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Effects Of Structural And Kinetic Parameters On The Performance Of Chromatographic Columns Packed With Perfusive And Purely Diffusive Adsorbent Particles, G. A. Heeter, Athanasios I. Liapis
Effects Of Structural And Kinetic Parameters On The Performance Of Chromatographic Columns Packed With Perfusive And Purely Diffusive Adsorbent Particles, G. A. Heeter, Athanasios I. Liapis
Chemical and Biochemical Engineering Faculty Research & Creative Works
A mathematical model describing dynamic adsorption in columns with spherical bidisperse perfusive or spherical bidisperse purely diffusive adsorbent particles is used to study the effects of the structural parameters of the adsorbent particles and of the parameters of the adsorption mechanism on the performance of chromatographic systems involving the adsorption of bovine serum albumin onto anion-exchange porous adsorbent particles. Four structural parameters are studied: the particle diameter, d(p), the macropore void fraction, ε(p), the microparticle diameter, d(m) and the parameter φ which affects the value of the permeability of the adsorbent particle. Two parameters of the adsorption mechanism are studied: …
Multi-Component Perfusion Chromatography In Fixed Bed And Periodic Counter Current Column Operation, G. A. Heeter, Athanasios I. Liapis
Multi-Component Perfusion Chromatography In Fixed Bed And Periodic Counter Current Column Operation, G. A. Heeter, Athanasios I. Liapis
Chemical and Biochemical Engineering Faculty Research & Creative Works
A mathematical model of multi-component dynamic adsorption in columns with spherical perfusive and spherical purely diffusive adsorbent particles with a bidisperse porous structure is constructed, solved, and used to study the performance of a binary adsorption system in a single-column fixed-bed process and in a two-column periodic countercurrent process in which the adsorbent is equally distributed over two beds. The total length of the two-column periodic counter-current system is equal to the length of the single-column fixed-bed system. The performance of fixed-bed and periodic counter-current systems with both perfusive and purely diffusive adsorbent particles is examined for different values of …
Modelling And Analysis Of The Elution Stage Of "Perfusion Chromatography" Effects Of Intraparticle Convective Velocity And Microsphere Size On System Performance, Y. Xu, Athanasios I. Liapis
Modelling And Analysis Of The Elution Stage Of "Perfusion Chromatography" Effects Of Intraparticle Convective Velocity And Microsphere Size On System Performance, Y. Xu, Athanasios I. Liapis
Chemical and Biochemical Engineering Faculty Research & Creative Works
A mathematical model describing the dynamic elution (elution stage) in columns with spherical bidisperse perfusive or spherical bidisperse purely diffusive adsorbent particles is presented and its solution is obtained numerically. The desorption of bovine serum albumin (BSA) from spherical anion-exchange porous particles was studied for different values of the intraparticle Peclet numbers of the adsorbate, (Peintra)a, and eluent, (Peintra)e, and of the microsphere diameter, dm. It was found that as (Peintra)a increases, the asymmetry of the elution peak of the adsorbate (at the exit of the column) decreases, the peak height increases and the time, Te, required for the elution …
Comparison Of Trickle-Bed And Upflow Reactor Performance At High Pressure: Model Predictions And Experimental Observations, M. R. Khadilkar, Y. X. Wu, M. (Muthanna) H. Al-Dahhan, M. P. Dudukovic, M. Colakyan
Comparison Of Trickle-Bed And Upflow Reactor Performance At High Pressure: Model Predictions And Experimental Observations, M. R. Khadilkar, Y. X. Wu, M. (Muthanna) H. Al-Dahhan, M. P. Dudukovic, M. Colakyan
Chemical and Biochemical Engineering Faculty Research & Creative Works
Comparison of Laboratory Trickle-Bed and Up-Flow Reactors over a Range of Operating Conditions, Which Cover Both Gas and Liquid Reactant Limitations, Has Been Investigated using Hydrogenation of Alpha-Methylstyrene to Cumene in a Hexane Solvent over 2.5% Pd on Alumina Extrudate Catalyst as a Test Reaction. the Results Show that When the Reaction is Gas Limited at Low Pressure and High Liquid Feed Concentration, Trickle Bed Reactor Outperforms the Upflow Reactor. at High Pressure and Low Liquid Feed Concentration, the Reaction Becomes Liquid Limited and Upflow Reactor Performs Better. It is Concluded that the Advantage of Upflow or Downflow Depends on …
Comparison Of Upflow And Downflow Two-Phase Flow Packed-Bed Reactors With And Without Fines: Experimental Observations, Yuanxin Wu, Mohan R. Khadilkar, Muthanna H. Al-Dahhan, Milorad P. Duduković
Comparison Of Upflow And Downflow Two-Phase Flow Packed-Bed Reactors With And Without Fines: Experimental Observations, Yuanxin Wu, Mohan R. Khadilkar, Muthanna H. Al-Dahhan, Milorad P. Duduković
Chemical and Biochemical Engineering Faculty Research & Creative Works
This Study Compares the Performance of Laboratory Trickle-Bed and Upflow Reactors over a Range of Operating Conditions, using the Hydrogenation of Α-Methylstyrene to Cumene in Hexane Solvent over 2.5% Pd on Alumina Extrudate Catalyst as a Test Reaction. It is Shown that the Trickle Bed Performs Better Than the Upflow Reactor at Low Pressures When the Reaction is Gas Limited, Due to Ready Access of the Gas to the Incompletely Externally Wetted Catalyst, While the Upflow Reactor Performs Better at High Pressures When the Liquid Reactant Limitation Controls the Rate, Due to the Completely Wetted Catalyst. Comparison of the Two …
