Engineering Commons^™

A Dynamic Model Of Fill-And-Draw Reactor Utilizing An Inhibitory Substrate, Yun-Fei Ko

Theses

A dynamic model of a fill-and-draw reactor has been developed, which includes a number of operational parameters, the fraction of total cycle time devoted to fill, reaction and draw, and the concentration of the toxic substance in the feed to the reactor.

Operating diagrams have been generated, from which one can choose suitable operating parameters.

The model has been solved numerically for Andrews kinetics ( substrate inhibition ), and tested experimentally, using a 5-liter fill-and-draw reactor with phenol as sole carbon source and a pure culture of Pseudomonas putida. Results compared very well to the model predictions.

Gas-Phase Reactions Of Methylene Chloride And Methylene Chloride-Trichloroethylene Mixture With Methane In Tubular Flow Reactor And Atmospheric Pressure, Javad Tavakoli-Attar

Dissertations

Reactions of methylene chloride diluted in methane and Argon and a mixture of methylene chloride + trichloroethylene diluted in methane and argon are studied in three flow reactors of different surface to volume ratios 4, 10.5, and 16 mm ID , atmospheric pressure and over a temperature range of 750-1000 °C. Experiments were conducted isothermally, ±5 °C over central 80% of oven length using a three zone oven. Argon was added as a diluent in order to limit carbon (s) formation. The concentration ratios of methylene chloride/methane/argon and methylene chloride/trichloroethylene/methane/argon was held constant at 1:4:10 and 1:1:40:40 respectively, throughout the …

Formation Of Light Hydrocarbons And Soot In The Pyrolysis Reactions Of Chloro, Dichlorobenzene, Acetylene And Benzene In An Atmosphere Of Hydrogen, Larry Jiyuan Zhu

Theses

The kinetics of thermal decomposition of chlorobenzene and dichlorobenzene in a hydrogen and helium atmosphere were further studied to investigate formation of soot and light hydrocarbons. The experiments were performed at atmosphere pressure with residence times rangeing from 0.2 to 1.2 seconds, and the temperature ranges of 850°C to 925°C for chlorobenzene and 870°C to 910°C for dichlorobenzene. Flame ionization detectors, which were connected to GC columns, were utilized for the qualitative and quantitative analysis of the reaction products. A methyl silicone capillary column was used analyzing of heavy aromatics and a Carbosive G was used to analyze light hydrocarbons. …

High-Energy, Curable Polycyclopentadiene Binder For Solid Rocket Propellants, Jian Guo Ning

Theses

Diels Alder polymerization of cyclopentadiene ( CPD ) has been carried out at 170°C under inert atmosphere. The resulted polymer has a low bulk viscosity, 7.4 cps, and a number average molecular weight M_n up to 3000. This liquid Prepolymer is curable with maleic anhydride. With ammonium perchlorate, aluminum, and maleic anhydride, a high energy solid propellant has been formulated with this polymer. Via bomb calorimeter, Instron, and density measurement, it was found that this propellant has a better heat of combustion, tensile strength, and solid loading than that of the commercial rocket propellant based on hydroxyl terminated polybutadiene.

A Study On The Poly(Ethylene Terephthalate)/Flouropolymer Blends, Chyan-Nin Chiu

Theses

The rate of crystallization of Polyethylene terephthalate) (PET) can be improved by blending it with polyethylene co chlorotrifluoroethylene) (ECTFE; tradename Halar) so that it can be suitable for injection molding. The special advantage of this method is that molecular weight of the blend will not decrease so much as by adding nucleating agents. That is to say, the mechanical strength of the blend will not decrease very much compared with that of virgin PET.

Reactor Design For Hazardous Waste Treatment Using A White Rot Fungus, Daewon Pak

Dissertations

Various nutrient media and reactor configurations have been explored in order to grow the white rot fungus Phanerochaete chrysosporium, induce its active enzyme, develop kinetic data for the degradation of 2-chlorophenol, and use chemical engineering analysis to design an efficient reactor.

