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The Manufacture of Sulphuric Acid in the United States

Description: Report issued by the Bureau of Mines over the production of sulfuric acid. As stated in the introduction, "the present bulletin was prepared to cover the main facts in regard to the industry in this country, including a discussion of the supplies of sulfur-bearing raw materials, the situation of the acid plants, the principal points in regard to manufacturing processes, and the uses of the acid" (p. 2). This report includes tables, illustrations, photographs, and a map.
Date: July 1920
Creator: Wells, Arthur Edward & Fogg, Donald E.
Partner: UNT Libraries Government Documents Department

CATALYSTS NHI Thermochemical Systems FY 2009 Year-End Report

Description: Fiscal Year 2009 work in the Catalysts project focused on advanced catalysts for the decomposition of sulfuric acid, a reaction common to both the Sulfur-Iodine (S-I) cycle and the Hybrid Sulfur cycle. Prior years’ effort in this project has found that although platinum supported on titanium oxide will be an acceptable catalyst for sulfuric acid decomposition in the integrated laboratory scale (ILS) project, the material has short comings, including significant cost and high deactivation rates due to sintering and platinum evaporation. For pilot and larger scale systems, the catalyst stability needs to be improved significantly. In Fiscal Year 2008 it was found that at atmospheric pressure, deactivation rates of a 1 wt% platinum catalyst could be reduced by 300% by adding either 0.3 wt% iridium (Ir) or 0.3 wt% ruthenium (Ru) to the catalyst. In Fiscal Year 2009, work focused on examining the platinum group metal catalysts activity and stability at elevated pressures. In addition, simple and complex metal oxides are known to catalyze the sulfuric acid decomposition reaction. These metal oxides could offer activities comparable to platinum but at significantly reduced cost. Thus a second focus for Fiscal Year 2009 was to explore metal oxide catalysts for the sulfuric acid decomposition reaction. In Fiscal Year 2007 several commercial activated carbons had been identified for the HI decomposition reaction; a reaction specific to the S-I cycle. Those materials should be acceptable for the pilot scale project. The activated carbon catalysts have some disadvantages including low activity at the lower range of reactor operating temperature (350 to 400°C) and a propensity to generate carbon monoxide in the presence of water that could contaminate the hydrogen product, but due to limited funding, this area had low priority in Fiscal Year 2009. Fiscal Year 2009 catalyst work included five tasks: development, and testing ...
Date: September 1, 2009
Creator: Ginosar, Daniel M.
Partner: UNT Libraries Government Documents Department

Commercial Alloys for Sulfuric Acid Vaporization in Thermochemical Hydrogen Cycles

Description: Most thermochemical cycles being considered for producing hydrogen include a processing stream in which dilute sulfuric acid is concentrated, vaporized and then decomposed over a catalyst. The sulfuric acid vaporizer is exposed to highly aggressive conditions. Liquid sulfuric acid will be present at a concentration of >96 wt% (>90 mol %) H2SO4 and temperatures exceeding 400oC [Brown, et. al, 2003]. The system will also be pressurized, 0.7-3.5 MPa, to keep the sulfuric acid in the liquid state at this temperature and acid concentration. These conditions far exceed those found in the commercial sulfuric acid generation, regeneration and handling industries. Exotic materials, e.g. ceramics, precious metals, clad materials, etc., have been proposed for this application [Wong, et. al., 2005]. However, development time, costs, reliability, safety concerns and/or certification issues plague such solutions and should be considered as relatively long-term, optimum solutions. A more cost-effective (and relatively near-term) solution would be to use commercially-available metallic alloys to demonstrate the cycle and study process variables. However, the corrosion behavior of commercial alloys in sulfuric acid is rarely characterized above the natural boiling point of concentrated sulfuric acid (~250oC at 1 atm). Therefore a screening study was undertaken to evaluate the suitability of various commercial alloys for concentration and vaporization of high-temperature sulfuric acid. Initially alloys were subjected to static corrosion tests in concentrated sulfuric acid (~95-97% H2SO4) at temperatures and exposure times up to 200oC and 480 hours, respectively. Alloys with a corrosion rate of less than 5 mm/year were then subjected to static corrosion tests at a pressure of 1.4 MPa and temperatures up to 375oC. Exposure times were shorter due to safety concerns and ranged from as short as 5 hours up to 144 hours. The materials evaluated included nickel-, iron- and cobalt-based commercial alloys. The corrosion rates in these tests ...
Date: October 1, 2005
Creator: Lillo, Thomas M. & Delezene-Briggs, Karen M.
Partner: UNT Libraries Government Documents Department

Speciation of Heptavalent Technetium in Sulfuric Acid: Structural and Spectroscopic Studies.

