Presentation Session I: March 29th, 2012—12:30pm An Inorganic Nanotube/Polymer Composite Membrane Platform for Molecular Separations Presenter: Dun-Yen Kang / Advisors: Sankar Nair and Christopher W. Jones Nanotubes possess intriguing mass transport properties, but have so far not been successfully integrated into an economical molecular separation device. We are working towards creation of an advanced molecular separation platform by incorporating inorganic (e.g. single-walled metal oxide) nanotubes into polymeric membranes. In this talk, I will first describe the fabrication and characterization of defect-free nanotube/polymer composite membranes, containing aluminosilicate single-walled nanotubes embedded in a poly (vinyl alcohol) matrix. I then will describe the permeation behavior of alcohols and water through these membranes by experimental and molecular simulation techniques. Finally, I will introduce a mass transport model with specific applicability to composite membrane systems containing tubular fillers, and use it to analyze the membrane permeation properties. I will show that our new model provides analytical guidance for the fabrication and understanding of membranes containing nanotubular fillers. Ester Crosslinked Hollow Fiber Membranes for Natural Gas Separations Presenter: Canghai Ma / Advisor: William J. Koros Compared to conventional amine absorption processes to separate CO2 from natural gas, membrane separation technology can offer lower capital cost and higher energy efficiency. Unfortunately at high CO2 partial pressures, swelling-induced plasticization of polymeric membranes causes low CO2/CH4 separation efficiency and loss of CH4. Covalent ester-crosslinking has been proven effective to increase the plasticization resistance by controlling the segmental chain mobility in the polymer; however, only relatively thick selective layers and lower CO2 permeance have been reported to date. This study will focus on extending the success of crosslinking to more productive hollow fibers with enhanced plasticization resistance. The skin layer thickness of hollow fibers was first optimized by engineering the fabrication process based on a 6FDA-based polyimide. Ester-crosslinking was then utilized to stabilize the highest productivity hollow fibers against plasticization. The fibers were further probed by using aggressive feed conditions including aromatic contaminants to ensure they were viable in practical natural gas feed streams. Prediction-Correction Method for Optimization of Simulated Moving Bed Chromatography Presenter: Jason Bentley / Advisor: Yoshiaki Kawajiri Simulated moving bed chromatography (SMB) is a powerful tool for the production-scale separation of complex mixtures. The current practice of process development for a new system relies on an expensive set of experiments, model predictions, and heuristic optimization approaches. This practice tends to take much effort and materials to develop an SMB model, and yet the model mismatch may remain. In this study, we develop the prediction-correction method that resolves model mismatch and optimizes an SMB process simultaneously following a systematic procedure. To resolve model mismatch we fit our model simulation to SMB experimental data during process startup using nonlinear parameter estimation. Then we perform model-based optimization to determine the operating conditions that are expected to maximize productivity while maintaining strict purity constraints. In a case study, the prediction-correction method has been shown to be successful in optimizing the separation of nucleosides uridine and guanosine.

Plasma-fluorination of Epitaxial Graphene Presenter: Sonam D. Sherpa / Advisor: Dennis W. Hess Fluorination of graphene has emerged as an attractive approach toward manipulating its physical, chemical, and electronic properties. To this end, we have demonstrated the viability of sulfur hexafluoride plasmas to fluorinate graphene as a safer alternative to the commonly reported techniques of fluorination that include exposures to fluorine and xenon difluoride gas. Incorporation of fluorine moieties on graphene after SF6 plasma-treatment was confirmed by X-ray photoelectron spectroscopy. Modifications in the valence band states of graphene after plasma-treatment were characterized by ultra-violet photoelectron spectroscopy. Increase in work function of plasma-treated graphene demonstrates the ability of plasma-assisted fluorination to modify the electron emission characteristics of graphene. Raman spectroscopy reveals that the majority of carbon atoms in graphene retain their sp2 hybridization after the plasma-treatment. Low energy electron diffraction (LEED) studies indicate the graphene lattice remains intact after the plasma-treatment. Advanced Photosensitive Polynorbornene Dielectric Presenter: Mehrsa Raeiszadeh / Advisor: Paul A. Kohl Polymer dielectrics are widely used in the microelectronics and micro-electro-mechanical system (MEMS) industry for several applications including interlevel dielectrics, passivating layers, and encapsulants. Photosensitive polynorbornene (PNB)-based dielectrics are of special interest because they have easy processing, excellent dielectric properties, and high mechanical strength. Additives can be included in the polymer mixture to improve the sensitivity and photodefinability. In this study, an approach to creating higher sensitivity formulations with superior photodefinition properties without non-crosslinking additives has been found. Tetraphenylol ethane glycidyl ether (TPEGE), a tetra-functional epoxy based crosslinker, was used to enhance Avatrel 8000P, an already photosensitive, PNB-based polymer dielectric. Additionally, the processing conditions for the PNB-based dielectric were optimized and their effect on the polymer properties was studied. The addition of TPEGE to Avatrel 8000P resulted in high contrast, high sensitivity, excellent adhesion, and the ability to make high-aspect-ratio features, making the polymer suitable for MEMS and microelectronics applications.

