Chemical Engineering Commons^™

Removal Of Vocs From Air By Absorption And Stripping In Hollow Fiber Devices, Tarun K. Poddar

Dissertations

Large volumes of exhaust air streams contaminated with volatile organic compounds (VOCs) such as toluene, xylene, acetone etc. are discharged into the atmosphere by various industrial facilities. Common technologies for VOC emission abatement e.g., activated carbon adsorption, absorption in a liquid, incineration and catalytic oxidation, have many strengths as well as considerable limitations. In this study, a regenerative absorption-based removal of VOCs from N₂ in an inert, nonvolatile, organic liquid flowing in compact hollow fiber devices has been developed. The process eliminates flooding, loading and entrainment encountered in conventional absorption devices.

Contaminated air/N₂ stream was fed through the …

Computer-Aided Process Design For Waste Minimization, Konstadinos Abeliotis

Dissertations

Problems related to process design with environmental considerations have been studied in this dissertation. A new heuristic design methodology has been formulated with the objective of minimizing the adverse environmental impact of chemical processes.

This hierarchical methodology starts with the definition and analysis of a process flowsheet followed by quantification of the process environmental loads. The quantification of environmental loads is an essential aspect of this methodology, because it serves as the comparative measure for environmental performance.

If the calculated environmental loads do not satisfy the environmental constraints (e.g., regulatory limits), waste minimization is investigated in the following order:

• Pollution …

The Effect Of Chlorine, Sulfur And Phosphorus Compounds On Deactivation Of Palladium Catalysts, Tai-Chiang Yu

Dissertations

The effects of HCl, H₂S, tributyl phosphate (TBP), P₂O₅, and zinc dialkyldithophosphate (ZDP) as catalyst poisons for methane oxidation over palladium catalysts supported on γ-alumina were investigated in this study. The overall reaction rate of methane oxidation over palladium catalysts can be simplified into a pseudo first order reaction under excess oxidation conditions.

The deactivation of the catalyst poisoned by HCl is attributed to the loss of active sites due to volatilization of PdCl₂. H₂ treatment at 200 °C can reactivate the catalyst poisoned by HCl at temperatures of up to …

Biodegradation Of Mixed Wastes : Basic Kinetics And Reaction Engineering For Cyclic Reactor Operation, Kung-Wei Wang

Dissertations

This study dealt with the determination of the detailed kinetics of the biodegradation of mixed substrates by pure cultures, and with reaction engineering studies of bioreactors employed in treatment of substitutable substrates under cyclic operation.

In the first part of the study the degradation of phenol and 4-chlorophenol (4-CP) by two strains of Pseudomonas species was investigated. Strain P. putida 0 was found to be capable of utilizing both phenol and 4-CP as sole carbon and energy sources. This suggests that this strain follows the ortho-cleavage pathway for the aromatic ring. Strain P. putida N could grow on phenol, and …

Experimental And Numerical Determination Of Fluid Velocity Profiles And Turbulence Intensity In Mixing Vessels, Chun-Chiao Chou

Dissertations

In this study, both a laser-Doppler velocimeter (LDV) and a computational fluid dynamic (CFD) software package (FL UENI) were used to experimentally determine and numerically predict the velocity distribution of an unbaffled and a baffled mixing vessel. Two types of impellers were employed, namely a flat blade turbine (FBT) and a pitched blade turbine (PBT). These impellers were studied in a single-impeller or multiple-impeller configuration in the unbaffled and baffled vessels. The flow characteristics in the impeller regions were measured by LDV and used as boundary conditions in the numerical computation. Turbulence effects were numerically simulated using either the k-c …

Combustion Of Methyl Chloride, Monomethyl Amine, And Their Mixtures In A Two Stage Turbulent Flow Reactor, Fuhe Mao

Dissertations

The feasibility of converting fuel-bound chlorine and nitrogen into HCl and N₂ with reduced pollutant emissions of CO, NO, and unburned hydrocarbons was investigated in a two-stage turbulent flow reactor. The study consists of four segments: completion and validation of the experimental facility, experimental and modeling studies of methyl chloride (CH₃Cl) combustion, similar studies on monomethyl amine (CH₃NH₂), and finally studies on simultaneous CH₃Cl and CH₃NH₂ combustion.

Validation of the experimental facility was made by combustion of ethylene (C₂H₄) and air under both fuel-lean …

Oxidation Of Pollutants In A Batch Recirculation Bioreactor With Immobilized Microorganisms, Jongtai Jung

Dissertations

The purpose of this work was to study bio-oxidative destruction of several substrates in an immobilized cell batch bioreactor in recirculation configuration. This system was used in three cases: a series of substrates usually used as monomers, ethylene glycol and its tetramer, and phenol under magnetic irradiation. In addition, kinetic studies were performed and experimental versus predicted results compared.

The substances styrene, methyl methacrylate (MMA), and β-hydroxybutyric acid (HBA), common monomers, were biologically treated using an acclimated mixed microbial community immobilized in calcium alginate gel. A comparison of biodegradation rates (3.3, 9.4, and 15 ppm/hr for styrene, MMA, and HBA, …

Removal Of Vapors From Air By Selective Membrane Processes, Junseok Cha

Dissertations

The behaviors of different membrane modules for the selective removal and recovery of water vapor and some volatile organic compounds (VOCs) from N₂ have been studied. For the selective permeation-based removal of water vapor from N₂, a polymeric water-swollen gel membrane in the form of Cuprophan hollow fiber was employed. A thin film composite type rubbery membrane module was studied for the selective removal of VOCs like toluene or methanol from N₂ by permeation. The usefulness of pore-condensation phenomenon-based removal of toluene or xylene from N₂ was explored using a microporous ceramic tubular membrane.

The …

Engineering Analysis Of A Packed-Bed Biofilter For Removal Of Volatile Organic Compound (Voc) Emissions, Zarook M. Shareefdeen

Dissertations

This study dealt with removal of VOC emissions from airstreams using an evolving new technology which is known as biofiltration. The basis of this technology is biodegradation of VOCs in biofilms formed around porous solids which are placed in packed-bed reactors.

A detailed model describing steady state biofiltration of single and mixed VOCs was developed, and experimentally validated. The model takes into account biodegradation kinetics, the effect of oxygen, kinetic interactions among structurally similar compounds, and mass transfer from the gas phase to the biolayer. It was found that oxygen (a factor neglected in all previous studies) plays a very …

Biological Denitrification : Fundamental Kinetic Studies, And Process Analysis For Sequencing Batch Reactor Operation, Jun-Hsien Wang

Dissertations

This study dealt with a detailed investigation of biological denitrification of nitrate and nitrite by a pure culture of Pseudomonas denitrificans (ATCC 13867), under anaerobic conditions.

In the first part of the study, the kinetics of denitrification were studied in serum-bottle experiments. It was found that reduction of both nitrate and nitrite follows inhibitory expressions of the Andrews type. It was also found that when nitrite is present at levels above 15 mg/L, nitrite and nitrate are involved in a cross-inhibitory, non-competitive, interaction pattern. Analysis of the kinetic data has shown that the culture used has severe maintenance requirements, which …

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 …