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Final Technical Report - Autothermal Styrene Manufacturing Process with Net Export of Energy

Description: The overall objectives of the project were to: (a) develop an economically competitive processing technology for styrene monomer (SM) that would reduce process energy requirements by a minimum 25% relative to those of conventional technology while achieving a minimum 10% ROI; and (b) advance the technology towards commercial readiness. This technology is referred to as OMT (Oxymethylation of Toluene). The unique energy savings feature of the OMT technology would be replacement of the conventional benzene and ethylene feedstocks with toluene, methane in natural gas and air or oxygen, the latter of which have much lower specific energy of production values. As an oxidative technology, OMT is a net energy exporter rather than a net energy consumer like the conventional ethylbenzene/styrene (EB/SM) process. OMT plants would ultimately reduce the cost of styrene monomer which in turn will decrease the costs of polystyrene making it perhaps more cost competitive with competing polymers such as polypropylene.
Date: November 29, 2011
Creator: Trubac, Robert , E.; Lin, Feng & Ghosh, Ruma: Greene, Marvin
Partner: UNT Libraries Government Documents Department

Value of Coproduction of Ethanol and Furfural from Acid Hydrolysis Processes

Description: In the acid hydrolysis of a cellulosic feedstock (wood, wood wastes, or crop residues), up to 3.65 lb of furfural may be coproduced with each gallon of ethanol for only the cost of recovering and purifying it. Each plant producing 50 x 106 gal/yr of ethanol would produce an amount of by-product furfural equal to the total current domestic production. Thus, the need arises for investigation into potentially suitable processes for deriving profitable end products from furfural and thus expanding the market. The objectives of this study were to determine the economic potential of five selected, large volume derivatives of furfural that could displace hydrocarbon-based chemicals, and the consequent value of furfural as a by-product to the cellulose hydrolysis process of ethanol production.
Date: May 1, 1984
Creator: Parker, S.; Calnon, M.; Feinberg, D.; Power, A. & Weiss, L.
Partner: UNT Libraries Government Documents Department

Toward Accurate Reaction Energetics for Molecular Line Growth at Surface: Quantum Monte Carlo and Density Functional Theory Calculations

Description: We revisit the molecular line growth mechanism of styrene on the hydrogenated Si(001) 2x1 surface. In particular, we investigate the energetics of the radical chain reaction mechanism by means of diffusion quantum Monte Carlo (QMC) and density functional theory (DFT) calculations. For the exchange correlation (XC) functional we use the non-empirical generalized-gradient approximation (GGA) and meta-GGA. We find that the QMC result also predicts the intra dimer-row growth of the molecular line over the inter dimer-row growth, supporting the conclusion based on DFT results. However, the absolute magnitudes of the adsorption and reaction energies, and the heights of the energy barriers differ considerably between the QMC and DFT with the GGA/meta-GGA XC functionals.
Date: October 14, 2009
Creator: Kanai, Y & Takeuchi, N
Partner: UNT Libraries Government Documents Department

HYDROTHERMALLY SELF-ADVANCING HYBRID COATINGS FOR MITIGATING CORROSION OF CARBON STEEL.

Description: Hydrothermally self-advancing hybrid coatings were prepared by blending two starting materials, water-borne styrene acrylic latex (SAL) as the matrix and calcium aluminate cement (CAC) as the hydraulic filler, and then their usefulness was evaluated as the room temperature curable anti-corrosion coatings for carbon steel in CO{sub 2}-laden geothermal environments at 250 C. The following two major factors supported the self-improving mechanisms of the coating during its exposure in an autoclave: First was the formation of a high temperature stable polymer structure of Ca-complexed carboxylate groups containing SAL (Ca-CCG-SAL) due to hydrothermal reactions between SAL and CAC; second was the growth with continuing exposure time of crystalline calcite and boehmite phases coexisting with Ca-CCG-SAL. These two factors promoted the conversion of the porous microstructure in the non-autoclaved coating into a densified one after 7 days exposure. The densified microstructure not only considerably reduced the conductivity of corrosive ionic electrolytes through the coatings' layers, but also contributed to the excellent adherence of the coating to underlying steel' s surface that, in turn, retarded the cathodic oxygen reduction reaction at the corrosion site of steel. Such characteristics including the minimum uptake of corrosive electrolytes by the coating and the retardation of the cathodic corrosion reaction played an important role in inhibiting the corrosion of carbon steel in geothermal environments.
Date: November 22, 2006
Creator: SUGAMA, T.
Partner: UNT Libraries Government Documents Department

