Chemical Engineering Commons^™

Aqueous Absorption Of Nitrogen Oxides Induced By Oxychlorine Compounds : A Process Development Study For Flue Gas Treatment, Chen-Lu Yang

Dissertations

The use of chlorine (Cl₂), sodium hypochlorite (NaClO), and sodium chlorite (NaClO₂) as oxidizing agents to promote the absorption of nitric oxide (NO) from gas streams has been investigated in the Gas Scrubbing Laboratory of New Jersey Institute of Technology since 1988. The first step of this project had been to screen out the best scrubbing medium for nitric oxide removal from flue gases. The most successful oxidizing agent was found to be sodium chlorite in acidic aqueous solution. The screening results have been accepted for publication in Chemical Engineering Communications. A sodium chlorite containing aqueous …

Engineering Design Of An Anaerobic-Aerobic System To Treat Chlorophenols, Chih-Ju Jou

Dissertations

The present work was aimed at determining the effect of the main operating parameters on the performance of an anaerobic-aerobic reactor system to degrade toxic chlorinated compounds. In previous work conducted in the Biological Treatment Lab at NJIT it was shown that this system is capable of achieving the complete degradation of chlorophenols. In that system, reductive dehalogenation took place in the first anaerobic reactor, which was followed by a second aerobic reactor in which the degradation products of the first reactor were mineralized. In the present work the role of a number of parameters that can have a significant …

Pyrolysis And Oxidation Of Chloromethanes Experiment And Modeling, Wenpin Ho

Dissertations

An experimental study on pyrolysis and oxidation of CH₂Cl₂ and CH₃Cl in oxygen/hydrogen or oxygen/methane mixtures and argon bath gas was carried out at 1 atmosphere pressure in tubular flow reactors. Degradation of CH₂Cl₂, or CH₃CI, along with the formation and destruction of intermediate and final products was analyzed systematically over 873 to 1273°K, with average residence times of 0.2 to 2.0 seconds.

Thermochemical parameters: enthalpy, entropy, and heat capacities for many chloro-oxy-carbon products and intermediates are calculated using the techniques of group additivity and the THERM computer code. …

Kinetic Study Of Decomposition Of Azo Dyes And Phenol In Advanced Oxidation Processes Reaction Mechanisms, Pathways And Intermediates, Hung-Yee Shu

Dissertations

Advanced Oxidation Processes (AOP) are an emerging technology for treatment of various hazardous organics in wastewater and groundwater. However, the kinetics and mechanisms for AOP have not been well understood. A mechanism including light intensity was studied for the decomposition of azo dyes and phenol in an AOP reactor with a 5,000 watt low pressure mercury lamp. UV light absorption is an important parameter. The effect of pH, hydrogen peroxide dosage, and dye concentration on the decomposition of azo dyes in an H₂O₂/UV reactor were also studied. Reaction pathways and intermediates of phenol oxidation by different …

Competition Between Two Microbial Populations In A Sequencing Fed-Batch Reactor And Its Implications For Waste Treatment Applications, Sitaram Dikshitulu

Dissertations

Pure and simple competition between two microbial populations in a sequencing fed-batch reactor (SFBR) was studied both at the theoretical and experimental level. Competition occurred for a single chemical pollutant which could serve as the sole carbon and energy source for both competitors. A mathematical model describing the process under inhibitory kinetics (as is usually the case with hazardous and toxic substances) was derived and theoretically analyzed. The model predicts that the dynamics of a SFBR, and the kinetics of biodegradation, result in a complex set of operating regimes in which neither species, only one species, or both species survive …

Analysis Of The Optimum Extraction System Design For The Separation And Purification Of Rare Earths, Kenneth Yeon-Kang Chan

Dissertations

A mathematical model for the liquid-liquid equilibrium of the lanthanide and yttrium oxides in the nitric acid - water - tributyl phosphate (HNO₃-H₂O-TBP) two-phase system has been developed. This model is based on the interrelationships of chemical reactions, phase equilibrium, and material balance. The chemical reactions were modelled using experimentally derived empirical equations for components involved. The distribution coefficients of 16 rare earths which were experimentally determined. by UK Harwell Laboratory were used to evaluate the parameters of this equilibrium model. Once model parameters are determined, material balance for all species in the HNO₃-H …

