Open Access. Powered by Scholars. Published by Universities.®

Chemical Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

Chemical and Biochemical Engineering Faculty Research & Creative Works

Discipline
Keyword
Publication Year
File Type

Articles 601 - 630 of 823

Full-Text Articles in Chemical Engineering

Penn State University Nsf Gk-12 Project: Using Web-Based Education And Interaction With K-12 And College Freshman To Promote Science And Engineering, Elana M. Chapman, Angela D. Lueking, Robin A. Tallon, Philip H. Henning, William S. Carlsen, Daniel C. Haworth Jun 2005

Penn State University Nsf Gk-12 Project: Using Web-Based Education And Interaction With K-12 And College Freshman To Promote Science And Engineering, Elana M. Chapman, Angela D. Lueking, Robin A. Tallon, Philip H. Henning, William S. Carlsen, Daniel C. Haworth

Chemical and Biochemical Engineering Faculty Research & Creative Works

Penn State University has hosted an NSF-sponsored GK-12 Outreach project for the past five years, and has just begun the second phase of the project. The Penn State project utilizes the talents of many science and engineering graduate students as teachers, mentors and role models for the K-12 classrooms. The project focuses on developing skills of students in the areas of science, technology, engineering and mathematics through the use of Advanced Transportation Technologies. A new project component was devised and implemented-the interaction of K-12 students with college freshman via a website project. The college freshmen were asked to create a …

Go to article

Flow Pattern Visualization In A Mimic Anaerobic Digester Using Cfd, Mehul S. Vesvikar, Muthanna H. Al-Dahhan Mar 2005

Flow Pattern Visualization In A Mimic Anaerobic Digester Using Cfd, Mehul S. Vesvikar, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Three-Dimensional Steady-State Computational Fluid Dynamics (CFD) Simulations Were Performed in Mimic Anaerobic Digesters to Visualize their Flow Pattern and Obtain Hydrodynamic Parameters. the Mixing in the Digester Was Provided by Sparging Gas at Three Different Flow Rates. the Gas Phase Was Simulated with Air and the Liquid Phase with Water. the CFD Results Were First Evaluated using Experimental Data Obtained by Computer Automated Radioactive Particle Tracking (CARPT). the Simulation Results in Terms of overall Flow Pattern, Location of Circulation Cells and Stagnant Regions, Trends of Liquid Velocity Profiles, and Volume of Dead Zones Agree Reasonably Well with the Experimental Data. …

Go to article

Experimental Investigation Of The Hydrodynamics In A Liquid-Solid Riser, Shantanu Roy, Abdenour Kemoun, M. (Muthanna) H. Al-Dahhan, M. P. Dudukovic Mar 2005

Experimental Investigation Of The Hydrodynamics In A Liquid-Solid Riser, Shantanu Roy, Abdenour Kemoun, M. (Muthanna) H. Al-Dahhan, M. P. Dudukovic

Chemical and Biochemical Engineering Faculty Research & Creative Works

Liquid-Solid Fluid Dynamics Has Been Investigated in a 6-In. (0.15 M) "Cold-Flow" Circulating Fluidized Bed Riser using Non-Invasive Flow Monitoring Methods. Gamma-Ray Computed Tomography (CT) Was Used to Measure the Time-Averaged Cross-Sectional Solids Volume Fraction Distributions at Several Elevations. the Time-Averaged Mean and "Fluctuating" Solids Velocity Fields Were Quantified using the Computer-Automated Radioactive Particle Tracking (CARPT) Technique. the Experimental Equipment, Protocol of Implementation, and Data Analysis Have Been Discussed Briefly, with Particular Emphasis on the Specific Features in the Use of These Techniques for Studying High-Density Turbulent Flows as in a Liquid-Solid Riser. the Experimental Study Examines Nine Operating Conditions, …

