Engineering Commons^™

Dynamic Multi-Dimensional Numerical Transport Study Of Lithium-Ion Battery Active Material Microstructures For Automotive Applications, Joseph S. Lopata, Taylor R. Garrick, Fengkun Wang, Han Zhang, Yangbing Zeng, Sirivatch Shimpalee

Faculty Publications

In support of GM’s traction battery efforts, we derived and implemented a method to describe the electrochemical performance of a battery cell considering the nuances of the electrode microstructure at the anode and the cathode and the corresponding impact on the electrochemical transport in the solid and liquid phases. To assess the capability of the method, we compared model results from the microstructure framework with the commonly used continuum-level porous electrode model, commonly referred to as the pseudo-2-dimensional model, or the Newman Model. The microstructure modeling framework was applied to simulate the electrochemical and transport processes within the battery cell …

Pretreatment Of Corncob With Green Deep Eutectic Solvent To Enhance Cellulose Accessibility For Energy And Fuel Applications, Sanphawat Phromphithak, Nakorn Tippayawong, Thossaporn Onsree, Jochen A. Lauterbach

Faculty Publications

Fossil fuels are the primary source of energy for a long period in spite of excessive environmental hazards, such as greenhouse gas emissions. Production of energy and fuel from lignocellulosic biomass has been the goal of the study in pursuit of renewable alternatives to fossil materials. Corncob is common agricultural biomass waste found in many countries. It can be utilized to produce bioenergy, but the conversion efficiency is limited. Pretreatment may be applied to improve the efficiency of corncob conversion; for example, by the fractionation of lignocellulosic biomass. Choline chloride (ChCl) and glycerol are considered as synthetic deep eutectic solvents …

Chiral Liquid Crystal Microdroplets For Sensing Phospholipid Amphiphiles, Sepideh Norouzi, Jose A. Martinez Gonzalez, Monirosadat Sadati

Faculty Publications

Designing simple, sensitive, fast, and inexpensive readout devices to detect biological molecules and biomarkers is crucial for early diagnosis and treatments. Here, we have studied the interaction of the chiral liquid crystal (CLC) and biomolecules at the liquid crystal (LC)-droplet interface. CLC droplets with high and low chirality were prepared using a microfluidic device. We explored the reconfiguration of the CLC molecules confined in droplets in the presence of 1,2-diauroyl-sn-glycero3-phosphatidylcholine (DLPC) phospholipid. Cross-polarized optical microscopy and spectrometry techniques were employed to monitor the effect of droplet size and DLPC concentration on the structural reorganization of the CLC molecules. Our results …

Chiral Liquid Crystal Microdroplets For Sensing Phospholipid Amphiphiles, Sepideh Norouzi, Jose A. Martinez Gonzalez, Monirosadat (Sanaz) Sadati

Faculty Publications

Designing simple, sensitive, fast, and inexpensive readout devices to detect biological molecules and biomarkers is crucial for early diagnosis and treatments. Here, we have studied the interaction of the chiral liquid crystal (CLC) and biomolecules at the liquid crystal (LC)-droplet interface. CLC droplets with high and low chirality were prepared using a microfluidic device. We explored the reconfiguration of the CLC molecules confined in droplets in the presence of 1,2-diauroyl-sn-glycero3-phosphatidylcholine (DLPC) phospholipid. Cross-polarized optical microscopy and spectrometry techniques were employed to monitor the effect of droplet size and DLPC concentration on the structural reorganization of the CLC molecules. Our results …

Koh Vs Deionized Water Operation In Anion Exchange Membrane Electrolyzers, Noor Ul Hassan, Yiwei Zheng, Paul A. Kohl, Mustain E. William

Faculty Publications

Anion exchange membrane water electrolyzers (AEMELs) have recently received significant attention due to their potential advantages over proton exchange membrane electrolyzers (PEMELs). However, some AEMELs feed an aqueous salt solution to the cell where PEMELs typically feed deionized (DI) water. DI water is preferred to keep the system and maintenance costs low. Because of this, many AEMEL researchers report performance both in the salt solution (typically KOH) and DI water. However, the methodology for switching between KOH and DI water is often poorly defined, and it is unclear what impact the residual salt has on cell performance after switching from …

Editorial For Gels 6th Anniversary Special Issue, Esmaiel Jabbari, Gulden Camci-Unal

Faculty Publications

Note: In lieu of an abstract, this is an excerpt from the first page.

