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Millisecond Oxidation of Alkanes

Description: This project was undertaken in response to the Department of Energy's call to research and develop technologies 'that will reduce energy consumption, enhance economic competitiveness, and reduce environmental impacts of the domestic chemical industry.' The current technology at the time for producing 140 billion pounds per year of propylene from naphtha and Liquified Petroleum Gas (LPG) relied on energy- and capital-intensive steam crackers and Fluidized Catalytic Cracking (FCC) units. The propylene is isolated from the product stream in a costly separation step and subsequently converted to acrylic acid and other derivatives in separate production facilities. This project proposed a Short Contact Time Reactor (SCTR)-based catalytic oxydehydrogenation process that could convert propane to propylene and acrylic acid in a cost-effective and energy-efficient fashion. Full implementation of this technology could lead to sizeable energy, economic and environmental benefits for the U. S. chemical industry by providing up to 45 trillion BTUs/year, cost savings of $1.8 billion/year and a combined 35 million pounds/year reduction in environmental pollutants such as COx, NOx, and SOx. Midway through the project term, the program directive changed, which approval from the DOE and its review panel, from direct propane oxidation to acrylic acid at millisecond contact times to a two-step process for making acrylic acid from propane. The first step was the primary focus, namely the conversion of propane to propylene in high yields assisted by the presence of CO2. The product stream from step one was then to be fed directly into a commercially practiced propylene-to-acrylic acid tandem reactor system.
Date: September 30, 2011
Creator: Han, Scott
Partner: UNT Libraries Government Documents Department

FOR STIMUL-RESPONSIVE POLYMERS WITH ENHANCED EFFICIENCY IN RESERVOIR RECOVERY PROCESSES

Description: This report contains a series of terpolymers containing acrylic acid, methacrylamide and a twin-tailed hydrophobic monomer that were synthesized using micellar polymerization methods. These polymer systems were characterized using light scattering, viscometry, and fluorescence methods. Viscosity studies indicate that increasing the nonpolar character of the hydrophobic monomer (longer chain length or twin tailed vs. single tailed) results in enhanced viscosity in aqueous solutions. The interactions of these polymers with surfactants were investigated. These surfactants include sodium dodecyl sulfate (SDS), cetyl trimethyl ammonium bromide (CTAB), Triton X-100. Viscosity measurements of DiC{sub 6}AM and DiC{sub 8}AM mixtures indicate little interaction with SDS, gelation with CTAB, and hemimicelle formation followed by polymer hydrophobe solubilization with Triton X-100. The DiC{sub 10}Am terpolymer shows similar interaction behavior with CTAB and Triton X-100. However, the enhanced hydrophobic nature of the DiC{sub 10} polymer allows complex formation with SDS as confirmed by surface tensiometry. Fluorescence measurements performed on a dansyl labeled DiC{sub 10}Am terpolymer in the presence of increasing amounts of each of the surfactant indicate relative interaction strengths to be CTAB>Triton X-100>SDS. A modified model based on Yamakawa-Fujii and Odjik-Skolnick-Fixman theories was found to describe the contribution of electrostatic forces to the excluded volume of a polyelectrolyte in solution. The model was found to be valid for flexible polymer coils in aqueous salt solutions where intermolecular interactions are minimal. The model suggested that a dimensionless group of parameters termed the dimensionless viscosity should be proportional to the dimensionless ratio of solution screening length to polyion charge spacing. Several sets of experimental data from the literature and from our laboratory have been analyzed according to the model and the results suggest that the two dimensionless groups are indeed related by a universal constant. This model has identified the parameters that are important to fluid mobility, thereby revealing ...
Date: March 26, 2004
Creator: McCormick, Charles & Hester, Roger
Partner: UNT Libraries Government Documents Department