Presentation Session II: March 29th, 2012—2:25pm Molecular Synthesis, Characterization and Application of Oligo-thiophene-benzothiadiazole Based Low Bandgap D-A Copolymers Presenter: Boyi Fu / Advisor: Elsa Reichmanis Four oligo-thiophene benzothiadiazole π-conjugated donor-acceptor (D-A) copolymers and one oligomer were synthesized through incorporating the electron-deficient benzothiadiazole (BT) unit into the electron-rich thiophene chain. The oligomer, bisdodecylthiophene-dithieno-benzothiadiazole, BDTDTB, and the polymeric counterparts, poly(bisdodecylthiophene-dithieno-benzothiadiazole), PBDTDTB, and poly(quaterdodecylthiophene-dithieno-benzothiadiazole), PQDTDTB, were synthesized via Stille coupling; while poly(quaterdodecylthiophene-vinylene-dithieno-benzothiadiazole), PQDTVDTB, and poly(quaterdodecylthiophene-vinylene-didodecylthieno-benzothiadiazole), PQDTVDDTB, having vinylene linkages within the chain were prepared by HWE polymerization. These low bandgap copolymers (1.52~1.55 eV) have photon harvesting abilities approaching the NIR region, a property of significance for organic photovoltaic applications. PBDTDTB and PQDTDTB exhibited field effect hole mobilities up to 0.01 and 0.03 cm2V-1s -1, respectively.

Hybrid Zeolitic Imidazolate Frameworks: Controlling Framework Porosity and Functionality by Mixed-Linker Synthesis Presenter: Joshua A. Thompson / Advisors: Christopher W. Jones and Sankar Nair Zeolitic imidazolate frameworks (ZIFs) are a subclass of nanoporous metal-organic frameworks (MOFs) that exhibit zeolite-like structural topologies and have interesting molecular recognition properties such as molecular sieving and gate-opening effects associated with their pore apertures. This work investigates the synthesis and characterization of hybrid ZIFs with mixed linkers in the framework, thereby producing properties different from the parent frameworks (ZIF-8, ZIF-90, and ZIF-7). NMR spectroscopy is used to show control over the relative amounts of the linkers included in the framework. In the case of ZIF-8-90 hybrids, the cubic structure of the parent frameworks is continuously maintained, whereas in the ZIF-7-8 hybrids there is a transition from a cubic to a rhombohedral structure. Nitrogen physisorption reveals that the hybrid materials exhibit substantial changes in gate-opening phenomena, either occurring at continuously tunable partial pressures of N2 (ZIF-8-90 hybrids) or loss of gate-opening effects to yield more rigid frameworks (ZIF-7-8 hybrids). Mixed Oxide Supports Derived From Layered Metal Hydroxides to Reduce Methanol Selectivity in the Catalytic Synthesis of Higher Alcohols over Potassium-Promoted Molybdenum Sulfide Catalysts Presenter: Michael R. Morrill / Advisor: Christopher W. Jones Molybdenum sulfide, a well-known hydrodesulphurization catalyst, is being increasingly investigated as a catalyst for conversion of synthesis gas to higher alcohols. Here it is demonstrated that potassium promoted MoS2 catalysts supported on basic, mixed metal oxides derived from decomposed, synthetic hydrotalcites convert syngas into higher alcohols with reduced methanol and increased n-propanol selectivity relative to bulk molybdenum sulfide or conventionally supported molybdenum sulfide catalysts (activated carbon, basic sepiolite clay, or alumina). This advantage may be attributed to the basic, mesoporous nature of the mixed metal oxide support. X-ray adsorption spectroscopy shows that before sulfidation, the molybdenum oxide domains on the supported catalyst are highly dispersed. Treatment of this oxide catalyst at 723 K in 20% hydrogen sulfide in hydrogen results in the formation of molybdenum sulfide moieties that in turn provide a favorable environment for higher alcohol formation. Internal Surface Functionalization of Pure-Silica Zeolite MFI Crystals with Amines, Aromatics, and Amino-Alcohols Presenter: Mohamad H. Kassaee / Advisors: Sankar Nair and David S. Sholl Organic functionalization of zeolites has attracted much attention because it can significantly widen the range of their applications. Internal surface functionalization of zeolite can be accomplished by covalently binding organic groups within the micropore structure. The functionalized zeolite would then become an organic-inorganic hybrid with a potential for a diverse range of new applications including selective separation agent. We report preparation and characterization of pure-silica MFI zeolite crystals and films whose internal pore structures are functionalized with aliphatic alcohols (1-butanol, 1-hexanol), an aromatic alcohol (benzenemethanol), amino-alcohols (3-amino-1-propanol, aminoethyl ethanolamine), and amines (1-propanamine, and 1,3-propanediamine). 13C NMR and TGA investigation suggest functional groups are chemically bound to internal pore sites. 29Si NMR studies suggest that functional group loading is strongly dependent on the concentration of internal silanol defects. The adsorption isotherms of CO2, CH4 and N2 for the functionalized crystal samples and their CO2/CH4 and CO2/N2 selectivity are reported and discussed.