This Special Issue celebrates many outstanding quality papers published in Gels over the past six years since its first issue was published in 2015 [...]

Antiviral Polymers: A Review, Ali Akbari, Ashkan Bigham, Vahid Rahimkhoei, Sina Sharifi, Esmaiel Jabbari

Faculty Publications

Polymers, due to their high molecular weight, tunable architecture, functionality, and buffering effect for endosomal escape, possess unique properties as a carrier or prophylactic agent in preventing pandemic outbreak of new viruses. Polymers are used as a carrier to reduce the minimum required dose, bioavailability, and therapeutic effectiveness of antiviral agents. Polymers are also used as multifunctional nanomaterials to, directly or indirectly, inhibit viral infections. Multifunctional polymers can interact directly with envelope glycoproteins on the viral surface to block fusion and entry of the virus in the host cell. Polymers can indirectly mobilize the immune system by activating macrophages and …

Editorial For Gels 6th Anniversary Special Issue, Esmaiel Jabbari, Gulden Camci-Unal

Faculty Publications

No abstract provided.

Simplified Thermal Runaway Model For Assisting The Design Of A Novel Safe Li-Ion Battery Pack, Paul T. Coman, Eric C. Darcy, Ralph E. White

Faculty Publications

This paper presents a simplified thermal runaway model (FEM) used to guide the design of a novel battery pack designed to resist thermal runaway propagation passively. The model is based on the heat equation for a 2D geometry with a heat generation term based on the maximum amount of energy measured using a custom-made calorimeter. The model was validated against experimental data using a 48-cell subscale of a full-scale battery pack for three different runs with three trigger cells with Internal Short Circuit Devices (ISCD) implanted in the separators. One trigger cell was placed at the edge, one placed in …

Kinetic And Thermodynamic Analyses For Pyrolysis Of Hemp Hurds Using Discrete Distributed Activation Energy Model, Panuphong Mankeed, Thossaporn Onsree, Salman Raza Naqvi, Sirivatch Shimpalee, Nakorn Tippayawong

Faculty Publications

In many counties, hemp is becoming a high-valued economic crop. Post-processing, more than 65% w/w of its starting material becomes waste. Herein, pyrolysis of hemp hurds/residues was investigated under low (10-50 degrees C/min) and intermediate (100-150 degrees C/min) heating rates using a discrete distributed activation energy model (DAEM). Thermochemical decomposition of hemp hurds occurred in three stages: drying, active pyrolysis, and char formation, accounting for 70-80% w/w overall weight loss. With the discrete DAEM, the model can be utilized for predicting pyrolysis behaviors of hemp hurds accurately with correlation coefficient of over 0.99. Different reaction mechanisms appeared between the low …

Decellularized Articular Cartilage Microgels As Microcarriers For Expansion Of Mesenchymal Stem Cells, Esmaiel Jabbari, Azadeh Sepahvandi

Faculty Publications

Conventional microcarriers used for expansion of human mesenchymal stem cells (hMSCs) require detachment and separation of the cells from the carrier prior to use in clinical applications for regeneration of articular cartilage, and the carrier can cause undesirable phenotypic changes in the expanded cells. This work describes a novel approach to expand hMSCs on biomimetic carriers based on adult or fetal decellularized bovine articular cartilage that supports tissue regeneration without the need to detach the expanded cells from the carrier. In this approach, the fetal or adult bovine articular cartilage was minced, decellularized, freeze-dried, ground, and sieved to produce articular …

A Reduced-Order Lumped Model For Li-Ion Battery Packs During Operation, Paul T. Coman, Eric C. Darcy, Brad Strangways, Ralph E. White

Faculty Publications

Modeling heat distribution in Li-ion battery packs can be challenging, especially if the battery pack is large and the cells are operated at high C-rates, which usually requires high-order physics-based mathematical models. Reduced and simplifying models can, however, be used at lower rates. This paper presents a fast novel reduced lumped model (RLM) that can be used to calculate the temperature increase during the high-current discharge of cylindrical Li-ion cells in a subscale of a battery pack. By reducing the PDE utilized to calculate the state of charge (SoC) to ODE's and solving them analytically, the reduced model can be …