Go to article

Catalytic Wet Air Oxidation Of Phenol In Concurrent Downflow And Upflow Packed-Bed Reactors Over Pillared Clay Catalyst, Jing Guo, Muthanna H. Al-Dahhan Feb 2005

Catalytic Wet Air Oxidation Of Phenol In Concurrent Downflow And Upflow Packed-Bed Reactors Over Pillared Clay Catalyst, Jing Guo, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

An Experimental Study is Presented for Comparing the Behavior of a Packed Bed Reactor in the Catalytic Liquid-Phase Oxidation of Aqueous Phenol with Two Modes of Operation, Downflow and Upflow. the Operating Parameters Investigated Included Temperature, Reactor Pressure, Gas Flowrate, Liquid Hourly Space Velocity and Feed Concentration. Because of the Completely Wetted Catalyst, the Upflow Reactor Generally Performs Better for High Pressures and Low Feed Concentrations When the Liquid Reactant Limitation Controls the Rate. the Interaction between the Reactor Hydrodynamics, Mass Transfer, and Reaction Kinetics is Discussed. for Both Operation Modes, Complete Phenol Removal and Significant Total Organic Carbon (TOC) …

Go to article

Physico-Chemical Characteristics Of European Pulverized Coal Combustion Fly Ashes, N. Moreno, X. Querol, J. M. Andrés, K. Stanton, Mark R. Towler, H. Nugteren, M. Janssen-Jurkovicová, R. Jones Jan 2005

Physico-Chemical Characteristics Of European Pulverized Coal Combustion Fly Ashes, N. Moreno, X. Querol, J. M. Andrés, K. Stanton, Mark R. Towler, H. Nugteren, M. Janssen-Jurkovicová, R. Jones

Chemical and Biochemical Engineering Faculty Research & Creative Works

Fly ashes sourced from European pulverized coal burning power plants (from Spain, The Netherlands, Italy and Greece) were characterized in terms of their chemical composition, mineralogy and physical properties. The amount and composition of the glass present in the ashes were also determined. The materials analyzed have very different compositions and were selected with a view to determining their suitability for different applications and for further studies on applications. The results were compared to the literature to determine their similarities to UK coal fly ashes. Chemical analysis has enabled the categorization of the ashes based on their oxide contents. Devitrification …

Go to article

Flow Distribution Characteristics Of A Gas-Liquid Monolith Reactor Using Computed Tomography, Shaibal Roy, Muthanna H. Al-Dahhan Jan 2005

Flow Distribution Characteristics Of A Gas-Liquid Monolith Reactor Using Computed Tomography, Shaibal Roy, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Flow Distribution Characteristics Were Investigated and Quantified in a 0.05 M Diameter Monolith Reactor, Operated Co-Current Downward in the Taylor Flow Regime, using Gamma Ray Computed Tomography (CT). the Flow Conditions Were Selected to Operate the Reactor in the Taylor Flow Regime and to Bracket Some Commercially Viable Operating Conditions for Such Reactors. Various Operating Parameters Were Evaluated for their Effect on the Degree of Flow Non-Uniformity in the Monolith Crosssection. the Results Show that within the Range of Gas and Liquid Superficial Velocities Investigated, There Exists a Window of Operating Conditions (Intermediate Gas and Liquid Velocities) Which Corresponds to …

Go to article

Phase Distribution In A High Pressure Slurry Bubble Column Via A Single Source Computed Tomography, Novica Rados, Ashfaq Shaikh, Muthanna H. Al-Dahhan Jan 2005

