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Articles 541 - 570 of 969
Full-Text Articles in Chemical Engineering
A Study Of The Effect Of An Electric Potential On The Saponification Of Ethyl Acetate, Michael Maciupa
A Study Of The Effect Of An Electric Potential On The Saponification Of Ethyl Acetate, Michael Maciupa
Theses
A reactor of rectangular cross-sectional, area was constructed of plexiglass to study the effect of an electric potential on the saponification of ethyl acetate with sodium hydroxide. Three different laminar region flow rates were used and the applied voltage was varied up to four kilovolts in one kilovolt increments for each flow rate. It was found that the apparent rate constant for the reaction was either increased or decreased depending on the voltage and flow rate used. The largest increase was a 4.2 percent change from zero voltage steady state conditions with an applied voltage of one kilovolt at a …
Adsorption On Activated Flyash, John William Kubarewicz
Adsorption On Activated Flyash, John William Kubarewicz
Theses
An experimental study was undertaken to compare the adsorptive characteristics of activated carbon, flyash, and activated flyash. Due to the contradictory evidence available in the literature, emphasis was placed on the effect of acid activation on the physical properties of the adsorbent. The experiment consisted of two parts; batch isotherm studies, and continuous column operations. An artificial sewage composed of a mixture of deionized water and beef broth was used as the adsorbate. This solution was prepared daily and exerted a COD of 225 ± 30 mg/l. Flyash activation was found to increase the degree of adsorption indirectly rather than …
The Chemical Effect Of Ultrasound On Cyanide Solutions, Nabil R. Zaki
The Chemical Effect Of Ultrasound On Cyanide Solutions, Nabil R. Zaki
Theses
An experimental study was undertaken to investigate the chemical effects of high intensity ultrasonic radiation on cyanide solutions. The effects of aeration, concentration of cyanide and temperatures on the reaction rate are investigated. The experiment was preformed in a 30 mm pyrex tube immersed at a fixed height in a constant volume water bath. Ultrasonic energy was applied through the use of a transducer epoxied at the bottom of the water bath. The power inputs to the transducer were 40W (27KHz) and 100W (21KHz).
At a power of 40W, ultrasound had no chemical effect on cyanide solutions. At 100W, hydrogen …
Computer Program For Binary Distillation Using The Method Of Pochon-Savarit With Enthalpy Data Calculated By Lagrange Interpolation, Joseph J. Rogus
Computer Program For Binary Distillation Using The Method Of Pochon-Savarit With Enthalpy Data Calculated By Lagrange Interpolation, Joseph J. Rogus
Theses
This thesis presents a Fortran Computer Program to solve binary distillation problems. The solution is obtained by the method of Pochon-Savarit which is based upon graphical use of an enthalpy-concentration diagram. The enthalpy data in this program is calculated using Lagrange interpolation. This is accomplished by utilizing the Lagrange interpolation to get values for the enthalpy of the vapor until we find that value which lies on the same line as the enthalpy of the liquid from the preceding tray and its corresponding del point.
The required input data consist of liquid-vapor equilibrium data, heat of solution data with the …
The Thermodynamics Of Electrolytic Solutions, Eric Robert Bixon
The Thermodynamics Of Electrolytic Solutions, Eric Robert Bixon
Theses
The thermodynamic properties of solutions of electrolytes may be accurately determined by the measurement of the activity of the s6lvent. when the. solute is nonvolatile, this quantity may be obtained from measurements of the lowering of the vapor pressure caused by the presence of the dissolved solute.
An experimental method has been devised to measure this effect using a semi-conventional Othmer Still. The experimental apparatus has been constructed. and evaluated. Data has been-obtained for the vapor pressure lowering of methanol due to the presence of dissolved electrolyte for five different electrolyte-methanol systems. An extrapolation technique was developed to make use …
Separation Of Isomers Via Thermal Parametric Pumping, Vincent J. D'Emidio
Separation Of Isomers Via Thermal Parametric Pumping, Vincent J. D'Emidio
Theses
Continuous and semicontinuous thermal parametric pumps for separating isomers were experimentally investigated using the model system glucose-fructose-water on a cation exchange resin adsorbent. A comparison was made between the experimental data and the calculated results by a method based on an equilibrium theory. The method invokes the assumptions that a multicomponent mixture contains a series of pseudo binary systems. Each binary system consists of one of the solutes as one component and the common inert solvent as the other component. It has been shown that under certain conditions, the pump with feed at the enriched end has the capacity for …
A Preliminary Study Of The Thermodynamic Limitations Of The Nrtl/Lemf Equations, Robert Petrie
A Preliminary Study Of The Thermodynamic Limitations Of The Nrtl/Lemf Equations, Robert Petrie
Theses
Analytical evaluations of the second and third derivatives of the molar Gibbs energy of mixing for the NRTL/LEMF equations indicate distinct zones of miscible and inmiscible prediction.
