Chemical Engineering Commons^™

Reaction Of Hydrogen With Methylene Chloride And Carbon Tetrachloride At High Temperature, Hun Tsao

Theses

The reactions of methylene chloride and carbon tetrachloride in hydrogen in the temperature range 500 - 1000° C were studied using tubular flow reactors of three diameters. (ID: 0.40, 1.05, 1.60 cm). Residence time range was from 0.3 to 3.5 seconds. Temperature profiles of the reactors was kept within +/- 5° C of central 85% for the 18 inch long reactor, at a total pressure of 1 atmosphere. No chlorinated hydrocarbon products were observed at or above 950° C. The major products in this temperature range were CH4, C2H₂, C2H₄, C2H₆ and HCl.

The pseudo …

A Study Of The Dynamics Of Microbial Competition For A Single Resource In A Chemostat Between Reversible Attachment To Solid Surfaces, Pericles Theofilos Lagonikos

Theses

It is known that two microbial populations competing for a single non-renewable resource in a homogeneous environment with time-invariant inputs cannot coexist in a steady state. The case where two microbial populations exhibiting reversible attachment to the walls of a chemostat compete for a single resource is studied theoretically. Because of the cell's attachment to the walls, the environment is no longer homogeneous. The present study considers the case where the attached cells form no more than a monolayer. The Baltzis-Fredrickson model is used to represent the attachment to the walls. In one system the attachment of cells of the …

A Mathematical Model Of Photopolymerization In A Batch Reactor, Jyh-Yao Li

Theses

A mathematical model of a photo initiated additionpolymerization in a batch reactor was developed.

The model considered initiation, propagation and, termination to simulate the addition polymerization process, The model has the advantage that the concentration of any particular n-mer may be calculated without calculating all of its precursors. Other methods do not have this property. An analytical solution to the model for the photopolymerization of styrene was solved. The calculations were run on a VAX 8800 computer and the results were then compared with the experimental results. The calculated results fitted the experimental results to some extent. Effects from the …

Studies Directed Toward Beta-Cyclodextrin And Capped Beta-Cyclodextrin Mimics Of Alpha-Chymotrypsin, Preston Marlon Canzius

Theses

Molecular mechanics calculations were used to investigate beta-cyclodextrin and capped beta-cyclodextrin as models for the active site of alpha-chymotrypsin. The Amber molecular mechanics force field was used to investigate the effect that addition of the caps has on the conformation of the beta-cyclodextrin macrocycle.

The RMS module of Amber was used to calculate differences in position between the atoms of the minimized mimics and those of the X-ray crystal structure. The deviation in position of the atoms of the minimized capped beta-cyclodextrin macrocycle was found to be larger than that of the minimized beta-cyclodextrin, indicating that the caps do affect …

Theoretical Studies Of A Norbornane Mimic Of Acyl-Alpha-Chymotrypsin, Pin-Nan Chen

Theses

Molecular mechanics calculations were used to investigate the structural flexibility of the norbornane mimic which is a model of an acyl-alpha-chymotrypsin intermediate. The Amber molecular mechanics force field was used to perform the conformational analysis.

Comparison of the optimized conformations of different energy has shown the relative structural rigidity of this molecule. Structural superposition of the minimized mimic to the native conformation of chymotrypsin shows that the mimic has a very similar spatial arrangement of its functional groups compared to the catalytic triad of the real enzyme.

Molecular electrostatic potential maps calculated in planes parallel to the average plane containing …

Hydrodechlorination Reactions On Silica-Supported Rhodium Catalysts, Yung-Ming Chen

Theses

The objectives of this study were to investigate the pathways of the hydrodechlorination reactions over silica-supported Rh catalysts as well as identify selectivities and deactivation properties.

