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The Mercury-Sensitized Photo-Reactions of 2,3-Dimethyl Butane

Description: The work encompassed by this thesis is partially a reproduction of the results obtained by John A. Marcia in his work on the photo-chemical reactions of branched hydrocarbons. The previous work done on this particular problem was rendered partially valueless because of the loss of the liquid hydrocarbon product when a fractionation column at the Texas Company Laboratory, Beacon, New York, broke during the fractionation run.
Date: 1947
Creator: Sutton, Cecil C.
Partner: UNT Libraries

In situ laser raman spectroscopy during sequential oxidizing and reducing conditions for a vanadium-phosphorous-oxide catalyst

Description: A VPO catalyst prepared in an organic medium has been studied by in situ laser Raman spectroscopy under reaction conditions for n-butane oxidation to maleic anhydride. Data were obtainable at low laser power and short collection times. Raman characterization during continuous flow (steady state) revealed that the (VO){sub 2}P{sub 2}O{sub 7} phase was present. Sequential oxidizing (10% O{sub 2} in N{sub 2}) and reducing (2% n-butane in N{sub 2}) conditions were explored at 350{degree} and 400{degree}C. Cycling (unsteady state) revealed enhancement of {alpha}{sub II}-VOPO{sub 4}, {beta}-VOPO{sub 4}, {gamma}-VOPO{sub 4}, and {delta}-VOPO{sub 4} during oxidizing conditions; intensity of Raman bands due to (VO){sub 2}P{sub 2}O{sub 7} increased during reducing conditions.
Date: December 31, 1995
Creator: Soejarto, A.D.; Schrader, G.L. & Coulston, G.W.
Partner: UNT Libraries Government Documents Department


Description: A hydrogen rich, low density liquid, contained within the internal volume of a cylindrical liner, was requested of the Polymers and Coatings Group (MST-7) of the Los Alamos Materials Science Division for one of the last liner driven experiments conducted on the Los Alamos Pegasus facility. The experiment was a continuation of the Raleigh-Taylor hydrodynamics series of experiments and associated liners that have been described previously [1,2].
Date: June 1, 2001
Partner: UNT Libraries Government Documents Department

Carburetion of Combustible Gas with Butane and Propane-Butane Mixtures with Particular Reference to the Carburetion of Water Gas

Description: Report issued by the Bureau of Mines over the carburetion of many different fuels. The report pays particular attention to the carburetion of water gas. Carburetion methods and results are presented and discussed. This report includes tables, and illustrations.
Date: 1929
Creator: Odell, William Wallace
Partner: UNT Libraries Government Documents Department

Saline Water Conversion by Direct Freezing With Butane

Description: Report presenting a study of a plant to produce 10,000,000 gallons per day of fresh water from sea water. The process used is direct freezing brought about by the evaporation of a hydrocarbon refrigerant in contact with sea water, washing the ice free of saline liquor, and melting the ice to potable water by the condensation of butane vapor.
Date: 1960
Creator: Karnofsky, George & Steinhoff, Paul F.
Partner: UNT Libraries Government Documents Department

In situ vibrational spectroscopic investigation of C{sub 4} hydrocarbon selective oxidation over vanadium-phosphorus-oxide catalysts

Description: n-Butane selective oxidation over the VPO catalyst to maleic anhydride is the first and only commercialized process of light alkane selective oxidation. The mechanism of this reaction is still not well known despite over twenty years of extensive studies, which can partially be attributed to the extreme difficulties to characterize catalytic reactions real-time under typical reaction conditions. In situ spectroscopic characterization techniques such as Infrared spectroscopy and laser Raman spectroscopy were used in the current mechanistic investigations of n-butane oxidation over VPO catalysts. To identify the reaction intermediates, oxidation of n-butane, 1,3-butadiene and related oxygenates on the VPO catalyst were monitored using FTIR spectroscopy under transient conditions. n-Butane was found to adsorb on the VPO catalyst to form olefinic species, which were further oxidized to unsaturated, noncyclic carbonyl species. The open chain dicarbonyl species then experienced cycloaddition to form maleic anhydride. VPO catalyst phase transformations were investigated using in situ laser Raman spectroscopy. This report contains Chapter 1: General introduction; Chapter 2: Literature review; and Chapter 5: Conclusion and recommendations.
Date: May 10, 1999
Creator: Xue, Z.Y.
Partner: UNT Libraries Government Documents Department