These calculations for a number of different α's have produced approximate miscibility limits for both NRTL/LEMF energy parameters and infinite dilution activity coefficients of a given system.
Transient Phenomena Of Polymer Solutions, Nikolaus Zwetkow
Transient Phenomena Of Polymer Solutions, Nikolaus Zwetkow
Theses
With the aid of a rotational viscometer, several transient phenomena were studied with different polymer solutions. In order to be acquainted with the operations of the rotational viscometer, viscosity measurements were made on polystyrene solution of a 7.14 wt. % NBS-2-35967 in a 35 - 65 mixture of aroclor and TCP, polyisobutylene (16.5% in mineral spirits), Indopol H-1900 (polyisobutylene) and 4.5% polyisobutylene in Primol 355. All these were done at a temperature of 77°F, except for Indopol H-1900 which was done at different temperatures. The results are listed in the section of tables and graphs.
Viscosity was measured with a …
The Thermal Dehydration Of Magnesium Sulfate Hexahydrate (Mgso3.6h2o) And Magnesium Sulfite Trihydrate (Mgso3.3h2o), Raafat F. Abdel-Malek
The Thermal Dehydration Of Magnesium Sulfate Hexahydrate (Mgso3.6h2o) And Magnesium Sulfite Trihydrate (Mgso3.3h2o), Raafat F. Abdel-Malek
Theses
The thermal dehydration of MgSO3.3H2O and MgSO3.6H2O have been studied by differential thermal analysis, differential scanning calorimetry and thermal gravimetric analysis.
Similar studies by other groups led to contradictory conclusions. In this investigation, these results were reconciled and it was concluded that MgSO3.6H2O, under equilibrium conditions, dehydrates in two steps through the intermediate formation of MgSO3.3H2O.
One consequence of this work is the development of a simple analytical procedure, using TGA, for the quantitative determination of both hydrates in mixtures and in the presence …
Steady State Heat Transfer From A Double Ring Of Identical Spheres In A Regular Orientation, Evelio A. Melo
Steady State Heat Transfer From A Double Ring Of Identical Spheres In A Regular Orientation, Evelio A. Melo
Theses
Solutions to Laplace's equation are obtained by the method of reflections for the problem of heat transfer from two parallel rings of spheres arranged in regular polygonal arrays. The mathematical models developed describe the rate of heat transfer and spatial temperature distribution due to an arbitrary number of identical spheres of equal surface temperature correcting Fourier's heat transfer equation for the interference caused by a multiparticle array. Although the method of solution is quite rigorous and can be used to obtain as accurate a solution as desired, only the second reflection was obtained, yielding a first order correction. The model …
Reactions Of Para-Nitroaniline With Acid Chlorides, Stephen Alan Zapoticzny
Reactions Of Para-Nitroaniline With Acid Chlorides, Stephen Alan Zapoticzny
Theses
Para-nitroaniline was reacted with acid chlorides forming amides. Their structures were elucidated by the performance of various spectral analyses.
A Kinetic Study Of Lysine And Lysine Derivatives, Stephen Joseph Stanley
A Kinetic Study Of Lysine And Lysine Derivatives, Stephen Joseph Stanley
Theses
The kinetics of the reaction of iodoacetamide with lysine, polylysine, N-α-Acetyl lysine, and N-ε-Acetyl lysine, have been studied. The investigation was done at 23° C ± 123° C, as a function of pH, and concentration. In all cases it was noted that the rate of reaction increased as the pH increased. The rate data was analyzed in order to obtain the second order rate constants. In addition, the effects of the reactive site's environment on the rate was demonstrated.