Reaction of 1,2-dichloroethane with hydrogen over Rh/SiO₂ catalyst was studied in the temperature range 200 to 300°C. Formation of two intermediates was proposed while 1,2-dichloroethane was adsorbed on the catalyst, the reactive intermediates then produce ethane, ethylene, chloroethane and methane. From the methane formation, it was inferred that the ethane hydrogenolysis occured over the Rh/SiO₂ catalysts. Higher conversion to C₁ and C₂ hydrocarbons was observed at higher reaction temperature. The …

Separation Of Chromium From Waste Sludges By An Electric Membrane Process, Freeman Nai-Tchun Ho

Theses

The process is characterized by using metallic membrane as a filter which is charged by a separate DC-power supply and it may become experimentally very effective in increasing the separation potency and migration flux. The technique of integrating migration with electromembrane was evaluated for the removal of chromium. The transport was found to be adequately described by an equation in which the rate is proportional to the chromium concentration. The rate of dichromate ions transported across the membranes and the gel water content of membrane increased when the ratio of electromembrane potential and cell system potential was increased. The back …

Particle Size Distribution In Isothermal Batch Emulsion Polymerization, Bhavin R. Patel

Theses

A detailed modified mathematical model for particle size distribution in isothermal batch emulsion polymerization of Styrene and Vinyl acetate is proposed on the basis of the population balance approach in presence of several kinetic and mass transfer processes. This study is limited to Smith-Ewart's case II, which assumes instantaneous free radical termination within the polymer particles. Radical desor¬ption mechanism from polymer particles is included in the model and the desorption rate is formulated from the diffu¬sion theory which suggests that the rate co-efficient should be inversely proportional to the surface area of polymer particles.

Experimental runs are made using laser …

The Effect Of Inorganic Salts On Adsorption Of Organics By Fly Ash, Pai-Yuan Horng

Theses

Optimum amounts of inorganic salts ( monovalent, divalent, and trivalent chlorides ) added to various bituminous coal fly ashes in batch adsorption treatment experiments indicates the possibility of improving adsorption capacity.

Experiments were conducted on aqueous solutions of three priority pollutants : phenol, toluene, benzene. Both high fusion and low fusion fly ashes were used as sorbent materials. Removal of organic pollutants was measured using a total organic carbon analyzer.

Isotherm tests positively indicate that the addition of inorganic salts to fly ash significantly increases adsorption capacity. The study shows that removal of organic pollutants by fly ash depends on …

The Kinetics And Mechanism Studies Of Cathodic Electro-Initiated Crosslinking Polymerization Of Unsaturated Polyester Prepolymer, Joseph Yuan-Ji Sheng

Theses

The cathodic electro-initiated polymerization reaction of the unsaturated polyester prepolymer has been found to have the characteristics of the first order ionic initiation polymerization mechanism. The rate of polymer formation is directly proportional to the current intensity and voltage supplied, but inversely proportional to the reaction temperature. The rate of initiation can be expressed as a function of the initial concentration of the prepolymer, residence time and reaction temperature. The rate expression of the initiation step has been derived based upon the experimental data collected as follows:

ln W = k0 exp[-Ea/RT] Ca0 ln t + ln b

where k0 …

High Temperature Reactions Of Chloroform With Methane, Thomas Siozopoulos

Theses

The reactions of Chloroform with Methane were studied at atmospheric pressure in the temperature range of 550-800 deg C, and using three different reactor diameters.

The reaction was found to follow pseudo-first order kinetics in the presence of excess Methane and Argon, and the kinetic parameters were determined for each of the reactor sizes.

The resulting global Arrhenius expressions are:

For 0.4 cm ID Kexp = 2.03 * 10⁸ exp (-34000/RT)

For 1.05 cm ID Kexp = 9.86 * 10⁸ exp (-37950/RT)

For 1.6 cm ID Kexp = 4.17 * 10⁸ exp (-36760/RT)

An increase in the …

A New Density-Dependent Mixing Rule For Equations Of State, Theodore John Shatynski

Theses

A general procedure for the development of density-dependent mixing rules is demonstrated. This method is used to obtain a density-dependent local-composition mixing rule based on an extention of the work of Knox et al (1984). The resulting expression is tested with the Soave-Redlich-Kwong equation of state. Results for normal and cryogenic vapor-liquid systems for both one-parameter and three-parameter versions of the mixing rule are compared with results using the classical mixing rules.

