Poster Session (4:45pm-6:30pm) 1) Materials and Cell Designs for - - PDF document

Poster Session (4:45pm-6:30pm)

1) Materials and Cell Designs for Bipolar Fuel Cells John M. Ahlfield / Prof. Paul A. Kohl

Bipolar membranes fuel cells utilizing both anion and cation conductive materials have several advantages compared to their purely acidic or alkaline counterparts due to improved water management and electrode kinetics. Material transport properties play an important role in determining viability of membrane and ionomer materials. Additionally, the material at the cation/anion junction is critical to device performance, as it must conduct ions to the interface in addition to mechanically binding the membranes. A series of devices using different interfacial materials has been fabricated for use in direct methanol and hydrogen fuel cells. These fuel cells were characterized by performance metrics and electrochemical impedance spectroscopy to determine specific areas for improvement in the bipolar devices. Operation under varying humidity was studied in order to understand water management necessary for bipolar fuel cells. This work will drive the future optimization of bipolar devices.

2) Calorimetric Heats of Adsorption Studies on Supported Amine Adsorbents for Post-Combustion CO2 Capture Mustafa A. Alkhabbaz / Prof. Christopher Jones

Supported amine adsorbents have emerged as promising materials for post-combustion CO2 capture from flue gas as well as from ambient air. However, the molecular basis for CO2 adsorption is not yet well developed, with most proposals for the adsorption mechanism based on only in-situ IR analyses. Understanding and quantifying the strength of the interactions between CO2 and amine sites is critical to the development of efficient amine adsorbents. In an effort to understand these interactions, heats of adsorption of CO2 on supported amine materials were experimentally measured using a customized calorimeter setup at the CO2 pressure range of interest to post-combustion CO2 capture and direct air capture (0-0.1 bar). A wide variety of amine adsorbents were tested to examine the effect of amine density and amine structures on heats of adsorption. The density/proximity of amines on the surface of the adsorbent is shown to influence the efficiency of adsorbents. Furthermore, favorable entropic factors in CO2 adsorption may play an important role in designing efficient amine adsorbents under air capture conditions.

3) Rabies vaccination in dogs using a dissolving microneedle patch Jaya Arya / Prof. Mark Prausnitz

Extended abstract – page 10

4) Prediction of Adsorption Properties in Zeolites Using Force Field Derived From DFT-CC Methods Rohan Awati / Prof. David Sholl

Molecular simulations like Grand Canonical Monte Carlo and Molecular Dynamics are widely used to predict adsorption isotherms, heat of adsorption, and diffusion of adsorbate molecules in porous materials like zeolites. Accuracy of such predictions depends mainly on how accurately Force field represents adsorbate-zeolite interaction. For such simulations, either off-the-shelf force fields (FF) or adsorption fitted force fields are used. Developing force fields from first principle methods is essential for it to be used as transferrable FF for various applications instead of developing a force field for a particular application. We have developed a transferrable force field for adsorbate-zeolite interaction using DFT-CC method. Here we first developed Coupled-Cluster (CC) corrections for adsorbate-zeolite using computational chemistry methods in Gaussian. DFT-CC method adds correction to DFT interaction energies to make it closer to

CCSD(T) energies which is considered to be accurate. We also tested other DFT methods such as PBE- D2,PBE-D3, and VDW-DF2 which overestimate adsorption isotherms while recently developed VDW- DF-CC method underestimate the adsorption isotherms in case of CH4.

5) Spontaneous Chiral Symmetry Breaking of Lyotropic Chromonic Liquid Crystals Confined in Cylindrical Capillaries Rui Chang / Prof. Mohan Srinivasarao and Prof. Elsa Reichmanis

Chiral symmetry breaking is crucially important for many interesting phenomena in nature, especially the homochirality of biomolecules. We investigate the spontaneous chiral symmetry breaking with achiral nematic lyotropic chromonic liquid crystals (LCLCs) confined in cylindrical capillaries. With planar anchoring, we surprisingly observe double twist configuration instead of the expected axial configuration without any director deformation. The left and right-handed twists are separated by domain walls with intriguing disclinations. With homeotropic anchoring, the escape radial configuration evolves to a new form with an axial twist mediated with pure-escape domain walls separating opposite handedness. The stability

• f the spontaneous twist is contributed to the anisotropy of elasticity and the contribution of saddle-splay

elastic constant in the free energy. In addition, a new ground state, two line defects with double helical configuration, is observed for LCLCs in cylindrical capillary with homeotropic anchoring after aging.

