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Description: A number of organisms have been examined for their ability to produce electron-spin-resonance signals at low temperatures in response to illumination. The efficiency of the response is of the order of not less than 5%, and the wavelength for maximum response is generally slightly on the longer side of the wavelength of maximum absorption, with a minimum appearing at the wavelength of maximum absorption.
Date: May 11, 1960
Creator: Sogo, Power B.; Carter, Louise A. & Calvin, Melvin.
Partner: UNT Libraries Government Documents Department

Biocompatible self-assembly of nano-materials for Bio-MEMS and insect reconnaissance.

Description: This report summarizes the development of new biocompatible self-assembly procedures enabling the immobilization of genetically engineered cells in a compact, self-sustaining, remotely addressable sensor platform. We used evaporation induced self-assembly (EISA) to immobilize cells within periodic silica nanostructures, characterized by unimodal pore sizes and pore connectivity, that can be patterned using ink-jet printing or photo patterning. We constructed cell lines for the expression of fluorescent proteins and induced reporter protein expression in immobilized cells. We investigated the role of the abiotic/biotic interface during cell-mediated self-assembly of synthetic materials.
Date: December 1, 2003
Creator: Brozik, Susan Marie; Cesarano, Joseph, III; Brinker, C. Jeffrey; Dunphy, Darren Robert; Sinclair, Michael B.; Manginell, Monica et al.
Partner: UNT Libraries Government Documents Department

Foaming characteristics of refigerant/lubricant mixtures

Description: The air-conditioning and refrigeration industry has moved to HFC refrigerants which have zero ozone depletion and low global warming potential due to regulations on CFC and HCFC refrigerants and concerns for the environment. The change in refrigerants has prompted the switch from mineral oil and alkylbenzene lubricants to polyolester-based lubricants. This change has also brought about a desire for lubricant, refrigerant and compressor manufacturers to understand the foaming properties of alternative refrigerant/ lubricant mixtures, as well as the mechanisms which affect these properties. The objectives of this investigation are to experimentally determine the foaming absorption and desorption rates of HFC and blended refrigerants in polyolester lubricant and to define the characteristics of the foam formed when the refrigerant leaves the refrigerant/ lubricant mixture after being exposed to a pressure drop. The refrigerants being examined include baseline refrigerants: CFC-12 (R-12) and HCFC-22 (R-22); alternative refrigerants: HFC-32 (R-32), R-125, R-134a, and R-143a; and blended refrigerants: R-404A, R-407C, and R-410A. The baseline refrigerants are tested with ISO 32 (Witco 3GS) and ISO 68 (4GS) mineral oils while the alternative and blended refrigerants are tested with two ISO 68 polyolesters (Witco SL68 and ICI RL68H).
Date: April 1, 1997
Creator: Goswami, D.Y.; Shah, D.O.; Jotshi, C.K.; Bhagwat, S.; Leung, M. & Gregory, A.
Partner: UNT Libraries Government Documents Department

Innovative technology summary report: Sealed-seam sack suits

Description: Sealed-seam sack suits are an improved/innovative safety and industrial hygiene technology designed to protect workers from dermal exposure to contamination. Most of these disposable, synthetic-fabric suits are more protective than cotton suits, and are also water-resistant and gas permeable. Some fabrics provide a filter to aerosols, which is important to protection against contamination, while allowing air to pass, increasing comfort level of workers. It is easier to detect body-moisture breakthrough with the disposable suits than with cotton, which is also important to protecting workers from contamination. These suits present a safe and cost-effective (6% to 17% less expensive than the baseline) alternative to traditional protective clothing. This report covers the period from October 1996 to August 1997. During that time, sealed-seam sack suits were demonstrated during daily activities under normal working conditions at the C Reactor and under environmentally controlled conditions at the Los Alamos National Laboratory (LANL).
Date: September 1, 1998
Partner: UNT Libraries Government Documents Department

Synthetic thrombus model for in vitro studies of laser thrombolysis

Description: Laser thrombolysis is the controlled ablation of a thrombus (blood clot) blockage in a living arterial system. Theoretical modeling of the interaction of laser light with thrombi relies on the ability to perform in vitro experiments with well characterized surrogate materials. A synthetic thrombus formulation may offer more accurate results when compared to in vivo clinical experiments. The authors describe the development of new surrogate materials based on formulations incorporating chick egg, guar gum, modified food starch, and a laser light absorbing dye. The sound speed and physical consistency of the materials were very close to porcine (arterial) and human (venous) thrombi. Photographic and videotape recordings of pulsed dye laser ablation experiments under various experimental conditions were used to evaluate the new material as compared to in vitro tests with human (venous) thrombus. The characteristics of ablation and mass removal were similar to that of real thrombi, and therefore provide a more realistic model for in vitro laser thrombolysis when compared to gelatin.
Date: July 1, 1998
Creator: Hermes, R.E. & Trajkovska, K.
Partner: UNT Libraries Government Documents Department

