426 Matching Results

Search Results

Advanced search parameters have been applied.

Nano Structured Activated Carbon for Hydrogen Storge

Description: Development of a nanostructured synthetic carbons materials that have been synthesized by thermal-decomposition of aromatic rich polyether such as poly(ether ether ketone) (PEEK) is reported. These polymers based nanostructured carbons efficacious for gas adsorption and storage and have Brunauer-Emmett-Teller (BET) surface area of more than 3000 m2/g, and with average pore diameter of < 2nm. Surface-area, pore characteristics, and other critical variables for selecting porous materials of high gas adsorption capacities are presented. Analysis of the fragments evolved under various carbonization temperatures, and the correlation between the activation and carbonization temperatures provides a mechanistic perspective of the pore evolution during activation. Correlations between gas (N2 and H2) adsorption capacity and porous texture of the materials have been established. The materials possess excellent hydrogen storage properties, with hydrogen storage capacity up to 7.4 wt% (gravimetric) and ~ 45 g H2 L-1 (volumetric) at -196oC and 6.0 MPa.
Date: February 27, 2013
Creator: Cabasso, Israel & Yuan, Youxin
Partner: UNT Libraries Government Documents Department

Removal of Mercury from SBW Vitrification Off-Gas by Activated Carbon

Description: Radioactive, acidic waste stored at the Idaho Nuclear Technology and Engineering Center (INTEC) have been previously converted into a dry, granular solid at the New Waste Calcining Facility (NWCF). As an alternative to calcination, direct vitrification of the waste, as well as the calcined solids in an Idaho Waste Vitrification Facility (IWVF) is being considered to prepare the waste for final disposal in a federal repository. The remaining waste to be processed is Sodium-Bearing Waste (SBW). Off-gas monitoring during NWCF operations have indicated that future mercury emissions may exceed the proposed Maximum Achievable Control Technology (MACT) limit of 130 ug/dscm (micrograms/dry standard cubic meter) @ 7% O2 for existing Hazardous Waste Combustors (HWC) if modifications are not made. Carbon monoxide and hydrocarbon emissions may also exceed the MACT limits. Off-gas models have predicted that mercury levels in the off-gas from SBW vitrification will exceed the proposed MACT limit of 45 ug/dscm @ 7% O2 for new HWCs. NO2/44% H2O.
Date: September 1, 2001
Creator: Deldebbio, John Anthony; Watson, T. T. & Kirkham, Robert John
Partner: UNT Libraries Government Documents Department


Description: This document presents a detailed evaluation of selected alternative treatment options to granular activated carbon (GAC) for removing carbon tetrachloride generated from the groundwater pump-and-treat system at the 200-ZP-I Operable Unit (OU) in the 200 West Area of the Hanford Site. This evaluation of alternative treatment options to GAC is also applicable to the vadose zone soil vapor extraction (SVE) system at the 200-PW-l OU, which is also located in the Hanford Site's 200 West Area.
Date: November 26, 2007
Partner: UNT Libraries Government Documents Department

Activated carbon testing for the 200 area effluent treatment facility

Description: This report documents pilot and laboratory scale testing of activated carbon for use in the 200 Area Effluent Treatment Facility peroxide decomposer columns. Recommendations are made concerning column operating conditions and hardware design, the optimum type of carbon for use in the plant, and possible further studies.
Date: January 17, 1997
Creator: Wagner, R.N.
Partner: UNT Libraries Government Documents Department

Ozone Removal by Filters Containing Activated Carbon: A Pilot Study

Description: This study evaluated the ozone removal performance of moderate-cost particle filters containing activated carbon when installed in a commercial building heating, ventilating, and air conditioning (HVAC) system. Filters containing 300 g of activated carbon per 0.09 m2 of filter face area were installed in two 'experimental' filter banks within an office building located in Sacramento, CA. The ozone removal performance of the filters was assessed through periodic measurements of ozone concentrations in the air upstream and downstream of the filters. Ozone concentrations were also measured upstream and downstream of a 'reference' filter bank containing filters without any activated carbon. The filter banks with prefilters containing activated carbon were removing 60percent to 70percent of the ozone 67 and 81 days after filter installation. In contrast, there was negligible ozone removal by the reference filter bank without activated carbon.
Date: September 1, 2009
Creator: Fisk, William; Spears, Mike; Sullivan, Douglas & Mendell, Mark
Partner: UNT Libraries Government Documents Department