6) Metal Organic Frameworks for Selective Adsorption of t-Butyl Mercaptan from Natural Gas Grace Chen / Prof. Christopher Jones and Prof. William Koros

Pipeline natural gas is typically odorized with ~10 ppm of sulfur-containing components such as mercaptans for ease of detection. Such odorants can be removed before burning in electricity generation gas turbines to prevent or limit turbine corrosion and increase turbine lifetime. Selective adsorption of these odorants

• nto solid materials is an attractive removal approach because of the ability to remove trace levels of sulfur

and to be operated at low temperatures, making it less energy intensive than other traditional sulfur removal

• methods. Adsorbent material selection is important for this approach, and a material with high sulfur

capacity, selectivity, and regenerability is desired for practical implementation of such an adsorption

• system. In this study, several metal organic framework materials are gravimetrically screened for mercaptan

adsorption capacity and evaluated against a benchmark material, zeolite NaY, with emphasis on cyclic regenerability, stability, and selectivity towards TBM over methane and other impurities.

7) Simulation of a Zeolite Membrane Reactor System for Propane Dehydrogenation Seung W. Choi / Prof. Christopher Jones

The use of membrane reactors provides interesting opportunities for enhancing the performance of equilibrium-limited reactions like propane dehydrogenation (PDH). In this work we apply a two dimensional non-isothermal membrane reactor model to characterize the relationships between membrane properties and reactor conditions such as heat supply and radial dispersion. We employ a newly updated

kinetic model for a chromia/alumina catalyst (based upon our experimental work), as well as our experimentally obtained membrane permeance data for two types of zeolite membranes: MFI and SAPO-

• 34. We calculate detailed temperature and concentration profiles and discuss their effects on the membrane

reactor performance. We also carry out dimensionless analysis and assess the range of dimensionless parameters (such as the radial Péclet number) that minimize deleterious effects of radial dispersion. We then expand our study to a PDH plant using our membrane reactor model combined with a customized ASPEN-FORTRAN simulation which also includes downstream separation processes.

8) Characterizing the Association of Poly(2-oxzazoline) Materials with Various Chemicals via the Flory-Huggins Theory: Molecular Dynamics Simulation Approach Ben Chun / Prof. David Sholl and Prof. Seung Soon Jang

The simulation study investigates the polymer-chemical (epoxy and diol) interactions based on the Flory- Huggins theory using full atomistic molecular dynamics (MD) simulation. The quantified data demonstrate the change of the interaction parameter,  , with respect to the water content change. For this, first, the monomers of poly(2-oxazoline) series, the side chains of which are distinctive from each other, are geometry-optimized using B3LYP and 6-31G** and then Mulliken population analysis is performed for atomic charges. Second, the system of homogeneous polymer blend with various chemical contents is

• constructed. By performing MD simulation, the enthalpy of mixing is calculated from the system to estimate

the interaction parameters and optimum amount of chemical content in each homopolymer blend.

chemical polymer mixing

RT H     

The obtained data will be compared to the experimental ones in order to validate our simulation method as well as force field. We believe this study provides a molecular-level understanding of association of polymer with water molecules for characterizing the macro-scale polymer complex in water phase.

9) POM as Catalyst for Valorization of Lignin to Produce Chemicals Xu Du / Prof. Yulin Deng

Lignin is the second main component of lignocellulosic biomass after cellulose. However, it always has been considered as low-quality and low-added-value materials. Nonetheless, with its rich aromatic structure and huge production, it has potential to be the major renewable aromatic chemicals resource. Polyoxometalates (POMs) are a class of promising catalysts which can not only convert the lignin into chemicals and CO2, but also easily be regenerated by oxygen in aqueous solution. It is important to control the reaction conditions to produce useful chemicals, because lignin can ultimately be oxidized to CO2 and

• rganic acid such as formic acid. Vanillin has the potential to be the product. We need further researches

to separate and purify the products and increase the yield by optimizing the conditions.