Phase Distribution In A High Pressure Slurry Bubble Column Via A Single Source Computed Tomography, Novica Rados, Ashfaq Shaikh, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Due to their Numerous Advantages, Slurry Bubble Column Reactors (SBCR) Are Gaining Wide Importance in the Petroleum, Petrochemical, Chemical, and Biochemical Industries. Most Previous Literature Studies on the Fluid Dynamics and the Phase Holdup Distribution in SBCR Are Limited to Low Superficial Gas Velocity, Low Solids Loading, and the Atmospheric Pressure. Moreover, the Presence of a Solids Phase Poses Difficulties in Probe Measurement Techniques Such as Pitot Tube and Optical Probe and See through Measurement Techniques Such as Particle Image Velocimetry (PIV), Laser Doppler Velocimetry (LDV). Single Source Γ-Ray Computed Tomography (CT) Has Been Used to Measure Cross-Sectional Phase Holdup …

Go to article

Anisotropic Diffusion Of N-Butane And N-Decane On A Stepped Surface, Shrijay Subramaniyan, Jee-Ching Wang Jan 2005

Anisotropic Diffusion Of N-Butane And N-Decane On A Stepped Surface, Shrijay Subramaniyan, Jee-Ching Wang

Chemical and Biochemical Engineering Faculty Research & Creative Works

The diffusion of single n-butane and n-decane molecules on a model stepped surface, Pt(655), and on a corresponding flat surface, Pt(111), is investigated using molecular-dynamics simulations and anisotropic united atom model. The surface step on Pt(655) causes the alkane molecules to adsorb on the lower terrace in all-trans conformations with their long molecular axes adjacent and parallel to the step edge, and to diffuse anisotropically along the surface step via a constant wiggly motion without rotation or marked deviation from the parallel adsorption configuration. At relatively high temperatures, the alkane molecules can temporarily break away from the step edge but …

Go to article

Measurement And Prediction Of Pressure Drop In Pneumatic Conveying: Effect Of Particle Characteristics, Mass Loading, And Reynolds Number, Kimberly H. Henthorn, Kinam Park, Jennifer S. Curtis Jan 2005

Measurement And Prediction Of Pressure Drop In Pneumatic Conveying: Effect Of Particle Characteristics, Mass Loading, And Reynolds Number, Kimberly H. Henthorn, Kinam Park, Jennifer S. Curtis

Chemical and Biochemical Engineering Faculty Research & Creative Works

This paper reports the effect of Reynolds number, mass loading, and particle shape and size on pressure drop in a vertical gas-solids pneumatic conveying line. We isolate the effect of one variable while holding all others constant. A commonly used pressure drop correlation and a state-of-the-art multiphase computational fluid dynamics (CFD) models are then assessed by comparing their predictions to experimental data. Deficiencies in the models and the correlation are identified, and possible modifications are proposed. The most notable deficiency is the inability of both the experimental correlation and the CFD model to accurately predict the pressure drop for gas-solids …

Go to article

Wetting Kinetics Of Films Containing Non-Adsorbing Polymers, S. Saritha, Xianzhong Zhang, Partho Neogi Jan 2005

Wetting Kinetics Of Films Containing Non-Adsorbing Polymers, S. Saritha, Xianzhong Zhang, Partho Neogi

Chemical and Biochemical Engineering Faculty Research & Creative Works

Kinetics of wetting by a polymer solution have been studied theoretically for a film pinned to a slot. The fluid mechanical equations have been solved using a numerical scheme. The role of polymers appears in the disjoining pressure in the model. The spreading kinetics are observed to follow a power law: a power of (1/4) is observed at short times due to the Laplace pressure, and (1/2) at large times under the Hamaker part of the disjoining pressure at very large times and with no equilibration. It is argued and demonstrated that techniques which have low resolutions such as microscopy …

Go to article

Interfacial Stability Of Electrodeposition Of Cuprous Oxide Thin Films, Partho Neogi Nov 2004

Interfacial Stability Of Electrodeposition Of Cuprous Oxide Thin Films, Partho Neogi

Chemical and Biochemical Engineering Faculty Research & Creative Works

Experiments on deposition of Cu2O films from basic cupper sulfate solution show that copper also deposits. At low, but basic values of pH only copper deposits and at high pH only cuprous oxide deposits. In the intermediate range where both compete the system shows oscillations at "constant current." Linear stability analysis has been conducted for such an electrochemical cell to show that oscillations can take place in the parameter space identified in the experiments. The results are keeping with most of the experimental observations, which are many, but not with all. The physical mechanisms behind the oscillations are …

