Chemical Engineering Commons^™

Radial Pressure Gradient In Turbulent Pipe Flow, Gary Kent Patterson, Walter J. Ewbank, Virgil A. Sandborn

Chemical and Biochemical Engineering Faculty Research & Creative Works

Measurements made with a Prandtl static pressure probe have demonstrated that a radial pressure gradient does exist in turbulent pipe flow with approximately the magnitude predicted by Sandborn from hot-wire anemometry measurements.

Handlos And Baron Model: Short Contact Times, J. Patel, Robert M. Wellek

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.

The Anodic Dissolution Of Cadmium, James W. Johnson, E. Deng, S. C. Lai, William Joseph James

Chemical and Biochemical Engineering Faculty Research & Creative Works

The anodic dissolution of cadmium has been studied in aqueous solutions containing Cl−, Br−, I−, Ac−, SO₄=, and NO3− ions. The normal valence (+2) was found in all solutions with the exception of NO₃−. The apparent valence (calculated) of cadmium ions in nitrate solutions varied from 1.2 to 2.0 and was found to be a function of NO₃− concentration, current density, and temperature. An anodic dissolution mechanism has been proposed involving local corrosion and disintegration of the anode which is consistent with the experimental results. © 1967, The Electrochemical Society, Inc. All rights reserved.

The Effect Of Concentration On The Viscosities Of Solutions Of Linear Flexible High Polymers, Lung Yu Chou, Jacques L. Zakin

Chemical and Biochemical Engineering Faculty Research & Creative Works

Viscosity-concentration results in the moderately concentrated range for four samples of polyisobutylene (molecular weights of 1.3 x 104 to 1.0 x 106) in cyclohexane (concentrations up to 4.7 g./dl.) and in benzene (concentrations up to 7.0 g./dl.) at 24°C. (a theta solvent) showed molecular weight and goodness of solvent dependencies similar to those reported earlier for three other polymers. For polyisobutylene, polystyrene, and a copolymer of styrene and methyl methaerylate in good solvents, viscosity-concentration data plotted as ηsp. C[η] vs. k′[η]C fit a single curve. The linear region of this curve suggests that the Huggins equation is useful to C[η] …

Study Of Mass Transfer Through Porous Water-Repellent Membrane As A Function Of Membrane Thickness And Rates Of Heating, Yalamanchili Babu Rao

Masters Theses

"The object of this investigation was to study the mass transfer coefficients through porous water-repellent membranes, and their dependence on membrane thickness and rates of heating, and to compare experimental correlations with theoretically based equations. The membranes used during the experimental work were made of glass fiber treated with Teflon suspension and aluminum sulfate. The mechanism involves evaporation and condensation on opposite sides of a vapor-filled porous membrane. Salt water evaporates from one interface of a non-wettable, porous membrane, diffuses through the vapor filled pores, and condenses to fresh water at the other interface of the membrane. This transfer may …

Molecular Diffusion In Polymer Solutions By A Microinterferometric Method, Surendra V. Desai

Masters Theses

"The object of this investigation of molecular diffusion in aqueous polymer solutions was to study the effect of solute concentration on the differential diffusion coefficient and also to study the effect of polymer concentration on the mean integral diffusion coefficient. For this purpose a microinterferometric method was used. Two non-ionic, water soluble polymers, Carboxymethylcellulose (CMC) and Carboxypolymethylene (Carbopol), were used in the study with D-Glucose as a solute.