10) Structure-property relationship for gas transport property of polymeric and carbon molecular sieve membranes of four novel 6FDA based polyimide polymers Shilu Fu / Prof. William J. Koros

This study considers separation performance of carbon molecular sieve (CMS) membranes formed by pyrolysis of four novel polyimide precursors referred to as 6FDA/DETDA, 6FDA:BPDA(1:1)/DETDA, 6FDA/DETDA:DABA(3:2) and 6FDA/1,5-ND:ODA(1:1). Separation performance of polymer precursor films formed from these polymers was examined using pure gases CO2, CH4, O2 and N2; a relationship between gas permeability and polymer fractional free volume (FFV) is reported. The pyrolyzed polymer precursor films to create dense CMS membranes produced separation performance that significantly exceeded the polymer precursor performance in all cases. The 6FDA/DETDA:DABA(3:2) derived CMS membranes showed the highest permeability and offered the greatest practical potential among the various

• precursors. Separation performance of the CMS membranes was studied as a function of time, with storage

under vacuum between tests to assess physical aging. For practical applications, continuous active feed of mixed gas 50% CO2/50% CH4 was shown to effectively suppress physical aging in 6FDA/DETDA:DABA(3:2) CMS membrane.

11) Selective Solid-Liquid-Vapor (SLV) Etching of Semiconductor Nanowires Ho Yee Hui / Prof. Michael Filler

The synthesis of complex, functional objects, at any length scale, requires the synergistic combination of additive, subtractive, and patterning “process” steps. Tremendous effort has been devoted to the additive (i.e., bottom-up) processing of nanoscale structures, but their directed subtraction and patterning remain largely

• unexplored. Here, we demonstrate a new process for the former – the selective removal of atoms from

semiconductor nanowires. 2,3-butanedione selectively extracts Ge atoms from the eutectic catalyst droplet, which results in undersaturation and dissolution of Ge from the solid nanowire. Experiments as a function of substrate temperature, etchant flow rate, and nanowire diameter support a solid-liquid-vapor (SLV) mechanism. A model of the process with reaction at the liquid-vapor interface as the rate limiting step is consistent with our

• experiments. These findings show how subtractive techniques can tune the structure of semiconductor nanowires

and also indicate a new route to enable atomically abrupt dopant profiles and heterointerfaces.

12) High performance barrier coating by 3D printed cellulose nanocrystal composites Vincent C. Li / Prof. H. Qi and Prof. Yulin Deng

Petroleum based plastics are major polymers used in paper barrier coating. However, these materials are unsustainable and non-renewable. Instead, cellulose nanocrystals, which can be extracted from the cell wall

• f trees and plants, offer a more sustainable and greener alternative. Recent studies showed that cellulose

nanocrystals-polymer composite materials exhibit unique properties that can be exploited to form barriers films, flexible displays, platforms for printable electronics, and many other cellulose based paper products. Nevertheless, it remains to be a major challenge to not only find compatible nanocrystals-curable resins

composite, but also design a facile and scalable approach for the fabrication of these composite materials into functional structures. The primary objective of this work is to explore possible properties from various composite formulations, and study the strength and weakness of different printing methods. We introduced silver nanoparticles and carboxylic acid functionalized Multi-walled-Carbon nanotubes (MWCNTs) into various resins, and then utilized inkjet and 3D printing techniques to print functional structures. We also studied the effects of substrate surface roughness to the morphology and connectivity of the printed layers. This work will lay the foundations for enabling future applications such as high barrier surface coating by 3D printed cellulose nanocrystal composites.

13) Evaluation of Esterification and Transesterification Reactions for Propylene Glycol Methyl Ether Acetate in Reactive Chromatography Systems Jungmin Oh / Prof. Yoshiaki Kawajiri and Prof. Andreas Bommarius

Reactive chromatography is a process that combines reaction and separation in a single unit that leads to a greater process performance and productivity. This process is especially advantageous when the reaction is equilibrium limited, and the in-situ separation of product shifts the equilibrium in the direction of conversion increase. This study focuses on the catalytic synthesis of propylene glycol methyl ether acetate through two separate types of reactions: transesterification and esterification. Both reactions are equilibrium limited, where conversion can be increased by applying the principle of reactive chromatography. Esterification is performed with an acidic catalyst, AMBERLYSTTM 15, which has high activity and

• stability. Transesterification is performed with a basic catalyst, AMBERLITE™ IRA-904, which shows

high activity at low temperatures. The benefits of each reaction are discussed with comparisons throughout the study. The chromatographic reactors were optimized for each reaction and esterification and transesterification were compared for the synthesis of the ester in terms of productivity and efficiency.