Hydrophobic Dewatering of Fine Coal. Topical report, March 1, 1995-March 31, 1997

Description: Many advanced fine coal cleaning technologies have been developed in recent years under the auspices of the U.S. Department of Energy. However, they are not as widely deployed in industry as originally anticipated. An important reason for this problem is that the cleaned coal product is difficult to dewater because of the large surface area associated with fine particles. Typically, mechanical dewatering, such as vacuum filtration and centrifugation, can reduce the moisture to 20-35% level, while thermal drying is costly. To address this important industrial problem, Virginia Tech has developed a novel dewatering process, in which water is displaced from the surface of fine particulate materials by liquid butane. Since the process is driven by the hydrophobic interaction between coal and liquid butane, it was referred to as hydrophobic dewatering (HD). A fine coal sample with 21.4 pm median size was subjected to a series of bench-scale HD tests. It was a mid-vol bituminous coal obtained from the Microcel flotation columns operating at the Middle Fork coal preparation plant, Virginia. All of the test results showed that the HD process can reduce the moisture to substantially less than 10%. The process is sensitive to the amount of liquid butane used in the process relative to the solids concentration in the feed stream. Neither the intensity nor the time of agitation is critical for the process. Also, the process does not require long time for phase separation. Under optimal operating conditions, the moisture of the fine coal can be reduced to 1% by weight of coal.
Date: December 31, 1997
Creator: Yoon, R.; Sohn, S.; Luttrell, J. & Phillips, D.
Partner: UNT Libraries Government Documents Department

Nanorheology of Liquid Alkanes

Description: We report molecular dynamics simulations of liquid alkanes, squalane and tetracosane, confined between moving walls to which butane chains are tethered, effectively screening the details of the wall. As in an experiment, heat is removed by thermostatting the tethered molecules. Results obtained at high strain rates, typical of practical applications, suggest little or no difference between the bulk rheology and confined flow, and the occurrence of a high degree of slip at the wall-fluid interface at the conditions studied. At relatively low velocities and high densities, tetracosane shows the formation of fully-extended chains at certain wall spacings.
Date: September 1, 1997
Creator: Gupta, S.A., Cochran, H.D., Cummings, P.T.
Partner: UNT Libraries Government Documents Department

Fueling Requirements for Steady State high butane current fraction discharges

Description: The CT injector originally used for injecting CTs into 1T toroidal field discharges in the TdeV tokamak was shipped PPPL from the Affiliated Customs Brokers storage facility in Montreal during November 2002. All components were transported safely, without damage, and are currently in storage at PPPL, waiting for further funding in order to begin advanced fueling experiments on NSTX. The components are currently insured through the University of Washington. Several technical presentations were made to investigate the feasibility of the CT injector installation on NSTX. These technical presentations, attached to this document, were: (1) Motivation for Compact Toroida Injection in NSTX; (2) Assessment of the Engineering Feasibility of Installing CTF-II on NSTX; (3) Assessment of the Cost for CT Installation on NSTX--A Peer Review; and (4) CT Fueling for NSTX FY 04-08 steady-state operation needs.
Date: October 8, 2003
Creator: R.Raman
Partner: UNT Libraries Government Documents Department

Liquid butane filled load for a liner driven Pegasus experiment.