The differential diffusion coefficient was found to increase with increases in solute concentration in all cases. For CMC, the integral diffusion coefficient at first decreased with increasing polymer concentration but became constant …

Mass Transfer From A Torus Shaped Body, Kamalesh Suryakant Desai

Masters Theses

"A mathematical model for molecular diffusion in a torus was derived. Handlos and Baron have assumed a system of tori in their eddy diffusion model for liquid-liquid extraction from droplets. However, the effect of torus curvature was neglected in their studies. Since they assumed the torus could be represented by an infinite cylinder. In this study, the effect of torus curvature was considered on the concentration profile and the fraction of the solute extracted. The partial differential equation describing the model consists of three independent variables, and a finite difference technique was employed for the solution of the mathematical model. …

A Kinetic Study Of Ti⁺³ Oxidation To Ti⁺⁴ In Hydrofluoric Acid Solutions, Kuo-Shein Shen

Masters Theses

"The purpose of this investigation was to study the oxidation rate of Ti⁺³ to Ti⁺⁴ in hydrofluoric acid solutions in the absence of air. The concentration of hydrofluoric acid was varied from 0.25 to 2.00 M and the concentration of titanium from 0.05 to 0.50 M. The temperature was controlled at 25⁰C. The reaction rate was relatively slow. In most instances, less than 50 percent of the Ti⁺³ was oxidized during a period of 100 hours"--Abstract, page vii.

Velocity Profiles In Viscoelastic Drag Reducing Solutions, Luis Gustavo Florez E.

Masters Theses

"Turbulent velocity profiles in viscoelastic drag reducing solutions were measured using hot-film anemometer and Pitot tube techniques. Data were obtained in a solution of one per cent aluminium [sic] dioleate in toluene and in 0.2 and 0.4 per cent solutions of polyisobutylene (PIB) L-200 in cyclohexane. Velocity profiles were also obtained for comparison in toluene and cyclohexane by both techniques. By integrating the Pitot tube velocity profiles, large flow rate discrepancies between integrated and measured flow rates were found for the drag reducing polymer and soap solutions. This discrepancy was not observed in the hot-film anemometer measurements. The hot-film anemometer …

The Relation Of Heat Transfer To Mass Transfer In Vaporization Through Porous Membranes., Chung-Liang Yeh

Masters Theses

"The object of this investigation was to study the mass and heat transport phenomena through porous, water-repellent membranes. The investigation concerned the rate of vaporization of salt water at a porous membrane surface, mass transfer of vapor through the pores of the membrane, condensation of vapor on the other surface of the membrane in contact with a coolant (fresh water), and the undesired heat transfer by conduction through the membrane. The water-repellent membrane separated the two liquid phases by surface tension forces and provided a vapor phase in its pores. Membranes made of fiberglass and Teflon had been found suitable …

Some Aspects Of Transient Flow Behavior In Artesian Aquifers And In Hydrocarbon Reservoirs Surrounded By Artesian Aquifers, Alton John Nute

Masters Theses

"An analysis of the principal theories concerning the transient movement of water in artesian aquifers and from artesian aquifers into hydrocarbon reservoirs is presented. Various analytical methods which can be applied to depict the behavior of these two types of aquifer systems are compared.

Most aquifer studies to date have been based upon the Thesis Non-Equilibrium Formula. This equation has been used to calculate the coefficients of storage and transmissibility for aquifers; to evaluate well performance; and to investigate problems concerning recharge, movement, and discharge of aquifer water. However, one problem which still remains is that of accurately predicting the …

Study Of Mass Transfer Through Porous, Water-Repellent Membranes, Virendra V. Tanna

Masters Theses

"A new method of desalination using a porous, water-repellent membrane was studied. The membrane utilized surface forces to support a vapor phase in its pores which separated the salt water from fresh water. The method used a vapor pressure difference across the membrane as the driving force for mass transfer of water from the salt water phase to the fresh water. This vapor pressure difference was obtained by maintaining a temperature difference between the two liquid phases.