14) Microneedle Patches for Point-of-Care Diagnostics Pradnya Samant / Prof. Mark Prausnitz

Extended abstract – page 27

15) Particle Stabilized Equilibrium Droplet Structures in Three Phase Liquid Systems Abiola Shitta / Prof. Sven Behrens

Particle stabilized emulsion droplets have been studied for over a century, but gained renewed interest recently as templates and precursors for functionalized microcapsules that leverage modern methods of particle synthesis and surface modification. According to the current understanding of Pickering emulsions, homogeneous particles can stabilize emulsions only kinetically, not thermodynamically. They can, however, change the thermodynamic equilibrium state of oil droplets at a water-air interface and even mediate complete spreading of an otherwise non-wetting liquid, as shown by Goedel et al. Here we show that Goedel’s description of “particle-assisted wetting” can be extended to mixtures of 3 mutually immiscible liquids and predict the particle-mediated shift in equilibrium. For liquids with appropriate interfacial tensions and particles with suitable wettability, particle adsorption at the liquid interfaces results in the thermodynamic stabilization of double emulsion droplets. We report theoretical predictions along with experimental evidence for the existence of thermodynamically stabilized Pickering double emulsions.

16) CO2 Capture from Air by Temperature Swing Adsorption via Direct Steam Stripping Using MOF Film Coated inside Monolith Anshuman Sinha / Prof. Matthew Realff and Prof. Yoshiaki Kawajiri

The concentration of CO2 in the Earth’s atmosphere is currently 400 ppm, which is estimated to go beyond 500 ppm in a few decades. Many Direct Air Capture systems have already been proposed; however economic constraint remains a significant obstacle for most of the processes. In this study, we have used direct steam stripping to enable Temperature Swing Adsorption. Metal Organic Frameworks are used as adsorbent film, coated inside monolith surface, to capture CO2 from air. We have modeled mass and energy inventories for cyclic TSA process, to provide feedback to the material synthesis activities on performance

• enhancement. We have compared water adsorption vs water condensation during desorption step to analyze

the efficiency of the system. The ultimate objective is to perform optimization studies on the complete TSA model in order to make the Direct Air Capture system economically robust.

17) Model based design and optimization of a continuous, simultaneous reactor-separator process Shan Tie / Prof. Yoshiaki Kawajiri and Prof. Andreas Bommarius

Global energy demands have necessitated process intensification to transform chemical plants into safer, energy-efficient, and environmentally sustainable processes. One strategy, the simulated moving bed reactor (SMBR), is a better alternative to conventional sequential batch reactor and separator operations. SMBR improves separation resolution, increases productivity, and reduces solvent consumption. Despite these benefits, the complexity in SMBR modeling and design is challenging for industrial implementation. Past work to optimize the SMBR were focused on single-objective optimization or used heuristic based algorithms This work will demonstrate a practical and deterministic model-based approach to optimize a multiple objective SMBR operation for an industrially relevant production process. The model identifies the necessary operating parameters that are then implemented experimentally. The results will show that the model is predictive of SMBR experimental results and the model’s accuracy can be improved when the experimental SMBR data is used to recalculate the parameter values of the SMBR model.

18) Capillary Foams: A Small Amount of Immiscible Secondary Fluid Makes a Big Difference Yi Zhang / Prof. Sven Behrens and Prof. Carson Meredith

Liquid foams are familiar from beer, frothed milk, or bubble baths; foams in general also play important roles in oil recovery, lightweight packaging, and insulation. Here a new class of foams is reported, obtained by frothing a suspension of colloidal particles in the presence of a small amount of an immiscible secondary

• liquid. A unique aspect of these foams, termed capillary foams, is the particle-mediated spreading of the

minority liquid around the gas bubbles. The resulting mixed particle/liquid coating can stabilize bubbles against coalescence even when the particles alone cannot. The coated bubbles are further immobilized by entrapment in a network of excess particles connected by bridges of the minority liquid. Capillary foams were prepared with a diverse set of particle/liquid combinations to demonstrate the generality of the

• phenomenon. The observed foam stability correlates with the particle affinity for the liquid interface formed

by spreading the minority liquid at the bubble surface.

19) Lignin/polymer Composites via Miniemulsion Polymerization through Chemically Modified Lignin Zhe Zhang / Prof. Yulin Deng and Prof. Donggang Yao

Lignin is the second most abundant biomass substance, usually around 20-40% of annual plant due to different species. However, most lignin is burnt directly for heat without any further modification, which is challenging due to the specific issues of lignin, including the difficulty in separation and purification processes, structure nonuniqueness and solubility difficulty in both water and organic phases. The specific purpose of this research is to develop high-valued applications for lignin. Particularly, miniemulsion polymerization is chosen to make polymer-lignin nanocomposites; before polymerization, lignin modification with different chemicals is needed in order to enhance its solubility in organic monomers. Thereafter, physical and mechanical properties will be tested, which are expected to be the same or improved compared with pure polymer particles.