Description: The speciation of Tc(VII) in 12 M sulfuric acid was studied by NMR, UV-visible and XAFS spectroscopy, experimental results were supported by DFT calculation and were in agreement with the formation of TcO{sub 3}OH(H{sub 2}O){sub 2}. In summary, the speciation of heptvalent technetium has been investigated in sulfuric acid. In 12 M H{sub 2}SO{sub 4}, a yellow solution is observed, and its {sup 99}Tc NMR spectrum is consistent with a heptavalent complex. The yellow solution was further characterized by EXAFS spectroscopy, and results are consistent with the formation of TcO{sub 3}(OH)(H{sub 2}O){sub 2}. No technetium heptoxide or sulfato- complexes were detected in these conditions. The molecular structure of TcO{sub 3}(OH)(H{sub 2}O){sub 2} has been optimized by DFT techniques, and the structural parameters are well in accordance with those found by XAFS spectroscopy. The experimental electronic spectra exhibit ligand-to-metal charge transfer transitions that have been assigned using TDDFT methods. Calculations demonstrate the theoretical electronic spectrum of TcO{sub 3}(OH)(H{sub 2}O){sub 2} to be in very good agreement with the experimental one. Recent experiments in 12 M H{sub 2}SO{sub 4} show the yellow solution to be very reactive in presence of reducing agents presumably forming low valent Tc species. Current spectroscopic works focus on the speciation of these species.
Date: June 10, 2010
Creator: Poineau, Frederic; Weck, Philippe F.; German, Konstantin; Maruk, Alesya; Kirakosyan, Gayane; Lukens, Wayne et al.
Partner: UNT Libraries Government Documents Department

Report of 1,000 Hour Catalyst Longevity Evaluation

Description: This report presents the results of a 1,000 hour, high-pressure, catalyst longevity test for the decomposition of concentrated sulfuric acid. The reaction is used for both the sulfur-iodine (S-I) cycle and hybrid sulfur cycle. By the time of the delivery date of April 17, 2009, for project milestone no. 2NIN07TC050114, the 1% Pt/TiO2 catalyst had been in the reaction environment for 658 hours. During the first 480 hours of testing, the catalyst activity provided stable, near-equilibrium yields of 46.8% SO2 and 22.8% O2. However, product yields declined at sample exposure times >480 hours. At 658 hours of operation, catalyst activity (based on oxygen yield) declined to 57% relative to the stable period of catalyst activity. Thus, as of April 17, this catalyst did not provide the desired stability level of <10% degradation per 1,000 hours. The experiment was terminated on April 27, after 792 hours, when a fitting failed and the catalyst was displaced from the reactor such that the sample could not be recovered. Oxygen conversion at the end of the experiment was 12.5% and declining, suggesting that at that point, catalyst activity had decreased to 54% of the initial level.
Date: June 1, 2009
Creator: Ginosar, Daniel M.
Partner: UNT Libraries Government Documents Department

Impact of Small Chemistry Variations in Plate and Weld Filler Metal on the Corrosion Performance of Ni-Cr-Mo Alloys

Description: The ASTM standard B 575 provides the requirements for the chemical composition of Nickel-Chromium-Molybdenum (Ni-Cr-Mo) alloys such as Alloy 22 (N06022) and Alloy 686 (N06686). The compositions of each element are given in a range. For example, the content of Mo is specified from 12.5 to 14.5 weight percent for Alloy 22 and from 15.0 to 17.0 weight percent for Alloy 686. It was important to determine how the corrosion rate of welded plates of Alloy 22 using Alloy 686 weld filler metal would change if heats of these alloys were prepared using several variations in the composition of the elements even though still in the range specified in B 575. Seven heats of plate were welded with seven heats of wire. Immersion corrosion tests were conducted in a boiling solution of sulfuric acid plus ferric sulfate (ASTM G 28 A) using both as-welded (ASW) coupons and solution heat-treated (SHT) coupons. Results show that the corrosion rate was not affected by the chemistry of the materials in the range specified in the standard B 575.
Date: February 5, 2006
Creator: Fix, D V & Rebak, R B
Partner: UNT Libraries Government Documents Department

Test Plan for Characterization Testing of SO2-depolarized Electrolyzer Cell Designs

