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Effects of Aging Quartz Sand and Hanford Site Sediment with Sodium Hydroxide on Radionuclide Sorption Coefficients and Sediment Physical and Hydrologic Properties: Final Report for Subtask 2a

Description: Column and batch experiments were conducted in fiscal year 1998 at Pacific Northwest National Laboratory to evaluate the effect of varying concentrations of NaOH on the sorptive, physical, and hydraulic properties of two media, a quartz sand and a composite subsurface sediment from the 200-East Area of the Hanford Site. The NaOH solutions were used as a simplified effluent from a low-activity glass waste form. These experiments were conducted over a limited (O-to 10-month) contact time, with respect to the 10,000-to 100,000-year scenarios described in the Immobilized Low-Activity Waste- Performance Assessment (ILAW-PA). Wheq these two solids were put in contact with the NaOH solutions, dissolution was evident by a substantial increase in dissolved Si concentrations in the leachates. Incremental increases in NaOH con- centrations, resulted in corresponding increases in Si concentrations. A number of physical and hydraulic properties also changed as the NaOH concentrations were changed. It was observed that quartz sand was less reactive than the composite sediment. Further, moisture- retention measurements were made on the quartz sand and composite sedimen$ which showed that the NaOH-treated solids retained more water than the non-NaOH-treated solids. Because the other chemical, physical, and hydraulic measurements did not change dramatically after the high-NaOH treatments, the greater moisture retention of the high-NaOH treatments was attributed to a "salt effect" and not to the formation of small particles during the dissolution (weathering). The distribution coefficients (IQ) for Cs and Sr were measured on the NaOH-treated sediments, with decreases from -3,000 to 1,000 and 1,300 to 300 mL/g noted, respectively, at the 0.01-to 1.O-M NaOH levels. There was no apparent trend for the Sr & values with contact time. The lack of such a trend sug- gests that dissolution of sediment particles is not controlling the drop in IQ rather, it is the competition of the ...
Date: December 4, 1998
Creator: Kaplan, DI; Ritter, JC & Parker, KE
Partner: UNT Libraries Government Documents Department

HEAT OF DILUTION CALCULATION FOR 19 MOLAR SODIUM HYDROXIDE WITH WATER FOR USE IN 241-S-112

Description: High concentration caustic solutions are known to cause stress corrosion cracking in carbon steel at elevated temperature. This calculation establishes the conditions where heat of dilution will not cause the solution temperature--concentration to exceed the boundary for stress corrosion cracking as established by NACE International.
Date: February 20, 2007
Creator: Barton, W. B.
Partner: UNT Libraries Government Documents Department

Oxidative Dissolution of Nickel Metal in Hydrogenated Hydrothermal Solutions

Description: A platinum-lined, flowing autoclave facility is used to investigate the solubility behavior of metallic nickel in hydrogenated ammonia and sodium hydroxide solutions between 175 and 315 C. The solubility measurements were interpreted by means of an oxidative dissolution reaction followed by a sequence of Ni(II) ion hydrolysis reactions: Ni(s) + 2H+(aq) = Ni2+(aq) + H2(g) and Ni{sup 2+}(aq) + nH{sub 2}O = Ni(OH){sub n}{sup 2-n}(aq) + nH{sup +}(aq) where n = 1 and 2. Gibbs energies associated with these reaction equilibria were determined from a least-squares analysis of the data. The extracted thermochemical properties ({Delta}fG{sup 0}, {Delta}fH{sup 0} and S{sup 0}) for Ni2{sup +}(aq), Ni(OH){sup +}(aq) and Ni(OH){sub 2}(aq) were found to be consistent with those determined in a previous solubility study of NiO/Ni(OH){sub 2} conducted in our laboratory. The thermodynamic basis of the Ni/NiO phase boundary in aqueous solutions is examined to show that Ni(s) is stable relative to NiO(s) in solutions saturated at 25 C with 1 atm H{sub 2} for temperatures below 309 C.
Date: March 27, 2007
Creator: Ziemniak S. E.; Guilmette, P. A.; Turcotte, R. A. & Tunison, H. M.
Partner: UNT Libraries Government Documents Department

REMOVAL OF MOLYBDENUM FROM ACID LEACH LIQUORS BY ACTIVATED CARBON

Description: Data are presented on the absorption of molybdenum on activated carbon. The effect of retention time and linear flow on absorption, the use of sodium hydroxide as an eluant, and the possibility of recovering molybdenum from the caustic eluate are discussed. (auth)
Date: July 29, 1958
Creator: Hollis, E.T. & Dixon, H.E.
Partner: UNT Libraries Government Documents Department