Characterization Of Thixotropic Materials And Modification Of The Weissenberg Rheogoniometer, Paul Joseph Orosz
Characterization Of Thixotropic Materials And Modification Of The Weissenberg Rheogoniometer, Paul Joseph Orosz
Dissertations
A Weissenberg Rheogoniometer, Model R-18, was modified to give complete rheological curves without resetting the gearbox and generate hysteresis loops for time-dependent, non-Newtonian materials. This modified instrument was used to analyze a number of materials. Standard Newtonian and known time-independent, non-Newtonian materials were studied to insure the accuracy of the instrument. Results indicated that the instrument would reproduce known viscosities of these materials, give consistent results, and not display inherent hysteresis loops with non-thixotropic materials. Materials known and suspected to be thixotropic: silicone grease-oil mixture, montmorillonite clay, and blood were tested. All displayed the characteristic hysteresis loop usually associated with …
Engineering A Primary Waste Treatment Plant, Edwin O. Onwawoma
Engineering A Primary Waste Treatment Plant, Edwin O. Onwawoma
Theses
This thesis deals with the design and construction of a primary waste treatment plant. The scope of work covered here, includes waste sampling and characterization, process design data gathering, process and mechanical design, cost estimate, and a general discussion of the construction and start-up.
In the development of this work, it is assumed that a decision has been made to build the waste treatment plant, using a known process. Therefore, economic evaluations designed to determine return on investment and selection of a process, will not be discussed. The impact the capital investment associated with the waste treatment facility has on …
The Interpretation Of Infrared And Raman Spectra Using Pattern Recognition, John Martin Comerford
The Interpretation Of Infrared And Raman Spectra Using Pattern Recognition, John Martin Comerford
Dissertations
An automatic classification of chemical compounds by computer processing of digitized spectral data is presented. The classification system is based on a branch of artificial intelligence known as supervised learning, and used binary linear classifiers to identify compounds as alcohols, esters, ethers, ketones or compounds containing double bonds.
Each of the 1117 spectra in volume one of Sadtler's Standard Raman Spectra was coded using a scale from 0 to 9 in the range from 4000 to 200 cm-1. One hundred and twelve readings were taken on each spectrum. These data were then examined using pattern recognition techniques, and …
Sidewise Force Exerted On Slowly Falling Spheres Inside A Circular Cylinder, Gary Mark Greenstein
Sidewise Force Exerted On Slowly Falling Spheres Inside A Circular Cylinder, Gary Mark Greenstein
Theses
Numerical values are provided for the forces that must be applied to a reference sphere to prevent its sidewise motion when two equal-sized spheres settle through a viscous liquid bounded by a cylindrical tube. These values are presented for two independent set of circumstances:
- - the spheres are translating but not rotating
- - the spheres are rotating but not translating
Forces have been calculated assuming various distances between the sphere centers and with the line of centers at various angles to the horizontal. The results are discussed for the case where the spheres are both translating and rotating and compared …
Effect Of Mixing On Polymerizations In Batch Reactors, John Guy Steenrod
Effect Of Mixing On Polymerizations In Batch Reactors, John Guy Steenrod
Theses
The effects of mixing on polymerizations in batch reactors are examined theoretically for initiations by thermal decomposition of catalyst and by absorption of ionizing radiation. Mathematical expressions for predicting the first three moments of the dead polymer size distribution are presented. Two extreme mixing states. perfect and no mixing. are considered. It is shown that in batch reactors mixing in any direction in which nonuniform initiations exist increases the polymerization reaction rate and the number average molecular weight, and decreases the weight average and the polydispersity.
Experimentally, the effects of mixing were studied in a solution polymerization system, in a …
Evaluation Of Herington General Integral Test For Vapor-Liquid Equilibrium Data, Raja Gopal Nori
Evaluation Of Herington General Integral Test For Vapor-Liquid Equilibrium Data, Raja Gopal Nori
Theses
A new set of general integral tests for the thermodynamic consistency of isothermal and isobaric equilibrium data of binary systems was proposed by E.F.G. Herington.
The systems Benzene-Cyclohexane and Benzene-n-Propanol were examined using Herington integral test-. The data used included sets of data known to be in error. One set was, in effect, at true vapor-liquid equilibrium (the data of literature) but the other data was obtained when the system was inadequately insulated and heated.