Accelerated degradation studies of MEH-PPV

Description: MEH-PPV, which normally has a reddish color, is well known to show photobleaching problems. The photobleaching can be greatly accelerated by exposure to laser light while in air. For example, shining 457 mn light of relatively low intensity (0.06 W/cm{sup 2}) on the MEH-PPV causes the photoluminescence to decrease by a factor of two within a few seconds of exposure, and to show a nearly complete bleaching of the material within 30 minutes. The degradation rate is strongly influenced by laser power, sample thickness, oxygen exposure during preparation and spinning, as well as the oxygen environment during the measurement. The photobleach is indicative of one class of degradation mechanisms limiting the usefulness of PPV based polymers in electroluminescent devices. MEH-PPV which was spin coated in a nitrogen environment and measured in vacuum showed no measurable photo-chemical degradation for measuring times of up to several hours. A dramatic decrease in PL intensity was observed, however, in the presence of oxygen, as well as in samples spin coated in air, but measured in vacuum. We present data on the PL of MEH-PPV, as a function of oxygen concentration.
Date: July 1, 1995
Creator: Radousky, H.B.; Madden, A.D.; Pakbaz, K.; Hagler, T.W.; Lee, H.W.H.; Lorenzana, H.E. et al.
Partner: UNT Libraries Government Documents Department

Synthetic polymer-layer silicate clay composites

Description: Synthetic hectorites were hydrothermally crystallized with direct incorporation of water-soluble polyvinyl alcohol (PVA), a cationic polymer poly(dimethyl diallyl ammonium chloride) (PDDA), and two cellulosic polymers: hydroxypropyl methylcellulose (HPMC) and hydroxyethyl cellulose (HEC). The molecular weight of polyvinyl alcohols had little effect on the success of hydrothermal hectorite synthesis, d-spacing, or amount of polymer incorporated; the basal spacings range from 19.5 {angstrom} to 20.8 {angstrom} and the percent of polymer incorporated ranges from 20.4 wt% to 23.0 wt%. Synthetic PDDA-hectorite displays the lowest d-spacing at 15.8 {angstrom}, and less cationic PDDA is incorporated into hectorite (7.8 wt% organic) than the other neutral polymers (17.8-23.0 wt% organic). The basal spacing for synthetic HPMC-hectorite is the largest at 25.2 {angstrom}. Small angle neutron scattering was used to further examine the PVA-clay systems.
Date: July 1, 1995
Creator: Carrado, K.A.; Elder, D.L. & Thiyagarajan, P.
Partner: UNT Libraries Government Documents Department

Charge Transport in Synthetic Metals

Description: The phenomenology of charge transport in synthetic metals is reviewed. It is argued that the conventional quasiparticle picture and Boltzmann transport theory do not apply to these materials. The central ideas of Fermi liquid theory are reviewed, and the significant corrections produced by quasiparticle scattering from ferromagnetic spin fluctuations in liquid {sup 3}He are described. It is shown that Sr{sub 2}RuO{sub 4} does not display the symptoms of a nearly-ferromagnetic Fermi liquid, so the source of its odd angular momentum pairing remains to be understood. The solution of an assisted-tunneling model of charge transport in quasi-one dimensional materials is described. This model has a quantum critical point and gives a resistivity that is linear in temperature or frequency, whichever is greater.
Date: January 15, 1999
Creator: Emery, V. J.; Kivelson, S. A. & Muthukumar, V. N.
Partner: UNT Libraries Government Documents Department

Machine tool evaluation (development of environmentally conscious machining fluids and systems). CRADA final report