Go to article

Optimization Of Batch Reactions In Series With Uncertainty, Keith G. Tomazi Nov 2004

Optimization Of Batch Reactions In Series With Uncertainty, Keith G. Tomazi

Chemical and Biochemical Engineering Faculty Research & Creative Works

Certain types of chemical reactions, such as the global deprotection of a polypeptide, are extremely complex. As a result, it may be very difficult or expensive to develop accurate models of these chemical reactions. Without a satisfactory kinetic model for the reaction, it is difficult to develop an optimum operating policy that will maximize the profit. Stochastic optimization is applied in this work to an example process step to obtain the optimum reaction temperature and reaction time. In the case of the "here and now" problem, the optimal conditions are a lower reaction temperature and a longer reaction time than …

Go to article

Monoliths As Multiphase Reactors: A Review, Shaibal Roy, Tobias Bauer, Muthanna H. Al-Dahhan, Peter Lehner, Thomas Turek Nov 2004

Monoliths As Multiphase Reactors: A Review, Shaibal Roy, Tobias Bauer, Muthanna H. Al-Dahhan, Peter Lehner, Thomas Turek

Chemical and Biochemical Engineering Faculty Research & Creative Works

Monolith Reactors Are Being Studied as a Replacement for Conventional Multiphase Reactors Such as Trickle-Bed Reactors, Slurry Reactors, and Slurry Bubble Column Reactors for Gas-Liquid-Solid Reactions. Reactors with Monolith Catalyst Packing Have Been Found to Be Hydrodynamically Superior to Existing Industrial Reactors. This Review Covers Multiphase Reactions Carried Out in Monolith Reactors by Various Researchers. It First Defines the Monolith Reactor and Looks into the Geometrical Aspects of Monolith. the Section Dealing with Hydrodynamics Reviews Pressure Drop, Phase Holdup, Flow Distribution, and Dispersion Characteristics. This Study Also Considers the Tools Used to Characterize the Hydrodynamic Parameters and their Typical Values. …

Go to article

Quantification Of Solids Flow In A Gas-Solid Riser: Single Radioactive Particle Tracking, Satish Bhusarapu, Muthanna H. Al-Dahhan, Milorad P. Dudukovic Nov 2004

Quantification Of Solids Flow In A Gas-Solid Riser: Single Radioactive Particle Tracking, Satish Bhusarapu, Muthanna H. Al-Dahhan, Milorad P. Dudukovic

Chemical and Biochemical Engineering Faculty Research & Creative Works

Solids in Risers of Circulating Fluidized Beds (CFB) Exhibit Local Backflow and Recirculation. Measurement of the Concentration-Time Response to an Impulse Injection of Tracer, Even at Two Elevations Cannot Determine the Residence Time Distribution (RTD) of Solids Uniquely. Hence, Evaluation of RTD in Risers from Conventional Tracer Responses is Difficult and Often Not Possible. in Addition, Estimating the Solids Circulation Rate in These Closed Loop Systems, is a Non-Trivial Problem. in This Work, a Single Radioactive Particle in the CFB Loop is Tracked during its Multiple Visits to the Riser And, by Invoking Ergodicity, Solids Circulation Rate, Accurate Solids RTD …

Go to article

Liquid Holdup And Pressure Drop In The Gas-Liquid Cocurrent Downflow Packed-Bed Reactor Under Elevated Pressures, Jing Guo, Muthanna H. Al-Dahhan Nov 2004

Liquid Holdup And Pressure Drop In The Gas-Liquid Cocurrent Downflow Packed-Bed Reactor Under Elevated Pressures, Jing Guo, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