Heringtan test showed significantly different estimates for heats of mixing for the cases involved. The best data showed heats of mixing near the theoratical values. …
Rheo-Optical Properties Of Polyisobutylene, Russell B. Biss
Rheo-Optical Properties Of Polyisobutylene, Russell B. Biss
Theses
This study presents quantitative experimental data on the various stress-optical characteristics of polymer liquids, specifically, polyisobutylene. Through the use of a concentric cylinder rheogoniometer and a rotational viscometer, the temperature effects of a newtonian polyisobutylene liquid. was studied and was found to have a stress-optical coefficient independent of shear stress and minor temperature changes. The experiments confirm that the birefringence is a known function of the extinction angle and the shear stress. Various polyisobutylene liquids were used in a simple flow device to observe the birefringence in the 1-3 plane and the 2-3 plane. The results indicate that the 1-3 …
A Study Of An Adiabatic Tubular Reactor For The Multiple Chlorination Of Methane, Richard L. Braun
A Study Of An Adiabatic Tubular Reactor For The Multiple Chlorination Of Methane, Richard L. Braun
Theses
A computer program has been developed which simulates the multiple chlorination of methane in an adiabatic, tubular reactor. Euler's method is used to approximate the solutions of the programs differential equations.
The program is designed to determine the amount of an inert diluent required in the feed stream to attain some specified conversion of methane in a safe and efficient temperature range. Particular emphasis is put on determining the amount of diluent required to attain 98% conversion of methane at an outlet temperature of 723°K. The program also determines the reactor volume necessary to achieve the specified conversion, and the …
The Steady State Heat And Temperature Distribution Of A Hot Sphere Within An Infinite Wedge, David W. Horwat
The Steady State Heat And Temperature Distribution Of A Hot Sphere Within An Infinite Wedge, David W. Horwat
Theses
This thesis presents a mathematical model of the steady state heat and temperature distributions of a hot sphere located along the midplane of an infinitely long wedge of any arbitrary central angle. The heat and temperature distributions of this geometric configuration are of immense value, since through the use of this model as a wedge shaped unit cell the description of any number of hot spheres, arranged in a regular planar array can be immediately determined.
The method of reflections is used to solve Laplace's equation , V2T=O , analytically using the sphere and the wedge walls as …
The Study On The Soot Formation Of Hydrocarbon Flames, Yih-Jian Wu
The Study On The Soot Formation Of Hydrocarbon Flames, Yih-Jian Wu
Theses
Carbon formation during the quenching of low-pressure premixed hydrocarbon flames was studied using rapid-scanning optical and mass spectroscopy. Experimental techniques were developed and it was found that the tendency to form soot was a function of the hydrocarbon chain length. These results are relevant to the design of restartable space engines in which the use of hydrocarbon fuels is contemplated because the formation of soot in space will result in the formation of a shroud around the spacecraft which will adversely affect sensing by optical means.
Solvents Screening For Hydrocarbons Separation Of Close Molar Volumes, Dilip K. Kapasi
Solvents Screening For Hydrocarbons Separation Of Close Molar Volumes, Dilip K. Kapasi
Theses
The approximate physical model for solute-solvent inter?actions presented by J, M, Prausnitz and R, Anderson1 is briefly discussed, Applicability of Weimer, Prausnitz3 and Helpinstill, Van Winkle7 models is investigated using experimental values of activity coefficients for C5 hydrocarbons in 13 solvents including one nonpolar and 12 polar solvents. Independent correlations, based on our experimental values at 45°C for normal and isopentane have been developed. Although the required thermodynamic properties are obtained through a comparative analysis of all the available and estimated methods, dependable values of activity coefficients for Isopentane and 1-Pentene could not be obtained through …
The Effect Of Dry-Blending High Density Polyethylene On Final Product Properties, Charles H. Klestadt
The Effect Of Dry-Blending High Density Polyethylene On Final Product Properties, Charles H. Klestadt
Theses
The incentives for Dry-Blending Polyethylenes of varying property type may be economic gain, improved product quality, or both. The manufacturers' latest mode of operation involves seeking to meet their customers' needs with a product line made by using one catalyst system and operating at maximum capacity, while varying the fewest possible control parameters. Off-spec materials and on-spec materials not fitting customers' requirements are two prime targets for additional profits with proper dry blending techniques. The approach used in solving the problem involved starting with an existing product line and converting these products into a number of experimental blends. The blends …
