorption of a modified polymer S-19703-35HT on alumina were also conducted at different pHs. Adsorption density decreases with pH. The results suggest that alkaline pH range is more cost-effective for a SDS/polymer system because of the low adsorption density. A new term, reagent loss index (RLI), was used to analyze the adsorption data for different surfactants and minerals. It was shown that the chemical loss is very high in the case of SDS on gypsum and limestone, while it is low in the case of silica. ...
Date: September 30, 2006
Creator: Somasundaran, P.
Partner: UNT Libraries Government Documents Department

Gas evolution during vitrification of sodium sulfate and silica

Description: This paper describes the operation of an apparatus designed to identify species evolved during vitrification of hazardous waste materials and to measure the temperatures at which they are evolved. To demonstrate the utility of the apparatus for designing off-gas systems, the authors present the results of heating various sulfates alone and in the presence of silica. During vitrification, the decomposition behavior of some waste components will be affected by the chemical composition of the melt. For example, they found that when silica is present during heating, SO{sub x} gases are evolved at lower temperatures than when pure sodium sulfate is heated. Such analyses will be important in the design of off-gas units for waste vitrification systems.
Date: August 1, 1997
Creator: Ebert, W.L.; Bakel, A.J. & Rosine, S.D.
Partner: UNT Libraries Government Documents Department

Corrosion performance of materials for advanced combustion systems

Description: Conceptual designs of advanced combustion systems that utilize coal as a feedstock require high-temperature furnaces and heat transfer surfaces capable of operating at much higher temperatures than those in current coal-fired power plants. The combination of elevated temperatures and hostile combustion environments requires development and application of advanced ceramic materials for heat exchangers in these designs. This paper characterizes the chemistry of coal-fired combustion environments over the wide temperature range of interest in these systems and discusses some of the experimental results for several materials obtained from laboratory tests and from exposures in a pilot-scale facility.
Date: May 1995
Creator: Natesan, K.; Freeman, M. & Mathur, M.
Partner: UNT Libraries Government Documents Department

Significance of Experimental Procedures on the Hot Corrosion Behavior of Nickel-Base Alloys Under Cyclic Conditions

Description: A simplified test procedure was established to assess the hot corrosion behavior of MCrAlY-type nickel-base alloys under the influence of molten sodium sulfate as well as sodium sulfate/potassium sulfate salt mixtures. Salt coated specimens were exposed to lh thermal cycles at 950°C in flowing oxygen for up to 500 cycles. Mass change data of the specimens revealed a significant dependence of the corrosion attack not only, as expected, on the average contaminant flux rate, but also on the initial amount of salt deposited during each recoating cycle. Furthermore, deposit removal before salt recoating was found to markedly influence the corrosion attack of the alloys. This was related to changes in salt chemistry by the dissolution of elements such as Cr from the alloy which shifted the basicity of the salt and thus affected the extent of attack. Substituting Na for K in sodium sulfate/potassium sulfate salt mixtures enerally resulted in a decreased attack. Although the high K-containing salts still caused significant attack typical of Type-I hot corrosion, the overall degration was much less than for sodium sulfate alone.
Date: February 25, 1999
Creator: Leyens, C.; Pint, B.A.; Tortorelli, P.F. & Wright, I.G.
Partner: UNT Libraries Government Documents Department

Halogen Collector Test Program

Description: Efficiency tests of removal of radioactive iodine from an air stream were performed on the following halogen collectors: a silver-plated copper-ribbon bed: activatedcharcoal beds, 0.5 and l.0 in. deep: a molecular-sieve bed; and a sodium thiosulfate bed. The tests were conducted at 70 and 160 deg F and at 70 and 95% relative humidity. Only the activated-charcoal collectors achieved a high iodineremoval efficiency over a sustained period at the various operating conditions. (C.J.G.)
Date: March 1, 1960
Partner: UNT Libraries Government Documents Department

Chemical vapor deposition of Ta{sub 2}O{sub 5} corrosion resistant coatings

Description: Silicon carbide and silicon nitride heat engine components are susceptible to hot corrosion by molten Na{sub 2}SO{sub 4} which forms from impurities present in fuel and the environment. Chemically vapor deposited Ta{sub 2}O{sub 5} coatings are being developed as a means to protect components from reaction with these salts and preserve their structural properties. Investigations to optimize the structure of the coating have revealed that the deposition conditions dramatically affect the coating morphology. Coatings deposited at high temperatures are typically columnar in structure; high concentrations of the reactant gases produce oxide powders on the substrate surface. Ta{sub 2}O{sub 5} deposited at low temperatures consists of grains that are finer and have significantly less porosity than that formed at high temperatures. Samples of coatings which have been produced by CVD have successfully completed preliminary testing for resistance to corrosion by Na{sub 2}SO{sub 4}.
Date: December 31, 1992
Creator: Graham, D. W. & Stinton, D. P.
Partner: UNT Libraries Government Documents Department