An Experimental Investigation of the Residence Time Distribution, Liquid Holdup, and Pressure Drop in a Gas-Liquid Downflow Packed Bed Reactor with Porous Particles Operated under Elevated Pressures is Presented. the Effects of the Two-Phase Flow Rates and Reactor Pressures on the External Liquid Holdup and Pressure Drop Are Discussed. a Mechanistic Model, Which Accounts for the Interaction between the Gas and Liquid Phases by Incorporating the Shear and Velocity Slip Factors between Phases, is Employed to Predict the External Liquid Holdup and Pressure Drop for the Experimentally Covered Flow Regime. the Involved Parameters, Such as Shear and Velocity Slip Factors …

Go to article

Determining Suitability Of A Fly Ash For Silica Extraction And Zeolite Synthesis, Natàlia Moreno, Xavier Querol, Angel López-Soler, José Manuel Andres, Maria Janssen, Henk Nugteren, Mark R. Towler, Kenneth Stanton Sep 2004

Determining Suitability Of A Fly Ash For Silica Extraction And Zeolite Synthesis, Natàlia Moreno, Xavier Querol, Angel López-Soler, José Manuel Andres, Maria Janssen, Henk Nugteren, Mark R. Towler, Kenneth Stanton

Chemical and Biochemical Engineering Faculty Research & Creative Works

Zeolitic material is obtained from fly ash both by direct conversion of the ash or from SiO2 extracts obtained from fly ash. This study focuses on determining the suitability of a fly ash for SiO2 extraction and for zeolite synthesis by direct conversion. The SiO2 extraction experiments from different fly ashes show that the main parameters governing the SiO2 extraction are: (a) a high bulk SiO2 content (> 52%, for obtaining an extraction yield of 100 g SiO2 kg-1) in the starting fly ash, (b) a high proportion (> 55%) of the bulk SiO …

Go to article

Induced Defects In Carbonaceous Materials For Hydrogen Storage, Angela D. Lueking, Caroline E. Burgess Clifford, Deepa L. Narayanan Aug 2004

Induced Defects In Carbonaceous Materials For Hydrogen Storage, Angela D. Lueking, Caroline E. Burgess Clifford, Deepa L. Narayanan

Chemical and Biochemical Engineering Faculty Research & Creative Works

The induced defects in carbonaceous materials for hydrogen storage were studied. The effect of exfoliation was studied and the graphite nanofibers (GNF) diameter before and after exfoliation was quantified. Thermal decomposition of the GNF before and after sulfuric/nitric acid exfoliation indicated a clear loss of thermal stability. GNF exfoliation enhanced the hydrogen uptake by a factor of five compared to the untreated GNF. The amorphous carbon was reactive than GNF, and decomposed before the GNF. The higher pretreatment temperature was intended to preferentially remove amorphous carbon leaving a higher purity of exfoliated GNF.

Go to article

Investigation Into The Ultrasonic Setting Of Glass Ionomer Cements : Part Ii Setting Times And Compressive Strengths, E. Twomey, Mark R. Towler, C. M. Crowley, J. Doyle, S. Hampshire Jul 2004

Investigation Into The Ultrasonic Setting Of Glass Ionomer Cements : Part Ii Setting Times And Compressive Strengths, E. Twomey, Mark R. Towler, C. M. Crowley, J. Doyle, S. Hampshire

Chemical and Biochemical Engineering Faculty Research & Creative Works

The ultrasonic setting of glass ionomer cements (GIC) was discussed. It was observed that the ultrasonic setting resulted in improvements of compressive strength. An increase in the PAA molecular weight from PAA50 to PAA200 resulted in an increase in the strength, but with a further increase in the PAA molecular weight to PAA450, there was a reduction in the strength. Results show that the strength of the ultrasonically set materials after 1 day were close to the values for the 7 days chemically set samples.