Description: SRNL received funding in FY 2005 to test the Hybrid Sulfur (HyS) Process for generating hydrogen. This technology employs an electrolyzer that uses a sulfur dioxide depolarized anode to greatly reduce the electrical energy requirement. The required current is the same as for conventional electrolysis of water, but the required cell voltage is reduced. The electrolyzer is a key part of HyS technology. Completing the material loop for HyS requires a high temperature decomposition of sulfuric acid to regenerate the sulfur dioxide gas needed for the anode reaction. Oxygen is also produced and could be sold. The decomposition of sulfuric acid is being studied by others in a separately funded task. It is not included in this SRNL task.
Date: February 15, 2006
Creator: Steimke, J. L.
Partner: UNT Libraries Government Documents Department


Description: Results obtained by means of x-ray photoelectron spectroscopy and internal reflection infrared spectroscopy demonstrate the feasibility of heterogeneous oxidation of sulfur dioxide on soot particles in air. Sulfuric acid formed in this process can be neutralized on basic surface sites of soot particles, resulting in the formation of carbonium and/or oxonium sulfate. Hydrolysis of these salts into cyclic hemiacetals and sulfuric acid is expected.
Date: December 1, 1975
Creator: Chang, S.G. & Novakov, T.
Partner: UNT Libraries Government Documents Department

An improved criterion for new particle formation in diverse environments

Description: A dimensionless theory for new particle formation (NPF) was developed, using an aerosol population balance model incorporating recent developments in nucleation rates and measured particle growth rates. Based on this theoretical analysis, it was shown that a dimensionless parameter Lg, characterizing the ratio of the particle scavenging loss rate to the particle growth rate, exclusively determined whether or not NPF would occur on a particular day. This parameter determines the probability that a nucleated particle will grow to a detectable size before being lost by coagulation with the pre-existing aerosol. Cluster-cluster coagulation was shown to contribute negligibly to this survival probability under conditions pertinent to the atmosphere. Data acquired during intensive measurement campaigns in Tecamac (MILAGRO), Atlanta (ANARChE), Boulder, and Hyytiala (QUEST II, QUEST IV, and EUCAARI) were used to test the validity of Lg as an NPF criterion. Measurements included aerosol size distributions down to 3 nm and gas-phase sulfuric acid concentrations. The model was applied to 77 NPF events and 19 non-events (characterized by growth of pre-existing aerosol without NPF) measured in diverse environments with broad ranges in sulfuric acid concentrations, ultrafine number concentrations, aerosol surface areas, and particle growth rates (nearly two orders of magnitude). Across this diverse data set, a nominal value of Lg = 0.7 was found to determine the boundary for the occurrence of NPF, with NPF occurring when Lg &lt; 0.7 and being suppressed when Lg &gt; 0.7. Moreover, nearly 45% of measured Lg values associated with NPF fell in the relatively narrow range of 0.1 &lt; Lg &lt; 0.3.
Date: March 15, 2010
Creator: Kuang, C.; Riipinen, I.; Sihto, S.-L.; Kulmala, M.; McCormick, A. & McMurry, P.
Partner: UNT Libraries Government Documents Department


Description: Dissolution methods were developed to permit representative sampling of the slurry of corrosion and fission products collected by the HRT chemical process-ing plant. The procedure selected for HRT-CPP application was to use 15 ml of 10.8 M H/sub 2/SO/sub 4/ per gram of solids with agitation by boiling in a tantalum-lined dissolver. (auth)
Date: August 1, 1958
Creator: Snider, J.W. & Haas, P.A.
Partner: UNT Libraries Government Documents Department

Preparation of Uranium(IV) Nitrate Solutions

Description: A procedure was developed for the preparation of uranium(IV) nitrate solutions in dilute nitric acid. Zinc metal was used as a reducing agent for uranium(VI) in dilute sulfuric acid. The uranium(IV) was precipitated as the hydrated oxide and dissolved in nitric acid. Uranium(IV) nitrate solutions were prepared at a maximum concentration of 100 g/l. The uranium(VI) content was less than 2% of the uranium(IV). (auth)
Date: July 1, 1961
Creator: Ondrejcin, R. S.
Partner: UNT Libraries Government Documents Department

Nucleation and growth processes of atmospheric aerosols and clouds

Description: This project seeks to gain enhanced understanding of the rate of formation and growth of new particles and of cloud droplets as a function of pertinent controlling atmospheric variables, thereby permitting accurate representation of these processes in climate models. Aerosol size distributions are shaped by complex nucleation and growth and mixing processes that are difficult to represent in models, due to the need to accurately represent the evaporation/growth kinetics for each of the billions of discrete cluster sizes in the growth sequence, ranging from molecular clusters to particles of radius of several tenths of a micrometer or greater. A potentially very powerful means of solving this problem may be given by the method of moments (MOM), which tracks the time dependence of just the lower-order radial moments of the size distribution without requiring knowledge of the distribution itself.
Date: November 1, 1995
Creator: Schwartz, S.E. & McGraw, R.L.
Partner: UNT Libraries Government Documents Department

