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Articles 871 - 900 of 969
Full-Text Articles in Chemical Engineering
Zone Refining Of Anthracene, Charles Poultney Perot
Zone Refining Of Anthracene, Charles Poultney Perot
Theses
The process of zone refining involves the passage of a molten zone along a rod of solid. As the zone progresses, composition of the material freezing out generally differs from that melting, so solutes are redistributed. Enrichment of the major component occurs toward one end of the rod. (Usually the end of frozen.)
In the present work, impure anthracene was subjected to zone refining. Feed first run was C.P. anthracene with a known impurity of 2.0% phenanthrene. After two passes no phenanthren was detectable in the first layer frozen. (Analysis was by ultra-violet spectrophotometry.) Although the zones melted out were …
Recovery Of Phthalic Acid, George Thomas Roberts
Recovery Of Phthalic Acid, George Thomas Roberts
Theses
Crude phthalic acid from the fusion processing of alkyd resins was found to be recoverable by solvent extraction, neutralization-acidification, sublimation, distillation, esterificatton with monohydric alcohols, ion exchange or alkyd resin preparation.
The author proposes that alkyd resin preparation, based on analysis of the crude phthalic acid, is the most practical way for the alkyd resin manufacturer to recover the crude phthalic acid. No purification of the crude phthalic acid is necessary for this utilization and the resulting alkyd resin is saleable at a profit.
The Rates Of Hydrolysis Of Aryl Halides, Jack Robert Roeder
The Rates Of Hydrolysis Of Aryl Halides, Jack Robert Roeder
Theses
The object of this work was to determine the relative activity of the halogens, chlorine, bromine and iodine toward hydrolysis in a water-soluble aryl halide in which the halogen is activated by a nitrogroup in the orthoposition.
The order of activity was found to be C1) POI. In the case of the chlorine compound a run was also made on sodium 2-chloro-5-nitrobenzenesulfonate in which the nitro group is in a pare position with respect to the halogen.
The preparations of sodium or potassium 4-chloro-3-nitrobenzene sulfonate (I), sodium or potassium 4-bromo-3-nitrobenzene sulfonate (II), sodium or potassium 4-iodo-3-nitrobenzene sulfonate (III), and sodium …
Exchange Adsorption Of Electrolytes On Titanium Dioxide, Richard Algimantas Slepetys
Exchange Adsorption Of Electrolytes On Titanium Dioxide, Richard Algimantas Slepetys
Theses
During the manufacture of titanium dioxide pigments many processing steps are carried out in solutions of electrolytes. Adsorption of these electrolytes strongly affects properties of the finished pigments.
Adsorption of electrolytes Was studied on titania samples prepared by controlled neutralization of titanium tetrachloride solutions with ammonium hydroxide, and one sample of commercial sulfate process rutile titania. In analogy to zirconia--as reported by Kraus and Phillips?22,23 titania also behaved as a weak anion exchanger in acid solutions and as a weak cation exchanger in basic solutions. Acid or base liberated was approximately equivalent to ions exchanged. On the best sample …
Self-Heating Of Wood Fiber, Kenneth Norman Smith
Self-Heating Of Wood Fiber, Kenneth Norman Smith
Theses
An investigation was made to determine what portion of wood is responsible for the self-heating of wood fiber, where self-heating is defined as the increase in temperature of a material above the temperature of its surroundings due to an exothermic reaction occurring within the material. The phenomenon of self-heating of wood fiberboard has long been known, but very little has been done to discover the particular part of the wood which generates the heat.
Wood fiberboard was tested for self-heating by placing a. cubical sample in a specially constructed furnace and heating it to a uniform temperature of 325?F. As …
Continuous Chlorosulfonation Of Benzene Ii Phase Relations, Ernest Eugene Wiegleb
Continuous Chlorosulfonation Of Benzene Ii Phase Relations, Ernest Eugene Wiegleb
Theses
This work presents data for the separation of materials involved in the chlorosulfonation of benzene using carbon tetrachloride as an inert extraction solvent. Equilibrium and tie line data for the liquid ternary systems; carbon tetrachloride chlorosulfonic acid - sulfuric acid; Benzenesulfonyl chloride - carbon tetrachloride - sulfuric acid; benzenesulfonyl chloride ehiorosulfonic acid - sulfuric acid and for the quaternary system benzenesulfonyl chloride - carbon tetrachloride chlorosulfonic acid - sulfuric acid have been determined. The tie line data has been correlated by the method of Othmer and Tobias.