Determination of the solubility of Np(IV), Pu(III) - (VI),Am(III) - (VI), and Te(IV), (V) hydroxo compounds in 0.5 - 14 M NaOH solutions

Description: The solubilities of Am(III), Np(IV), Pu(IV), Tc(IV), Np(V), Pu(V), Am(V), and Tc(V) hydroxo compounds were studied in 0.5 to 14 M NaOH solutions at 25{+-}2 {degrees}C. The effects of fluoride, phosphate, carbonate, oxalate, and some other organic complexing agents on the solubilities of Np(IV), Pu(IV), and TC(IV) hydroxides were investigated at 1.0 and 4.0 M NAOH. Some predictions were made on the dissolved (I.V) and (V) species present in alkali solutions.
Date: September 24, 1996
Creator: Delegard, C.H.
Partner: UNT Libraries Government Documents Department

Caustic Leaching of Sludges from Selected Hanford Tanks

Description: The objective of this project was to measure the caustic dissolution behavior of sludge components from selected Hanford waste tank sludge samples under different conditions. The dissolution of aluminum, chromium, and other constituents of actual sludge samples in aqueous sodium hydroxide solution was evaluated using various values of temperature, sodium hydroxide concentration, volume of caustic solution per unit mass of sludge (liquid:solids ratio), and leaching time.
Date: August 1, 1998
Creator: Chase, C.W.; Egan, B.Z. & Spencer, B.B.
Partner: UNT Libraries Government Documents Department

Consequence analysis of a NaOH solution spray release during addition to waste tank. Revision 2

Description: Toxicological consequences are presented for three postulated accidents involving caustic soda (sodium hydroxide) addition to a waste tank to adjust the tank waste pH. These are spray from the skid mounted delivery system, spray from a cargo tank truck, and rupture of a cargo tank truck. Consequences for the onsite and offsite receptor are calculated.
Date: July 8, 1997
Creator: Van Vleet, R.J. & Lancing, L.C.
Partner: UNT Libraries Government Documents Department

Consequence analysis of a postulated NaOH release from the 2727-W sodium storage facility

Description: Toxicological and radiological consequences were calculated for a maximum sodium fire in the 2727-W Sodium Storage Facility. The sodium is solid and cannot leak out of the tanks. The maximum fire therefore corresponded to the maximum cross-sectional area of one tank. It was shown that release of the entire facility inventory of 22 Na is insufficient to produce an appreciable effect.
Date: September 27, 1996
Creator: Himes, D.A.
Partner: UNT Libraries Government Documents Department

Consequence analysis of an unmitigated NaOH solution spray release during addition to waste tank

Description: Toxicological consequences were calculated for a postulated maximum caustic soda (NaOH) solution spray leak during addition to a waste tank to adjust tank pH. Although onsite risk guidelines were exceeded for the unmitigated release, site boundary consequences were below the level of concern. Means of mitigating the release so as to greatly reduce the onsite consequences were recommended.
Date: August 21, 1996
Creator: Himes, D.A., Westinghouse Hanford
Partner: UNT Libraries Government Documents Department

Consequence analysis of a NaOH solution spray release during addition to waste tank

Description: Toxicological consequences were calculated for a postulated maximum caustic soda (NaOH) solution spray leak during addition to a waste tank to adjust tank pH. Although onsite risk guidelines were exceeded for the unmitigated release, site boundary consequences were below the level of concern. Means of mitigating the release so as to greatly reduce the onsite consequences were recommended. Consequences for the mitigated release were estimated and both onsite and offsite consequences were found to negligible.
Date: October 9, 1996
Creator: Himes, D.A., Westinghouse Hanford Co.
Partner: UNT Libraries Government Documents Department