Radioisotope and Radiation Applications. Quarterly Progress Report

Description: An evaluation was given of the possible hazards to consumers from radioisotope residues in consumer products. A laboratory demonstration was given of the use of Mn/sup 54/ to facilitate removal of manganese from process feed water. lt was found in the hazards evaluation that the "worst case" of radiation exposure from residual radioisotopes in steel gives a radiation exposure somewhat less than the maximum allowable dose levels for occupational exposure. Initial study indicates that for actual cases, the radiation exposures to be expected from radioisotope residues in steel products would ordinarily be small compared to natural background. An exception to this generalization might be found when a longer lived isotope like Mn/sup 54/ was present. Preliminary results of the laboratory demonstnation of using Mn/sup 54/ to monitor the removal of manganese from feed water indicated that the method may allow a considerable improvement in accuracy of process control. The study of the mechanism of formation of free radicals in polymeric materials was continued. Emphasis was placed on examination of the effect of structural factors on the efficiency of free-radical site formation in acrylate polymers. The investigation was extended to include an examination of the effect on free-radical formation of the constituents on the carbon atom located alpha to the ester group. Polymethylacrylate, polymethylmethacrylate, and polymethyl- alpha -chloroacrylate were used in this study. Measurement of the volatile products from the irradiation of the polymethyl- alpha -chloroacrylate was completed. The data substantiated earlier findings which indicated that the point of attack in free-radical formation occurs on the ester side chain. (auth)
Date: January 18, 1961
Creator: Sunderman, D. N.
Partner: UNT Libraries Government Documents Department

Responsive copolymers for enhanced petroleum recovery. Quarterly technical progress report, December 21, 1994--March 22, 1995

Description: The purpose of this study is to extend the concept of micellar polymerization to more complex systems, and to explore the responsive nature of hydrophobically modified polyelectrolytes by tailoring the microstructure. The synthesis of hydrophobically modified acrylamide/acrylic acid copolymer is described. These types of polymers are of interest as thickening agents utilized in enhanced oil recovery.
Date: May 1, 1995
Creator: McCormick, C. & Hester, R.
Partner: UNT Libraries Government Documents Department

RADIOISOTOPE AND RADIATION APPLICATIONS. Quarterly Progress Report

Description: The study of the formation mechanism of free radicals in polymeric materials was continued. Emphasis was placed on an examination of the effect of structural factors on the efficiency of free-radical site formation in acrylate polymers. Site measurements as a function of dose were made for polymethacrylamide and repeated for polymethacrylic acid. The volatile products from the irradiation of polyacrylic acid. polymethacrylic acid, poly-ter- butylmethacrylate. and polycyclohexyl methacrylate were measured quantitatively by mass spectrometry and vapor-phase chromatography. Grafting studies were initiated using polymethylmethacrylate as base polymer and vinylpyrrolidone as graft monomer. (auth)
Date: July 18, 1961
Creator: Sunderman, D.N. ed.
Partner: UNT Libraries Government Documents Department

RADIOISOTOPE AND RADIATION APPLICATIONS. Quarterly Progress Report

Description: Exploratory and optimization experiments in the use of in-process isotope neutron sources to produce short-lived intrinsic radiotracers were initiated. Flux determinations using manganese sulfate solutions and indium foils were performed. The maxtmum thermal-neutron flux measured by indium acttvation was found to be 9.6 x 10/sup 4/ n/(cmsup 2/) (sec) for a 10-curie polonium-beryllium source. The peak flux occurred 3.2 cm from the center of the source through approximately 1.6 cm of water moderator. The study of the mechanism of formation of free radicals in polymeric materials was continued. Again, emphasis was placed on an examination of the effects of structure and molecular weight on the efficiency of free-radical formation in acrylate and methacrylate polymers. In addition, the investtgation of tbe potential application of this information to thc development of graft copolymers was continued. (auth)
Date: January 18, 1962
Creator: Sunderman, D.N. ed.
Partner: UNT Libraries Government Documents Department

THE EFFECT OF RADIATION ON THE MECHANICAL PROPERTIES OF POLYMERS. A BIBLIOGRAPHY OF THE UNCLASSIFIED LITERATURE, 1955-SEPTEMBER 1962

Description: A bibliography of approximates 440 references is presented which is arranged into sections dealing with polyacrylates, polyamides, polybutadienes and copolymers, polycarbonates, cellulosics, epoxy resins, polyesters, polyethers, polyethylenes, natural rubber, neoprene, phenolics, polypropylene, rubbers, silicones, polystyrenes, urethanes, polyvinylidenes, polyvinyls, and miscellaneous systems. Reviews, data compilations, books, and references dealing with dynamic mechanical properties are also listed. (D.L.C.)
Date: July 1, 1963
Partner: UNT Libraries Government Documents Department

