Chemical Engineering Commons^™

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 …

Removal Of Vocs From Waste Gas Streams By A Hollow Fiber Permeator, Varinder Pal Malik

Theses

Removal of various VOCs from air/nitrogen feed streams using a novel hollow fiber membrane was studied. Hollow Fiber Module (HFM) used had composite silicone membranes wherein an ultrathin (~ 1μm), nonporous silicone rubber membrane layer had been plasma polymerized on a porous (porosity: 0.4) polypropylene substrate. VOCs studied were toluene, methanol, acetone, methylene chloride and hexane. Primary focus was on single VOCs, although separation of VOC mixtures was also briefly studied. HFM was found to be extremely effective in removing various VOCs from feed streams. Removal of 90-99 % of various VOCs was achieved at low feed flow rates and …

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 …

A Comparison Of Anhydrous Ethanol Production From Ethylene And From Corn Utilizing Life Cycle Analysis Methodology, Gregory Morse

Theses

There is currently much concern with the impact on the environment due to industrial processes. One method to assess this impact is to perform a Life Cycle Analysis (LCA) on the process. Life Cycle Analysis is made up of three stages; Life Cycle Inventory Analysis, Life Cycle Impact Assessment, and Life Cycle Improvement Assessment. In this study, Life Cycle Inventory Analysis methodology was applied to two industrial processes for producing anhydrous ethanol. The first process is the fermentation of corn, and the second is the hydration of ethylene using water and a catalyst. Each process was first modeled using the …

Modeling The Fate Of Volatile Organic Compounds In Wastewater Treatment Facilities; Implementation Of Volatilization Models In Envirocad, Vinita Chhahira

Theses

The 1990 Clean Air Act Amendments have identified wastewater treatment facilities as a major source of volatile organic compound (VOC) emissions. VOCs present in wastewater discharges affect the quality of receiving waters, while emissions to the air affect downwind populations. The primary mechanisms involved in VOC removal from a wastewater treatment facility are volatilization and stripping, biodegradation, and sorption to either suspended or biological solids. Although many models have been developed to predict the fate of VOCs in wastewater treatment facilities, no model completely predicts emissions for an entire wastewater treatment facility. The focus of this work is to incorporate …

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 …

Volatilization Of Volatile Organic Compounds From Complex Wastewaters, Syed Sikandar Qadry

Theses

A variety of volatile organic solvents used in the pharmaceutical and specialty chemical industries end up in wastewater collection and treatment systems. EPA has classified these VOCs into groups depending on their potential to volatilize from the wastewaters. In making this classification, Henry's Law, which is valid at very low concentrations, has been used to describe the vapor-liquid equilibrium. But, in reality the concentrations observed in the wastewaters are often too high for Henry's Law to be valid and it is inappropriate to assume that equilibrium has been achieved for every compound.

This project evaluates the volatilization rates, both experimental …

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 …

A Study Of The Biofiltration Process Under Shock-Loading Conditions, Helen Androutsopoulou

Theses

Biofiltration is a new technology for treating airstreams contaminated with emissions of volatile organic compounds (VOCs). It employs porous particles which are placed in reactors, in packed-bed configurations, after appropriate microorganisms have been immobilized on the solid support.

Biofiltration involves complex processes, and is not yet well understood. In this thesis the response of biofilter units to quantitative and qualitative changes in the inlet airstreams was examined. Steady state data were also analyzed through the use of an existing detailed model.

Experiments were performed with two small-scale biofilters, and with ethanol and butanol as model compounds. Each biofilter was dedicated …

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. …

Agitation Requirements For Complete Liquid Dispersion In Liquid-Liquid-Gas Systems, Emad Ahmad Abu-Hakmeh

Theses

A number of studies have been published in the literature on the determination of the agitation intensity at which two immiscible liquids become completely dispersed in mechanically agitated vessels. However, no information is currently available on the agitation intensity required for the complete dispersion of two liquids in the presence of an additional gas phase. Therefore, the main objective of this study was to experimentally determine the minimum agitation speed for complete liquid-liquid dispersion, N_cd, in liquid-liquid-gas systems as a function of gas flow rate, impeller type, impeller size, and impeller off-bottom clearance. The minimum agitation speed was …

The Development Of A Senior Unit Operations Laboratory On The Supercritical Extraction Of Solid Naphthalene With Supercritical Carbon Dioxide, Ronald G. Gabbard

Theses

A Senior level Undergraduate Unit Operations Laboratory experiment was developed for the extraction of Naphthalene with supercritical Carbon Dioxide. A Supercritical Extraction Screening System purchased from Autoclave Engineers of Erie, Pennsylvania was modified slightly for use as the laboratory equipment. The experiment consists of extracting solid naphthalene from a sand bed in a fixed bed extractor and determining the mass transfer coefficient for the unit.