Dual alkali approaches for the capture and separation of CO{sub 2}

Description: The Solvay process utilizes two alkalis in sequential order to convert CO{sub 2} to sodium carbonate for commercial use. The ability to transform CO{sub 2} into sodium carbonate cost-effectively would be a breakthrough in CO{sub 2} sequestration by providing benign long-term storage of CO{sub 2}. However, the Solvay process was not designed for CO{sub 2} sequestration and is not practical for use in the sequestration of CO{sub 2} from fossil fuel power plants. This paper investigates methods to modify the process in order to make it effective for the control of power plant CO{sub 2} emissions. The new modified process, called the Dual Alkali Approach, attempts to replace either or both bases, ammonia and lime, in the Solvay process with other compounds to make CO{sub 2} capture and separation efficient. Ammonia was replaced with different amines in aqueous solutions of salts and it was found that bicarbonate precipitation did occur. A method to regenerate the amine in the second step has not been implemented. However, the second step in Solvay Process has been implemented without using lime, namely, ammonia has been regenerated from an ammonium chloride solution using activated carbon. The HCl adsorbed in the activated carbon was removed by water to regenerate the activated carbon.
Date: April 4, 2000
Creator: Huang, H. P.; Shi, Y.; Li, W. & Chang, S. G.
Partner: UNT Libraries Government Documents Department


Description: Wood, coke, and coconut-shell charcoals were evaluated for fluorine entrapment. The coconut-shell charcoal produced the smallest amount of solid and liquid reaction products. Efficient removal of fluorine was accomplished by the coconut-shell charcoal in a 5-in.-diameter reactor with a feed containing 25% fluorine at flow rates from 100 to 400 scfh and reactor-wall temperatures of 1200 to 1800 deg F. (C.J.G.)
Date: July 26, 1960
Creator: Houston, N.W.
Partner: UNT Libraries Government Documents Department


Description: Long-term demonstration tests of advanced sorbent enhancement additive (SEA) technologies have been completed at five coal-fired power plants. The targeted removal rate was 90% from baseline conditions at all five stations. The plants included Hawthorn Unit 5, Mill Creek Unit 4, San Miguel Unit 1, Centralia Unit 2, and Hoot Lake Unit 2. The materials tested included powdered activated carbon, treated carbon, scrubber additives, and SEAs. In only one case (San Miguel) was >90% removal not attainable. The reemission of mercury from the scrubber at this facility prevented >90% capture.
Date: May 27, 2011
Creator: Laumb, Jason D.; Laudal, Dennis L.; Dunham, Grant E.; Kay, John P.; Martin, Christopher L.; Thompson, Jeffrey S. et al.
Partner: UNT Libraries Government Documents Department


Description: A fabrication facility with related process equipment has been constructed to fabricate fuel rods containing /sup 233/U and thorium oxide by the bulk oxide-vibratory compaction route and is now in operation at the Oak Ridge National Laboratory. While the initial motivation for the facility was to fabricate /sup 233/U-bearing 1/2-in.-dia x 46-in.-long Zircaloy-2 clad fuel rods for criticality experiments at the Brookhaven National Laboratory, sufficient flexibility has been incorporated into the facility to accommodate a variety of development work on a pilot-plant scale. The facility consists of a number of permanent alpha-tight cubicles which are shielded with 41/4-in. steel. The fabrication process is carried out remotely in these cubicles with the exception of several gloved-hand operations which occur where the dexterity required for manipulation exceeds that of the remote castle-type tongs. The fabrication equipment that has been installed in the facility performs the operations associated with oxide powder comminution and classification, vibratory compaction of oxide in fuel tubes, tube closure, fuel rod decontamination, and fuel rod inspection. Both the facility and the process equipment are described in detail, and detailed assembly drawings of the process equipment are included. (auth)
Date: April 1, 1964
Creator: Sease, J.D.; Lotts, A.L. & Davis, F.C.
Partner: UNT Libraries Government Documents Department

The Adsorption Of Uranium From Solutions By Activated Carbon

Description: Experimental results on the adsorption of U from solutions by activated C indicate that low pH values reduce the adsorption and that a marked change occurs in the adsorption of U(VI) at pH2. Under a given set of conditions the adsorption of U follows a typical Freundlich isotherm. The particle size of the charcoal affects the rate of adsorption but not the amount of U adsorbed at equilibrium. The temperature coefficient of adsorption is negligible, and the adsorption of U from uranyl solutions is a reversible process. (BJH)
Date: August 15, 1949
Creator: Goodrich, J.C.
Partner: UNT Libraries Government Documents Department