Optimal Performance Of Equilibrium Parametric Pumps, Joseph A. Manganaro
Optimal Performance Of Equilibrium Parametric Pumps, Joseph A. Manganaro
Theses
An examination of the conditions required to obtain the optimal performance of semicontinuous and continuous parametric pumps, defined by the achieving of the maximum possible solute free product for a given column height, was undertaken. The model system sodium nitrate ? water on an ion retardation resin adsorbate was employed. Equations defining maximum values of certain important parameters such as the bottom product flow rate and reservoir displacement rate were developed by extending previous theories of parametric pumping. Experimental runs were carried out using parameters whose values were both less than and greater than the maximum values predicted for optimal …
The Determination Of An Optimum Plant Capacity In A Dynamic Economy, Frederick Louis Monesmith
The Determination Of An Optimum Plant Capacity In A Dynamic Economy, Frederick Louis Monesmith
Theses
A. Monte Carlo computer program has been developed in which the optimum plant capacity is determined by comparing calculated profitability criterions for various plant capacities. The estimates for input variables are developed into probability distributions. This data is then used to calculate a probability distribution for a-profitability criterion. In this thesis approximately thirty input variables are developed into beta distributions. Each variable must be estimated with a ninety percent probability estimate, a most likely probability estimate and a ten percent probability estimate. The three level estimates for each variable completely describe the beta distribution. Approximately half of the beta distributions …
The Thermal Degradation Of Polyvinyl Alcohol, Carlos Eduardo Ortiz
The Thermal Degradation Of Polyvinyl Alcohol, Carlos Eduardo Ortiz
Theses
The thermal degradation of polyvinyl alcohol has been investigated using mass spectrometry, differential thermal analysis, and infrared spectroscopy unlike previous investigators, formaldehyde and acrolein were not observed volatiles. In addition, acetic acid was observed, a product not reported previously.
A Nonlinear Viscoelastic Model, Yon-Li Shangkuan
A Nonlinear Viscoelastic Model, Yon-Li Shangkuan
Dissertations
A nonlinear viscoelastic model has been developed to describe the non-Newtonian viscosities and the primary normal stress differences of high polymers at steady-state shearing flow.
It has been demonstrated that the Huang-Shangkuan model gives the best representation of the experimental data for a wide range of shear rates. In the high shear rate region the Huang-Shangkuan model is distinguished among other models by its capability to predict the nonNewtonian viscosities and the primary normal stress differences Which the other models fail to predict.
Continuum mechanics, Lodge's network theory and Rouse's theory provide specific information in developing our model. The theoretical …
Effect Of Gas Temperature Gradients And Radiant Heat Transmission On Kinetic Model Behavior, Richard W. J. Robertson
Effect Of Gas Temperature Gradients And Radiant Heat Transmission On Kinetic Model Behavior, Richard W. J. Robertson
Dissertations
Satisfactory methods to predict radiant heat transmission in enclosures containing a radiating gas at uniform temperature are available. These methods have been traditionally used in solutions of kinetic models.
Kinetic models are strongly temperature dependent with a difference of 10°K able to double the reaction rate. In the present investigation, calculation techniques which make allowance for the non-uniformity of gas temperatures in an enclosure are applied to the kinetic models. The furnace problem considers only the radiation section with the assumption that detailed knowledge of combustion and fluid flow pattern within the enclosure is available.
If the gas space in …
Design Of Multipass Fractionating Trays, Paul W. Becker
Design Of Multipass Fractionating Trays, Paul W. Becker
Theses
Multipass fractionating trays are vapor-liquid contacting devices with high liquid handling capabilities which can be economically used in large fractionating towers. However, process design engineers in the chemical and petroleum industries seem to have an aversion to specifying multipass trays for their tower designs. This thesis presents the case for using multipass trays as well as methods for their design.
Because multipass trays are not symmetrical, as one and two pass trays are, the liquid and vapor need not split equally between the three or four passes. Equations are developed which enable the vapor and liquid flowrate for each pass …