Description: A hydrogen rich, low density liquid, contained within the internal volume of a cylindrical liner, was requested of the Polymers and Coatings Group (MST-7) of the Los Alamos Materials Science Division for one of the last liner driven experiments conducted on the Los Alamos Pegasus facility. The experiment (Fig.1) was a continuation of the Raleigh-Taylor hydrodynamics series of experiments and associated liners that have been described previously.
Date: January 1, 2001
Creator: Salazar, M. A. (Mike A.); Armijo, E. V. (Elfino V.); Anderson, W. E. (Wallace E.); Atchison, W. L. (Walter L.); Bartos, J. J. (Jacob J.); Garcia, F. (Fermin) et al.
Partner: UNT Libraries Government Documents Department

Supercritical catalysts of light hydrocarbon conversion. DOE PETC eighth quartery report, July 1, 1995--September 30, 1995

Description: The solid superacid catalysts investigated in this project catalyze hydrocarbon conversions by routes involving carbocation intermediates. This report is a summary of mechanisms of hydrocarbon conversion catalyzed by these and related solid acids. This mechanistic information summarized here is important to the present project because it provides guidance for the modeling of the kinetics of the catalytic butane conversion and propane conversion. Because of the difficulty of determining surface reaction intermediates, understanding of surface reaction mechanisms lags far behind that of solution reaction mechanisms, and what is known about the former is fragmentary and often largely based on presumed analogies with the latter, combined with results such as those from tracer experiments, kinetics experiments, and theoretical chemistry.
Date: June 1, 1996
Creator: Gates, B.C.
Partner: UNT Libraries Government Documents Department

Engineering development of advanced physical fine coal cleaning for premium fuel applications: Subtask 3.3 - dewatering studies

Description: If successful, the novel Hydrophobic Dewatering (HD) process being developed in this project will be capable of efficiently removing moisture from fine coal without the expense and other related drawbacks associated with mechanical dewatering or thermal drying. In the HD process, a hydrophobic substance is added to a coal-water slurry to displace water from the surface of coal, while the spent hydrophobic substance is recovered for recycling. For this process to have commercialization potential, the amount of butane lost during the process must be small. Earlier testing revealed the ability of the hydrophobic dewatering process to reduce the moisture content of fine coal to a very low amount as well as the determination of potential butane losses by the adsorption of butane onto the coal surface. Work performed in this quarter showed that the state of oxidation affects the amount of butane adsorbed onto the surface of the coal and also affects the final moisture content. the remaining work will involve a preliminary flowsheet of a continuous bench-scale unit and a review of the economics of the system. 1 tab.
Date: October 1, 1996
Creator: Yoon, R.H., Phillips, D.I., Sohn, S.M., Luttrell, G.H.
Partner: UNT Libraries Government Documents Department

Dynamics of Exchange at Gas-Zeolite Interfaces 1: Pure Component n-Butane and Isobutane

Description: The authors present the results of molecular dynamics simulations of n-butane and isobutane in silicalite. They begin with a comparison of the bulk adsorption and diffusion properties for two different parameterizations of the interaction potential between the hydrocarbon species, both of which have been shown to reproduce experimental gas-liquid coexistence curves. They examine diffusion as a function of the loading of the zeolite, as well as the temperature dependence of the diffusion constant at loading and for infinite dilution. They continue with simulations in which interfaces are formed between single component gases and the zeolite. After reaching equilibrium, they examine the dynamics of exchange between the bulk gas and the zeolite. Finally, they calculate the permeability of the zeolite for n-butane and isobutane as a function of pressure. Their simulations are performed for a number of different gas temperatures and pressures, covering a wide range of state points.
Date: July 13, 2000
Partner: UNT Libraries Government Documents Department

Condensation analysis for plate-frame heat exchangers

Description: A theoretical analysis is presented to predict single component and binary-mixture condensation in plate-frame heat exchangers. A thermodynamic property model based on the Peng-Robinson equation of state was developed for the binary-mixture equilibrium and formulated into a performance prediction program. A set of equations was formulated and a calculation algorithm was developed to predict the local rate of heat and mass transfer for binary mixtures. Friction-factor and heat-transfer-coefficient correlations were developed using experimental data obtained with ammonia condensation. The role of the mass-transfer resistance associated with the condensation process were analyzed for a propane/butane mixture using two limiting cases: (1) no liquid-phase mass-transfer resistance, and (2) infinite liquid-phase mass-transfer resistance. The results show that the vapor-phase mass-transfer resistance is the controlling mechanism for binary-mixture condensation.
Date: July 1, 1995
Creator: Arman, B. & Rabas, T.J.
Partner: UNT Libraries Government Documents Department