Data for two chlorosulfonations made under differing conditions is also given.
Thermodynamic Properties Of Monochlorobenzene, Gaetano Zaccaria
Thermodynamic Properties Of Monochlorobenzene, Gaetano Zaccaria
Theses
The thermodynamic properties of saturated and superheated monochlorobenzene were evaluated at ten degree temperature intervals from 0°C to 750°C and at various pressures up to 300 atmospheres.
Equations relating the specific heat, the vapor pressure, and the density with temperature, were derived from the data available in the literature. They were used together with generalized charts to evaluate the thermodynamic properties.
The values for temperature, pressure, specific volume, enthalpy, and entropy for saturated and superheated monochlorobenzene are presented in the form of tables.
An Investigation Of The Hofman Reaction As A Possible Method Of Synthesizing 3,4-Diamino Pyridine, Harry William Zbinden
An Investigation Of The Hofman Reaction As A Possible Method Of Synthesizing 3,4-Diamino Pyridine, Harry William Zbinden
Theses
This study presents an attempt to evaluate the Hofman degradation as a method of synthesizing 3,4-diamino-pyridine from isoquinolinic acid. Since the pyridine ring is known to he stable under the reaction conditions, and analogous aromatic diamides have been prepared by previous investigators, the major problem studied is the effect of hypohalites on ortho-oriented aromatic diamides.
Three methods of approaching the problem were unsuccessful in producing the desired diamine, but the last method, stepwise degradation of each group separately, may be workable with some changes.
The most significant result was the observation of an unexpected side reaction when the diamide was …
Viscosity Of A Three Component System, Acetone-Ethanol-Water, At 25°C And 30°C, Peter Fred Widmer
Viscosity Of A Three Component System, Acetone-Ethanol-Water, At 25°C And 30°C, Peter Fred Widmer
Theses
The viscosity in the three component system Acetone-Ethanol-Water has been determined over a range of compositions at two different temperatures, 25°C and 30°C. Compositions have been varied in increments of ten percent by weight to cover all possible combinations of the three components. The data obtained are presented on triangular coordinate graph paper with lines of constant viscosity indicated and also in tabular form.
Aryl Sulfonation In Presence Of Phosphrous Trichloride, William Calvert Tanner
Aryl Sulfonation In Presence Of Phosphrous Trichloride, William Calvert Tanner
Theses
With sulfuric acid as the sulfonating agent, phosphorus trichloride is demonstrated as being effective in facilitating the sulfonation of some aromatic compounds. Optimum conditions are a molar ratio of 0.5 mole of sulfuric acid: 1.0 mole of aromatic compound with 4 - 5% more phosphorus trichloride than is required to react with the available water in the system, and reaction temperatures between 50°C. and 60°C.
The aromatic compounds studied were benzene, chlorobenzene, bromobenzene, and nitrobenzene.
The Use Of Perlite As An Adsorbent, John Herrick Eigler
The Use Of Perlite As An Adsorbent, John Herrick Eigler
Theses
The adsorptive properties of perlite, an expanded volcanic glass, have been studied. Several activating treatments were investigated, air oxidation it 400 degrees Centigrade appears to be the best, The adsorption of the basic dye emethylene blue yields a saturation valve of 50 milligrams per gram of perlite. The acid dye cotton blue showed no measurable adsorption. A maximum adsorption of 15 millimoles of acetic acid and one milligram of iodine were found in aqueous solution. A high value of 1.33 milligrams of iodine per gram of perlite were found in methyl alcohol solutions. The surface area of perlite appears to …
Liquid-Gas Flow In Venturi Meter And Sharp Edged Orifice, Frank John Chwalek
Liquid-Gas Flow In Venturi Meter And Sharp Edged Orifice, Frank John Chwalek
Theses
The results of a study of pressure drops across a 5/32 inch throat venturi meter and a 5/32 inch thin plate sharp-edged orifice for the horizontal cocurrent, flow of the air-water two-phase two-fluid system in a 3/4 inch pipe under essentially isothermal conditions, are presented. This is the first critical study of two phase flow in a Venturi meter and. in a 5/32" orifice.