Microbial engineering of nano-heterostructures; biological synthesis of a magnetically-recoverable palladium nanocatalyst

Description: Precious metals supported on ferrimagnetic particles form a diverse range of catalysts. Here we show a novel biotechnological route for the synthesis of a heterogeneous catalyst consisting of reactive palladium nanoparticles arrayed on a biomagnetite support. The magnetic support was synthesized at ambient temperature by the Fe(III)-reducing bacterium, Geobacter sulfurreducens, and facilitated ease of recovery of the catalyst with superior performance due to reduced agglomeration. Arrays of palladium nanoparticles were deposited on the nanomagnetite using a simple one-step method without the need to modify the biomineral surface most likely due to an organic coating priming the surface for Pd adsorption. A combination of EXAFS and XPS showed the particles to be predominantly metallic in nature. The Pd{sup 0}-biomagnetite was tested for catalytic activity in the Heck Reaction coupling iodobenzene to ethyl acrylate or styrene and near complete conversion to ethyl cinnamate or stilbene was achieved within 90 and 180 min, respectively.
Date: December 1, 2009
Creator: Coker, V. S.; Bennett, J. A.; Telling, N.; Charnock, J. M.; van der Laan, G.; Pattrick, R. A. D. et al.
Partner: UNT Libraries Government Documents Department

Novel CO{sub 2}-thickeners for improved mobility control

Description: The objective of this study was to design, synthesize, and characterize thickening agents for dense carbon dioxide and to evaluate their solubility and viscosity-enhancing potential in CO{sub 2}. Hydrocarbon-fluorocarbon random copolymers, sulfonated hydrocarbon-fluorocarbon random copolymers, semifluorinated trialkyltin fluorides and small hydrogen-bonding compounds have been evaluated. Random copolymers of styrene and heptadecafluorodecyl acrylate yielded substantial increases in viscosity. Falling cylinder viscometry results indicated that the 29%styrene--71%fluoroacrylate bulk-polymerized copolymer induced very significant viscosity increases at copolymer concentrations of 0.1--5.0wt%.
Date: February 2, 2000
Creator: Enick, Dr. Robert M.; Beckman, Dr. Eric J. & Hamilton, Dr. Andrew
Partner: UNT Libraries Government Documents Department

Novel CO{sub 2}-thickeners for improved mobility control

Description: The objective of this study was to design, synthesize, and characterize thickening agents for dense carbon dioxide and to evaluate their solubility and viscosity-enhancing potential in CO{sub 2}. Previously, hydrocarbon-fluorocarbon random copolymers, sulfated hydrocarbon-fluorocarbon random copolymers, semifluorinated trialkyltin fluorides and small hydrogen-bonding compounds were evaluated. Random copolymers of styrene and heptadecafluorodecyl acrylate yielded substantial increases in viscosity. The amount of styrene varied between 22--40 mole% in the copolymer. Falling cylinder viscometry results indicated that the 29% styrene--71% fluoroacrylate copolymer induced (at 295K and 34.5 Mpa) increases of 10, 60 and 250 at copolymer concentrations of 1, 3 and 5wt%, respectively.
Date: February 2, 2000
Creator: Enick, Dr. Robert M.; Beckman, Dr. Eric J. & Hamilton, Dr. Andrew
Partner: UNT Libraries Government Documents Department