Investigation Of Reactor Design Parameters Towards Optimizing Biodegradation Of Chlorophenols By Phanerochaete Chrysosporium, Nirupam Pal

Dissertations

The biodegradation of 2,4,6-trichlorophenol (246-TCP) and 2,4,5-trichiorophenol (245-TCP) by Phanerochaete chrysosporium was studied in batch and in continuous systems. Contrary to most of the previous reports from the literature, this study shows that degradation of both TCPs can occur in the absence of any measurable ligninase activity. The microorganism did not retain its degradative ability for more than about two weeks

In order to better understand the degradation process, the individual contributions of both the biomass and the extracellular proteins were studied separately. The results show that neither the biomass nor the extracellular proteins alone can completely degrade 246-TCP, but …

A Study On Radical Scavenging And Magnetic Resonance Imaging Characteristics Of Stable Radical Nitroxides, Shiey-Shiun Horng

Dissertations

Several nitroxides have been prepared for study of their image enhancement capability. These nitroxides contain different nitroxyl moieties within one molecule. On MRI examination for the nitroxides prepared, TEMPO and HPTPO are better due to their better water solubility, even though some of the others have more nitroxyl centers available. The intensity response is linear with respect to concentration in the range studied in most of the cases except for HPTPO, whose intensity finally reaches maximum when its concentration is higher than 10 mM.

Three sources of biomass, namely, liver microsomes, whole-cell yeast and a bacterial activated sludge consortium, have …

Kinetic Studies Of Photo-Initiated Oxidation Of Toxic Organic Pollutants Including The Formation And The Destruction Of Intermediates, Yuan-Shen Li

Dissertations

The photo-initiated oxidation process, using hydrogen peroxide or ozone under ultraviolet radiation, has been proven to be an effective treatment method for toxic organic pollutants in wastewater. Most of the recent kinetic studies of the process were concentrated on the breakdown mechanisms of the pollutant itself. The formation and the destruction of intermediates were seldom investigated. Also the mechanisms and their reaction rate constants of free radical formation and destruction in the O₃/UV or H₂O₂/UV reactor were seldom studied.

The objective of this research is to study the kinetics of photo-initiated oxidation of toxic …

Thermal Desorption And Decomposition Of Hazardous Organic Compound I: Mass Transfer Of Benzene And Chlorobenzene In Soil Matrices Ii: Oxidation And Pyrolysis Of 1,1,1-Trichloroethane In Methane/Oxygen/Argon, Yo-Ping Wu

Dissertations

I: Mass Transfer of Benzene and Chlorobenzene in Soil Matrices

Experimental measurements on several apparatus were used in conjunction with chromatographic theory to study the thermal adsorption and desorption of organic vapors on soil with different particle sizes for analysis mass transfer parameters and heat of adsorption. Benzene (C₆H₆) and chlorobenzene (C₆H₅Cl) were tested on soil with 0.55, 0.46, 0.36, and 0.225 mm average particle sizes. Sample injection volumes for organic compounds were studied to ensure linearity of gas chromatography. Equilibrium constants were strongly dependent on temperature but not on particle size. …

Integrated Anaerobic-Aerobic System For The Biodegradation Of Highly Chlorinated Aromatic Compounds, Cheng-Ming Kung

Dissertations

A two-step process was developed for the complete mineralization of hazardous chlorinated aromatic compounds. The system consisted of an anaerobic reactor, in which reductive dehalogenation took place, coupled with an aerobic reactor in which the complete mineralization of the products of the anaerobic dehalogenation occurred.