Quantification of hydroxide in aqueous solutions by Raman spectroscopy

Description: Quantification of hydroxide in aqueous solutions by Raman spectroscopy is complicated by the fact that the O-H stretching band of hydroxide is overlapped by the broad, symmetric O-H stretching band of water. This overlap is further complicated by the fact that the shape of the O-H stretching band of water is strongly influenced by the concentration of hydroxide. The O-H stretching band of water is believed to consist of five components that result from differing configurations of intramolecular hydrogen bonding. The Raman spectral region from 300 to 4,450 cm{sup {minus}1} was investigated for NaOH solutions ranging in concentration from 0.2 to 50 weight percent. At approximately 5 weight percent NaOH, a distinct shoulder appears on the high energy side of the O-H stretching band of water. As the NaOH concentration increases, this shoulder becomes a sharp distinct band at 3,600 cm{sup {minus}1} which is still not resolved from the O-H stretching band of water. As the O-H stretching band of hydroxide increases, the O-H stretching band of water broadens and its contour becomes smoother. By curve fitting five Gaussian functions to the O-H stretching band of water, the asymmetric band due to hydroxide was extracted from the composite band of the NaOH solution. The curve fitting routine resulted in a linear relationship for the area of the hydroxide band in the concentration range from 5 to 50 weight percent NaOH. The uncertainty in the curve fitting at concentrations below 5 weight percent was too large to establish a reliable calibration curve. Below 5 weight percent NaOH, direct spectral subtraction of the water band from the NaOH solution band resulted in a linear relationship in the range of 5 down to 0.2 weight percent NaOH. The peak shape obtained for the hydroxide band by the two different techniques was very similar. ...
Date: December 1, 1997
Creator: Shaffer, C.D.
Partner: UNT Libraries Government Documents Department

Cutting fluid study for single crystal silicon

Description: An empirical study was conducted to evaluate cutting fluids for Single Point Diamond Turning (SPDT) of single crystal silicon. The pH of distilled waster was adjusted with various additives the examine the effect of pH on cutting operations. Fluids which seemed to promote ductile cutting appeared to increase tool wear as well, an undesirable tradeoff. High Ph sodium hydroxide solutions showed promise for further research, as they yielded the best combination of reduced tool wear and good surface finish in the ductile regime. Negative rake tools were verified to improve the surface finish, but the negative rake tools used in the experiments also showed much higher wear than conventional 0{degree} rake tools. Effects of crystallographic orientation on SPDT, such as star patterns of fracture damage forming near the center of the samples, were observed to decrease with lower feedrates. Silicon chips were observed and photographed, indicative of a ductile materials removal process.
Date: May 5, 1998
Creator: Chargin, D.
Partner: UNT Libraries Government Documents Department

Consequence analysis of a postulated NaOH release from the 2727-W sodium storage facility

Description: Toxicological and radiological consequences were calculated for a maximum sodium fire in the 2727-W Sodium Storage Facility. The sodium is solid and cannot leak out of the tanks. The maximum fire therefore corresponded to the maximum cross-sectional area of one tank. It was shown that release of the entire facility inventory of {sup 22}Na is insufficient to produce an appreciable effect.
Date: August 2, 1996
Creator: Himes, D.A., Westinghouse Hanford
Partner: UNT Libraries Government Documents Department

Effects of oxygen cover gas and NaOH dilution on gas generation in tank 241-SY-101 waste

Description: Laboratory studies are reported of gas generation in heated waste from tank 241-SY-101. The rates of gas generation and the compositions of product gas were measured. Three types of tests are compared. The tests use: undiluted waste, waste diluted by a 54% addition of 2.5 M NaOH, and undiluted waste with a reactive cover gas of 30% Oxygen in He. The gas generation rate is reduced by dilution, increased by higher temperatures (which determines activation energies), and increased by reactions of Oxygen (these primarily produce H{sub 2}). Gases are generated as reduction products oxidation of organic carbon species by nitrite and oxygen.
Date: May 30, 1996
Creator: Person, J.C.
Partner: UNT Libraries Government Documents Department

Analysis of NaOH releases for Hanford tank farms

Description: This document supports the development and presentation of the following accident scenario in the TWRS Final Safety Analysis Report: Caustic Spray Leak. The calculations needed to quantify the risk associated with this accident scenario are included within.
Date: July 25, 1996
Creator: Ryan, G. W.
Partner: UNT Libraries Government Documents Department

Safety evaluation for packaging (Onsite) for the PUREX facility MC-312 cargo tank

Description: This safety evaluation for packaging authorizes transport of sodium hydroxide solutions, potassium hydroxide solutions, and water in the MC-312 cargo tank, registration number HO-64-05473,on the Hanford Site without a complete U.S. Department of Transportation maintenance inspection. These materials are acceptable for transport in the MC- 312 cargo tank per 49 CFR172.101.
Date: July 18, 1996
Creator: Flanagan, B. D.
Partner: UNT Libraries Government Documents Department

Cesium Hydroxide Fusion Dissolution of Analytical Reference Glass-1 in Both Powder and Shard Form