Investigating Influence Of Geometry And Operating Conditions On Local Current, Concentration, And Crossover In Alkaline Water Electrolysis Using Computational Fluid Dynamics, J. S. Lopata, S-G. Kang, H-S. Cho, C-H. Kim, J. W. Weidner, Sirivatch Shimpalee

Faculty Publications

We use a three-dimensional computational fluid dynamics model to examine the liquid saturation, KOH concentration, and gas crossover in an alkaline diaphragm water electrolysis device. The effects of cell potential, solution feed rate, and aspects of the design such as the locations and widths of channels on performance and crossover were studied. The results build a case for implementing a separator transport model and an electrode/separator interface model because of the concentration changes observed at the anode and cathode. Simulations suggest a strong relationship between solution feed rate and the nature of dissolved gas crossover through the diaphragm due to …

The Effects Of Ceria Loading On Three-Way Catalysts For Passive Scr Operation, Calvin R. Thomas, Josh A. Pihl, Vitaly Y. Prikhodko, Michelle K. Kidder, Jochen A. Lauterbach, Todd J. Toops

Faculty Publications

Passive SCR systems, which employ both a three-way catalyst and SCR catalyst, are effective for the reduction of nitrogen oxide (NOx) emissions from lean burn gasoline engines. However, questions remain regarding the effect of three-way catalyst formulations on their performance in these systems. Here, Pd/CeOx/Al2O3 catalysts with variable CeOx loading were synthesized, characterized, and evaluated to determine the effects of CeOx on catalyst performance. While a small amount of ceria was beneficial for promoting essential reactions, excess ceria was detrimental due to the increase in oxygen storage capacity. Additionally, insights into potential reaction pathways for NH3 production were determined.

Mixing Optimization With Inward Flow Configuration Contra-Rotating Impeller, Baffle-Free Tank, P. Satjaritanun, J. R. Regalbuto, J. A. Regalbuto, N. Tippayawong, Sirivatch Shimpalee

Faculty Publications

In this study, pitched-blade, contra-rotating impeller, baffle-free tank with opposing inward flow is optimized using various designs of mixers derived from the Taguchi method. Mixing efficiency and torque are used to find the optimal design for the different specific gravities of solid particles employing in both experiments and CFD simulations. The analysis of signal-to-noise ratio shows that the impeller clearance and diameter are significant factors on the fluid flow and thus the mixing efficiency. In this study, 27 cases were studied to determine and report the optimal design parameters. A combination of CFD simulation with a strong design of experiment …

The Effects Of Ceria Loading On Three-Way Catalysts For Passive Scr Operation, Calvin R. Thomas, Josh A. Pihl, Vitaly Y. Prikhodko, Michelle K. Kidder, Jochen A. Lauterbach, Todd J. Toops

Faculty Publications

Passive SCR systems, which employ both a three-way catalyst and SCR catalyst, are effective for the reduction of nitrogen oxide (NOx) emissions from lean burn gasoline engines. However, questions remain regarding the effect of three-way catalyst formulations on their performance in these systems. Here, Pd/CeOx/Al2O3 catalysts with variable CeOx loading were synthesized, characterized, and evaluated to determine the effects of CeOx on catalyst performance. While a small amount of ceria was beneficial for promoting essential reactions, excess ceria was detrimental due to the increase in oxygen storage capacity. Additionally, insights into potential reaction pathways for NH3 production were determined.

The Impact Of Micro Porous Layer On Liquid Water Evolution Inside Pemfc Using Lattice Boltzmann Method, Mitchell Sepe, P. Satjaritanun, I. V. Zenyuk, N. Tippayawong, Sirivatch Shimpalee

Faculty Publications

Proton exchange membrane fuel cells (PEMFCs) require a gas diffusion layer to aid in fuel transport to the catalyst sites. A microporous layer (MPL) is often added to the GDL to improve liquid saturation inside gas diffusion media. In this work, the lattice Boltzmann method was applied to four GDL samples with the addition of an MPL. Three injection orientations were used to study liquid evolution through the samples. Each orientation used four different injection pressures, ranging from 5,000 Pa to 8,000 Pa. Saturation data for GDL samples with and without an MPL were compared. Results showed that when adding …