Aerosol phase transformation in the atmosphere

Description: Ambient aerosols are frequently composed of hygroscopic inorganic salts such as chlorides, sulfates and nitrates in either pure or mixed forms. Such inorganic salt aerosols exhibit the properties of deliquescence and efflorescence in air. The phase transformation from a solid particle to a saline droplet usually occurs spontaneously when atmospheric relative humidity reaches a level specific to the chemical composition of the aerosol particle. Conversely, when relative humidity decreases and becomes low enough, a saline droplet will evaporate and suddenly crystallize, expelling all its water content. Information on the composition and temperature dependence of these properties is required in mathematical models for describing the dynamic and transport behavior of ambient aerosols. Experiments are carried out in the temperature range 5--35{degrees}C, using single particles individually suspended in an electrodynamic cell that can be evacuated and back filled with water vapor. The phase transformation of the aerosol particle is monitored by laser light scattering and the relative humidity at the transition point is determined by directly measuring the water vapor pressure in the cell. Results are obtained for particles containing either a single salt or a preselected mixture of NaCl, KCl, NaNO{sub 3}, Na{sub 2}SO{sub 4} and (NH{sub 4}){sub 2}SO{sub 4}, which are common constituents of ambient aerosols. A theoretical model on the composition and temperature dependence of the deliquescence properties is developed for single and two-salt aerosol systems.
Date: September 1, 1992
Creator: Tang, I. N. & Munkelwitz, H. R.
Partner: UNT Libraries Government Documents Department


Description: The purpose of this report is to present and assess water activity versus ionic strength for six solutes:sodium nitrate, sodium nitrite, sodium chloride, sodium carbonate, sodium sulfate, and potassium nitrate. Water activity is given versus molality (e.g., ionic strength) and temperature. Water activity is used to estimate Hanford crystal hydrate solubility present in the waste.
Date: January 6, 2011
Creator: Disselkamp, R. S.
Partner: UNT Libraries Government Documents Department

Characterization of Oxy-combustion Impacts in Existing Coal-fired Boilers

Description: This report summarizes Year 1 results of a research program designed to use multi-scale experimental studies and fundamental theoretical models to characterize and predict the impacts of retrofit of existing coal-fired utility boilers for oxy-combustion. Through the course of Year 1 activities, great progress was made toward understanding the issues associated with oxy-combustion retrofit of coal-fired boilers. All four Year 1 milestones and objectives have been, or will be, completed on schedule and within budget. Progress in the four milestone areas may be summarized as follows: • University of Utah has performed size segregated ash composition measurements in the Oxy-Fuel Combustor (OFC). These experiments indicate that oxy-combustion retrofit may impact ash aerosol mineral matter composition. Both flame temperature and flue gas composition have been observed to influence the concentration of calcium, magnesium and iron in the fine particulate. This could in turn impact boiler fouling and slagging. • Sandia National Labs has shown that char oxidation rate is dependent on particle size (for sizes between 60 and 100 microns) by performing fundamental simulations of reacting char particles. These predictions will be verified by making time-resolved optical measurements of char particle temperature, velocity and size in bench-scale experiments before the end of Year 1. • REI and Siemens have completed the design of an oxy-research burner that will be mounted on University of Utah’s pilot-scale furnace, the L1500. This burner will accommodate a wide range of O2, FGR and mixing strategies under conditions relevant for utility boiler operation. Through CFD modeling of the different burner designs, it was determined that the key factor influencing flame stabilization location is particle heat-up rate. The new oxy-research burner and associated equipment is scheduled for delivery before the end of Year 1. • REI has completed a literature survey of slagging and fouling mechanisms in ...
Date: June 30, 2009
Creator: Adams, Bradley; Fry, Andrew; Senior, Constance; Shim, Hong; Wang, Huafeng; Wendt, Jost et al.
Partner: UNT Libraries Government Documents Department


Description: The possibility of measuring the electromagnetic form factor of the pion by extrapolation of the cross section for e/sup -/ + p 1100 deg C are n + The effects of /sup +/ + e/sup -/ was investigated. The method is based on the existence of a pole in the electropionproduction scattering amplitude as a function of the invariant momentum-transfer of the nucleon. The residue of this pole is the pion form factor multiplied by a known coefficient. Since the pole lies slightly outside the physical region of the invariant momentum transfer, an extrapolation of the experimental data is required. An approximate calculation of the electropion-production cross section was made in order to estimate the experimental accuracy necessary for a significant extrapolation. Accuracy is required which is an order of magnitude better than that achieved at present in similar experiments. (auth)
Date: February 1, 1959
Creator: Frazer, W.R.
Partner: UNT Libraries Government Documents Department

Advanced separation technology for flue gas cleanup. Quarterly technical report No. 15