Preliminary experiments indicated that the biodegradation rate was improved by two to three orders of magnitude when the fungus was immobilized. As a result, emphasis shifted to two types of reactor design: a packed-bed reactor employing a silica-based porous support, and a fluidized-bed reactor employing alginate beads. Both were very effective in degrading 2 chlorophenol at inlet concentrations up …

Use Of Recirculation Reactor To Study Biodegradation Of 2-Chlorophenol, Kai-Chung Yang

Theses

The performance of immobilized cells in the treatment of hazardous waste was investigated using a recirculation flow reactor run in a batch mode. A mixed microbial population from a municipal wastewater treatment plant was immobilized in calcium alginate gel. The bio-oxidation ability of these microbes towards a model toxin (2-chlorophenol) was studied. The process parameters studied were as follows:

1. Flow rate of the recycle stream;
2. Biomass loading;
3. Spiking concentration of 2-chlorophenol;
4. Use of buffered vs. non-buffered defined medium.

Dissolved oxygen concentration was monitored using a flow Clark-type dissolved oxygen probe. Oxygen consumption was correlated with the biodegradation of 2-chlorophenol. Physical …

Synergistic Fillers In Polymer Concrete : New Composites, Syed Hassan Javed

Theses

The objective of this study was to examine the effects of synergistic fillers on underwater construction, burning and mechanical properties of polymer portland cement concrete(PPCC).

Fine grains of hydrous calcium sulfate, Trihydrated alumina, Calcium carbonate and fibrous unhydrous calcium sulfate were examined in PPCC. It has been observed that these synergistic filler improves the mechanical property (stress) and reduce the average time of burning of PPCC. With fixed quantity of polymer, the deterioration of PPCC in water increases by replacing the sand with above stated fillers.

Wastewater Treatment : Phenol Extraction By Liquid Membrane, Jan-Ming Hou

Theses

Two models for the extraction of phenol by means of liquid surfactant membranes is presented in which external mass transfer around w/o emulsion drop, phase and chemical equilibria are taken into account.

The nonlinear coupled P.D.E.'s is solved under assumptions to get a close-formed analytical approximate solution. The experimental results on the batch extraction of phenol are found to be satisfactory simulated by one of the proposed models provided that phenol concentration is higher than 0.01N. The model requires no adjustable parameter thus it can predict the extraction behavior without doing experiments.

Determination Of Polycyclic Aromatic Hydrocarbons From Incineration Emission Samples, Robert Cebula

Theses

Stack emissions from five sources (one pulverized coal combustion operation, three sewage sludge incineration operations and one gray tin refractory operation) were sampled by use of U.S. EPA Modified Method 5 isokinetic sampling unit for vapor and particulate effluent. The sampling unit provided XAD-2 resin samples, polytetrafluoroethylene and glass fiber filters and impinger washings of dichloromethane. The resins were soxhlet extracted using dichloromethane (DCM) and the filters were soxhlet extracted using DCM followed by acetone. Fractionation of extracts was accomplished by thin layer chromatography. The resulting fractions were analyzed for polycyclic aromatic hydrocarbons (PAH), nitro-PAH and quinone-PAH by high-performance liquid …

Bead Design For Biodegradation Of 2-Chlorophenol Using Microorganisms Entrapped In Alginate Gel, Fayaz Lakhwala

Theses

The performance of immobilized cell reactors varies with a number of parameters, one of which is proper bead design. A mixed microbial population from a waste water treatment plant was immobilized in calcium alginate gel. The viability of these organisms was studied in a microassay reactor by varying parameters such as concentration of calcium chloride, concentration of sodium alginate, temperature of operation, biomass concentration within the beads and concentration of a model compound (2-chlorophenol). The effect of storage on viability over a period of three months was also investigated. It was found possible to have access to active biomass by …

Recycled Plastics As Fillers In Polymer Cement Concrete Composites, Shian-Jong Liu

Theses

How to handle the plastic waste is a big task for the modern society in environmental protection. People already focus on it, especially in PET soft drink bottles. Although PET bottle can be reclaimed, its usages are restricted due to the limitation in color and difficulty in purification.