Flows of water of 0.1 to 1.7 gallons per minute with air rates in range of 0.00022 lbs/sec. to 0.0092 lbs/sec. of air mixed in were studied. All flows were turbulent when judged with the conventional …
Hydrolysis Of Sodium Silicofluoride, Frank Arthur Graf
Hydrolysis Of Sodium Silicofluoride, Frank Arthur Graf
Theses
The kinetics of an apparent solubility decrease of commercial sodium fluoride encountered in a piece of equipment designed to produce saturated sodium fluoride solution was Investigated, in order to understand why a consistently saturated solution was not possible to achieve with plain tap water as solvent.
The main impurity, about 1 percent sodium silicofluoride, coats the sodium fluoride crystals, resulting in an equilibrium shift during dissolution of the salt in water; and under certain conditions results in the formation of a protective gel. Therefore, in order to produce a constant strength sodium fluoride solution, this coated impurity must be decomposed …
The Preparation Of 3,4-Diaminopyridine, Emil John Fencl
The Preparation Of 3,4-Diaminopyridine, Emil John Fencl
Theses
The preparation of 3,4-diamincpyridine from pyridine was investigated, but found to be of little synthetic value because of the low yield obtained on the rearrangement of 4-nitraminopyridine to 3-nitro 4-aminopyridine. In attempt to nitrate nicotinamide-N-oxide resulted in the isolation of nicotinic acid-N-oxide. Attempts to nitrate nicotinic acid-N-oxide were unsuccessful. Attempts to oxidize 3-methylpyridine-N-oxide and 4-nitro-3-methylpyridine were unsuccessful. The nitration of 3-methylpyridine-N-oxide led to the isolation of 2-nitro-5-methylpyridine, which has not previously been reported as a by-product of that reaction.
Ammonia Catalized Phenol Formaldehyde Resins, Murlin Charles Ehrgott
Ammonia Catalized Phenol Formaldehyde Resins, Murlin Charles Ehrgott
Theses
The literature on ammonia-catalyzed phenol-formaldehyde resins is reviewed and critical comparisons are made of the manner in which the ammonia-catalyzed resins differ from both the alkali- and acid-catalyzed resins.
Intermediate products formea during the initial stapes of the ammonia-catalyzed phenol-formaldehyde reactions, as reported in the literature, are tabulated and % N contents are calculated.
Experimental determinations of N content of resins with molar ratios of 1:1.25 phenol to formaldehyde with ammonia at 0.2, 0.5, and 1.0 moles per mole of phenol, show that at the 0.2 molar ratio of ammonia, all the N enters into the resin and remains during …
Heat Transfer Coefficients In An Agitated Vessel Using Verticle-Tube Baffles, Edward Joseph Barrasso
Heat Transfer Coefficients In An Agitated Vessel Using Verticle-Tube Baffles, Edward Joseph Barrasso
Theses
Data are presented to show the effect of impeller speed, impeller type, and fluid properties on the forced-convection film coefficient of heat transfer for verticle tubes in a cylindrical vessel. A generalized equation to predict the film coefficient of heat transfer on the outside of verticle tubes in an agitated vessel for both cooling and heating is also presented. This equation may be used to estimate the necessary areas of heat transfer for verticle tubes in an agitated vessel within the degree of accuracy required from most engineering calculations.
This study was the first initiated to develop an equation to …
Electrodeposition Of Cellulose And Carboxy-Methylcellulose, Charles Edward Driesens Jr.
Electrodeposition Of Cellulose And Carboxy-Methylcellulose, Charles Edward Driesens Jr.
Theses
The previous work done by Frank Cozzarelli on the eleotrodeposition of cellulose from a sodium zincate-urea-cellulose system has been verified, except that zinc was found to deposit on the cathode at all voltages and current densities within the range of the optimum conditions for deposition. The optimum conditions are: voltage - 1.10 to 1.28 volts; current density 0.13 to 1.10 amperes/square foot; electrode material - copper. Current efficiencies range from 0.80 to 5.53%.
A chelate-like complex formed from the sodium zincate and urea which couples with the cellulose has been proposed as a possible explaination of the mechanism governing the …
Activity Coefficients Of Gases In Binary Mixtures, John Gressler Engleman
Activity Coefficients Of Gases In Binary Mixtures, John Gressler Engleman
Theses
The theory and usefulness of vapor phase activity coefficients have been developed. The equations, charts and calculation procedures to be used for the three methods are included with a set of sample calculations in their most convenient form.
Activity coefficients for 236 experimental points have been calculated by the three methods for both components of tour binary gaseous systems. These systems are Argon - Ethylene (36 points), Hydrogen - Nitrogen (32 points), Methane - Ethane (112 points) and Methane - n Butane (56 points). Wide ranges of pressure, temperature and mol fraction are included.