The Biochemical Fuel Cell : Conversion Of Waste To Energy, Charles August Mielke

Theses

A batch biochemical-fuel cell was constructed and studies on the production of bioelectric energy using an alga Scenesdesmus quadricauda, and a bacterium Desulfovibrio desulfuricans, were conducted. Results were compared for a steady state cell using various concentrations of media components and showed that a 1000-fold increase in the concentration of media components produced a net potential output of 0.03mv/ml compared to an initial output of 0.02mv/ml. Further studies showed the biochemical net potential output using activated sludge from a waste treatment facility was 0.01mv/ml compared to 0.02mv/ml for the cell using the initial media concentration.

The system exhibited steady state …

Gas-Phase Reaction Of 1,2-Dichloroethane With Hydrogen In A Tubular Flow Reactor, Wei-Lian Lee

Theses

We have studied the reaction of 1,2-dichloroethane with H₂ in three tubular flow reactors of different diameters at atmospheric pressure in the temperature range of 550° C to 1000°C. The kinetic parameters and product distribution were experimentally determined for each size reactor. The wall and bulk reaction rate constants were decoupled via analysis of three different surface to volume reaction data.

The experimental reactor was an isothermal tubular flow reactor that operated within the domain of plug flow region. The reaction was found to follow first-order kinetics with respect to 1,2-dichloroethane when in the presence of excess hydrogen. The …

Thermal Decomposition Of Chlorobenzene In An Atmosphere Of Hydrogen, Edward Robert Ritter

Theses

The thermal decomposition of chlozobenzene was investigated in a tubular flow reactor at 1 atmosphere total pressure and average residence times of 0.02 - 2.5 seconds. The temperature range from 800 - 1010°C was studied in both a reductive atmosphere of hydrogen and an inert atmosphere of heIium. Complete destruction of chlorobenzene occurs at about 1000°C for an average residence time of 1 second in hydrogen gas. In the inert gas, the complete destruction of the reagent was not observed in the range of conditions which were studied. The major products observed for pyrolysis in hydrogen were benzene, HCl, and …

Zeta Potential Measurements Of Biological Flocs Using A Streaming Potential Cell, Wayne James Gallagher

Theses

A streaming potential apparatus was assembled and tested. Its purpose was to characterize the surface of biological flocs in a wastewater environment. Samples of mixed liquor were obtained from the Passaic Valley Sewerage Commissioners wastewater treatment plant in Newark, New Jersey. Filtered mixed liquor was passed through a bed of the floc particles in the streaming potential cell, and the electric potential across the cell was measured as a function of the differential pressure drop. From these data, the zeta potential was calculated using the Helmholtz equation. Values of -0.88 and -0.44 millivolts were obtained for two mixed liquor samples.

A Theoretical Study Of Pure And Simple Competition Between Two Microbial Species In Configurations Of Two Interconnected Chemostat, Cheng-Ming Kung

Theses

It is known that two microbial populations competing purely and simply for a common substrate cannot coexist in a steady state in an environment which is spatially homogeneous. Hence they cannot coexist in a chemostat something which implies that a mixed culture of two pure and simple competitors cannot be maintained in a single ideal reactor in a steady state. The present study investigates theoretically pure and simple competition between two populations in two interconnected chemostats. Three reactor configurations are considered and analyzed. It is proved that two pure and simple competitors can coexist in a steady state in both …

Preparation And Kinetic Study Of Immobilized Enzyme Catalyst, Sanjiv S. Kuray

Theses

Degradation of commercially available immobilized Glucose Isomerase enzyme was studied in a batch reactor. Effect of shearing on the degradation was studied by comparing the performance of a basket type reactor ( with enzyme kept inside the stirrer) and ordinary batch reactor ( with enzyme kept outside the stirrer).

Invertase enzyme is available commercially in a free soluble form. It was coupled with a new kind of starch derivative. The coupling efficiency achieved was 8.7 % and the concentration of the immobilized enzyme was 718 U invertase per gram of starch. The deactivation of enzyme-starch gel was studied in a …

Dispersion In The Laminar Flow Of Ellis Model Fluids Through Straight Tubes, Yeong-Hua Huang

Theses

Taylor-Aris dispersion theory is extended to the laminar tube flow of Carreau model fluids and Ellis model fluids and the results are compared with those of power law fluids. It is found that Carreau and Ellis models are more appropriate than power-law model, especially at low pressure gradient.