RADIOISOTOPE AND RADIATION APPLICATIONS. Quarterly Progress Report

Description: Results of the final dynamic experiments with the ironremoval process model using Fe/sup 59/ indicated that the intrinsic-radiotracer method is rapid, accurate, and suitable for continuous readout. Results from both static and dynamic experiments on the use of Mn/sup 54/ to aid in removing manganese from process water indicated that intrinsic radiotracers can be used to help remove low-concentration critical impurities. One phase of the hazards evaluation was concerned with the ingestion of radiotracer residues which might arise from corrosion of radiotracer-containing steel products. It was concluded that no hazard exists from this source. Another part of the hazards study was concerned with the technical hazards to sensitive industries which might use steel containing radiotracer residues. This area is the most sensitive one encountered in the study. The study of the mechanism of formation of free radicals in polymeric materials was continued. Emphasis was placed on examination of the effect of structural factors on the efficiency of free-radical site formation, especially in acrylate polymers. An initial investigation of the effect of polymer tacticity was completed using polypropylene. The influence of molecular mobility on site formation in polymethylacrylate was established. Measurements of the volatile products from irradiation of the polymers was completed. The concentration of free-radical sites determined for each of these polymers from the volatile-product data agreed reasonably well with that found by means of electron paramagnetic resonance. Preliminary studies were initiated to develop safety performance criteria for sealed sources and to determine the applicability of standard test procedures employed in other industries. (auth)
Date: May 2, 1961
Creator: Sunderman, D.N., ed.
Partner: UNT Libraries Government Documents Department

Diosmacycloalkanes as models for the formation of hydrocarbons from surface methylenes. Progress report, November 1, 1991--October 31, 1992

Description: We are making progress on our investigation of the mechanism of olefin exchange with Os{sub 2}(C{sub 2}H{sub 4})(CO){sub 8}. We are probing this system by kinetic study of the reaction of Os{sub 2}(C{sub 2}H{sub 4})(CO){sub 8} with butyl acrylate (BA) under various pressures of ethylene.
Date: May 1, 1992
Creator: Norton, J. R.
Partner: UNT Libraries Government Documents Department

RADIOISOTOPE AND RADIATION APPLICATIONS QUARTERLY PROGRESS REPORT. SECTION I. USE OF INTRINSIC RADIOACTIVE TRACERS FOR PROCESS CONTROL. SECTION II. RADIATION-INDUCED GRAFT-POLYMERIZATION STUDIES

Description: Research was continued in the areas of intrinsic radioactive tracers for industrial process control and the influence of structural factors in radiation- induced graft polymerization. The use of in-process isotope neutron soarces to produce short-lived radiotraces is discussed. A 10c Po--Be neutron source was obtained for exploratory experiments. The design and construction of a neutronsource storage shield and an activatioa-cell holder are underway. The effect of structural factors oii the eIficiency of free-radical site formation in acrylate and methacrylate polymers was emphasized. Site measurements versus dose were made for poly-n-hexylmethacrylate. Two additional methods for measuring free-radical conceiitrations, a chemical method employing diphenylpicrylhydrazyl and hydroquinone and a method based on molecular-weight decreases, were developed. The grafting studies were continued. (M.C.G.)
Date: October 23, 1961
Creator: McFarling, J.L.; Gluck, P.; Kircher, J.F.; Sunderman, D.N.; Sliemers, F.A.; Luttinger, M. et al.
Partner: UNT Libraries Government Documents Department

Diosmacycloalkanes as models for the formation of hydrocarbons from surface methylenes

Description: We are making progress on our investigation of the mechanism of olefin exchange with Os{sub 2}(C{sub 2}H{sub 4})(CO){sub 8}. We are probing this system by kinetic study of the reaction of Os{sub 2}(C{sub 2}H{sub 4})(CO){sub 8} with butyl acrylate (BA) under various pressures of ethylene.
Date: May 1, 1992
Creator: Norton, J.R.
Partner: UNT Libraries Government Documents Department

