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Biological Production of Ethanol From Coal

Description: The fermentation pH has been observed to be the key parameter affecting the ratio of ethanol to acetate produced by Clostridium ljungdahlii. The effects of controlled pH on cell growth and product formation by C. ljungdahlii were measured. It was found that cell concentration and acetate concentration increased with pH, while the ethanol concentration was highest at the lower pH. The molar product ratio of ethanol to acetate was 0.74 at pH 4.0, 0.39 at pH 4.5 and 0.12 at pH 5.0. Future experime… more
Date: January 1, 1990
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Biological Production of Ethanol From Coal

Description: Research is continuing in an attempt to increase both the ethanol concentration and product ratio using C. ljungdahlii. The purpose of this report is to present data utilizing a medium prepared especially for C. ljungdahlii. Medium development studies are presented, as well as reactor studies with the new medium in batch reactors. CSTRs and CSTRs with cell recycle. The use of this new medium has resulted in significant improvements in cell concentration, ethanol concentration and product ratio.
Date: January 1, 1992
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A novel approach to highly dispersing catalytic materials in coal for gasification

Description: This project seeks to develop a technique, based on coal surface properties, for highly dispersing catalysts in coal for gasification and to investigate the potential of using potassium carbonate and calcium acetate mixtures as catalysts for coal gasification. The lower cost and higher catalytic activity of the latter compound will produce economic benefits by reducing the amount of K{sub 2}CO{sub 3} required for high coal char reactivities.
Date: January 1, 1992
Creator: Abotsi, G.M.K. & Bota, K.B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Biological Production of Ethanol From Coal

Description: A batch kinetic study involving Clostridium lungdahlii in a mineral medium was carried out in order to provide baseline data for the effects of nutrients on product ratio and kinetics. The use of this minimal medium containing vitamins, minerals, select amino acids and salts showed both a lower maximum specific growth rate and a lower maximum specific uptake rate than found when using a complex medium supplemented with 0.01% yeast extract. At the same time, the product ratio was improved slight… more
Date: January 1, 1990
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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LABORATORY DEVELOPMENT OF A CARRIER-PRECIPITATION PROCESS FOR THE RECOVERY OF STRONTIUM FROM PUREX WASTES

Description: Strontium recovery from Purex 1WW was investigated with simulated feeds and tracer activities. Initial experiments demonstrated recovery of over 70% of the strontium by sulfate precipitation from partially neutralized 1WW by either increasing the sulfate concentration to about 3 M or by adding carriers such as lead. Precipitation of iron was avoided by addition of one or more moles of tartrate per two moles of iron. Precipitation at elevated temperatures and addition of lead after pH adjustment… more
Date: May 1, 1961
Creator: Bray, L.A. & Van Tuyl, H.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Biological Production of Ethanol From Coal

Description: Previous results have shown that the yeast extract concentration and the medium pH significantly affect the ratio of ethanol to acetate in the product stream when fermenting CO, CO{sub 2} and H{sub 2} in synthesis gas to products by Clostridium ljungdahlii. Further experimentation has demonstrated the impact of eliminating yeast extract from the medium (except for the slight quantity transferred with the inoculm), especially when coupled with low pH. An ethanol to acetate product ratio of 4.0 w… more
Date: January 1, 1990
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Biological Production of Ethanol From Coal

Description: The effects of temperature on the growth and uptake of CO by C. ljundahlii were studied in batch culture. A maximum specific growth rate of 0.095h{sup {minus}1} was found at 37{degrees}C, a normal optimum temperature for the growth of anaerobic bacteria. A maximum specific uptake rate of 0.0095 mmol/mg{center dot}h was found at a slightly higher temperature of 40{degrees}C. CSTR studies were carried out measuring the effects of agitation rate on culture performance. As expected, growth was best… more
Date: January 1, 1991
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Biological Production of Ethanol From Coal