An exact solution to the unsteady convective diffusion equation in fully developed laminar flow in tube is obtained by applying the generalized dispersion theory of Gill and Sankarasubramanian for Ellis model. The results are compared with those obtained by Booras and Krantz for power-law model. The most interesting result of this work …

The Effects Of Platelet Activating Factor (Paf) On The Arteriolar Average Blood Velocity And Volumetric Flowrate In The Microcirculation Of The Hamster Cheek Pouch, Patricia Ann Shatynski

Theses

The effects of platelet activating factor (PAF) in vessel diameter, average red blood cell (RBC) velocity and volumetric flowrate were studied in twenty-four arterioles located in the cheek pouches of nine male syrian golden hamsters. The observed vessels were between 8-32um in diameter. These vesgs were subdivided further into two groups: 8-17um and the 21-32um group. Fluorescein isothiocyanate (FITC) labeled cells were injected into the hamster to act as velocity tracers. Immediately prior to and for a total of 60 minutes after the topical application of 10^-7M and 10^-9M PAF, selected arterioles were video taped periodically …

An Analysis Of Carrier Facilitated Transport In Liquid Surfactant Membranes, Pei-Jen Tsai

Theses

Mathematical models describing the mass transfer through facilitated liquid membranes are proposed and solved analytically. A self-adjoint operator method is applied to solve the coupled differential equations with discontinuity in the boundary conditions. It is assumed that equilibrium of the solute at the interfaces is maintained during the separation process. The effects of film resistance are studied/ and a first order kinetic model is used to simulate the reaction which takes place at the membrane-internal phase interface.

Experimental results indicate that the model with external film resistance consideration is in good agreement with the experimental data. This shows that most …

Preparation And Properties Of Monomers Derived From Hydroxyhexyl Methacrylate For Dental Adfesive, Ren-Dar Ku

Theses

Although methacrylic acid is the simplest unsaturated carboxylic acid and its hydroxyl ester polymerize readily, yielding useful resins, no adequate study of the preparation and application of the higher hydroxyl alkyl methacrylates has been published. The commercially important hydroxyethyl and hydroxypropyl methacrylates are manufactured from the appropriate alcohol in the presence of sulfuric acid, a method which appears to be less suitable for production of higher hydroxyl alkyl methacrylates. The purpose of the present work was to prepare the hydroxyhexyl methacrylate (HHMA) by a generally applicable method and determine its common physical properties. In addition, the urethane methacrylates were synthesized …

Computer Aided Mathematical Modeling Of A Once Through Claus Type Sulfur Recovery Process, Yuriy Osyp Kutny

Theses

The computer aided mathematical modeling of the once through Claus process for hydrogen sulfide conversion to sulfur is presented herein. This vapor phase oxidation reaction is carried out using one thermal reactor and up to three bauxite catalytic reactors with sulfur condensers in between. The method of catalytic reactor feed reheat and its ramifications upon reactor performance and total model convergence is of major importance.

The reactor feed preheat can be carried out in either of the following ways: (1) indirect heat exchange using some external heat source; (2) indirect heat exchange using other hot process streams as heat source; …

Osmotic And Mean Activity Coefficients Of Cacl2, Nai, Libr And Licl In Ethanol At 50 Degrees C, Gregory J. Czerwienski

Theses

Vapor pressure depression data for CaCl₂, NaI, LiBr, and LiCl were measured at a molality ranging between 0.2-7.5 depending on the solubility of the salt in ethanol. Data were also measured at 35° C for the LiCl. The apparatus used was a recirculation still of the Othmer type.

Osmotic coefficients were calculated from the total pressure of the system. The one parameter Bromley equation and the three parameter Pitzer equation were used to correlate the data. For all the systems, the Pitzer equation correlated the data better as one would expect. Mean activity coefficients were calculated graphically and …

The Separation Of Proteins Via Charged Electromembrane Process, Chi-Wen Lin

Theses

A new method for separation and concentration of protein and other biocolloids such as hemoglobin and albumin was developed by a process called the charged electromembrane (CEM) process. The process is characterized by using a metallic membrane as a filter which can carry either positive or negative electric current.