An Evaluation of the Sulfuric Acid-Sodium Nitrite Etch for Zircaloy-2

Description: Preliminary experiments indicate that there are no significant differences in the corrosion rates of zirconium or Zircaloy-2 after etching with the nitric--hydrofluoric solution or the sulfuric--nitrite solution, provided proper etching and washing techniques are followed. Incomplete removal of the residual etchant is deleterious to the corrosion resistance; however, this effect in the case of the sulfuric--nitrite solution is not as pronounced as in the case of the nitric--hydrofluoric acid solution. The anticipated advantages in the new etch were not completely realized. Additional development aimed at modifying the sulfuric--nitrite etch would have to be performed in order to overcome the disadvantages before recommendation for the adoption of the etch could be made. (auth)
Date: February 17, 1954
Creator: Kass, S.
Partner: UNT Libraries Government Documents Department

Potential oscillations and S-shaped polarization curve in the continuous electro-oxidation of CO on platinum single-crystal electrodes

Description: The occurrence of an S-shaped polarization curve in a simple model for the continuous electrochemical oxidation of CO on a platinum electrode is discussed. In the model, the S-shaped polarization curve is caused by the competitive Langmuir-Hinshelwood mechanism between surface-bonded CO and OH. The reaction is studied experimentally on single-crystal platinum rotating disk electrodes in perchloric and sulfuric acid solution, and it is shown that the voltammetry is in good agreement with the model predictions. When studied under current-controlled conditions, a fast galvanodynamic scan indeed suggests the existence of the S-shaped polarization curve. At lower scan rates, however, irregularities and small-amplitude irregular fluctuations or oscillations in potential are observed. Very regular potential oscillations under current-controlled conditions are observed only on Pt(111) in sulfuric acid. The possible origin of these irregularities and oscillations is discussed in relation to the existing theories of electrochemical instabilities.
Date: March 1, 2001
Creator: Koper, Marc T.M.; Schmidt, Thomas J.; Markovic, Nenad M. & Ross, Philip N.
Partner: UNT Libraries Government Documents Department


Description: ABS> The removal rates of iron, nickel, and chromium from synthetic stainless steel waste solutions during electrolysis over a mercury cathode were studied. The loading capacity of the mercury for the stainless steel metals was estimated on the basis of laboratory experiments to be about two% by weight. The laboratory data indicated that, at an electrode potential of --1.80 voits vs S.C.E., 85 ampere-hours per liter of waste removed essentially all of the stainless steel ions from a sulfuric acid solution containing 0.13M metal ions at 35 deg C. (auth)
Date: February 12, 1962
Creator: Anderson, D. R. & Rhodes, D. W.
Partner: UNT Libraries Government Documents Department


Description: In the class of the polycondensed aromatic hydrocarbons, the concept of localized charge in a {sigma}-complex, e.g., the carbonium ion formed by addition of a proton or other electrophile to an aromatic ring, has so far received experimental evidence only in the case of anthracene. The ultraviolet spectrum of this compound in sulfuric acid is similar to that of the benzhydryl cation. Ph{sub c}C{sup +}Me. This result implies the protonation of anthracene at one meso-carbon atom and the localization of the positive charge at the other. The {sigma}-complex of the potent carcinogen 7,12-dimethylbenz[a]anthracene (DMBA) in acidic medium offers another example of this type of charge localization. The determination of structure was achieved by comparing the NMR spectra of DMBA in neutral and acidic solvents. The ratio of the integrated intensities of the proton peaks in the spectrum of DMBA is, from right to left, 3:3:5:1:1:2:1. The assignment of the 7-CH{sub 3} ({sigma}3.00) and 12-CH{sub 3} ({sigma}3.29) resonances was made by comparison with the spectra of 7-methylbenz[a]anthracene (7-CH{sub 3}, {sigma}3.03) and 12-methylbenz[a]anthracene (12-CH{sub 3}, {sigma}3.32) under the same conditions. A good general correlation exists between the methyl chemical shifts of the twelve monosubstituted methylbenzanthrancenes and the corresponding aryl protons of benzanthracene.
Date: April 1, 1971
Creator: Cavalieri, Ercole & Calvin, Melvin.
Partner: UNT Libraries Government Documents Department