Fever--A One-Dimensional Few-Group Depletion Program for Reactor Analysis

Description: The one-dimensional difiusion-theory depletion program FEVER, written in FORTRAN-II for a 32,000-word computer is described. The code allows for the representation of self-shielded burnable poisons and provides methods for automatically adjusting control poisons in various regions of the reactor according to some specified sequence. No intermediate tape manipulation is required during the calculations, since all program and data storage are contained in the fast memory of the computer. Information oriented to meet the needs of the potential user of the program and a documentation of the programming details. are presented. (auth)
Date: November 28, 1962
Creator: Todt, F.
Partner: UNT Libraries Government Documents Department

Degradation of cellulosic biomass and its subsequent utilization for the production of chemical feedstocks. Progress report, December 1, 1976--February 28, 1977

Description: The microbial degradation of cellulosic biomass has focused on the use of a thermophilic (55 to 60/sup 0/C), anaerobic microorganism, Clostridium thermocellum. When this organism is grown with a crystalline cellulose, the cellulases produced are mainly extracellular. This same organism when grown on solka floc, high specific growth rates are exhibited as well as the ability to produce high concentrations of soluble reducing sugars. The rate of soluble sugar production appears to be growth associated. Studies on acrylic acid production are focused on two organisms: Peptostreptococcus elsdenii and Clostridium propionicum. An economic analysis on the acetone/butanol fermentation has been completed. The results show that continuous operation can reduce significantly the production cost compared to batch operation with the cost of raw material being major fractions for both processes. An increase in solvent concentration will effect substantial cost reduction. The production of acetic acid by Clostridium thermoaceticum has been shown to occur rapidly by this organism. Acetic acid concentration between 15 to 20 gm/liter have been achieved, corresponding to 86 percent of the theoretical maximum yield.
Date: May 1, 1977
Creator: Wang, D. I. C.; Cooney, C. L.; Demain, A. L.; Gomez, R. F. & Sinskey, A. J.
Partner: UNT Libraries Government Documents Department

Novel Bioplastics and biocomposites from Vegetable Oils

Description: Polymeric materials have been prevalent in our everyday lives for quite a long time. Most of today's polymeric materials are derived from nonrenewable petroleum-based feedstocks. Instabilities in the regions where petroleum is drilled, along with an increased demand in petroleum, have driven the price of crude oil to record high prices. This, in effect, increases the price of petroleum-based polymeric materials, which has caused a heightened awareness of renewable alternatives for polymeric feedstocks. Cellulose, starch, proteins and natural oils have all been examined as possible polymeric feedstocks. Natural oils are commercially available on a large scale and are relatively cheap. It is projected that the U.S. alone will produce 21 billion pounds of soybean oil in the period 2008/2009. Natural oils also have the advantages of inherent biodegradability, low toxicity, high purity and ready availability. Most natural oils possess a triglyceride structure as shown in Figure 1. Most natural oils have a unique distribution of fatty acid side chains, along with varying degrees of unsaturation per triglyceride. Common fatty acid side chains in naturally occurring oils are palmitic acid (C16:0), a 16 carbon fatty acid with no unsaturation; stearic acid (C18:0), an 18 carbon fatty acid with no unsaturation; oleic acid (C18:1), an 18 carbon fatty acid with one double bond; linoleic acid (C18:2), an 18 carbon fatty acid with two double bonds; and linolenic acid (C18:3), an 18 carbon fatty acid with three double bonds. Of course, there are other fatty acids with varying degrees of unsaturation, but their abundance is usually minimal. All of the unsaturated fatty acids mentioned have naturally occurring cis double bonds, which is common for most unsaturated fatty acids. In addition, the afore mentioned fatty acids have the first double bond at the position of carbon 9 (C9), followed by carbon 12 (C12), if ...
Date: August 18, 2008
Creator: Henna, Phillip H.
Partner: UNT Libraries Government Documents Department

Infrared and near infrared transient absorption spectroscopy of molecular free radicals