The effect of various factors on the separation coefficient and filtration efficiency were investigated experimentally. These factors include strength of electric field, pH of colloidal solution, electric current through membrane filter and flow rate.

It was found out that the thickness of the gel layer formed on the membrane could be …

The Kinetics And Mechanism Studies Of A Polymer Powder Coating On Metal Surface By Cathodic Electrodeposition Process, Wen-Lin Wu

Theses

A polymer dispersion of fluorocarbon with solid constent in the range of 10-25% were prepared from white powder polytetrafluorethylene (PTFE), emulsifier combination of dodecylbenzyldimetlyl sulfonium chloride and Trition N-150, and other components or additives. Such a fluorocarbon dispersion is very stable against coagulation and has a pH in the range of 8-10, which is especially suitable for powder coating purpose.

A new electrocoating technique, which is called cathodic electrodeposition powder coating method, was conducted in this study. This new coating method includes four steps: pretreatment, electrocoating, drying and baking. Two kinds of degreased metal substrates, aluminum and steel plates, were …

Prediction Of Vapor And Liquid Equilibrium Properties For 25 Organic Priority Pollutants In Aqueous Solution, Pinchieh Pai

Theses

Activity coefficients and Henry's law constants for 25 organic priority pollutants were estimated using UNIFAC thermodynamic calculations. For 6 of these compounds, the results were compared with measured values reported in the literature. This indicated errors in the UNIFAC predictions varying from 24.0% to 95.0%. Best results with UNIFAC were obtained using liquid-liquid equilibria, rather than vapor-liquid equilibria.

Octanol/water partition coefficients were also estimated for the same 25 organic priority pollutants using the fragment constant method. Results differed from values reported in the literature by 5% to 170%.

Estimated activity coefficients were also used to predict stripping rates of organic …

Biodegradation Of Phenol And 2-Chlorophenol Using A Fill-And-Draw-Reactor, Chi-Chun Tsai

Theses

The biological degradation of phenol and 2-chlorophenol was studied at room temperature in a microprocesser controlled fill-and-draw reactor using activated sludge from the Passaic Valley Sewerage Commissioners wastewater treatment plant (Newark, New Jersey). The reactor was cycled through four unit processes: fill, react, settle, and draw. Different cycle times were tested, and the system response was characterized by dissolved oxygen measurements and substrate analysis (by gas chromatography).

With inhibitory substrates, such as those tested, this reactor had much more flexibility, and was therefore much easier to operate, than a standard continuous flow reactor.

The Conversion Of The Process Flowsheet Simulator, Flowtran, For Fortran 66 Based Mainframe Computers, Timothy Edward Roche

Theses

The process flowsheet simulator FLOWTRAN was converted from FORTRAN 77 code to FORTRAN 66 code. The conversion was accomplished by developing a number of subprograms to handle FORTRAN 77 intrinsic functions that are missing in the FORTRAN 66 standard and by altering the code to take advantage of the developed subprograms. Also developed were a set of procedure files for executing the FORTRAN 66 FLOWTRAN on a Sperry-Univac 90/80-4. The new FLOWTRAN was tested and performs identically to the FORTRAN 77 version. The FORTRAN 66 FLOWTRAN can be installed on any mainframe computer with a FORTRAN 66 compiler.

Electrochemical Reduction Of Quaternary Ammonium Salts, Rudolph K. Kapichak

Theses

The electrochemical reduction of two highly hindered quaternary ammonium salts was attempted. The reductions were performed in hexamethylphosphoramide at a controlled potential using platinum electrodes. It was anticipated that these reductions would provide a route to the formation of anti-Bredt bridgehead olefins. This work is an extension of the work of Dubois, Monvernay and Lacaze who electrochemically reduced quaternary ammonium salts such as trimethyl-t-butylammonium iodide (XX).

Trimethy1-2,4,4-trimethy1-2-pentylammonium iodide (XXIII) was reduced to form 2,4,4-trimethyl-l-pentene (XXVI) and 2,2,4-trimethylpentane (XXV). The yields of the two runs of this reduction were 10% and 20% and in the first run of the reduction 75% …