Description: The overall purpose of this CRADA is to select or develop as required a group of cutting fluids, for use with metals and/or ceramic materials, which are more environmentally benign and which will reduce or eliminate the environmental problems associated with management and disposal of these cutting fluids. This CRADA was initially funded by DOE/DP, and was expanded to include DOE/ER funding with an added focus on environmental issues related to synthetic cutting fluids. The specific objective of this DOE-ER funded project (one of ten technical tasks within the CRADA) is to determine and demonstrate chemical methods of degrading and/or improving the disposability of synthetic cutting fluids. Photochemical advanced oxidation processes were developed and demonstrated to successfully remove all carbon from new and used cutting fluids, and from surrogate solutions containing up to 15,000 ppm of total organic carbon in the initial solutions. Chemical and energy costs for the process were evaluated. Commercial providers of advanced oxidation process technologies were consulted concerning scale-up, and associated costs in industrial systems were estimated to be well represented by the laboratory bench-scale measured values. Engineering aspects and alternative oxidation methodologies were explored through consultation with an internationally recognized chemical engineer, and it was concluded that no clear alternatives were available for treating aqueous fluids with extremely high initial carbon content (i.e., 15,000 popm total organic carbon).
Date: August 1, 1998
Creator: Buchanan, A.C. III; Sigman, M.E. & Yang, C.L.
Partner: UNT Libraries Government Documents Department

Synthetic drilling fluids - a pollution prevention opportunity for the oil and gas industry

Description: Offshore oil and gas operators use specialized drilling fluids, referred to as {open_quotes}muds,{close_quotes} to help maintain well control and to remove drill cuttings from the hole. Historically, either water-based muds (WBMs) or oil-based muds (OBMs) have been used for offshore wells. Recently, the drilling industry has developed several types of synthetic-based muds (SBMs) that combine the desirable operating qualities of OBMs with the lower toxicity and environmental impact qualities of WBMs. This report describes the operational, environmental, and economic features of all three types of muds and discusses potential EPA regulatory barriers to wider use of SBMs.
Date: December 31, 1995
Creator: Veil, J.A.; Burke, C.J. & Moses, D.O.
Partner: UNT Libraries Government Documents Department

Carbon Dioxide Sequestration by Mechanochemical Carbonation of Mineral Silicates

Description: The University of Utah and the University of Idaho investigated the carbonation of silicate minerals by mechanochemical processing. This method uses intense grinding, and has the potential of being much less expensive than other methods of mineral sequestration. Tests were conducted in three types of grinding devices. In these tests, natural and synthetic silicate compounds were ground for varying times in the presence of gaseous CO{sub 2}. A significant change takes place in the lizardite variety of serpentine after 15 to 20 minutes of intense grinding in the presence of gaseous CO{sub 2}. The X-ray diffraction spectrum of lizardite thus treated was much different than that of the untreated mineral. This spectrum could not be identified as that of any natural or synthetic material. Laboratory analyses showed that small amounts of carbon are fixed by grinding lizardite, forsterite, and wollastonite (all naturally-occurring minerals), and synthetic magnesium silicate, in the presence of gaseous CO{sub 2}. It was thus concluded that further investigation was warranted, and a follow-up proposal was submitted to the Department of Energy under solicitation number.
Date: April 1, 2004
Creator: Nelson, Michael G.
Partner: UNT Libraries Government Documents Department

Assembly and actuation of nanomaterials using active biomolecules.

Description: The formation and functions of living materials and organisms are fundamentally different from those of synthetic materials and devices. Synthetic materials tend to have static structures, and are not capable of adapting to the functional needs of changing environments. In contrast, living systems utilize energy to create, heal, reconfigure, and dismantle materials in a dynamic, non-equilibrium fashion. The overall goal of the project was to organize and reconfigure functional assemblies of nanoparticles using strategies that mimic those found in living systems. Active assembly of nanostructures was studied using active biomolecules to drive the organization and assembly of nanocomposite materials. In this system, kinesin motor proteins and microtubules were used to direct the transport and interactions of nanoparticles at synthetic interfaces. In addition, the kinesin/microtubule transport system was used to actively assemble nanocomposite materials capable of storing significant elastic energy. Novel biophysical measurement tools were also developed for measuring the collective force generated by kinesin motor proteins, which will provide insight on the mechanical constraints of active assembly processes. Responsive reconfiguration of nanostructures was studied in terms of using active biomolecules to mediate the optical properties of quantum dot (QD) arrays through modulation of inter-particle spacing and associated energy transfer interaction. Design rules for kinesin-based transport of a wide range of nanoscale cargo (e.g., nanocrystal quantum dots, micron-sized polymer spheres) were developed. Three-dimensional microtubule organizing centers were assembled in which the polar orientation of the microtubules was controlled by a multi-staged assembly process. Overall, a number of enabling technologies were developed over the course of this project, and will drive the exploitation of energy-driven processes to regulate the assembly, disassembly, and dynamic reorganization of nanomaterials.
Date: November 1, 2005
Creator: Spoerke, Erik David; Thayer, Gayle Echo; de Boer, Maarten Pieter; Bunker, Bruce Conrad; Liu, Jun; Corwin, Alex David et al.
Partner: UNT Libraries Government Documents Department

Patterning quantum dot arrays using DNA replication principles.