The experimental data and results indicated the feasibility of vaporization through porous, water-repellent membranes. The flux of water through a membrane made of …

The Performance Of A Countercurrent Extraction Column With Vibrated Packing, Mehmet Uran ÖZsoy

Masters Theses

"The performance of a continuous countercurrent extraction column with a packing -- that could be vibrated vertically at various amplitudes and frequencies by a variable speed motor -- was investigated under both non-flooding and flooding conditions using the high interfacial tension benzene-acetic acid-water ternary system. In all the experimental runs, which were sequenced randomly with a full-factorial experiment design, mass transfer of the solute (acetic acid) from the aqueous to the organic phase was studied. Column performance was evaluated in terms of the height of an overall transfer unit, HTU, based on the benzene phase. The variables studied were: amplitude …

Correlation Of Drag Reducing Data In Dilute Polymer Solutions, Jorge Mario Rodriguez

Masters Theses

"The purpose of this investigation was to obtain a correlation for drag reducing solutions in circular tubes under turbulent conditions. Data were taken for three polymer-solvent systems: polymethyl methacrylate V-100 (M_v ~ 110,000) in toluene, polyisobutylene L-200 (M_v ~ 4,700,000) in toluene, and polyisobutylene L-200 in cyclohexane. The data from the two polyisobutylene systems, together with other data on polymethyl methacrylate G (M_v ~ 1,500,000) in toluene and polyisobutylene L-80 (M_v ~ 860,000) in cyclohexane, were used to attempt to obtain the correlation. The V-100 solutions were not used because they were not drag reducing.

The …

The Effect Of Concentration On The Viscosity Of Polyisobutylene Solutions, Lung-Yu Chou

Masters Theses

"In the past twenty years the viscosity of dilute polymer solutions (i.e., where the solute molecules are far apart) has been investigated in great detail, both theoretically and experimentally. The viscosity characteristics of such systems are well-understood.

Only a few studies have been made of the effect of concentration on the viscosity of polymer solutions in the concentration range where the polymer molecules begin to overlap. This range of concentrations is important in practical applications such as dry spinning of fibers, cross-graded automotive motor oils and in many industrial formulations where polymers are used to thicken solvent vehicles. Development of …

The Anodic Behavior Of Zinc In Aqueous Salt Solutions, Yun-Chung Sun

Doctoral Dissertations

"The increasing demand for protective metals as coatings and non-corrosive alloys has caused extensive research on the fundamental behavior of metals in corrosive media. The problem of controlling the destructive process of metallic corrosion still exists and becomes urgent in this space age. The desirablity of metals such as beryllium, magnesium, and zinc in air frame and space structural units, because of their high strength to weight ratio, has been responsible for the considerable progress in their technology in recent years.

The basic mechanism of the anodic dissolution of metals such as zinc, cadmium, and magnesium in salt solution is …

A Study Of The Anodic Oxidation Of Acetylene On Gold Electrodes, Jo Lisle Reed

Doctoral Dissertations

"The object of this investigation was to establish a mechanism for the anodic oxidation of acetylene on gold electrodes in aqueous solutions. It is known that anodic oxidation of organic compounds on gold electrodes produces a large number of organic intermediates and end products. Therefore, it appeared worthwhile to establish a mechanism that could provide a better understanding of the fuel cell electrode kinetics and possibly lead to new methods of organic syntheses"--Introduction, page 2.

Permeability And Additive Sorption And Extraction In Lubricating Greases, Hsiu-Hsiung Lin

Masters Theses

"An important goal in the study of lubricating greases is the determination of the mechanism of additive action in lubricating greases and the effect of additive concentration on the improvement of particular properties. As a step in this direction, one aim of this investigation was an attempt to determine whether grease additives are sorbed on the thickener surface, or are dissolved in the oil phase, or if a combination of these effects prevails. Exploratory sorption and extraction experiments were run by Tu using greases thickened with lithium hydroxystearate and Baragel and using only one concentration of additive. More detailed studies …

Kinetics And Mechanisms Of Base-Catalysed Reactions, Rohit Panalal Sheth

Masters Theses

"Base-catalysed reactions normally involve complex series of transformations. their kinetics is usually governed by a variety of equilibria, participating in the overall and concurrent processes as well as by competitive side-reactions that interfere with the normal course of such reactions. Mechanisms which have been proposed, by and large, are primarily based on product, by-product and intermediate analyses together with some scattered kinetic and isotopic evidence. In the cases where kinetic studies have been attempted, highly complex mechanisms have usually been proposed due to the frequent necessity of using heterogeneous media or employing involved mathematical treatments to describe the kinetics of …