Description: A method of predicting the performance of fission gas adsorption traps containing activated charcoal is presented. This method is applied in the evaluation of the fission gas traps designed for use in the ORNL-MTR44 loop experiment. The method should also be applicable in evaluating fission gas traps contained in other reactor experiments. (auth)
Date: July 18, 1958
Creator: Adams, R.E. & Browning, W.E.
Partner: UNT Libraries Government Documents Department


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

THE FACILITY 350 HELIUM-ATMOSPHERE SYSTEM. Final Report, Metallurgy Division Program 1.5.5

Description: The He atmosphere system in Argonne's Facility 350 is described in detail. The system is straightforward, employing drying and carbon towers for the removal of moisture, oxygen, and other impurities. The bulk of the 15,000 ft/ sup 3/ of He atmosphere is continuously recirculated at nearly atmospheric pressure. Purification is accomplished at 140 psig on a portion of the gas that is passed through the drying tower at room temperature and the carbon towers at -- 46 deg C (--50 deg F). The operation is continuous, requiring a minimum of maintenance and operational manpower. The He atmosphere is supplied to the glove- boxes with impurity levels below 3,000 ppm nitrogen, 1,000 ppm oxygen, and 50 ppm moisture. Such purity levels prevent oxidation and combustion of the Pu materials being processed. Experimental data concerning the adsorption of oxygen from He by activated carbon over a range of temperature and pressure conditions are reported. (auth)
Date: December 1, 1962
Creator: Mayfield, R.M.; Tope, W.G. & Shuck, A.B.
Partner: UNT Libraries Government Documents Department


Description: A device for purifying and recycling the helium atmosphere of two dry boxes having a combined volume of 50 ft/sup 3/ is described. Trace impurities are removed by passing the helium through a palladium-catalyst container and a molec ular sieve bed and cooling to - 195 deg C before passing through an activated charcoal bed. Flow rates of 10 scfm and purity levels are estimated. Regeneration procedures are given. Construction prints and a schematic diagram of the heliumpurification unit are shown. (H.G.G.)
Date: December 1, 1962
Creator: Foster, M.S.; Johnson, C.E. & Crouthamel, C.E.
Partner: UNT Libraries Government Documents Department

Scalable Fabrication of Natural-Fiber Reinforced Composites with Electromagnetic Interference Shielding Properties by Incorporating Powdered Activated Carbon

Description: This article discusses preparing Kenaf fiber-polyester composites incorporated with powdered activated carbon (PAC) using the vacuum-assisted resin transfer molding(VARTM) process.
Date: November 17, 2015
Creator: Xia, Changlei; Zhang, Shifeng; Ren, Han; Shi, Sheldon Q.; Zhang, Hualiang; Cai, Liping et al.
Partner: UNT College of Engineering

Treatment of Produced Waters Using a Surfactant Modified Zeolite/Vapor Phase Bioreactor System

Description: This report summarizes work performed on this project from April 2005 through September 2005. In previous work, a series of laboratory scale experiments were conducted to determine the feasibility of using a SMZ system coupled with a VPB to remove and ultimately destroy the organic pollutants found in produced water. Based on the laboratory scale data, a field test of the process was conducted at the McGrath Salt Water Disposal facility in July and August of 2005. The system performed well over repeated feed and regeneration cycles demonstrating the viability of the process for long term operation. Of the BTEX components present in the produced water, benzene had the lowest adsorption affinity for the SMZ and thus controlled the sorption cycle length. Regeneration of the SMZ using air sparging was found to be sufficient in the field to maintain the SMZ adsorption capacity and to allow continuous operation of the system. As expected, the BTEX concentrations in the regeneration off gas stream were initially very high in a given regeneration cycle. However, a granular activated carbon buffering column placed upstream of the VPB reduced the peak BTEX concentrations to acceptable levels for the VPB. In this way, the VPB was able to maintain stable performance over the entire SMZ regeneration period despite the intermittent nature of the feed.
Date: September 11, 2005
Creator: Kwon, Soondong; Darby, Elaine B.; Chen, Li-Jung; Katz, Lynn E.; Kinney, Kerry A.; Bowman, R. S. et al.
Partner: UNT Libraries Government Documents Department