Novel CO{sub 2}-thickeners for improved mobility control

Description: The objective of this study was to design, synthesize, and characterize thickening agents for dense carbon dioxide and to evaluate their solubility and viscosity-enhancing potential in CO{sub 2}. Hydrocarbon-fluorocarbon random copolymers, sulfated hydrocarbon-fluorocarbon random copolymers, semifluorinated trialkyltin fluorides and small hydrogen-bonding compounds were evaluated. Random copolymers of styrene and heptadecafluorodecyl acrylate were characterized by high solubility ion dense carbon dioxide and the most substantial increases in solution viscosity. Falling cylinder viscometry results indicated that the 29%styrene--71%fluoroacylate bulk-polymerized copolymer induced 2--250 fold increases in viscosity at copolymer concentrations of 0.2--5.0wt%.
Date: February 2, 2000
Creator: Enick, Robert M.; Beckman, Eric J. & Hamilton, Andrew
Partner: UNT Libraries Government Documents Department

The interactive effects of pH, surface tension, and solution density for flotation systems for separation of equivalent-density materials: separation of ABS from HIPS

Description: This paper presents the results of research being conducted at Argonne National Laboratory, to develop a cost-effective and environmentally acceptable process for the separation of high-value plastics from discarded household appliances. The process under development has separated high-purity (greater than 99.5%) acrylonitrile-butadiene-styrene (ABS) and high-impact polystyrene (HIPS) from commingled plastics generated by appliance-shredding and metal recovery operations. Plastics of similar densities, such as ABS and HIPS are further separated by using a chemical solution. By controlling the surface tension, the density and the temperature of the chemical solution, we are able to selectively float/separate plastics that have equivalent densities. In laboratory-scale tests, this technique has proven highly effective in recovering high-purity plastics materials from discarded household appliances and other obsolete durable goods. A pilot plant is under construction to demonstrate and assess the technical and economic performance of this process. In this paper, we examine the technical and economic issues that affect the recovery and separation of plastics and provide an update on Argonne`s plastics separation research and development activities.
Date: July 1, 1996
Creator: Karvelas, D.E.; Jody, B.J.; Pomykala, J.A. & Daniels, E.J.
Partner: UNT Libraries Government Documents Department

NOVEL CO2-THICKENERS FOR IMPROVED MOBILITY CONTROL

Description: The first carbon dioxide thickeners have been successfully designed. Each thickener is characterized by a highly carbon dioxide-phobic functionality that imparts CO{sub 2}-solubility and a carbon dioxide-phobic group that facilitates viscosity-enhancing intermolecular associations. The design of each thickener required that appropriate balance of these groups to yield a compound that was at least several weight percent soluble in CO{sub 2} and capable of thickening the carbon dioxide by a factor of 2-20. Four types of thickeners were identified, fluoroacrylate-styrene copolymers (polyFAST), fluorinated telechelic ionomers, semi-fluorinated trialkyltin fluorides and small, fluorinated hydrogen-bonding compounds. Although significant viscosity increases (e.g. doubling the viscosity) were evidenced for each thickener during falling cylinder viscometry analysis, the polyFAST thickener provided the most dramatic increases at dilute concentration. PolyFAST is a bulk-polymerized, random copolymer of fluoroacrylate and styrene with a number-average molecular weight of about 500,000. It appears as a white, slightly waxy solid at ambient conditions. The fluoroacrylate enhances the CO{sub 2} solubility, while the styrene promotes intermolecular stacking of the aromatic groups. Although concentrations between 20-29 mol% styrene yield a thickener, the optimal composition of polyFAST for thickening was 29mol% styrene and 71mol% fluoroacrylate. Mobility measurements with a Berea sandstone core indicated that at a superficial velocity of one foot per day, a 0.5wt% concentration of 29%styrene--71%fluoroacrylate polyFAST tripled the viscosity. At concentrations of 1% and 1.5wt%, the CO{sub 2} viscosity increased by a factor of 8 and 19, respectively. If lower proportions of styrene are used, the compound will dissolve more readily in carbon dioxide but the viscosity enhancement will diminish. At higher proportions of styrene, the CO{sub 2} solubility decreases and the thickening capability also decreased, apparently due to the increased number of non-viscosity enhancing intramolecular interactions between the aromatic groups. The high price, environmental persistence, and lack of availability of bulk amounts ...
Date: October 1, 2001
Creator: Enick, Robert M.; Beckman, Eric J. & Hamilton, Andrew
Partner: UNT Libraries Government Documents Department