A mixed anaerobic culture from a municipal sewage treatment plant was enriched and then immobilized on silica-based porous beads to treat 2,4,6-trichlorophenol (TCP), which is the model target compound in this work. In the anaerobic reactor, TCP was degraded to 2,4-dichlorophenol which was, in turn, reduced to 4-chlorophenol (4-CP). Stoichiometric amounts of 4-CP were recovered …

Crystallization Kinetics And Polyblends Of Poly(Ethylene Terephthalate) Recycled From Post-Consumer Beverage Bottles, Peming Peter Hsu

Dissertations

In order to reduce waste generation, and comply with state and federal laws, plastic beverage bottles are usually undergoing recycling. Poly(ethylene terephthalate) [PET], which is the main component the bottles are made of, cannot be used for manufacturing new food containers, and has to be used for manufacturing other end consumer products. The recycled PET is a cheap material, but its use is problematic due to the low crystallization rates of PET. The present study investigates ways of accelerating PET crystallization by using inorganic carbonate salts as nucleating agents. This study also explores the possibility of forming polymer blends based …

Mathematical Modeling Of Mass Transfer In Microvascular Wall And Interstitial Space, Daekyung Kim

Dissertations

The dynamics of macromolecular transport across the microvascular wall and into the adjoining interstitial space was studied in the hamster cheek pouch using intravital fluorescence microscopy in combination with digital image processing. Fluorescein isothiocyanate-labe led dextrans (FITC-Dx) of 70,000 and 150,000 daltons were used as tracers. In each experiment, the time-dependent extravasation of FITC-Dx from a leakage site in a blood vessel was videotaped for about 2 hours. The macromolecular transport from individual microvessels was quantified by digital video-image processing. Histograms of the light intensity distributions for selected fields at various times were obtained and then converted to the interstitial …

Mathematical Modeling Of Chemical Vapor Deposition Processes And Its Application To Thin Film Technology, Norman W. Loney

Dissertations

A number of workers in the field of Chemical vapor deposition (CVD) have presented mathematical models in the literature. Some workers were able to produce analytical expressions for the interwafer concentration profile. These analytical expressions were based entirely on zero or first order chemical reaction rates. Until now, it appears that a chemical reaction rate expression that is not zero or first order directly, must be handled by a numerical scheme.

Presented herein is a mathematical model with an analytical interwafer concentration profile. This concentration profile is neither zero nor first order but shifts from zero to first order as …

Kinetic Studies On Pyrolytic And Oxidative Decomposition Of Chlorocarbons In A Tubular Flow Reactor, Yang Soo Won

Dissertations

Chloroform decay and product distributions were distinctly different in the absence and presence of added O₂ and/or CH₄. Increases in O₂ concentration were observed to speed reagent loss, with a slower decay of chloroform observed for the CHCl₃/CH4/Ar pyrolysis system. In CHCl₃/CH₄/O₂, the major products were C₂Cl4, CH2CCl₂, C₂HCl₃, CO and CO₂ over a wide temperature range. Minor products included CH₂Cl₂, CH₃Cl, and C2H₃Cl. When CH₄ reactant was not present, …

A Combined Gel Entrapped And Membrane Attached Microbial Process For Biodegrading Organic Compounds, Fayaz Saifuddin Lakhwala

Dissertations

A comparative study has been performed between two bioreactors treating phenol, one using calcium alginate entrapped microorganisms, and the other using microorganisms attached on the surface of a polymeric membrane. Laboratory experiments conducted in batch recirculation mode, as well as a continuous feed mode, showed that the calcium alginate bio-bead reactor is more efficient in treating high feed concentrations of phenol, while the membrane bioreactor is more effective in the lower concentration regime (less than 150 ppm). In batch recirculation mode, the reaction rates (expressed as mg phenol/hr*gm dry cells) in the membrane reactor are an order of magnitude higher …

Thermodynamics Of Strong Electrolyte Solutions : Prediction Of Osmotic Coefficients By Pair Correlation Function Method, One Kwon Rim

Dissertations

Thermodynamic properties (osmotic coefficients) of strong electrolyte solutions have been studied by the method of statistical mechanics. First the charged soft sphere potential is developed based on the Pauling type model. Next the charged soft sphere potential is converted to the thermodynamically corresponding charged hard sphere potential by way of the perturbation method developed by Verlet and Weis. Simultaneously, the radial distribution function is developed by modification of the Exponential theory through introduction of the Stillinger-Lovett moment condition. The effective hard sphere diameter values calculated by the perturbation method are combined with the modified Exponential theory, and these quantities are …