Description: The objective of this work is to develop a novel system for regenerable SO{sub 2} and NO{sub x} scrubbing of flue gas that focuses on (1) a novel method for regeneration of spent SO{sub 2} scrubbing liquor and (2) novel chemistry for reversible absorption of NO{sub x}. In addition, high efficiency hollow fiber contactors (HFC) are proposed as the devices for scrubbing the SO{sub 2} and NO{sub x} from the flue gas. The system will be designed to remove more than 95% of the SO{sub x} and more than 75% of the NO{sub x} from flue gases typical of pulverized coal-fired power plants at a cost that is at least 20% less than combined wet limestone scrubbing of SO{sub x} and selective catalytic reduction of NO{sub x}. In addition, the process will make only marketable byproducts, if any (no waste streams). Our approach is to reduce the capital cost by using high efficiency hollow fiber devices for absorbing and desorbing the SO{sub 2} and NO{sub x}. We will also introduce new process chemistry to minimize traditionally well-known problems with SO{sub 2} and NO{sub x} absorption and desorption. For example, we will extract the SO{sub 2} from the aqueous scrubbing liquor into an oligomer of dimethylaniline to avoid the problem of organic liquid losses in the regeneration of the organic liquid. Our novel chemistry for scrubbing NO{sub x} will consist of water soluble phthalocyanine compounds invented by SRI and also of polymeric forms of Fe{sup ++} complexes similar to traditional NO{sub x} scrubbing media. Finally, the arrangement of the absorbers is in cassette (stackable) form so that the NO{sub x} absorber can be on top of the SO{sub x} absorber. This cassette (stacked) arrangement makes it possible for the SO{sub 2} and NO{sub x} scrubbing chambers to be separate without incurring ...
Date: February 1, 1996
Creator: Bhown, A.S.; Pakala, N.; Riggs, T. & Tagg, T.
Partner: UNT Libraries Government Documents Department

Separation of strontium from fecal matter

Description: The present invention relates to a method of separating strontium, and, more particularly, to a method of separating strontium from a sample of biomass potentially contaminated with various radionuclides. Radioactive strontium is a radionuclide which represents a hazard to man because of its long half-life and, if ingested, its tendency to be retained in the human body. In the event that radionuclides such as strontium or various actinides are ingested, it is desirable to monitor the discharge or release of these radionuclides from the human body through analysis of fecal matter. In laboratories and other facilities where potential for radionuclide contamination exists, fecal analysis for strontium is routinely conducted for individuals who are terminating from their position or are suspected of having been contaminated with radionuclides. Methods for separating and analyzing radioactive actinides from a biomass sample are well known and have been extensively developed for the US Department of Energy. These methods, described in the Department`s internal procedure, USDOE, RESL/ID, A-16, 1981, as well as in US Patent 5,190,881, involve the use of an iron phosphate precipitation step to separate actinides from a solution, or supernate. However, there are no established procedures for the separation of strontium from a biomass sample wherein an iron phosphate precipitation step is involved.
Date: December 31, 1994
Creator: Kester, D.K.
Partner: UNT Libraries Government Documents Department

Modeling of Sulfate Double-salts in Nuclear Wastes

Description: Due to limited tank space at Hanford and Savannah River, the liquid nuclear wastes or supernatants have been concentrated in evaporators to remove excess water prior to the hot solutions being transferred to underground storage tanks. As the waste solutions cooled, the salts in the waste exceeded the associated solubility limits and precipitated in the form of saltcakes. The initial step in the remediation of these saltcakes is a rehydration process called saltcake dissolution. At Hanford, dissolution experiments have been conducted on small saltcake samples from five tanks. Modeling of these experimental results, using the Environmental Simulation Program (ESP), are being performed at the Diagnostic Instrumentation and Analysis Laboratory (DIAL) at Mississippi State University. The River Protection Project (RPP) at Hanford will use these experimental and theoretical results to determine the amount of water that will be needed for its dissolution and retrieval operations. A comprehensive effort by the RPP and the Tank Focus Area continues to validate and improve the ESP and its databases for this application. The initial effort focused on the sodium, fluoride, and phosphate system due to its role in the formation of pipeline plugs. In FY 1999, an evaluation of the ESP predictions for sodium fluoride, trisodium phosphate dodecahydrate, and natrophosphate clearly indicated that improvements to the Public database of the ESP were needed. One of the improvements identified was double salts. The inability of any equilibrium thermodynamic model to properly account for double salts in the system can result in errors in the predicted solid-liquid equilibria (SLE) of species in the system. The ESP code is evaluated by comparison with experimental data where possible. However, data does not cover the range of component concentrations and temperatures found in many tank wastes. Therefore, comparison of ESP with another code is desirable, and may illuminate problems ...
Date: October 30, 2000
Creator: Toghiani, B.
Partner: UNT Libraries Government Documents Department