Batch Depolymerization and Hydrodeoxygenation of Switchgrass Lignin using Formic Acid and Pt/C Presenter: Weiyin Xu / Advisors: Christopher W. Jones and Pradeep K. Agrawal Second generation biofuels derived from lignocellulosic biomass have the potential to be fossil fuel substitutes that generate less CO2 emissions without competing with the demand for food stocks, unlike first generation biofuels. Recent studies showed that using formic acid in an alcohol medium to process lignin, a component of biomass, yielded depolymerized and hydrodeoxygenated lignin. In this study, we explore the combination of formic acid in ethanol and a 20 wt% Pt/C catalyst to improve the fuel properties of switchgrass lignin via depolymerization and catalytic hydrodeoxygenation. The properties of the reaction products were investigated after the reaction was carried out at 350 °C with varying reaction times of 1 hour, 4 hours, 8 hours and 20 hours. After the reaction, the lignin products have improved H/C and O/C molar ratios, lower molecular weight, an increased fraction with lower boiling points and a yield of up to 21 wt% of identified monomeric aromatic species. Polyamide-Imide Membranes for Aggressive Natural Gas Purification Presenter: Justin Vaughn / Advisor: William. J. Koros Polymer membrane based natural gas separations are challenged by the presence of CO2 and H2S, which cause membrane swelling and performance declines. H2S presents additional separation challenges due to its highly condensable nature and fundamentally contrasting transport behavior to CO2. The bulk of the research done in natural gas separations has focused on CO2, thus the transport behavior of H2S is not well defined. This work characterizes a novel class of pure polymer membrane materials possessing intrinsically high plasticization resistance towards CO2 and H2S removal from natural gas. The effect of structure modification is studied in terms of fractional free volume, polymer-polymer and polymer-penetrant interactions, as well as pure gas transport parameters. Separation performance is characterized at pressures up to 1000 psia using mixtures containing Toluene/CO2 and H2S/CO2 in order to simulate well-head conditions. These tests reveal polyamide-imides as a potential alternative to covalent crosslinking for aggressive gas separations.