The % deviations of calculated from …
Transesterification Of Alkyl Borates, Garry Gustav Eichmann
Transesterification Of Alkyl Borates, Garry Gustav Eichmann
Theses
An attempt was made to prepare pure methyl borate by an ester interchange using a high-boiling alkyl borate in combination with methyl benzoate or methyl phthalate. The product, assumed to be methyl borate, boiled at about 70°C., which is 5° higher than the expected boiling point, and analyzed at 88 to 95%.
Various catalysts, such as hydrochloric acid, sodium methoxide, p-toluene sulfonic acid, aluminum isopropoxide, and aluminum chloride, were tried before magnesium-aluminum ethoxide was chosen as the best catalyst for this particular tranesterification reaction.
The Fatty Acid Alkanolamide Reaction, Julius Galender
The Fatty Acid Alkanolamide Reaction, Julius Galender
Theses
An alkanolamide detergent can be formed by the condensation of coconut fatty acid and diethanolamine. A great many factors can influence this formation. It is shown that varying the molar ratio of amine to acid, results in a change in the fraction of acid converted. It similarly affects the molar quantities of amine converted. Molar conversion of acid or amine is dependent upon the type of atmosphere in the reaction; more acid is converted when a nitrogen sweep is employed than when it is not used. However, proportionately more amine is converted, when a nitrogen sweep is not used. When …
Power Requirements In Pigment Comminution, Joseph Timothy Gildersleeve
Power Requirements In Pigment Comminution, Joseph Timothy Gildersleeve
Theses
The results of this work prove that the relation between total work and surface area developed in the wet grinding of pigments is an exponential function. The following equations were experimentally determined for the pigments studied:
For Zinc Oxide; P = .090 (Δs)1.05
For Titanium Dioxide: P = .086 (Δs)1.072
For Calcium Carbonate: P = .107 (Δs)0.98
This work shows that in the grinding of sub-sieve size pigments the Rittinger and Bond theories which state that surface area developed is directly proportional to total work, are not valid and cannot be applied.
It is also shown in another plot that …
Composting Coffee Waste, Lawrence James Hickey
Composting Coffee Waste, Lawrence James Hickey
Theses
Disposal of waste, and specifically organic waste, has become a serious problem in such industries as the canning, meat-packing, dairy and other food producing industries. Recently, with the introduction of instant coffee powder, this particular industry now has a waste disposal problem with the resultant coffee residue. Composting or biologically decomposing this waste to yield an organic fertilizer is one of the many ways to solve this problem.
There are no papers in the literature concerning composting of coffee waste and only one paper (65) is available covering studies of high rate composting of garbage and refuse. It is known …
Heat Transfer Coefficients Of Condensing Vapors, Charles Rocco Lipuma, Earl Adolph Nirmaier
Heat Transfer Coefficients Of Condensing Vapors, Charles Rocco Lipuma, Earl Adolph Nirmaier
Theses
The film coefficients of heat transfer for vapors condensing on a single horizontal tube have been measured for methyl, i-propyl, and n-butyl alcohols. The equipment used was specifically designed for these studies, and represents an improvement over that used by other investigators. The data collected were analyzed usingmodified Wilson method which is based on a rigorous theoretical analysis.
It has been found that the condensing film coefficients for methyl and i-propyl alcohols vary with the heat duty. This is to be expected from the analysis mentioned above. Me variation was found for n-butyl alcohol.
The observed values of the heat …
The Condensation Of Vapors From Gas-Vapor Mixtures, Stanley Anthony Mruk, William Charles Kraemer
The Condensation Of Vapors From Gas-Vapor Mixtures, Stanley Anthony Mruk, William Charles Kraemer
Theses
Superheated mixtures of cyclohexane vapor and nitrogen gas were passed at various rates downward through a single tube condenser with the cooling water flowing countercurrently in an annular space outside the condenser.
The method of Colburn and Rougen for the design of cooler-condensers was applied and the calculated condenser lengths are compared to the experimental length.
Relatively good agreement with the design method was found for cases where there was little or no streamline flow of the gas-vapor mixture in the condenser. With increasing amounts of streamline flow* the design method tends to be increasingly conservative.