Nanoparticles For Targeted Drug Delivery To Cancer Stem Cells: A Review Of Recent Advances, Yavuz Nuri Ertas, Keyvan Abedu Dorcheh, Ali Akbari, Esmaiel Jabbari

Faculty Publications

Cancer stem cells (CSCs) are a subpopulation of cells that can initiate, self-renew, and sustain tumor growth. CSCs are responsible for tumor metastasis, recurrence, and drug resistance in cancer therapy. CSCs reside within a niche maintained by multiple unique factors in the microenvironment. These factors include hypoxia, excessive levels of angiogenesis, a change of mitochondrial activity from aerobic aspiration to aerobic glycolysis, an upregulated expression of CSC biomarkers and stem cell signaling, and an elevated synthesis of the cytochromes P450 family of enzymes responsible for drug clearance. Antibodies and ligands targeting the unique factors that maintain the niche are utilized …

Resolving Anodic Current And Temperature Distributions In A Polymer Electrolyte Membrane Water Electrolysis Cell Using A Pseudo-Two-Phase Computational Fluid Dynamics Model, J. Lopata, Z. Kang, J. Young, G. Bender, J. W. Weidner, H-S. Cho, Sirivatch Shimpalee

Faculty Publications

Expanding upon our prior experimental work, we constructed a three-dimensional model of a polymer electrolyte membrane water electrolyzer using computational fluid dynamics. We applied the assumption of pseudo-two-phase flow, the flow of two phases with equal velocity. Experimental data were used to obtain parameters and to determine the conditions under which this model was valid. Anodic distributions of current density, temperature, liquid saturation, and relative humidity were obtained at various flow rates. The overall current density and temperature difference from inlet to outlet at the anode agreed strongly with experimental measurements under most circumstances. This verification allowed us to further …

Editors’ Choice-Examining Performance And Durability Of Anion Exchange Membrane Fuel Cells With Novel Spirocyclic Anion Exchange Membranes, Ami C. Yang-Neyerlin, Samantha Medina, Kelly M. Meek, Derek J. Strasser, Cheng He, Daniel M. Knauss, Mustain E William, Svitlana Pylypenko, Bryan S. Pivovar

Faculty Publications

A series of spirocyclic copolymer membranes with varying ion exchange capacities (IECs) were investigated to probe the impact of polymer properties on in situ fuel cell performance and stability. In-situ electrochemical tests and post-mortem electron microscopy analysis of cross-sectioned membrane electrode assemblies (MEAs) have been combined with voltage loss breakdown analysis to evaluate the performance and degradation of different MEAs, and to probe the catalyst morphology and electrode structure at different stages of operation. Voltage loss breakdown results show that membrane degradation and kinetic losses played only a minor role in observed performance degradation and that performance losses were primarily …

Hybrid Lattice Boltzmann Agglomeration Method For Modeling Transport Phenomena In Polymer Electrolyte Membrane Fuel Cells, P. Satjaritanun, F. C. Cetinbas, S. Hirano, I. V. Zenyuk, R. K. Ahluwalia, Sirivatch Shimpalee

Faculty Publications

The Hybrid Lattice Boltzmann Agglomeration Method (HLBAM) was employed to model transport phenomena and electrochemical kinetics in the catalyst layer of a polymer electrolyte membrane fuel cell (PEMFC). This work showed the advantages of using a direct modeling-based HLBAM approach, which incorporates the detailed structure of catalyst layers from X-ray computed tomography as well as local transport variables related characteristics and effective properties from the hybrid catalyst microstructure. The local transport variables and effective properties from the hybrid catalyst model were used to simulate the electrochemical kinetics inside the detailed structure of the catalyst layer. HLBAM can predict the distribution …

Hydrothermal Synthesis And Structural Investigation Of A Crystalline Uranyl Borosilicate, Kristen A. Pace, Vladislav V. Klepov, Mark D. Smith, Travis Williams, Gregory Morrison, Jochen A. Lauterbach, Scott T. Misture, Hans Conrad Zur Loye