Mass Transfer Of Hazardous Organic Compounds In Soil Matrices Relevant To Thermal Desorption/Incineration, Jong-In Dong

Dissertations

Soils contaminated with hazardous organic compounds have been known to threaten human health both directly through various contact mechanisms and indirectly through leaching or transfer to the food chain. Thermal desorption of contaminated soil matrices with secondary treatment of the effluent gases (collection, incineration, etc) is one of most feasible and developing technologies for cleaning of contaminated soils. There is, however, little known about the mass transfer principles of organic contaminants through the heated soil matrices. The objectives of this study is, therefore, to learn and understand details of the mass transfer processes of organic compounds in these soil matrices. …

Protein Separation With Mathematical Modeling For Chromatographic Operation, Hsien-Chih Ma

Dissertations

We have performed experiments and derived mathematical models for packed bed columns used for liquid phase chromatographic separations of proteins with impulse input of feed solutions. These models can now be used to describe the relationships between the elution characteristics (peak height, peak position, and shapes) and the operating conditions (flow rate and buffer conditions) of ion exchange and gel permeation column chromatography for protein separations.

The surface adsorption model was discussed relative to the nature of the mobile and stationary phases in ion exchange column chromatography for two distinct cases: with and without pore diffusion. For large solute molecules, …

Biodegradation Of Benzene And A Btx Mixture Using Immobilized Activated Sludge, Mayur Padamshi Lodaya

Dissertations

Aerobic biodegradation of benzene was studied using activated sludge immobilized in calcium alginate (immobilization by entrapment), and also attached to a silica based catalyst.support (immobilization by attachment). Hydrogen peroxide was used as a source of dissolved oxygen to eliminate physical removal of benzene due to aeration. Abiotic losses of benzene were accounted for.

A recirculation reactor, run in both batch and continuous feed mode, was used to determine the kinetic parameters. The system response was examined by tollowing changes in benzene concentration, flow rate, and biomass loading. The system was modeled mathematically and the kinetic parameters were determined.

Biological removal …

Thermotropic Liquid Crystalline Polyesters Based On The Monomer Of Poly(Ethylene Terephthalate), Satish Baliga

Dissertations

A series of thermotropic liquid crystalline polyesters were synthesized, based on Bis-hydroxyethyl terephthalate (BHET), para-acetoxybenzoic acid (PAB) and terephthalic acid (TA). Structural studies of these aromatic polyesters using Nuclear Magnetic Resonance (NMR), Infrared Spectroscopy (IR) and X-ray diffraction techniques indicated the existence of substantial amounts of rigid -PAB-PAB- linkages within the mesogenic backbone. Optical study of their melts using Polarizing Microscopy indicated a "threaded" microstructure typical of a nematic mesophase. Morphological rearrangements were found to occur at higher temperatures as was evident from a two-phase structure, one phase speculated to be rich in flexible Poly(ethylene Terephthalate) (PET) segments and the …

Kinetic Study On Pyrolysis Of C6h5cl And M-C6h4cl2 Diluted In H2 : Detailed Reaction Kinetics And Thermodynamic Property Estimation Techniques, Edward Robert Ritter

Dissertations

Thermal reaction studies of dilute mixtures (0.37%) of C6H5Cl in hydrogen and m-C6H4C12 (0.4%) in hydrogen have been performed in tubular flow reactors at various surface to volume ratios, and 1 atm total pressure. Residence times range from 0.02 to 2.5 seconds,with temperatures between 1050 to 1275 K. HCl, C₆H₅Cl, C₆H₆, and carbon solids (C(s)) are observed as the major products; minor products include methane, cyclopentadiene, toluene, naphthalene and biphenyls. Pyrolysis in helium yields significantly less conversion, but more C(s) for similar residence times.