A Robust Path Tracking Algorithm For Homotopy Continuation, S. H. Choi, D. A. Harney, Neil L. Book
A Robust Path Tracking Algorithm For Homotopy Continuation, S. H. Choi, D. A. Harney, Neil L. Book
Chemical and Biochemical Engineering Faculty Research & Creative Works
Conventional path tracking algorithms used in homotopy continuation systems sometimes miss roots owing to jumping from one segment of the homotopy path to another even if there exists homotopy paths to the roots. A robust path tracking algorithm is proposed which loses significant efficiency only on those portions of the path where segment jumping is likely to occur. The method presented here basically performs the predictor-corrector procedure using the Euler predictor and the Newton corrector. Any available algorithm can be used to control the step size. Robustness is achieved by adding the following rule: control the step size so that …
Modified Contactor For Experimental Studies Of Mass Transfer And Chemical Reaction Across A Liquid-Liquid Interface, Muthanna H. Al-Dahhan, Charles E. Wicks
Modified Contactor For Experimental Studies Of Mass Transfer And Chemical Reaction Across A Liquid-Liquid Interface, Muthanna H. Al-Dahhan, Charles E. Wicks
Chemical and Biochemical Engineering Faculty Research & Creative Works
A Modified Stirred-Cell Type Contactor Has Been Designed and Tested for its Use in Experimental Investigations of Mass Transfer and Chemical Reaction in Liquid-Liquid Systems. its Design overcomes the Shortcomings of Previously Proposed Contactors. It is Easy to Operate and Has the Ability to Investigate the Effect of a Wide Range of Operating Conditions. the Mixing Performance of the Contactor Was Tested using a Dye Injection and a Tracer Technique. Experiments to Evaluate Mass-Transfer Coefficients Across a Liquid-Liquid Interface Have Been Conducted to Determine its Effectiveness. the Results Verified that the Contactor Could Be Successfully Employed as a Useful Experimental …
Catalyst Bed Dilution For Improving Catalyst Wetting In Laboratory Trickle-Bed Reactors, Muthanna H. Al-Dahhan, Milorad P. Duduković
Catalyst Bed Dilution For Improving Catalyst Wetting In Laboratory Trickle-Bed Reactors, Muthanna H. Al-Dahhan, Milorad P. Duduković
Chemical and Biochemical Engineering Faculty Research & Creative Works
The Catalyst Bed Dilution Technique Has Found Rather Widespread Applications as a Means of Producing Reliable and Reproducible Results for Successful Scale-Up and Scale-Down When Testing Commercially Used Catalyst Particle Sizes and Alternative Feedstocks in Small-Scale Laboratory Trickle-Bed Reactors. in Such Small-Diameter Laboratory Units When the Catalyst Used in Commercial Units is Employed as the Only Packing, Low Liquid Velocities Lead to Incomplete Catalyst Utilization Due to Incomplete External Catalyst Wetting, Liquid Maldistribution, and Wall Effects. Diluting the Bed with Fines is Recommended to Remedy These Shortcomings. the Effect of the Bed Dilution with Fines on Catalyst Wetting Efficiency, Pressure …
Evaluation Of Trickle Bed Reactor Models For A Liquid Limited Reaction, Yuanxin Wu, Muthanna H. Al-Dahhan, Mohan R. Khadilkar, Milorad P. Dudukovic
Evaluation Of Trickle Bed Reactor Models For A Liquid Limited Reaction, Yuanxin Wu, Muthanna H. Al-Dahhan, Mohan R. Khadilkar, Milorad P. Dudukovic
Chemical and Biochemical Engineering Faculty Research & Creative Works
The Isothermal Decomposition of Hydrogen Peroxide on a CuCr Catalyst in a Laboratory Scale Trickle Bed Reactor Was Used to Test Model Predictions of the Dependence of Liquid Reactant Conversion on Space Time for Different Operating Conditions. It is Assured that the Decomposition of Hydrogen Peroxide is a First Order Liquid-Limited Reaction. Comparison of Model Predictions and Experimental Data Indicates that Both External Mass Transfer Effects and Incomplete External Catalyst Wetting Need to Be Accounted For. Dudukovic's (1977) Approximate Model for the Catalyst Effectiveness Factor Adequately Simulates Both Effects.
Unsteady Conjugate Mass Transfer Between A Single Droplet And An Ambient Flow With External Chemical Reaction, Leonid S. Kleinman, X. B. Reed
Unsteady Conjugate Mass Transfer Between A Single Droplet And An Ambient Flow With External Chemical Reaction, Leonid S. Kleinman, X. B. Reed
Chemical and Biochemical Engineering Faculty Research & Creative Works
Unsteady conjugate mass transfer between a spherical bubble, droplet, or particle and a surrounding fluid flow with chemical reaction in the continuous phase has been analyzed. An algorithm based on spectral methods has been developed and implemented for the simulation of the interphase mass transfer. The influence of Pe (convection) and Da (rate of external reaction), but in particular of D (diffusivity ratio) and H (distribution coefficient), which characterize the coupling features of the conjugate mass transfer, is studied in a wider range of parameters than earlier investigations. The asymptotic regime of mass transfer is investigated for long times, and …