Description: CsOH has been shown to be an effective and convenient dissolution reagent for Analytical Reference Glass-1 (ARG-1). This glass standard was prepared from nonradioactive DWPF Start-up Glass. Therefore, its composition is similar to DWPF product glass and many of the glass matrices prepared at SRTC.The principal advantage of the CsOH fusion dissolution is that the reagent does not add the alkali metals Li, Na, and K usually needed by SRS customers. Commercially available CsOH is quite pure so that alkali metals can be measured accurately, often without blank corrections. CsOH fusions provide a single dissolution method for applicable glass to replace multiple dissolution schemes used by most laboratories. For example, SRTC glass samples are most commonly dissolved with a Na{sub 2}O{sub 2}-NaOH fusion (ref.1) and a microwave- assisted acid dissolution with HNO{sub 3}-HF-H{sub 3}BO{sub 3}-HCl (ref.2). Othe laboratories use fusion methods based on KOH, LiBO{sub 2}, and Na{sub 2}CO{sub 3} CsOH fusion approach reduces by half not only the work in the dissolution laboratory, but also in the spectroscopy laboratories that must analyze each solution.Experiments also revealed that glass shards or pellets are rapidly attacked if the flux temperature is raised considerably above the glass softening point. The softening point of ARG-1 glass is near 650 degrees C. Fusions performed at 750 degrees C provided complete dissolutions and accurate elemental analyses of shards. Successful dissolution of glass shards was demonstrated with CsOH, Na{sub 2}O{sub 2}, NaOH, KOH, and RbOH. Ability to dissolve glass shards is of considerable practical importance. Crushing glass to a fine powder is a slow and tedious task, especially for radioactive glasses dissolved in shielded cells. CsOH fusion of glass powder or shards is a convenient, cost-effective dissolution scheme applicable in SRTC, the DWPF, and the commercial glass industry.
Date: April 1998
Creator: Coleman, C. J. & Spencer, W. A.
Partner: UNT Libraries Government Documents Department

Aluminum removal from washed sludge

Description: Purpose of this project is to reduce the volume of storage tank sludge to be treated by removing the Al and other nonradioactive components. In initial sludge surrogate studies, Al, Cr, and Zn showed the highest solubility in NaOH solutions; Ce and Zr were the least soluble of the elements tested. Removal of Fe and Bi approached 2%, the rest of the elements studied showed <1% removal. Amount of Al removed increased as the NaOH conc. increased from 0.1 to 6 M. Sequential washing of the sludge surrogate with 3 M NaOH removed 84% of the Al, 39% of the Cr, and 65% of the Zn. Surrogate sludges containing U and Th were also studied.
Date: December 31, 1995
Creator: Egan, B.Z.; Collins, J.L. & Ensor, D.D.
Partner: UNT Libraries Government Documents Department

Analysis of Current Distribution in Electrolytic Cells With Flowing Mercury Cathodes

Description: An idealized model is postulated embodying the essential features of industrial caustic-chlorine cells with horizontal flowing-mercury cathodes. This model is examined in detail, and relations expressing the local anode potential, cathode potential, and ohmic potential drop in the electrolyte in terms of local current density and other parameters are established. These relations are combined to give a system of equations relating current density at any location along the cell to applied total potential and to operating conditions in the cell upstream of the point in question. Numerical solutions of these equations for several cases of cell operating conditions are carried out on a digital computing machine. The effects of changes in operating parameters upon average current density, individual electrode potentials, and current distribution are evaluated. (auth)
Date: July 19, 1960
Creator: Grens, E. A., II
Partner: UNT Libraries Government Documents Department

Alternative Sodium Recovery Technology—High Hydroxide Leaching: FY10 Status Report

Description: Boehmite leaching tests were carried out at NaOH concentrations of 10 M and 12 M, temperatures of 85°C and 60°C, and a range of initial aluminate concentrations. These data, and data obtained during earlier 100°C tests using 1 M and 5 M NaOH, were used to establish the dependence of the boehmite dissolution rate on hydroxide concentration, temperature, and initial aluminate concentration. A semi-empirical kinetic model for boehmite leaching was fitted to the data and used to calculate the NaOH additions required for leaching at different hydroxide concentrations. The optimal NaOH concentration for boehmite leaching at 85°C was estimated, based on minimizing the amount of Na that had to be added in NaOH to produce a given boehmite conversion.
Date: February 4, 2011
Creator: Mahoney, Lenna A.; Neiner, Doinita; Peterson, Reid A.; Rapko, Brian M.; Russell, Renee L. & Schonewill, Philip P.
Partner: UNT Libraries Government Documents Department