Thermal Decomposition of Radiation-Damaged Polystyrene

Description: The radiation-damaged polystyrene (given the identification name of 'polycube') was fabricated by mixing high-density polystyrene material ("Dylene Fines # 100") with plutonium and uranium oxides. The polycubes were used in the 1960s for criticality studies during processing of spent nuclear fuel. The polycubes have since been stored for almost 40 years at the Hanford Plutonium Finishing Plant (PFP) after failure of two processes to reclaim the plutonium and uranium oxides from the polystyrene matrix. Thermal decomposition products from this highly cross-linked polystyrene matrix were characterized using Gas Chromatograph/Mass Spectroscopy (GC/MS) system coupled to a horizontal furnace. The decomposition studies were performed in air and helium atmospheres at about 773 K. The volatile and semi-volatile organic products for the radiation-damaged polystyrene were different compared to virgin polystyrene. The differences were in the number of organic species generated and their concentrations. In the inert (i.e., helium) atmosphere, the major volatile organic products identified (in order of decreasing concentrations) were styrene, benzene, toluene, ethylbenzene, xylene, nathphalene, propane, .alpha.-methylbenzene, indene and 1,2,3-trimethylbenzene. But in air, the major volatile organic species identified changed slightly. Concentrations of the organic species in the inert atmosphere were significantly higher than those for the air atmosphere processing. Overall, 38 volatile organic species were identified in the inert atmosphere compared to 49 species in air. Twenty of the 38 species in the inert conditions were also products in the air atmosphere. Twenty-two oxidized organic products were identified during thermal processing in air.
Date: September 26, 2000
Creator: Abrefah, John & Klinger, George S.
Partner: UNT Libraries Government Documents Department

Transition Metal Catalyzed Hydroarylation of Multiple Bonds: Exploration of Second Generation Ruthenium Catalysts and Extension to Copper Systems

Description: Catalysts provide foundational technology for the development of new materials and can enhance the efficiency of routes to known materials. New catalyst technologies offer the possibility of reducing energy and raw material consumption as well as enabling chemical processes with a lower environmental impact. The rising demand and expense of fossil resources has strained national and global economies and has increased the importance of accessing more efficient catalytic processes for the conversion of hydrocarbons to useful products. The goals of the research are to develop and understand single-site homogeneous catalysts for the conversion of readily available hydrocarbons into useful materials. A detailed understanding of these catalytic reactions could lead to the development of catalysts with improved activity, longevity and selectivity. Such transformations could reduce the environmental impact of hydrocarbon functionalization, conserve energy and valuable fossil resources and provide new technologies for the production of liquid fuels. This project is a collaborative effort that incorporates both experimental and computational studies to understand the details of transition metal catalyzed C-H activation and C-C bond forming reactions with olefins. Accomplishments of the current funding period include: (1) We have completed and published studies of C-H activation and catalytic olefin hydroarylation by TpRu{l_brace}P(pyr){sub 3}{r_brace}(NCMe)R (pyr = N-pyrrolyl) complexes. While these systems efficiently initiate stoichiometric benzene C-H activation, catalytic olefin hydroarylation is hindered by inhibition of olefin coordination, which is a result of the steric bulk of the P(pyr){sub 3} ligand. (2) We have extended our studies of catalytic olefin hydroarylation by TpRu(L)(NCMe)Ph systems to L = P(OCH{sub 2}){sub 3}CEt. Thus, we have now completed detailed mechanistic studies of four systems with L = CO, PMe{sub 3}, P(pyr){sub 3} and P(OCH{sub 2}){sub 3}CEt, which has provided a comprehensive understanding of the impact of steric and electronic parameters of 'L' on the catalytic hydroarylation of olefins. ...
Date: February 17, 2011
Creator: Gunnoe, T. Brent
Partner: UNT Libraries Government Documents Department