On the other side, concrete is the most common material for human beings to used [sic] in construction. Concrete has good compressive strength, but poor [sic] in flexural and tensile strengths, which limits its applications. So, scientists try to improve its properties by adding the polymer into the conventional concrete, to enhance …

Biosynthesis Of Amine Oxides Using Calcium-Alginate Immobilized Hog Liver Microsomes : An Evaluation Of Process And Reactor Design, Ioannis I. Valvis

Theses

An evaluation of the biocatalytic ability and the potential utilization of Calcium-alginate immobilized hepatic microsomes (beads) for the biosynthesis of amine oxides has been performed, To accomplish this task, the following three areas Were investigated: immobilization, catalytic biooxidation ability, and reactor configurations.

Immobilization was found to result in higher yields over free microsomes at the expense of higher cofactor requirements. Refrigerated drying of immobilized micro-somes appears to be a better storage technique than wet storage in buffer. Smaller beads resulted in higher rates than larger beads, but size did not affect the overall yield.

Chlorpromazine (CPZ), diphenylamine (DPA) and 4-hydroxy-2,2,6,6-tetramethylpiperidine …

A Dynamic Model Of A Fill-And-Draw Reactor And Its Implications For Hazardous Waste Treatment, Shing-Hwa Chang

Theses

A dynamic model of a fill-and-draw reactor has been developed, which includes a number of operational parameters such as the draw-down volume, the fraction of total cycle time devoted to fill, reaction, and draw, and the concentration of the toxic substance in the feed to the reactor. The model has been solved numerically for two cases, one assuming Monod kinetics, and one considering substrate inhibition (Andrews kinetics).

The conversions achieved with this type of reactor have been compared to that of a conventional activated sludge (CSTR) design. These results indicate that for most practical settings of the operating parameters, the …

Programming For The Prediction Of Thermodynamic Phenomena, One Kwon Rim

Theses

A Thermodynamic Calculation Program was developed. The program contains the calculation procedure for VAPOR/LIQUID EQUILIBRIUM(Isothermal P-X data and T-X data), HEAT-OF-MIXING(liquid mixture data) and LIQUID/LIQUID EQUILIBRIUM SEPARATION data. The program may optionally use the Knox Molecular(GAM), UNIQUAC, NRTL, Wilson and Redlich-Kister equations, and is prepared to accept any kind of model which will be developed in the future. This program also performs parameter file creation, parameter input, updating of parameters, and is structured to allow implementation of data regression when program is updated. Comparison and analysis of each function were executed using this program. It was revealed that VLE(Vapor-Liquid Equilibrium) …

Synthesis And Characterization Of A Novel Blocked Isocyanate Dental Adhesive Based On Diphenylmethane - 4, 4' - Diisocyanate, Yangming Lin

Theses

The dental adhesive monomers based on diphenylmethane - 4,4 - diisocyanate (MDI) were prepared and studied in this research. The diisocyanate, MDI, was first reacted with hydroxyethyl methacrylate (HEMA) to form an intermediate adduct. This adduct had an active isocyanate end group. It was then bonded with o-chlorophenol (OCP), a blocking agent, to produce a blocked isocyanate monomer.

The new blocked isocyanate (HEMA-MDI-OCP) was found to have an average value of more than 1200 psi in tensile tests measuring its adhesion to dentin slices.

Hydrodechlorination Reactions Of Trichloroethylene And 1,1 1, Trichloroethane Over Alumina Supported Palladium Catalysts, And, Trichloroethylene Over Nickel Catalyst, Atul R. Shah

Theses

The primary objective of this study was to evaluate the viability for conversion of chlorocarbon wastes solvents into useful hydrocarbons and HCl by catalytic reduction. The second objective was to investigate the pathways for these hydrodechlorination reactions over the chosen alumina supported Palladium and nickel catalysts as well as determine selectivities, product distribution, and deactivation mechanism.

Reactions of trichloroethylene with hydrogen over alumina supported palladium catalyst was studied in temperature range 40°C to 57°C at one atmosphere total pressure. The major products observed were ethane and (cis) 1,2 dichloroethylene with trace products chloroethylene, chloroethane and (trans) 1,2 dichloroethylene. At the …