Faculty Publications

The relevance of multidimensional and porous crystalline materials to nuclear waste reme-diation and storage applications has motivated exploratory research focused on materials discovery of compounds, such as actinide mixed-oxoanion phases, which exhibit rich structural chemistry. The novel phase K1.8 Na1.2 [(UO2)BSi4 O12 ] has been synthesized using hydrothermal methods, rep-resenting the first example of a uranyl borosilicate. The three-dimensional structure crystallizes in the orthorhombic space group Cmce with lattice parameters a = 15.5471(19) Å, b = 14.3403(17) Å, c = 11.7315(15) Å, and V = 2615.5(6) Å3, and is composed of UO6 octahedra linked by [BSi4 O12 ]5− chains to …

Hydrothermal Synthesis And Structural Investigation Of A Crystalline Uranyl Borosilicate, Kristen A. Pace, Vladislav V. Klepov, Mark D. Smith, Travis Williams, Gregory Morrison, Jochen A. Lauterbach, Scott T. Misture, Hans Conrad Zur Loye

Faculty Publications

The relevance of multidimensional and porous crystalline materials to nuclear waste reme-diation and storage applications has motivated exploratory research focused on materials discovery of compounds, such as actinide mixed-oxoanion phases, which exhibit rich structural chemistry. The novel phase K1.8 Na1.2 [(UO2)BSi4 O12 ] has been synthesized using hydrothermal methods, rep-resenting the first example of a uranyl borosilicate. The three-dimensional structure crystallizes in the orthorhombic space group Cmce with lattice parameters a = 15.5471(19) Å, b = 14.3403(17) Å, c = 11.7315(15) Å, and V = 2615.5(6) Å3, and is composed of UO6 octahedra linked by [BSi4 O12 ]5− chains to …

Editors’ Choice-Power-Generating Electrochemical Co2 Scrubbing From Air Enabling Practical Aemfc Application, Yiwei Zheng, Garrett Huang, Mrinmay Mandal, John R. Varcoe, Paul A. Kohl, William E. Mustain

Faculty Publications

Anion exchange membrane fuel cells (AEMFCs) have been widely touted as a low-cost alternative to existing proton exchange membrane fuel cells. However, AEMFCs operating on air suffer from a severe performance penalty caused by carbonation from exposure to CO2. Many approaches to removing CO2 from the cathode inlet would consume valuable energy and complicate the systems-level balance-of-plant. Therefore, this work focuses on an electrochemical solution where CO2 removal would still generate power, but not expose an entire AEMFC stack to carbonation conditions. Such a system consists of two AEMFCs in series. The first AEMFC, which acts as an anion exchange …

Effect Of Membrane Properties On The Carbonation Of Anion Exchange Membrane Fuel Cells, Yiwei Zheng, Lyzmarie Nicole Irizarry, Noor Ui Hassan, Eric R. Williams, Morgan Stefik, Jacob M. Lamanna, Daniel S. Hussey, Mustain E William

Faculty Publications

Anion exchange membrane fuel cells (AEMFC) are potentially very low-cost replacements for proton exchange membrane fuel cells. However, AEMFCs suffer from one very serious drawback: significant performance loss when CO2 is present in the reacting oxidant gas (e.g., air) due to carbonation. Although the chemical mechanisms for how carbonation leads to voltage loss in operating AEMFCs are known, the way those mechanisms are affected by the properties of the anion exchange membrane (AEM) has not been elucidated. Therefore, this work studies AEMFC carbonation using numerous high-functioning AEMs from the literature and it was found that the ionic conductivity of the …

Kinetics Study Of The Hydrodeoxygenation Of Xylitol Over A ReoX-Pd/Ceo2 Catalyst, Blake Macqueen, Michael Royko, Bradie S. Crandall, Andreas Heyden, Yomaira J. Pagán-Torres, Jochen A. Lauterbach

Faculty Publications

In this study, we elucidate the reaction kinetics for the simultaneous hydrodeoxygenation of xylitol to 1,2-dideoxypentitol and 1,2,5-pentanetriol over a ReOx-Pd/CeO2 (2.0 weight% Re, 0.30 weight% Pd) catalyst. The reaction was determined to be a zero-order reaction with respect to xylitol. The activation energy was elucidated through an Arrhenius relationship as well as non-Arrhenius kinetics. The Arrhenius relationship was investigated at 150–170◦ C and a constant H2 pressure of 10 bar resulting in an activation energy of 48.7 ± 10.5 kJ/mol. The investigation of non-Arrhenius kinetics was conducted at 120–170◦ C and a sub-Arrhenius relation was elucidated with activation energy …