Go to article

The Influence Of Strontium Substitution In Fluorapatite Glasses And Glass-Ceramics, R. G. Hill, A. Stamboulis, R. V. Law, A. Clifford, Mark R. Towler, C. Crowley May 2004

The Influence Of Strontium Substitution In Fluorapatite Glasses And Glass-Ceramics, R. G. Hill, A. Stamboulis, R. V. Law, A. Clifford, Mark R. Towler, C. Crowley

Chemical and Biochemical Engineering Faculty Research & Creative Works

Strontium is often substituted for calcium in order to confer radio-opacity in glasses used for dental cements, Biocomposites and bio glass-ceramics. The present paper investigates the influence of substituting strontium for calcium in a glass of the following composition: 4.5SiO23Al2O 31.5P2O53CaO2CaF2, having a Ca:P ratio of 1.67 corresponding to calcium fluorapatite (Ca5(PO 4)3F). The glasses were characterized by magic angle spinning nuclear magnetic resonance (MAS-NMR), by differential scanning calorimetry (DSC) and X-ray powder diffraction (XRD). The 29Si, 27Al and 31P NMR spectra for the glasses with …

Go to article

Characterisation Of The Glass Fraction Of A Selection Of European Coal Fly Ashes, J. Henry, Mark R. Towler, K. T. Stanton, X. Querol, N. Moreno May 2004

Characterisation Of The Glass Fraction Of A Selection Of European Coal Fly Ashes, J. Henry, Mark R. Towler, K. T. Stanton, X. Querol, N. Moreno

Chemical and Biochemical Engineering Faculty Research & Creative Works

Fly ash largely consists of the inorganic content of coal that remains after combustion. The crystalline phases present in fly ash may form upon cooling of a molten alumino-silicate glass. This view is supported by the spherical shape of many fly ash particles, inferring that they have gone through a viscous fluid state. The amorphous content in fly ash is believed to dominate reactivity behaviour, under both alkaline and acid conditions, because glasses have a higher potential energy than the equivalent crystal structure and the variation of bond angles and distances in a glass makes the bond breakage easier. It …

Go to article

A Sequential Approach To Modeling Catalytic Reactions In Packed-Bed Reactors, Jing Guo, Muthanna H. Al-Dahhan May 2004

A Sequential Approach To Modeling Catalytic Reactions In Packed-Bed Reactors, Jing Guo, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

A Sequential Modeling Approach is Proposed to Simulate Catalytic Reactions in Packed-Bed Reactors. the Hydrogenation of Alpha-Methylstyrene and Wet Oxidation of Phenol Are Selected as Studied Cases. the Modeling Scheme Combines a Reactor Scale Axial Dispersion Model with a Pellet Scale Model. Without Involving Any Fitting Parameters, Such an Approach Accounts for the Non-Linear Reaction Kinetics Expression and Different Types of Pellet-Liquid Wetting Contact. to Validate the Developed Modeling Scheme and the Parallel Approach Reported in the Literature, the Experimental Observations for Hydrogenation of Alpha-Methylstyrene to Cumene Have Been Employed. the Predicted Results by Both Approaches Agree Reasonably with the …

Go to article

Dynamic Contact Angles Under Evaporation, Robert M. Ybarra, Partho Neogi Mar 2004

Dynamic Contact Angles Under Evaporation, Robert M. Ybarra, Partho Neogi

Chemical and Biochemical Engineering Faculty Research & Creative Works

Wetting kinetics in the presence of heat transfer, evaporation, and Marangoni effect has been explored using a method used by Joanny and de Gennes [C. R. Acad. Sci. Ser. II 299, 279 (1984)]. The method solves for the dynamic contact angle alpha by equating the rate of surface work to the rate of dissipation. The result in the form of dynamic contact angle alpha as a function of capillary number Ca agrees well with existing experimental data. Qualitative comparisons have been made in cases where quantitative data do not exist. Finally, a form of contact line instability is predicted, for …