Presentation Session III: March 30th, 2012—9:00am Biopolymer Translocation Through Solid-State Nanopore Devices: a Langevin Dynamics Study Presenter: Christopher M. Edmonds / Advisor: Sankar Nair Small nanopores (1 – 10 nm diameter) constructed in solid-state membranes have shown promise as next-generation biopolymer analysis devices offering both high resolution and throughput. In this work, we use Langevin Dynamics simulations to investigate the translocation of DNA-like biopolymers through nanopores as a function of the nanopore dimensions, driving voltage, and biopolymer length. Based upon the simulation results, we elucidate the scaling laws of the translocation time of both “long” and “short” biopolymers as a function of their length and of the applied voltage. We discuss the physical implications of these scaling laws and their relationship to theoretical models and experimental data. This information can be used in designing algorithms for operating nanopore devices and to interpret the experimental data more reliably. Temperature Responsive Polymers: Optimization of Linear and Branched poly(N-isopropylacrylamide) for Biological Applications Presenter: Kai Chang / Advisor: Lakeshia J. Taite Poly(N-isopropylacrylamide) (pNIPAAm) is one of the most well-studied temperature responsive polymers and has been extensively studied for possible biological applications. For most of these applications, pNIPAAm is necessarily modified to provide the desired temperature response.

Nevertheless, most current processes ignore many of the subtle, yet powerful ways to control the temperature response resulting in sub-optimal configurations. We have identified and optimized several key drivers that can be combined in various ways to change the temperature response of linear pNIPAAm for biological transition temperatures. These drivers include end-group manipulation, molecular weight control, and tacticity control. Furthermore, we incorporated these principles and findings into a hyperbranching system. The results indicate another independent variable that can be leveraged in tuning the temperature response: degree of branching. With these tools, it is possible to exert significant control over the temperature response independent of or in conjunction with traditional copolymerization methods. Associated Lattice-Fluid Equation of State Model for CO2-Polymer System Presenter: Mohammad Hossain / Advisor: Amyn S. Teja We derive a new Lattice-Fluid Equation of State for associating systems by incorporating complex formation in the Sanchez-Lacombe lattice-fluid partition function. We show that the new equation can be used to correlate the solubility of carbon dioxide in several homo and co-polymers over a wide range of temperatures and pressures, and that the extent of swelling in these polymers by CO2 can be predicted using parameters obtained from the solubility correlation. We also demonstrate that one of the parameters of the equation of state that describes specific interactions between the polymer and carbon dioxide can be quantified using in situ attenuated total reflection fourier transform infrared (ATR FTIR) spectroscopy. The calculation of this parameter via NVT molecular dynamics simulation is also described. The new equation of state offers the potential of phase behavior over a wide range of pressures and temperatures prediction using swelling measurements at low pressures. Amine-Functionalized Metal-Organic Framework Synthesis Kinetics and Crystallization Process Design Presenter: Paul M. Schoenecker / Advisor: Krista S. Walton Metal-organic framework (MOF) synthesis and characterization has increased exponentially in recent years. Due in part to the nearly infinite set of structure possibilities, MOFs exhibit potential for a plethora of applications including gas separation and storage, catalysis, drug delivery, as well as thin films. Amine-functionalized MOFs including IRMOF-3, DMOF-1-NH2, and UiO-66-NH2 are of particular importance for many applications including selective gas adsorption and NO delivery. With the benefits of amine-functionalized MOFs in mind, we examine the scalability of UiO-66-NH2 synthesis techniques within sealed vessels as well as the potential to implement a continuous-flow reactor. Characterization of the products is accomplished by examining the product yield, crystallinity, and porosity via analytical weighing, pXRD, and BET modeling of the N2 adsorption at 77 K, respectively. We propose that similar iterations of this approach will prove successful for scale-up of other MOF syntheses.

Presentation Session IV: March 30th, 2012—10:35am Engineering of Double Pickering Emulsion-Templated hybrid Colloidosomes and Fundamentals of Emulsifications with Nano-Particles Presenter: Hongzhi Wang / Advisor: Sven H. Behrens Colloidosomes are semipermeable microcapsules with external shell formed by colloidal particles, providing promising technique for encapsulations with controllable permeability, mechanical properties and bio-compatibility. Our work explores double Pickering emulsion, also known as particle stabilized emulsions, as precursors to synthesize composite colloidosomes for triggered and sustainable release control with envisioned applications in flexographic printing and biomedical aspects. To generate such colloidosomes, a prerequisite is the controlled formation and stabilization of Pickering emulsions.