Pentan isomers compound flame front structure

Description: The fuels (hexane, pentane, diethyl ether) and conditions investigated in this study are relevant to engine knock in spark- ignition engines. A review is provided of the field of low temperature hydrocarbon oxidation. Studies were made of radical and stable intermediate distribution in the front of cool flames: Maximum concentrations of H atoms and peroxy radicals were observed in the luminous zone of the cool flame front. Peroxy radicals appear before the luminous zone at 430 K due to diffusion. H atoms were found in cool flames of butane and hexane. H atoms diffuses from the luminous zone to the side of the fresh mixture, and they penetrate into the fresh mixture to a small depth. Extension of action sphear of peroxy radicals in the fresh mixture is much greater than that of H atoms due to their small activity and high concentrations.
Date: August 13, 1995
Creator: Mansurov, Z. A.; Mironenko, A. W.; Bodikov, D. U. & Rachmetkaliev, K. N.
Partner: UNT Libraries Government Documents Department

Low Cost Chemical Feedstocks Using an Improved and Energy Efficient Natural Gas Liquid (NGL) Removal Process, Final Technical Report

Description: The overall objective of this project is to develop a new low-cost and energy efficient Natural Gas Liquid (NGL) recovery process - through a combination of theoretical, bench-scale and pilot-scale testing - so that it could be offered to the natural gas industry for commercialization. The new process, known as the IROA process, is based on U.S. patent No. 6,553,784, which if commercialized, has the potential of achieving substantial energy savings compared to currently used cryogenic technology. When successfully developed, this technology will benefit the petrochemical industry, which uses NGL as feedstocks, and will also benefit other chemical industries that utilize gas-liquid separation and distillation under similar operating conditions. Specific goals and objectives of the overall program include: (i) collecting relevant physical property and Vapor Liquid Equilibrium (VLE) data for the design and evaluation of the new technology, (ii) solving critical R&D issues including the identification of suitable dehydration and NGL absorbing solvents, inhibiting corrosion, and specifying proper packing structure and materials, (iii) designing, construction and operation of bench and pilot-scale units to verify design performance, (iv) computer simulation of the process using commercial software simulation platforms such as Aspen-Plus and HYSYS, and (v) preparation of a commercialization plan and identification of industrial partners that are interested in utilizing the new technology. NGL is a collective term for C2+ hydrocarbons present in the natural gas. Historically, the commercial value of the separated NGL components has been greater than the thermal value of these liquids in the gas. The revenue derived from extracting NGLs is crucial to ensuring the overall profitability of the domestic natural gas production industry and therefore of ensuring a secure and reliable supply in the 48 contiguous states. However, rising natural gas prices have dramatically reduced the economic incentive to extract NGLs from domestically produced natural gas. ...
Date: August 10, 2012
Creator: Meyer, Howard, S. & Lu, Yingzhong
Partner: UNT Libraries Government Documents Department

Correlation between shape resonance energies and C-C bond length in carbon-containing molecules: Elastic electron scattering and carbon K-shell excitation by photons

Description: We document the correlation of shape resonance energies resulting from (i) elastic electron scattering and (ii) carbon K-shell excitation with ic bond order (C-C bond length) for C{sub 2}H{sub 2}, C{sub 2}H{sub 4}, C{sub 2}H{sub 6}, C{sub 3}H{sub 8}, C{sub 4}H{sub 10}, and C{sub 6}H{sub 6}. A relationship between K-shell {sigma} resonances and bond length was experimentally pointed out previously. These correlations are qualitatively interpreted to indicate that as molecular size increases (or as bond length increases), the configuration space available for valence electrons increases, reducing energy levels rather uniformly and mowing these correlations to emerge. The similarity of shape resonances in electron scattering and photoexcitation occurs because major events in the resonances take place slightly outside the molecular field and receive little influence from the inner structure of the molecule.
Date: June 1, 1994
Creator: Kimura, Mineo
Partner: UNT Libraries Government Documents Department