Description: The convergence of nanoscience and biotechnology has opened the door to the integration of a wide range of biological molecules and processes with synthetic materials and devices. A primary biomolecule of interest has been DNA based upon its role as information storage in living systems, as well as its ability to withstand a wide range of environmental conditions. DNA also offers unique chemistries and interacts with a range of biomolecules, making it an ideal component in biological sensor applications. The primary goal of this project was to develop methods that utilize in vitro DNA synthesis to provide spatial localization of nanocrystal quantum dots (nQDs). To accomplish this goal, three specific technical objectives were addressed: (1) attachment of nQDs to DNA nucleotides, (2) demonstrating the synthesis of nQD-DNA strands in bulk solution, and (3) optimizing the ratio of unlabeled to nQD-labeled nucleotides. DNA nucleotides were successfully attached to nQDs using the biotin-streptavidin linkage. Synthesis of 450-nm long, nQD-coated DNA strands was demonstrated using a DNA template and the polymerase chain reaction (PCR)-based method of DNA amplification. Modifications in the synthesis process and conditions were subsequently used to synthesize 2-{micro}m long linear nQD-DNA assemblies. In the case of the 2-{micro}m structures, both the ratio of streptavidin-coated nQDs to biotinylated dCTP, and streptavidin-coated nQD-dCTPs to unlabeled dCTPs affected the ability to synthesize the nQD-DNA assemblies. Overall, these proof-of-principles experiments demonstrated the successful synthesis of nQD-DNA using DNA templates and in vitro replication technologies. Continued development of this technology may enable rapid, spatial patterning of semiconductor nanoparticles with Angstrom-level resolution, as well as optically active probes for DNA and other biomolecular analyses.
Date: November 1, 2004
Creator: Crown, Kevin K. & Bachand, George David
Partner: UNT Libraries Government Documents Department

Simulated Waste for Leaching and Filtration Studies--Laboratory Preparation Procedure

Description: This report discusses the simulant preparation procedure for producing multi-component simulants for leaching and filtration studies, including development and comparison activities in accordance with the test plan( ) prepared and approved in response to the Test Specification 24590-WTP-TSP-RT-06-006, Rev 0 (Smith 2006). A fundamental premise is that this approach would allow blending of the different components to simulate a wide variety of feeds to be treated in the Hanford Tank Waste Treatment and Immobilization Plant (WTP). For example, a given feed from the planned feed vector could be selected, and the appropriate components would then be blended to achieve a representation of that particular feed. Using the blending of component simulants allows the representation of a much broader spectrum of potential feeds to the Pretreatment Engineering Platform (PEP).
Date: October 27, 2009
Creator: Smith, Harry D.; Russell, Renee L. & Peterson, Reid A.
Partner: UNT Libraries Government Documents Department

Results of Aging Tests of Vendor-Produced Blended Feed Simulant

Description: The Hanford Tank Waste Treatment and Immobilization Plant (WTP) is procuring through Pacific Northwest National Laboratory (PNNL) a minimum of five 3,500 gallon batches of waste simulant for Phase 1 testing in the Pretreatment Engineering Platform (PEP). To make sure that the quality of the simulant is acceptable, the production method was scaled up starting from laboratory-prepared simulant through 15-gallon vendor prepared simulant and 250-gallon vendor prepared simulant before embarking on the production of the 3500-gallon simulant batch by the vendor. The 3500-gallon PEP simulant batches were packaged in 250-gallon high molecular weight polyethylene totes at NOAH Technologies. The simulant was stored in an environmentally controlled environment at NOAH Technologies within their warehouse before blending or shipping. For the 15-gallon, 250-gallon, and 3500-gallon batch 0, the simulant was shipped in ambient temperature trucks with shipment requiring nominally 3 days. The 3500-gallon batch 1 traveled in a 70-75°F temperature controlled truck. Typically the simulant was uploaded in a PEP receiving tank within 24-hours of receipt. The first uploading required longer with it stored outside. Physical and chemical characterization of the 250-gallon batch was necessary to determine the effect of aging on the simulant in transit from the vendor and in storage before its use in the PEP. Therefore, aging tests were conducted on the 250-gallon batch of the vendor-produced PEP blended feed simulant to identify and determine any changes to the physical characteristics of the simulant when in storage. The supernate was also chemically characterized. Four aging scenarios for the vendor-produced blended simulant were studied: 1) stored outside in a 250-gallon tote, 2) stored inside in a gallon plastic bottle, 3) stored inside in a well mixed 5-L tank, and 4) subject to extended temperature cycling under summer temperature conditions in a gallon plastic bottle. The following series of aging tests ...
Date: April 21, 2009
Creator: Russell, Renee L.; Buchmiller, William C.; Cantrell, Kirk J.; Peterson, Reid A. & Rinehart, Donald E.
Partner: UNT Libraries Government Documents Department