Description: The advantages of absorption spectroscopy at low absorbances include a linear relationship between signal size and number of absorbing molecules, line of sight measurement, and easily interpretable lineshape functions. The main disadvantage is due to the necessity of measuring a small change in light intensity, usually in the presence of a strong background, which limits the sensitivity. In this work, recent results obtained using absorption techniques with continuous wave lasers to measure vibrational and electronic spectra in the mid- and near-infrared of small free radicals are reported. The radical of interest was generated by excimer laser photolysis of a chemically stable precursor molecule and detected by measuring the transient decrease in power of a continuous wave probe laser that traversed the photolyzed volume before being imaged onto a detector.
Date: December 31, 1993
Creator: Sears, T. J.; Wu, M.; Hall, G. E.; Chang, B. C.; Hansford, G.; Bloch, J. C. et al.
Partner: UNT Libraries Government Documents Department

Degradation of cellulosic biomass and its subsequent utilization for the production of chemical feedstocks. Progress report, March 1, 1977--May 31, 1977

Description: The degradation of cellulosic biomass continues to focus on the anaerobic thermophile Clostridium thermocellum. When grown on crystalline cellulose (MN300) in batch culture, there is an initial rapid accumulation of reducing sugars but the sugars are rapidly metabolized in later times during the fermentation. When grown on Solka floc with periodic addition of the substrate, there is a continual accumulation of reducing sugars (xylose, glucose, and cellobiose) as well as ethanol and acetic acid during the entire course of the fermentation. In the presence of surfactant in the growth medium, there is an increased appearance of extracellular cellulases. A chemically defined medium is being developed for growth Cl. thermocellum in order to study the enzyme regulations. Lastly, a trinitrophenyl-carboxylmethyl cellulose substrate for determining cellulose activity appears to be a promising and rapid assay. Progress in the genetic manipulations has been cautious but promising. Preliminary evidence leads to optimistic projection on the presence of plasmids and bacteriophage in Cl. thermocellum. The production of chemical feedstocks continues to focus on acrylic acid, acetone/butanol and acetic acid. Studies with cell free extracts of Clostridium propionicum have shown the production and accumulation of acrylic acid from lactic acid. The use of electron acceptor in cell-free systems has shown effective prevention on the reduction of acrylic acid to propionic acid. Medium development and strain selection using available acetone/butanol producing Cl. acetobutylicum have been initiated. There is every indication that these strains are capable to produce mixed solvents close to the theoretical maximum yield. An accurate and rapid method for quantifying acetic acid was developed. This technique is being used to examine the pertinent parameters on the production of acetic acid by Clostridium thermoaceticum.
Date: June 1, 1977
Creator: Wang, D.I.C.; Cooney, C.L.; Demain, A.L.; Gomez, R.F. & Sinskey, A.J.
Partner: UNT Libraries Government Documents Department

Performance testing of the Acurex solar-collector Model 3001-03

Description: Results are summarized of tests conducted at the Collector Module Test Facility on an Acurex Model 3001-03 Parabolic Trough Concentrating Solar Collector. Test temperaure range was 100/sup 0/C to 300/sup 0/C. Tests were conducted with the collector axis oriented east-west and again with the collector axis oriented north-south. Three collectors were tested: one using polished aluminum mirrors, one using glass mirrors, and another using an aluminized acrylic film mirror.
Date: March 1, 1982
Creator: Dudley, V.E. & Workhoven, R.M.
Partner: UNT Libraries Government Documents Department

Degradation of cellulosic biomass and its subsequent utilization for the production of chemical feedstocks. Progress report, June 1-August 31, 1978

Description: Studies concerning the cellobiose properties of Clostridium thermocellum were started to determine if the cellulose degradation end products can be enhanced for glucose (with a subsequent decrease in cellobiose). Implications of preliminary studies indicate that the cells or the enzyme(s) responsible for converting cellobiose to glucose can be manipulated environmentally and genetically to increase the final yield of glucose. The second area of effort is to the production of chemical feedstocks. Three fermentations have been identified for exploration. Preliminary reports on acrylic acid acetone/butanol, and acetic acid production by C. propionicum, C. acetobutylicum, and C. thermoaceticum, respectively, are included. (DMC)
Date: August 1, 1978
Creator: Wang, D.I.C.; Cooney, C.L.; Demain, A.L.; Gomez, R.F. & Sinskey, A.J.
Partner: UNT Libraries Government Documents Department