Fischer-tropsch synthesis in supercritical fluids. Quarterly technical progress report, April 1, 1993--June 30, 1993

Description: We have completed modifications of the Taylor Dispersion Apparatus so that propane can be used as a solvent. Problems were encountered initially compressing propane to the necessary pressures because of cavitation in the liquid pump. This problem was overcome by placing a check valve in the line after the pump and pressures of 2500 psi have been achieved. The system has been pressure tested by using a soap solution on exposed joints and performing a mass balance (leak test). The mass balance was made by reading the volumetric flow rate of liquid in the syringe pump and converting this to expected gas flow rate. The liquid was then vaporized and a dry gas meter measured the amount of gas at the exit of the apparatus. The expected and measured gas flow rates were in excellent agreement, indicating that there are no significant leaks in the system. Presently, we are having problems with the use of UV detection for the dim using compounds. The detector is successfully auto-zeroing with a blank cell and with Co{sub 2}. With the use of instrument grade propane, however, the detector is unable to auto-zero because of absorption of unknown impurity. We believe this problem is caused by a sulfur compound in the propane gas cylinder and we plan to install an active carbon guard bed to remove a sulfur containing compounds.
Date: July 29, 1993
Creator: Akgerman, A. & Bukur, D. B.
Partner: UNT Libraries Government Documents Department

Superacid catalysis of light hydrocarbon conversion. Final report, August 26, 1993--August 26, 1996

Description: Motivated by the goal of finding improved catalysts for low- temperature conversion of light alkanes into fuel components or precursors of fuel components, the researchers have investigated sulfated zirconia and promoted sulfated zirconia for conversion of butane, propane, and ethane. Catalyst performance data for sulfated zirconia promoted with iron and manganese show that it is the most active noncorrosive, nonhalide catalyst known for n-butane isomerization, and it is an excellent candidate catalyst for new low- temperature n-butane isomerization processes to make isobutane, which can be converted by established technology into methyl t-butyl ether (MTBE). Various transition metals have been found to work as promoters of sulfated zirconia for n-butane isomerization. The combination of iron and manganese is the best known combination of promoters yet discovered. The iron- and manganese-promoted sulfated zirconia is also a catalyst for conversion of propane and of ethane. Ethane is converted into ethylene and butanes in the presence of the iron- and manganese-promoted sulfated zirconia; propane is also converted into butane, among other products. However, the activities of the catalyst for these reactions are orders of magnitude less than the activity for n-butane conversion, and there is no evidence that the catalyst would be of practical value for conversion of alkanes lighter than butane. The product distribution data for ethane and propane conversion provide new insights into the nature of the catalyst and its acidity. These data suggest the involvement of Olah superacid chemistry, whereby the catalyst protonates the alkane itself, giving carbonium ions (as transition states). The mechanism of protonation of the alkane may also pertain to the conversion of butane, but there is good evidence that the butane conversion also proceeds via alkene intermediates by conventional mechanisms of carbenium ion formation and rearrangement.
Date: December 31, 1996
Creator: Gates, B.C.
Partner: UNT Libraries Government Documents Department

Superacid catalysis of light hydrocarbon conversion. DOE PETC seventh quarterly progress report, April 1, 1995--July 31, 1995