Go to article

Analyzing And Modeling Of Photobioreactors By Combining First Principles Of Physiology And Hydrodynamics, Hu Ping Luo, Muthanna H. Al-Dahhan Feb 2004

Analyzing And Modeling Of Photobioreactors By Combining First Principles Of Physiology And Hydrodynamics, Hu Ping Luo, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Mixing in Photobioreactors is Known to Enhance Biomass Productivity Considerably, and Flow Dynamics Play a Significant Role in the Reactor's Performance, as They Determine the Mixing and the Cells' Movement. in This Work We Focus on Analyzing the Effects of Mixing and Flow Dynamics on the Photobioreactor Performance. based on Hydrodynamic Findings from the CARPT(Computer Automated Radioactive Particle Tracking) Technique, a Possible Mechanism for the Interaction between the Mixing and the Physiology of Photosynthesis is Presented, and the Effects of Flow Dynamics on Light Availability and Light Intensity Fluctuation Are Discussed and Quantitatively Characterized. Furthermore, a Dynamic Modeling Approach is …

Go to article

Kinetics Of Wet Air Oxidation Of Phenol Over A Novel Catalyst, Jing Guo, Muthanna H. Al-Dahhan Oct 2003

Kinetics Of Wet Air Oxidation Of Phenol Over A Novel Catalyst, Jing Guo, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Wet Air Oxidation Kinetics of an Aqueous Solution of Phenol Was Studied over Extrudates of an Al-Fe Pillared Clay Catalyst in the Temperature Range of 90-150°C and Air Pressure Range of 0.8-2.5 MPa. the Variables Studied Included Reaction Temperature, Air Pressure, Solution PH, Initial Phenol Concentration, and Catalyst Loading. the Obtained Findings Are Compared with Those Obtained using Hydrogen Peroxide Oxidation. a Group of Kinetic Models Considering Both the Power-Law and Langmuir-Hinshelwood Approaches Was Evaluated to Describe the Catalytic Kinetics of the Phenol Disappearance. the Nonlinear Dependence of the Phenol Conversion Rate on the Catalyst Concentration Was Taken into …

Go to article

Preliminary Work On The Antibacterial Effect Of Strontium In Glass Ionomer Cements, A. Guida, Mark R. Towler, J. G. Wall, R. G. Hill, S. Eramo Oct 2003

Preliminary Work On The Antibacterial Effect Of Strontium In Glass Ionomer Cements, A. Guida, Mark R. Towler, J. G. Wall, R. G. Hill, S. Eramo

Chemical and Biochemical Engineering Faculty Research & Creative Works

The antibacterial effect of strontium in glass ionomer cements (GIC) was discussed. The glass transition temperatures were found to decrease with the increasing fluorine content consistent with the fluorine replacing bridging oxygens. However no significant correlation was found between the fluoride release and the antibacterial activity.

Go to article

Computation Of Effectiveness Factors For Partially Wetted Catalyst Pellets Using The Method Of Fundamental Solution, E. Palmisano, P. A. Ramachandran, K. Balakrishnan, M. (Muthanna) H. Al-Dahhan Oct 2003

Computation Of Effectiveness Factors For Partially Wetted Catalyst Pellets Using The Method Of Fundamental Solution, E. Palmisano, P. A. Ramachandran, K. Balakrishnan, M. (Muthanna) H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Trickle Bed Reactors Are Widely Used in Many Process Industries. the Catalyst Particles Are Often Incompletely Wetted Especially in the Trickling Flow Regime and Hence to Design These Reactors, the Effectiveness Factor of Partially Wetted Catalyst Needs to Be Calculated Accurately. Numerical Solutions by Traditional Methods Are Time Consuming and Not Very Accurate, Especially for Some Commonly Used Complex Catalyst Shapes Such as Trilobes, Quadrilobes Etc. the Paper Presents a Novel Numerical Solution for These Problems based on the Method of Fundamental Solutions. the Advantage of the Method is that It Involves Only Boundary Collocation and Can Be Applied to …