Kinetics Study Of The Hydrodeoxygenation Of Xylitol Over A ReoX-Pd/Ceo2 Catalyst, Blake Macqueen, Michael Royko, Bradie S. Crandall, Andreas Heyden, Yomaira J. Pagán-Torres, Jochen A. Lauterbach

Faculty Publications

In this study, we elucidate the reaction kinetics for the simultaneous hydrodeoxygenation of xylitol to 1,2-dideoxypentitol and 1,2,5-pentanetriol over a ReOx-Pd/CeO2 (2.0 weight% Re, 0.30 weight% Pd) catalyst. The reaction was determined to be a zero-order reaction with respect to xylitol. The activation energy was elucidated through an Arrhenius relationship as well as non-Arrhenius kinetics. The Arrhenius relationship was investigated at 150–170◦ C and a constant H2 pressure of 10 bar resulting in an activation energy of 48.7 ± 10.5 kJ/mol. The investigation of non-Arrhenius kinetics was conducted at 120–170◦ C and a sub-Arrhenius relation was elucidated with activation energy …

Bio-Oils From Vacuum Ablative Pyrolysis Of Torrefied Tobacco Residues, Nattawut Khuenkaeo, Blake Macqueen, Thossaporn Onsree, Sangu Daiya, Nakorn Tippayawong, Jochen A. Lauterbach

Faculty Publications

Fast pyrolysis, in combination with torrefaction pretreatment, was used to convert tobacco residues to value-added bio-fuels and chemicals. Tobacco plant residues were torrefied at 220, 260, and 300 °C, before being pyrolyzed at 450, 500, 550, and 600 °C in a rotating blade ablative reactor under vacuum conditions to test the effects on product yields. With torrefaction, tobacco residues thermally decomposed 20-25% w/w at low temperatures. Torrefaction and pyrolysis temperatures were found to markedly affect pyrolytic product yields of bio-chars and bio-oils, while having no effect on gas-phase products. Bio-oil yields exhibited a direct relation with pyrolysis temperature and an …

Bio-Oils From Vacuum Ablative Pyrolysis Of Torrefied Tobacco Residues, Nattawut Khuenkaeo, Blake Macqueen, Thossaporn Onsree, Sangu Daiya, Nakorn Tippayawong, Jochen A. Lauterbach

Faculty Publications

Fast pyrolysis, in combination with torrefaction pretreatment, was used to convert tobacco residues to value-added bio-fuels and chemicals. Tobacco plant residues were torrefied at 220, 260, and 300 °C, before being pyrolyzed at 450, 500, 550, and 600 °C in a rotating blade ablative reactor under vacuum conditions to test the effects on product yields. With torrefaction, tobacco residues thermally decomposed 20-25% w/w at low temperatures. Torrefaction and pyrolysis temperatures were found to markedly affect pyrolytic product yields of bio-chars and bio-oils, while having no effect on gas-phase products. Bio-oil yields exhibited a direct relation with pyrolysis temperature and an …

Material Discovery And High Throughput Exploration Of Ru Based Catalysts For Low Temperature Ammonia Decomposition, Katherine Mccullough, Pei-Hua Chiang, Juan D. Jimenez, Jochen A. Lauterbach

Faculty Publications

High throughput experimentation has the capability to generate massive, multidimensional datasets, allowing for the discovery of novel catalytic materials. Here, we show the synthesis and catalytic screening of over 100 unique Ru-Metal-K based bimetallic catalysts for low temperature ammonia decomposition, with a Ru loading between 1–3 wt% Ru and a fixed K loading of 12 wt% K, supported on γ-Al2O3. Bimetallic catalysts containing Sc, Sr, Hf, Y, Mg, Zr, Ta, or Ca in addition to Ru were found to have excellent ammonia decomposition activity when compared to state-of-the-art catalysts in literature. Furthermore, the Ru content could be reduced to 1 …