Treatment of Produced Waters Using a Surfactant Modified Zeolite/Vapor Phase Bioreactor System

Description: This report summarizes work performed on this project from October 2004 through March 2005. In previous work, a surfactant modified zeolite (SMZ) was shown to be an effective system for removing BTEX contaminants from produced water. Additional work on this project demonstrated that a compost-based biofilter could biodegrade the BTEX contaminants found in the SMZ regeneration waste gas stream. However, it was also determined that the BTEX concentrations in the waste gas stream varied significantly during the regeneration period and the initial BTEX concentrations were too high for the biofilter to handle effectively. A series of experiments were conducted to determine the feasibility of using a passive adsorption column placed upstream of the biofilter to attenuate the peak gas-phase VOC concentrations delivered to the biofilter during the SMZ regeneration process. In preparation for the field test of the SMZ/VPB treatment system in New Mexico, a pilot-scale SMZ system was also designed and constructed during this reporting period. Finally, a cost and feasibility analysis was also completed. To investigate the merits of the passive buffering system during SMZ regeneration, two adsorbents, SMZ and granular activated carbon (GAC) were investigated in flow-through laboratory-scale columns to determine their capacity to handle steady and unsteady VOC feed conditions. When subjected to a toluene-contaminated air stream, the column containing SMZ reduced the peak inlet 1000 ppmv toluene concentration to 630 ppmv at a 10 second contact time. This level of buffering was insufficient to ensure complete removal in the downstream biofilter and the contact time was longer than desired. For this reason, using SMZ as a passive buffering system for the gas phase contaminants was not pursued further. In contrast to the SMZ results, GAC was found to be an effective adsorbent to handle the peak contaminant concentrations that occur early during the SMZ regeneration ...
Date: March 11, 2005
Creator: Kwon, Soondong; Darby, Elaine B.; Chen, Li-Jung; Katz, Lynn E.; Kinney, Kerry A.; Bowman, R. S. et al.
Partner: UNT Libraries Government Documents Department

Platinum Catalyzed Decomposition of Activated Carbon: 1. Initial Studies

Description: Carbon is an important support for heterogeneous catalysts, such as platinum supported on activated carbon (AC). An important property of these catalysts is that they decompose upon heating in air. Consequently, Pt/AC catalysts can be used in applications requiring rapid decomposition of a material, leaving little residue. This report describes the catalytic effects of platinum on carbon decomposition in an attempt to maximize decomposition rates. Catalysts were prepared by impregnating the AC with two different Pt precursors, Pt(NH{sub 3}){sub 4}(NO{sub 3}){sub 2} and H{sub 2}PtCl{sub 6}. Some catalysts were treated in flowing N{sub 2} or H{sub 2} at elevated temperatures to decompose the Pt precursor. The catalysts were analyzed for weight loss in air at temperatures ranging from 375 to 450 C, using thermogravimetric analysis (TGA). The following results were obtained: (1) Pt/AC decomposes much faster than pure carbon; (2) treatment of the as-prepared 1% Pt/AC samples in N{sub 2} or H{sub 2} enhances decomposition; (3) autocatalytic behavior is observed for 1% Pt/AC samples at temperatures {ge} 425 C; (4) oxygen is needed for decomposition to occur. Overall, the Pt/AC catalyst with the highest activity was impregnated with H{sub 2}PtCl{sub 6} dissolved in acetone, and then treated in H{sub 2}. However, further research and development should produce a more active Pt/AC material.
Date: December 1, 2001
Partner: UNT Libraries Government Documents Department

Solution-reactor-produced Mo-99 using activated carbon to remore I-131

Description: The production of {sup 99}Mo in a solution reactor was explored. Activated charcoal was used to filter the {sup 131}I contaminant from an irradiated fuel solution. Gamma spectroscopy confirmed that the activated carbon trapped a significant amount of {sup 131}I, as well as notable amounts of {sup 133}Xe, {sup 105}Rb, and {sup 140}Ba; the carbon trapped a diminutive amount of {sup 99}Mo. The results promote the idea of solution-reactor-produced {sup 99}Mo. Solution reactors are favorable both energetically and environmentally. A solution reactor could provide enough {sup 99}Mo/{sup 99m}Te to support both the current and future radiopharmaceutical needs of the U.S.
Date: June 1, 1998
Creator: Kitten, S. & Cappiello, C.
Partner: UNT Libraries Government Documents Department