The Three Phase System N-Hexane - Aniline - Water, Charles S. Potosnak
The Three Phase System N-Hexane - Aniline - Water, Charles S. Potosnak
Theses
This is a study of the three phase system - n-Hexane Aniline - Water at 50° Centigrade. The data obtained, coupled with data previously established at 36° Centigrade is used to predict a means of recovering aniline from 3-5% aqueous solutions by scrubbing with n-hexane.
Thermodynamic Properties Of Trimethylamine, John Bernard Riley
Thermodynamic Properties Of Trimethylamine, John Bernard Riley
Theses
The thermodynamic properties of trimethylamine have been evaluated at temperatures from 32°F to 600°F and from the saturation pressure to 2000 lb/in2 based on available experimental data. An equation relating the pressure, volume and temperature of the system has been derived for the range in which experimental data were available and it was used to evaluate the thermodynamic properties in this range. Values for pressure, volume, temperature, enthalpy and entropy have been presented in the form of tables and graphs.
Effect Of Concentration On The Mass Transfer Coefficient In The Liquid Film, Marvin Baker Schaffer, Philip Major Pomerantz
Effect Of Concentration On The Mass Transfer Coefficient In The Liquid Film, Marvin Baker Schaffer, Philip Major Pomerantz
Theses
The effect of liquid concentration on the resistance to mass transfer across the liquid film is studied for an acetone-methyl isobutyl ketone-air system in a packed tower. The liquid film resistance is computed by measuring the overall resistance for various concentrations and subtracting the gas film resistance. The gas film resistance is determined at the same liquid and gas rates by measurements on the pure components.
In the theory developed to handle the calculations, it is assumed that the interface temperatures are the wet-bulb temperatures based on a dynamic equilibrium. This supposition is supported experimentally at a liquid rate of …
A Study Of The Functional Stability Of Sunscreen Compounds, Jesse Howard Starkman
A Study Of The Functional Stability Of Sunscreen Compounds, Jesse Howard Starkman
Theses
Previous work reported in literature, indicates that commercial sunscreen compounds were subject to breakdown on exposure to ultraviolet radiation with consequent change in their functional efficiencies.
These findings ware retested under conditions more closely approximating actual usage.
A new method of evaluation which closely correlates to actual experience in large scale usage, was applied. This method provides, from simple spectral data, a reliable index of physiological efficiency of the sunscreen compound. As a result, twelve commercial sunscreen compounds were exposed to ultraviolet radiation for varying periods. Analysis indicated that, contrary to the previous reports, no significant Changes in physiological efficiency …
Correlation Of Curtis And Gullett Equation For Viscosity Of Non-Newtonian Suspensions And Franks And Rinaldi Equation For Heat Transfer Coefficients, Irene S. Wisla, John L. Kukowski
Correlation Of Curtis And Gullett Equation For Viscosity Of Non-Newtonian Suspensions And Franks And Rinaldi Equation For Heat Transfer Coefficients, Irene S. Wisla, John L. Kukowski
Theses
Curtis and Gullett (7) developed an equation correlating the effect of velocity, concentration and particle size on apparent viscosity of non-Newtonian water slurries.
μ/μw=1.02(AK/GC).105
The object of this paper was to determine the validity of using the viscosity, as determined by the Curtis-GulLett (7) equation, in predicting the heat transfer coefficient of non-Newtonian fluids, where the suspending medium is something other than pure water . The authors used various concentrations of sugar solutions as the dispersion medium, for the slurries.
A dimensionless equation resembling the flittusBoelter equation with modified exponents and additional dimensionless groups has been developed …
A Study Of The Partial Oxidation Of Monosubstituted-P-Xylenes, Frederick John Honold
A Study Of The Partial Oxidation Of Monosubstituted-P-Xylenes, Frederick John Honold
Theses
In the oxidation of 2-nitro-p-xylene (I) using alkaline potassium permanganate, the only product isolated was 2-nitro-terephthalic acid (II). Approximately half of the starting material was oxidized. The other half remained as unreacted starting material.
The chromium trioxide oxidation of 2-nitro-p-xylene (I) in glacial acetic acid, using sulfuric acid as a catalyst, yielded only 3-nitro-p-toluic acid (III).
The chromium trioxide oxidations, of 2-N-acetylamino-p-xylens (IV) with and without sulfuric acid catalyst, yielded no oxidation products which could be identified. About half of the starting material was recovered in each case.
In a low temperature alkaline potassium permanganate oxidation of 2-N-acetyIamino-p-xylene a small …