Description: The Savannah River National Laboratory (SRNL), under the Department of Energy (DOE) Office of Environmental Management (EM), is modifying and testing the SpinTek{trademark} rotary microfilter (RMF) for radioactive filtration service in the Department of Energy (DOE) complex. The RMF has been shown to improve filtration throughput when compared to other conventional methods such as cross-flow filtration. A concern with the RMF was that backpressure, or reverse flow through the disk, would damage the filter membranes. Reverse flow might happen as a result of an inadvertent valve alignment during flushing. Testing was completed in the Engineering Development Laboratory (EDL) located in SRNL to study the physical effects of backpressure as well as to determine the maximum allowable back-pressure for RMF disks. The RMF disks tested at the EDL were manufactured by SpinTek{trademark} Filtration and used a Pall Corporation PMM050 filter membrane (0.5 micron nominal pore size) made from 316L stainless steel. Early versions of the RMF disks were made from synthetic materials that were incompatible with caustic solutions and radioactive service as well as being susceptible to delaminating when subjected to backpressure. Figure 1-1 shows the essential components of the RMF; 3 rotating disks and 3 stationary turbulence promoters (or shear elements) are shown. Figure 1-2 show the assembly view of a 25 disk RMF proposed for use at the Savannah River Site (SRS) and at the Hanford Facility. The purpose of the testing discussed in this report was to determine the allowable backpressure for RMF disks as well as study the physical effects of backpressure on RMF disks made with the Pall PMM050 membrane. This was accomplished by pressurizing the disks in the reverse flow direction (backpressure) until the test limit was reached or until membrane failure occurred. Backpressure was applied to the disks with air while submerged in deionized ...
Date: April 14, 2011
Creator: Fowley, M. & Herman, D.
Partner: UNT Libraries Government Documents Department

Development and Demonstration of Ultrafiltration Simulants

Description: According to Bechtel National, Inc. (BNI) Test Specification 24590-PTF-TSP-RT-06-006, Rev 0, Simulant Development to Support the Development and Demonstration of Leaching and Ultrafiltration Pretreatment Processes,” simulants for boehmite, gibbsite, and filtration are to be developed that can be used in subsequent bench and integrated testing of the leaching/filtration processes for the waste treatment plant (WTP). These simulants will then be used to demonstrate the leaching process and to help refine processing conditions which may impact safety basis considerations (Smith 2006). This report documents the results of the filtration simulant development.
Date: February 24, 2009
Creator: Russell, Renee L.; Billing, Justin M.; Peterson, Reid A.; Rinehart, Donald E. & Smith, Harry D.
Partner: UNT Libraries Government Documents Department

Development and Characterization of Boehmite Component Simulant

Description: According to Bechtel National Inc.’s (BNI’s) Test Specification 24590-PTF-TSP-RT-06-006, Rev 0, “Simulant Development to Support the Development and Demonstration of Leaching and Ultrafiltration Pretreatment Processes,” simulants for boehmite, gibbsite, and filtration are to be developed that can be used in subsequent bench and integrated testing of the leaching/filtration processes. These simulants will then be used to demonstrate the leaching process and to help refine processing conditions that may impact safety basis considerations (Smith 2006). This report documents the results of the boehmite simulant development.
Date: March 10, 2009
Creator: Russell, Renee L.; Peterson, Reid A.; Smith, Harry D.; Rinehart, Donald E.; Aker, Pamela M. & Buck, Edgar C.
Partner: UNT Libraries Government Documents Department