Unfortunately, our current fundamental understanding of Pickering emulsions is still far from satisfactory and often fails to predict reliably the stability and the type of Pickering emulsions. We therefore focus on understanding the fundamentals of Pickering emulsions by researching emulsifications with polymeric nano-particles. Our study suggests two widely neglected electrostatic effects in Pickering emulsions, one is the effect of image charge repulsion on the emulsion formation, and the second is the effect of dipole-interaction on the preferred emulsion type. The obtained new insights will benefit not only our design of colloidosomes but realms relevant to Pickering emulsions. Carbon Molecular Sieve Membranes for N2/CH4 Separation Presenter: Xue Ning / Advisor: William J. Koros Many natural gas reserves are contaminated by high content of nitrogen which has to be removed to meet pipeline specification. Membrane gas separation is an economic alternative to upgrade natural gas compared to traditional separation technologies. Membrane separation for N2/CH4 was not previously widely studied because of the small size difference between N2 and CH4 and competing effects of diffusion and sorption, which lead to unattractive permselectivity. The best performing traditional polymer membrane materials can only provide N2/CH4 selectivity around 3 due to the broad distribution of segmental motions. Carbon Molecular Sieve (CMS) Membranes overcome this problem by providing rigid structure and distinctive bimodal pore size distribution. Different pyrolysis conditions of Matrimid® and resultant separation performance of CMS films were studied in this work. It was shown that N2/CH4 selectivity was improved with increased pyrolysis temperature, and a N2/CH4 selectivity ~7.5 was achieved. Detailed studies showed that N2/CH4 selectivity resulted from a high N2/CH4 diffusion selectivity which overcame the unfavorable N2/CH4 sorption selectivity. Hofmeister Effects on a Yeast Prion Protein Presenter: Jonathan Rubin / Advisors: Andreas S. Bommarius, Sven H. Behrens and Yury O. Chernoff Prion proteins are capable of converting from their soluble, biologically-functional forms into highly ordered, fibrous aggregates, called amyloids. This conversion is associated with certain neurodegenerative conditions, such as Alzheimer's disease. Protein misfolding is strongly influenced by ion-specific solvent effects, known as Hofmeister effects. Using a yeast prion protein, we tested the influence of a host of sodium salts on aggregation kinetics and investigated the aggregates that were formed. Aggregation kinetics was starkly different between the two main groups of salts (chaotropes and kosmotropes). We investigated structural differences between the amyloids by tested their thermostability, infectivity and imaged them using EM. In the presence of kosmotropes, aggregates were fast forming, least thermostable, most infectious and appeared smallest and least orders when imaged. The opposite was true of aggregates formed in chaotropes. This work shows the profound effect of solvents and ion-specific effects on aggregation and disease. Dynamics of Amine-oxide Hybrid Adsorbents for Post-Combustion CO2 Capture Presenter: Praveen Bollini / Advisor: Christopher W. Jones Amine-oxide hybrids are rapidly emerging as alternatives to physisorbants like zeolites and carbons for post-combustion CO2 capture. Although numerous amine adsorbents with high CO2 adsorption capacities have been synthesized, the dynamics of adsorption onto this class of materials remains relatively unexplored. The two kinetic studies reported in the literature thus far use isothermal adsorption models to investigate adsorption dynamics, necessitating the use of empirical modifications to fundamental models to obtain reasonable fits with experimental data. In this study, we use coupled heat and mass transfer models, resulting in a more fundamentally sound framework with which to investigate dynamic processes in aminosilica packed beds. In addition to demonstrating the importance

of taking into account heat effects when studying this class of materials, we also gained insights into the diffusion process occurring in these porous materials, which was found to be highly heterogeneous, especially for adsorbents with high amine loadings. Cationic Polyelectrolytes Decrease Gelatinization Temperature of Cornstarch Presenter: Sandeep Mora / Advisor: Sujit Banerjee Cationic polyelectrolytes such as c-PAM and poly-DADMAC decrease the gelatinization temperature of cornstarch granules. Enzymatic hydrolysis of cornstarch is, therefore, more efficient in the presence of the polymers. Viscosity profiles of various combinations of the cornstarch/enzyme/polymer system will be presented as will corresponding glucose and Brix values. A mechanism for the effect of the polymer will be proposed and discussed with reference to previous work on polyelectrolyte assisted hydrolysis of bleached cellulosic fiber.