Nucleate Boiling Heat Transfer To Liquid Nitrogen At Atmospheric Pressure, Satish R. Parikh

Masters Theses

"The object of this investigation was to study the effect of micro-roughness, a thin layer of oil, and infra-red radiations on the cylindrical heat transfer surface of copper, in liquid nitrogen and at atmospheric pressure during nucleate boiling. An attempt was made to find any possible effect of orientation of the heat transfer element on nucleate boiling. A number of different runs were taken with different degrees of roughness, and different orientation positions. Nucleate boiling has been found to be nearly independent of the heat transfer surface roughness and of orientation while strongly dependent on the chemical nature of the …

Decarboxylation Of Malonic Acid In Aqueous Solutions, Ramesh Natwarlal Gujarathi

Masters Theses

"The rate of decarboxylation of malonic acid in aqueous solutions was studied over a range of concentrations, pH's, and temperatures. The catalytic effect of various divalent metallic ions was also studied at a pH of 0.3. these studies did not support a truly unimolecular decomposition as the experimental order was found to be slightly greater than one. An empirical relation for the rate of decarboxylation was formulated in which the undissociated malonic acid and the monovalent malonate ion were the reactive species.

A possible mechanism of decarboxylation due to solvent activation was postulated. No pronounced catalytic effect due to the …

Mass Transfer In Droplets With Turbulent Internal Circulation - Mathematical Description, Jayantilal Mohanbhai Patel

Masters Theses

"This investigation was carried out to check the accuracy of the eigenvalues, λ_n, calculated by Wellek and Skelland, using some method other than the Rayleigh-Ritz technique and also, to determine the coefficients, B_n in series solution, which were not calculated before.
The eigenvalues were obtained by trial and error procedure using the standard Runge-Kutta method. The coefficients B_n were obtained by using eigenvalues. By using this information the fractional extraction was calculated as a function of droplet contact time.

The Wellek-Skelland modification was also solved by finite difference technique to compute fraction extracted as a function …

Electrodialysis Of Tomato Juice, Raghunath R. Khetan

Masters Theses

"Thermal decarboxylation of carboxylic acids has been helpful in illustrating some fundamentals of reaction kinetics in solution. It has been important in formulation of the theory of unimolecular reactions. It is also used frequently in the synthetical methods of organic chemistry.

In a recent study of the anodic oxidation of malonic acid in sulfuric acid at 80⁰C using a platinum anode, the interpretation of some results was impossible due to the spontaneous decomposition of the malonic acid. As no information is available in the literature about decomposition rates of malonic acid in sulfuric acid at the concentrations used, it was …

A Study Of Molecular Diffusion In Polymer Solutions By A Microinterferometric Method, Girish T. Dalal

Masters Theses

"A microinterferometric method was used to study the effect of solute concentration on the diffusion coefficient in polymer solutions and also to determine the effect of polymer concentration on the diffusion coefficient. The polyacrylonitrile-dimethylformamide system was used as a means of determining the accuracy of the experimental apparatus and procedure. The non-ionic, water soluble polymer, hydroxyethyl cellulose (commercially known as Natrosol), was used to study this effect with urea and D-glucose as the solutes.