Framework for a comparative environmental assessment of drilling fluids

Description: During the drilling of an oil or gas well, drilling fluid (or mud) is used to maintain well control and to remove drill cuttings from the hole. In response to effluent limitation guidelines promulgated by the US Environmental Protection Agency (EPA) for discharge of drilling wastes offshore, alternatives to water and oil-based muds have been developed. These synthetic-based muds (SBMs) are more efficient than water-based muds (WBMs) for drilling difficult and complex formation intervals and have lower toxicity and smaller environmental impacts than diesel or conventional mineral oil-based muds (OBMs). A third category of drilling fluids, derived from petroleum and called enhanced mineral oils (EMOs), also have these advantages over the traditionally used OBMs and WBMs. EPA recognizes that SBMs and EMOs are new classes of drilling fluids, but their regulatory status is unclear. To address this uncertainty, EPA is following an innovative presumptive rulemaking process that will develop final regulations for SBM discharges offshore in less than three years. This report develops a framework for a comparative risk assessment for the discharge of SBMs and EMOs, to help support a risk-based, integrated approach to regulatory decision making. The framework will help identify potential impacts and benefits associated with the use of SBMs, EMOs, WBMs, and OBMs; identify areas where additional data are needed; and support early decision-making in the absence of complete data. As additional data becomes available, the framework can support a full quantitative comparative assessment. Detailed data are provided to support a comparative assessment in the areas of occupational and public health impacts.
Date: November 1, 1998
Creator: Meinhold, A.F.
Partner: UNT Libraries Government Documents Department

Compatibility of lubricant additives with HFC refrigerants and synthetic lubricants. Final report, Part 1

Description: Part one of this research provides manufacturers of components of air-conditioning and refrigeration equipment with a useful list of lubricant additives, sources, functional properties and chemical species. The list in part one is comprised of domestic lubricant additive suppliers and the results of a literature search that was specifically targeted for additives reported to be useful in polyolester chemistry.
Date: July 1, 1997
Creator: Cavestri, R.C.
Partner: UNT Libraries Government Documents Department

Dosimetry using environmental and biological materials. Final report

Description: This report summarizes a five year effort to improve the sensitivity and reliability of retrospective dosimetry methods, to collaborate with laboratories engaged in related research and to share the technology with startup laboratories seeking similar capabilities. This research program has focused on validation of electron paramagnetic resonance (EPR) as a dosimetry tool and on optimization of the technique by reducing the lower limits of detection, simplifying the process of sample preparation and analysis and speeding analysis to allow greater throughput in routine measurement situations. The authors have investigated the dosimetric signal of hard tissues in enamel, deorganified dentin, synthetic carbonated apatites and synthetic hydroxyapatite. This research has resulted in a total of 27 manuscripts which have been published, are in press, or have been submitted for publication. Of these manuscripts, 14 are included in this report and were indexed separately for inclusion in the data base.
Date: February 1, 1998
Creator: Haskell, E.; Kenner, G. & Hayes, R.
Partner: UNT Libraries Government Documents Department

Mesoporous synthetic clays : synthesis, characterization, and use as HDS catalyst supports.

Description: Mesoporous synthetic clays (MSCs) are obtained when polymer-containing silicate gels are hydrothermally crystallized to form layered magnesium silicate hectorite clays containing polymers that are incorporated in situ. Polyvinylpyrrolidone of several average molecular weights ranging from 10K to 1.3M, in gel loadings varying from 5-30 wt%, were used. The organic polymer template molecules were removed from synthetic polymer-clay complexes via calcination. Pore radii, surface areas, and pore volumes of the resulting porous inorganic networks were then measured. For the most part there is a direct correlation between both PVP molecular weight and polymer loading on the diameter of the average pore. In addition to conventional techniques, the polymer-clay materials were also characterized by small angle x-ray scattering to ascertain the disposition of the polymeric matrix. The MSC materials after calcination were examined as potential supports for hydrodesulfurization (HDS). They were loaded with a bimetallic Co/Mo catalyst system for comparison with a commercial Co/Mo alumina catalyst. Dibenzothiophene (DBT) diluted with hexadecane (0.75 wt% S) was utilized as a liquid feed for the HDS tests. This feed was chosen as a deep HDS test of a heavy model oil. The pore diameters of the MSC catalysts were found to have a strong effect on both the HDS activity and selectivity.
Date: August 10, 1999
Creator: Bloomquist, C. A. A.; Carrado, K. A.; Marshall, C. L.; Seifert, S.; Wei, D. & Xu, L.
Partner: UNT Libraries Government Documents Department