High temperature structural, polymeric foams from high internal emulsion polymerization

Description: In 1982, a high internal phase emulsion (HIPE) polymerization process to manufacture microcellular, polymeric foam systems was patented by Unilever. This patent discloses a polymerization process that occurs in a water-in-oil emulsion in which the water represents at least 76% of the emulsion by volume. The oil phase consists of vinyl monomers such as styrene and acrylates that are crosslinked by divinyl monomers during polymerization. After polymerization and drying to remove the water phase, the result is a crosslinked polymer foam with an open cell microstructure that is homogeneous throughout in terms of morphology, density, and mechanical properties. Since 1982, numerous patents have examined various HIPE polymerized foam processing techniques and applications that include absorbents for body fluids, cleaning materials, and ion exchange systems. All the published HIPE polymerized foams have concentrated on materials for low temperature applications. Copolymerization of styrene with maleic anhydride and N-substituted maleimides to produce heat resistant thermoplastics has been studied extensively. These investigations have shown that styrene will free radically copolymerize with N-substituted maleimides to create an alternating thermoplastic copolymer with a Tg of approximately 200{degrees}C. However, there are many difficulties in attempting the maleimide styrene copolymerization in a HIPE such as lower polymerization temperatures, maleimide solubility difficulties in both styrene and water, and difficulty obtaining a stable HIPE with a styrene/maleimide oil phase. This work describes the preparation of copolymer foams from N-ethylmaleimide and Bis(3-ethyl-5-methyl-4-maleimide-phenyl)methane with styrene based monomers and crosslinking agents.
Date: February 1996
Creator: Hoisington, M. A.; Duke, J. R. & Apen, P. G.
Partner: UNT Libraries Government Documents Department

Field lysimeter investigations - test results. Low-level waste data base development program: Test results for fiscal years 1986, 1987, 1988, and 1989

Description: The Field Lysimeter Investigations: Low-Level Waste Data Base Development Program, funded by the U.S. Nuclear Regulatory Commission (NRC), is (a) studying the degradation effects in EPICOR-II organic ion-exchange resins caused by radiation, (b) examining the adequacy of test procedures recommended in the Branch Technical Position on Waste Form to meet the requirements of 10 CFR 61 using solidified EPICOR-II resins, (c) obtaining performance information on solidified EPICOR-II ion-exchange resins in a disposal environment, and (d) determining the condition of EPICOR-II liners. Results of the first 4 years of data acquisition from the field testing are presented and discussed. During the continuing field testing, both Portland type I-II cement and Dow vinyl ester-styrene waste forms are being tested in lysimeter arrays located at Argonne National Laboratory-East in Illinois and at Oak Ridge National Laboratory. The experimental equipment is described and results of waste form characterization using tests recommended by the NRC`s {open_quotes}Technical Position on Waste Form{close_quotes} are presented. The study is designed to provide continuous data on nuclide release and movement, as well as environmental conditions, over a 20-year period.
Date: May 1, 1995
Creator: McConnell, J. W., Jr.; Rogers, R. D.; Findlay, M. W.; Davis, E. C.; Jastrow, J. D.; Neilson, R. M., Jr. et al.
Partner: UNT Libraries Government Documents Department