The results obtained for the polyacrylonitrile-dimethylformamide system were in close agreement with the results obtained by Secor, which meant that the experimental technique is accurate enough …

The Anodic Oxidation Of Maleic Acid, Larry D. Gilmartin

Masters Theses

"The purpose of this investigation was to determine the mechanism of the anodic oxidation of maleic acid on platinized-platinum electrodes at 80⁰C. Current density-potential studies were conducted varying the parameters of maleic acid concentration and pH. The faradaic efficiency of the oxidation of maleic acid to yield CO₂ was determined. The effect of temperature on current density was also studied to determine the activation energy for the reaction. The oxidation of maleic acid occurred only in acidic solutions. The faradaic efficiency was found to be approximately 97 ± 5 per cent. A linear Tafel region was found which had a …

The Anodic Dissolution Of Magnesium In Aqueous Solutions, Chen-I Lu

Masters Theses

"The anodic dissolution of magnesium was studied in MgCl₂-KC1 and MgBr₂-KBr mixtures at 25, 40, and 55 °C. The parameters of the study were current density, concentration of magnesium ion, and temperature. The concentration of magnesium ions was varied from 0.001 to 1 N holding the ionic strength constant at 1.5. The weight loss of magnesium from the electrode during electrolysis was determined by weighing the electrode both before and after electrolysis. The current was measured with a sensitive milliammeter. The range of the current densities was varied from 0.001 to 0.1 amps·cm^-2. The …

A Study Of The Removal Of Alkyl Benzene Sulfonate By Means Of A Column Packed With Sand Coated With Ferric Oxide, Chang I. Fung

Masters Theses

"Iron, precipitated in the form of hydroxides on sand particles (-48 + 65 mesh) and stabilized by drying at 100°C for 10 hours, was utilized to remove alkyl benzene sulfonate (ABS) from aqueous solutions. Solutions containing a maximum of 5 mg/l ABS were passed through a glass column packed with treated sand. The ABS formed a complex with the iron precipitants which adhered to the sand particles.

Preliminary work, in which solutions containing 10 mg/l ABS were treated with various concentrations of FeCl₂ at the equivalence point (pH about 9.5), verified the fact that ABS could be removed by …

A Crystallographic Study Of The Pbzro₃-Pbtio₃-Bifeo₃ Ternary System., Dannie R. Clarida

Masters Theses

"The purpose of this investigation was to conduct a crystallographic study of the PbZrO₃-PbTiO₃-BiFeO₃ ternary system, where all three components are perovskites. Lead zirconate is antiferroelectric, lead titanate is ferroelectric, and bismuth ferrate is thought to be ferroelectric. X-ray diffraction analysis was employed to determine the crystallographic structure and lattice parameters.

A tetragonal region was found to exist in the area of high PbTiO₃ content. A rhombohedral region occurred in the remainder of the system with high BiFeO₃ and PbZrO₃ content, except for an orthorhombic envelope along the PbZrO₃-BiFeO₃ side of the diagram up to approximately 70 per cent BiFeO₃.The …

Further Studies Of The Catalytic Oxidation Of Ortho-Xylene To Phthalic Anhydride Using A Fluidized Bed Reactor., Richard Shih-Chun Chu

Masters Theses

"This investigation was conducted to further study the vapor-phase oxidation or o-xylene to phthalic anhydride in a fluidized bed catalytic reactor. Parameters investigated during the study were temperature, catalyst volume, and catalyst activated by use or different promoters. Two different vanadium pentoxide catalysts were used. One was a new catalyst(Catalyst I) supported on a silica base and diluted with potassium sulfate. The other catalyst(Catalyst II) was similar to the first one except that it had been used in a commercial fixed bed reactor operated by the Monsanto Company, St. Louis, Missouri, using naphthalene as a reed material. It had been …

Anodic Dissolution Of Silver In Aqueous Solutions, B. W. Jong

Masters Theses

"The purpose of this investigation was to study the anodic dissolution of silver in various electrolytes to determine if there existed any deviations from Faraday’s law in nitric acid-silver nitrate solutions. The effect of small additions (10^-4 and 10^-5 N) of Cl^-, SO₄⁼, and CrO₄⁼ on the apparent valence and dissolution potential was also studied. Current densities were varied from 0.00 to 0.07 amp·cm^-2.

Based on the observed apparent valences and a grey film containing metallic particles on the anode surface, it was concluded that deviations from Faraday’s law …