Description: Previous results have shown that the medium pH, the composition of the medium and concentration of medium constituents significantly affect the ratio of ethanol to acetate in the product stream when fermenting CO, CO{sub 2} and H{sub 2} in synthesis gas to products by Clostridium ljungdahlii. An additional batch study was carried out varying the agitation rate at pH 4, 4.5 and 5.0. It was speculated that increased agitation rates in combination with low pH might result in increased ethanol prod… more
Date: January 1, 1990
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Biological Production of Ethanol Fom Coal

Description: Research is continuing in an attempt to increase both the ethanol concentration and product ratio using C. ljungdahlii. The purpose of this report is to present data (acetate to ethanol) utilizing a medium prepared especially for C. ljungdahlii. Medium development studies are presented, as well as reactor studies with the new medium in batch reactors. Continuous stirred tank reactor (CSTR) with cell recycle. The use of this new medium has resulted in significant improvements in cell concentrati… more
Date: May 1, 1992
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Biological Production of Ethanol From Coal

Description: Research is continuing in attempting to increase both the ethanol concentration and product ratio (acetate to ethanol) from the C. ljungdahlii fermentation. Both batch and continuous reactors are being used for this purpose. The purpose of this report is four-fold. First, the data presented in PETC Report No. 2-4-91 (June--September, 1991) are analyzed and interpreted using normalized specific growth and production rates. This technique eliminates experimental variation due to differences in in… more
Date: May 1, 1992
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Membrane-controlled processes for the energy-efficient conversion of sludges to fuels and marketable chemicals

Description: Studies were carried out on the concentration of primary and secondary sludges by ultrafiltration, and the operation of a membrane-assisted anaerobic digester to treat these sludges. Auxiliary devices including water-spilling and membrane solvent extraction were tested for their feasibility in the ehhancement of digester operations and the recovery of valuable byproducts. It was shown that membrane-facilitated digestion can increase the rate of these processes by a factor of ten, together with … more
Date: March 1, 1982
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Biological Production of Ethanol From Coal

Description: Previously studies have shown the importance of both medium composition and concentration and medium pH on ethanol production of Clostridium ljungdahlii in fermenting CO, CO{sub 2} and H{sub 2} in synthesis gas. Four additional batch experiments involving medium composition and concentration were carried out in modified basal medium without yeast extract at pH 4.0. These experiments indicate that basal medium with only small amounts of B-vitamins can yield significant cell growth while yielding… more
Date: January 1, 1991
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Biological Production of Ethanol From Coal

Description: The effects of temperature on the growth and uptake of CO by C. ljundahlii were studied in batch culture. Continuous stirred tank reactor (CSTR) studies were carried out measuring the effects of agitation rate on culture performance. Finally, cell recycle studies continued in conjunction with a CSTR.
Date: May 1, 1992
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Biological Production of Ethanol From Coal

Description: Two batch and one continuous reactor study involving Clostridium ljungdahlii were carried out. First, the effects of H{sub 2} partial pressure on growth, CO and H{sub 2} uptake and product formation by C. ljungdahlii were investigated in batch culture. Over the concentration range studied, it was observed that CO was preferentially utilized in favor of H{sub 2}. It was also seen that increasing H{sub 2} partial pressures increased the ratio of ethanol to acetate. Finally, a two-stage CSTR syste… more
Date: January 1, 1989
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Biological Production of Ethanol From Coal

Description: Research is continuing in attempting to increase both the ethanol concentration and product ratio from the C. ljungdahlii fermentation. Both batch and continuous reactors are being used for this purpose. The purpose of this report is four-fold. First, the data presented in PETC Report No. 2-4-91 (June--September 1991) are analyzed and interpreted using normalized specific growth and production rates. This technique eliminates experimental variation due to the differences in inoculum history. Se… more
Date: January 1, 1991
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Molecular mechanisms of the epithelial transport of toxic metal ions, particularly mercury, cadmium, lead, arsenic, zinc, and copper. Progress report, January 1, 1979-December 31, 1979. [Ca; Pb; cockerels]