Description: Iron- and manganese-promoted sulfated zirconia is a catalyst for the conversion of propane, but the rate of conversion of propane is much less than the rate of conversion of butane. Whereas this catalyst appears to be a good candidate for practical, industrial conversion of butane, it appears to lack sufficient activity for practical conversion of propane. The propane conversion data reported here provide excellent insights into the chemistry of the catalytic conversion. Solid and catalysts, namely, sulfated zirconia, iron- and manganese-promoted sulfated zirconia, and USY zeolite, were tested for conversion of propane at 1 atm, 200-450{degrees}C, and propane partial pressures in the range of 0.01-0.05 atm. Both promoted and unpromoted sulfated zirconia were found to be active for conversion of propane into butanes, pentanes, methane, ethane, ethylene, and propylene in the temperature range of 200-350{degrees}C, but catalyst deactivation was rapid. At the higher temperatures, only cracking and dehydrogenation products were observed. In contrast to the zirconia-supported catalysts, USY zeolite was observed to convert propane (into propylene, methane, and ethylene) only at temperatures {ge}400{degrees}C. The initial (5 min on stream) rates of propane conversion in the presence of iron- and manganese-promoted sulfated zirconia, sulfated zirconia, and USY zeolite at 450{degrees}C and 0.01 atm propane partial pressure were 3.3 x 10{sup -8}, 0.3 x 10{sup -8}, and 0.06 x 10{sup -8} mol/(s{center_dot}g), respectively. The product distributions in the temperature range 200-450{degrees}C are those of acid-base catalysis, being similar to what has been observed in superacid solution chemistry at temperatures <0{degrees}C. If propane conversion at 450{degrees}C can be considered as a probe of acid strength of the catalyst, the activity comparison suggests that the promoted sulfated zirconia is a stronger acid than sulfated zirconia, which is a stronger acid than USY zeolite.
Date: February 1, 1996
Creator: Gates, B.C.
Partner: UNT Libraries Government Documents Department

Superacid catalysis of light hydrocarbon conversion. Eleventh quarterly report, April 1, 1996--June 30, 1996

Description: The new catalyst Fe- and Mn-promoted sulfated zirconia is remarkably active for the low-temperature (even room temperature) isomerization of n-butane to give isobutane in the near absence of side products. Thus this catalyst offers excellent potential for practical application in this process. The catalyst is so active that it even converts smaller alkanes, including propane and ethane. The ethane conversion is orders of magnitude slower than the butane conversion, and the prospects for practical application with ethane are apparently negligible. However, the results for ethane conversion provide strong evidence that the alkane conversions proceed (at least under some conditions) by protonation of the alkane with the catalyst; thus the catalyst is comparable to superacids, and the chemistry is analogous to that occurring in superacid solutions. This insight will be useful in further improvement of the catalyst and the potential process for butane isomerization. The catalyst is active for alkane cracking at temperatures of typically 200-300{degrees}C, and evidence, summarized here, indicates that numerous reactions of alkanes begin as the catalyst protonates the alkane reactant. The kinetics data for this family of reactions fall on a linear compensation effect plot; such data for reactions that do not proceed via such a mechanism do not fall near the line representing the compensation effect. Thus the analysis of the kinetics data provides a good diagnostic tool for understanding the fundamental chemistry of the acid-catalyzed hydrocarbon conversions.
Date: December 31, 1996
Creator: Gates, B.C.
Partner: UNT Libraries Government Documents Department

Superacid catalysis of light hydrocarbon conversion. Ninth quarterly report, October 1, 1995--December 31, 1995

Description: Transition metal promoters of sulfated zirconia increase its catalytic activity for the conversion of n-butane. The promoter effects vary from one transition metal to another in the family zinc, iron, nickel, cobalt, and manganese. The most active catalyst so far tested is promoted by both iron and manganese. This catalyst is two or more orders of magnitude more active than unpromoted sulfated zirconia. The manganese promoter alone markedly increases the catalytic activity, but the activity declines very rapidly with time on stream in the flow reactor. Under the same experimental conditions, iron has a smaller but longer-lasting effect as a promoter than manganese, and to a first approximation, the iron- and manganese-promoted catalyst shows a behavior that is a superposition of those of the two individual promoters.
Date: December 31, 1995
Creator: Gates, B.C.
Partner: UNT Libraries Government Documents Department