A detailed chemical mechanism is developed to describe …

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 …

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 …

Transient Analysis Of Macromolecular Blood-Tissue Exchange In Microvascular Bed, Alex Yefim Bekker

Dissertations

Movement of macromolecules across microvascular walls was studied in the hamster cheek pouch with intravital fluorescence microscopy. A graded series of Fluorescein Isothiocyanate labeled Dextrans(FITC) of 20,000 -70,000 molecular weight were used as representative macromolecular tracers. The time dependent extravasation of FITC-Dextrans was video taped for approximately two and a half hours. Permeation of macromolecules from individual microvessels was quantified by digital video image processing. Histograms of the light intensity distributions for selected fields at various times have been measured and used to construct integral optical density - time profiles of the extravasated fluorochromes for particular leaky sites. An integrated …

The Use Of Pure Cultures As A Means Of Understanding The Performance Of A Mixed Culture In The Biodegradation Of Phenol, Chirasakdi Varuntanya

Dissertations

In an effort to gain a more fundamental understanding of the performance of mixed microbial cultures in the biodegradation of toxic organic chemicals, studies have been conducted using three phenol degrading species isolated from a municipal treatment plant. The rate of phenol degradation was investigated for each of the three pure phenol degrading species, and various combinations of the three species. A simple competitive model was used to predict the behavior of the mixed cultures by using the pure culture Monod rate constants. The model fit the growth data for total biomass very well, although (as with the pure culture …

Fluid Flow And Gas Absorption In An Ejector Venturi Scrubber, Iclal Atay

Dissertations

Empirical models were developed to describe the fluid flow characteristics and gas absorption efficiency of an ejector venturi scrubber. The empirical constants were determined experimentally using stop action photographs of the spray, static pressure measurements, and sulfur dioxide absorption efficiencies.

To take photographs of the spray, a 2 foot high, clear plastic ejector venturi scrubber was used, with a 4 inch diameter gas entrance port. Photographic equipment included a Hasselblad camera, Xenon flash lamp, and Polaroid 667 ASA 3000 film. Exposure duration was about 1 microsecond, resulting in complete stop-action of the spray droplets at liquid rates up to 6 …

Reactions Of Chlorocarbon Species With Hydrogen Over Palladium On Alumina Catalyst And Zeolite Catalyst-Development Of Deactivation Models, Yuh-Der Yang

Dissertations

Four catalytic dechlorination reactions were studied experimentally using a fixed-bed reactor at atmosphere pressure. Reaction mechanisms were proposed, and the kinetics modelled.

The first reaction is 1,2-dichloroethane with hydrogen over zeolite catalyst. Catalyst deactivation models were examined.

The second reaction was between 1,2-dichloroethane and hydrogen over palladium catalyst on alumina support. Formation of two intermediates on the catalyst surface is proposed, which then produced ethane, ethylene, and ethyl chloride. Higher conversion to ethane and ethylene was observed at temperatures above 218°C while conversion to chloroethane is higher at temperatures below 218°C. The activation energy was found to be 15 Kcal/gm-mole. …

An Industrial Ethanol Azeotropic Distillation Process : Modeling, Analysis, And Simulation, Harpreet Singh Chawla

Dissertations

A steady state process simulator with extensive capabilities was developed for the simulation of process plants involving non-ideal multicomponent systems. A comprehensive stand alone program was developed to represent process systems encountering three phases. A computer program was also developed to handle simultaneous regression of vapor-liquid and liquid-liquid equilibria data to estimate the liquid phase activity coefficients via a global set of parameters for the ethanol azeotropic distillation process, using benzene as the entrainer.

An industrial ethanol azeotropic distillation process has been simulated using the developed process simulator (PROSIM). A study of the azeotropic column's aqueous ethanol feed composition reveals …

The Effect Of Single Electrolytes On The Vapor-Liquid Equilibrium Of Mixed Solvents, Peggy Tomasula

Dissertations

A group-contribution model for the prediction of salt-effects on the vapor-liquid equilibria of multicomponent electrolytic solutions containing a single electrolyte is presented. Coulombic interactions are represented through a Pitzer term. Solvation effects and short-range interactions are represented through a UNIQUAC-type expression. An ion-size, a solvation and three ion-solvent interaction parameters per salt-solvent binary are required for multicomponent predictions.

All parameters are obtained only through the correlation of binary salt-solvent osmotic coefficient and vapor-pressure depression data at 25°C, in most cases, and binary solvent VLE data. The salt-solvent binary data were correlated with an average percent error in CD of 2.5 …