Description: The mechanism of lead transport is presented, and especially the particular similarities or dissimilarities between lead and calcium in this process. The absorption of these metals was determined cockerels, raised on a commercial diet or on a specified diet, using in vivo ligated loop procedure. The dose administered into the loop contained 0.5 ..mu..Ci /sup 203/Pb (and/or 0.1 ..mu..Ci /sup 47/Ca), and 0.01 mM lead acetate (and/or mM CaCl/sub 2/) in 0.5 ml 0.15 M NaCl,pH 6.5. It was shown that … more
Date: January 1, 1979
Creator: Wasserman, R H
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effects of calcium magnesium acetate on the combustion of coal-water slurries

Description: The general objective of the project is to investigate the combustion behavior of single and multiple Coal-Water Fuel (CWF) particles burning at high temperature environments. Both uncatalyzed as well as catalyzed CWF drops with Calcium Magnesium Acetate (CMA) catalyst will be investigated. Emphasis will also be given in the effects of CMA on the sulfur capture during combustion. To help achieve these objectives the following project tasks were carried over this 7th three-month period: (1) Rede… more
Date: January 1, 1991
Creator: Levendis, Y.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Investigation of test methods, material properties, and processes for solar cell encapsulants. Seventh annual report

Description: The goal of the program is to identify and evaluate encapsulation materials and processes for the protection of silicon solar cells for service in a terrestrial environment. Aging and degradation studies were performed including: thermal aging, sunlamp exposures, aging in controlled environment reactors and outdoor photothermal aging devices, and metal catalyzed degradation. Other tests addressed water absorption, primers and adhesives, soiling experiments, and corrosion protection. (LEW)
Date: January 1, 1983
Creator: Willis, P. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Microbiological, Geochemical and Hydrologic Processes Controlling Uranium Mobility: An Integrated Field-Scale Subsurface Research Challenge Site at Rifle, Colorado, Quality Assurance Project Plan

Description: The U.S. Department of Energy (DOE) is cleaning up and/or monitoring large, dilute plumes contaminated by metals, such as uranium and chromium, whose mobility and solubility change with redox status. Field-scale experiments with acetate as the electron donor have stimulated metal-reducing bacteria to effectively remove uranium [U(VI)] from groundwater at the Uranium Mill Tailings Site in Rifle, Colorado. The Pacific Northwest National Laboratory and a multidisciplinary team of national laborato… more
Date: January 7, 2008
Creator: Fix, N. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Novel imaging techniques, integrated with mineralogical, geochemical and microbiological characterizations to determine the biogeochemical controls on technetium mobility in FRC sediments

Description: The objective of this research program was to take a highly multidisciplinary approach to define the biogeochemical factors that control technetium (Tc) mobility in FRC sediments. The aim was to use batch and column studies to probe the biogeochemical conditions that control the mobility of Tc at the FRC. Background sediment samples from Area 2 (pH 6.5, low nitrate, low {sup 99}Tc) and Area 3 (pH 3.5, high nitrate, relatively high {sup 99}Tc) of the FRC were selected (http://www.esd.ornl.gov/na… more
Date: February 3, 2009
Creator: Lloyd, Jonathan R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of Superior Sorbents for Separation of CO2 from Flue Gas at a Wide Temperature Range During Coal Combustion

Description: In chapter 1, the studies focused on the development of novel sorbents for reducing the carbon dioxide emissions at high temperatures. Our studies focused on cesium doped CaO sorbents with respect to other major flue gas compounds in a wide temperature range. The thermo-gravimetric analysis of sorbents with loadings of CaO doped on 20 wt% cesium demonstrated high CO{sub 2} sorption uptakes (up to 66 wt% CO{sub 2}/sorbent). It is remarkable to note that zero adsorption affinity for N{sub 2}, O{s… more
Date: June 30, 2007
Creator: Smirniotis, Panagiotis G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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