Go to article

Expressions For Evaluating The Possibility Of Slip At The Liquid-Solid Interface In Open Tube Capillary Electrochromatography, B. A. Grimes, Athanasios I. Liapis Jul 2003

Expressions For Evaluating The Possibility Of Slip At The Liquid-Solid Interface In Open Tube Capillary Electrochromatography, B. A. Grimes, Athanasios I. Liapis

Chemical and Biochemical Engineering Faculty Research & Creative Works

In this work, expressions are constructed and solved that describe the velocity field of electroosmotic flow (EOF) in open tube capillary electrochromatography (CEC) systems when the possibility of having unequal tangential velocities at the liquid-solid interface is considered and a slip condition is employed as a boundary condition for the velocity of the EOF at the capillary wall. the coupled equations of hydrodynamics (momentum balance equation) and electrostatics (Poisson equation) are solved numerically in order to obtain the distribution of the velocity field as well as the value of the volumetric flow rate in the open tube. Also, expressions for …

Go to article

Catalytic Wet Oxidation Of Phenol By Hydrogen Peroxide Over Pillared Clay Catalyst, Jing Guo, Muthanna H. Al-Dahhan Jun 2003

Catalytic Wet Oxidation Of Phenol By Hydrogen Peroxide Over Pillared Clay Catalyst, Jing Guo, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Extrudates of Al-Fe Pillared Clay Catalyst Suitable for Packed-Bed Operations Are Evaluated for Wastewater Treatment Via a Wet Oxidation Process Employing Hydrogen Peroxide as the Oxidant. the Reaction Was Carried Out in a Semibatch Basket Reactor under Rather Mild Conditions. Operational Parameters Were Studied under the Following Conditions: Temperature from 25 to 90 °C, Atmospheric Pressure, Initial Phenol Concentration from 100 to 2000 Ppm of the Liquid Phase, Catalyst Loading from 0 to 10 G/L, and Input H2O2 Concentration from 0.15 to 0.6 Mol/L. under These Conditions, the Al-Fe Pillared Clay Catalyst Achieves a Total Elimination of Phenol and Significant …

Go to article

Environmental Sustainability Education At The University Of Michigan: Collaboration With Industry To Provide Experiential Learning Opportunities, Angela D. Lueking, Deborah A. Ross, Walter Weber Jr Jun 2003

Environmental Sustainability Education At The University Of Michigan: Collaboration With Industry To Provide Experiential Learning Opportunities, Angela D. Lueking, Deborah A. Ross, Walter Weber Jr

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Concentrations in Environmental Sustainability (ConsEnSus) Program at the University of Michigan is a new multi-disciplinary opportunity for graduate students in the College of Engineering to pursue interests in environmental sustainability white obtaining a traditional engineering Master's degree. Students from several engineering departments complement traditional disciplinary course requirements with courses in environmental regulations, policies, and technology. A required case studies course of the ConsEnSus Program brings practicing engineers together with students to discuss real-world sustainability problems. The industrial participants interactively present relevant case studies, and provide opportunities for experiential learning through classroom activities and term projects. This paper …

Go to article

Shape-Controlled Synthesis Of Iron Oxide Nanoparticles, Yangchuan Xing, T. P. Kole, J. L. Katz Jun 2003

Shape-Controlled Synthesis Of Iron Oxide Nanoparticles, Yangchuan Xing, T. P. Kole, J. L. Katz

Chemical and Biochemical Engineering Faculty Research & Creative Works

A study on shape-controlled synthesis of iron oxide nanoparticles was presented. a specially designed counterflow diffusion flame (CDF) reactor was used to synthesize the iron oxide nanoparticles. It was observed that the properties of surface atoms on the nanoparticles are associated with the chemical environments, leading to the preferential growth of a particular crystallographic surface.

Go to article

First Prev Next Last