The lab has been designed to allow the students to develop their own experimental plan without much direct input. The experimental outline provided for the students primarily focuses on information needed for safe and proper …

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 …

Investigation Of The Effects Of Methyl Chloride Addition On Premixed, Laminar, Methane/Air Flat Flames, Limin Wang

Theses

Temperatures and the concentrations of stable species, such as CO, CO₂, CH₄, and CH3Cl, have been measured over the height above burner at equivalence ratio of 0.79 (fuel lean) and 1.20 (fuel rich) for premixed, laminar CH₄/air and CH₃Cl/CH₄/air flat flames. A water-cooled quartz sampling micro-probe and gas chromatographic analysis were used for the concentration measurements. Chemical kinetic modeling of these flames with a 279-reaction, 63-species elementary reaction mechanism is performed using the CHEMKIN premixed flat flame code. The results of rate-of-production calculations are analyzed to determine the most important …

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 …

Pressure Swing Absorption-Based Separation Of A Gas Mixture, Syamalendu Bhaumik

Theses

In this study, separation of a gas mixture was investigated using the novel concept of pressure swing absorption in a stationary absorbent liquid. The best features of pressure swing adsorption, gas liquid scrubbing and hollow fiber based membrane processes were incorporated to develop the process.

A well-packed microporous hydrophobic hollow fiber module was used to achieve absorption of a gas at a high pressure into a liquid during a certain part of the cycle followed by desorption of the gas from the liquid in the other part of the cycle. The device has a very high interfacial area per unit …

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 …

Removal Of Volatile Organic Compounds (Voc's) Acetone And Ethyl Alcohol Emitted In The Manufacture Of A Multi-Base Propellant, Yih-Leu Liu

Theses

The Production Base Modernization Activity located at Picatinny Arsenal, initiated this study for the removal of the low concentrations of VOC's, acetone and ethyl alcohol emitted from the mixer operation and the forced air dry unit in the manufacture of a multi -base propellant. Air pollution requirements necessitate 85 % removal of the VOC's prior to discharge of the vent gases into the atmosphere. Because of the availability of sulfuric acid, it is proposed to use 70 percent or stronger acid as the absorbing agent in a recirculating acid absorption tower.

Vapor - Liquid Equilibrium ( VLE ) data were …

Mineralization Of 2-Chlorophenol Using A Hollow Fiber Ultrafiltration System In Combination With A Reactor Containing An Immobilized White Rot Fungus, Sheau-Ming Tung

Theses

Phanerochaete chrysosporium, a white rot fungus was immobilized on a packed-bed reactor, and was used to mineralize an aqueous stream contaminated with 50 ppm of 2-chlorophenol. Hollow fiber ultrafiltration membranes (for 5,000 daltons and 10,000 daltons molecular weight cut-oft) were utilized to retain the extracellular enzyme resulting from the immobilized fungus in a recirculation loop outside of the reactor.

It was found here that the concentration of proteins (roughly proportional to the extracellular enzyme releasd by the fungus) does not correlate with the rate of degradation of 2-chlorophenol in the system. The protein was concentrated 1.5 fold in the recycle …

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. …

Pure Strong Competition For Two Microbial Populations In A Chemostat, Efthimios Ioannis Banias

Theses

The dynamics of pure, strong, double competition between two microbial populations in an ideal chemostat have been investigated by using mathematical and numerical analysis. The two nutrients competed for have been assumed to be complementary for both competitors. Inter active models have been used for the specific growth rates. Two cases have been considered; one in which neither of the two substrates exerts inhibitory effects on the growth of either one of the competing populations, and one in which the growth of one population is inhibited by only one of the two substrates. The primary focus of this investigation was …