Poster Presentations #1 Poster Title: Positive-Tone, Aqueous-Developable, Polynorbornene Dielectrics: Lithographic

and Dissolution Properties

Authors: Brennen K. Mueller, Edmund Elce, Angelica M. Grillo, Paul A. Kohl

Abstract:

A positive-tone, aqueous base soluble, polynorbornene (PNB) dielectric formulation has been developed.

The photolithographic solubility switching mechanism is based on diazonaphthoquinone (DNQ)

inhibition of polynorbornene resin functionalized with pendent hexafluoroisopropanol and carboxylic acid

substituents. The optical contrast (at 365 nm) was found to be 2.3. The maximum height-to-width aspect

ratio of developed line and space features was 3:2. The sensitivity, D100, of a formulation containing 20

pphr of DNQ photoactive compound (PAC) was calculated to be 408 mJ/cm2. The effects of the DNQ

molecule structure on miscibility and dissolution of the photosensitive films in aqueous base developer

were studied. The effect of the monomer composition of the PNB polymer on the dissolution rate of the

formulated PNB resin was evaluated. A unique dissolution and swelling behavior was observed. The

effect is attributed to a copolymer synthesized with two monomers each of which is susceptible to

deprotonation in aqueous base. FTIR measurements showed that the pure PNBHFI has a small

percentage of free hydroxyl groups which did not change appreciably by the addition of DNQ to the

mixture.

#2 High Performance ZIF/Polyimide Mixed Matrix Membrane for Separation of Propylene and

Propane Presenter: Chen Zhang / Advisor: William J. Koros #3 Computational Studies of Biopolymer Translocation through Silicon Nitride Nanopore Devices

Presenter: Christopher M. Edmonds / Advisor: Sankar Nair #4 Emerging single-walled aluminosilicate nanotubes for novel separation platforms

Presenter: Dun-Yen Kang / Advisors: Sankar Nair and Christopher W. Jones #5 Shear-Induced Demixing in Polymeric Membrane Dopes

Presenter: Emily Peterson / Advisor: Victor Breedveld

#6 Poster Title: Impact of Functional Groups on the Adsorption Properties of the High-Stability

MOF: UiO-66

Authors: Gregory E. Cmarik, Krista Walton

Abstract:

A family of materials which are isostructural to the highly stable MOF, UiO-66, were tested for

their adsorption properties with respect to carbon dioxide, methane, nitrogen and water vapor.

Four functional groups, chosen for their polarity, hydrophobic nature, and basic nature, were

introduced into the pore space by varying the linker used in synthesis. Pure component

isotherms were measured and heat of adsorption was calculated for each material-gas pair using

the Clausius-Clapeyron equation. The results show the adsorption performance is enhanced by

the polar nitro, amino and methoxy functional groups. Heat of adsorption at low loading is

increased from 26 to 32 kJ/mol of CO2 adsorbed upon adding polar functional groups. Also, all

members of the UiO-66 family adsorb water with the naphthyl and methoxy functionalities

showing the most hydrophobic character. The results show the methoxy functional group as a

candidate for further study in CO2 adsorption applications in humid systems.

.

#7 Engineering of Double Pickering Emulsion-Templated Hybrid Colloidosomes and Fundamentals

of Emulsifications with Nano-Particles Presenter: Hongzhi Wang / Advisor: Sven H. Behrens

#8 Poster Title: Rational Engineering of Nanowire Superstructures

Authors: Ildar Musin, Michael A. Filler

Abstract:

Semiconductor nanowire engineering provides a promising route to achieve novel

nanoarchitectured materials with applications in photon harvesting, photonics, and

thermoelectrics. In order to enable the appropriate function for a particular application, control of

atomic and nanoscale structural details (e.g. lattice, orientation, faceting) is critical. We

demonstrate the ability to engineer nanowire structure by tuning chemistry either at the

nucleation point or on the sidewall, thus enabling the rational fabrication of complex

superstructures for the first time. Specifically, we have gained the chemical understanding

necessary to select crystal growth direction and create kinking superstructures with well-defined

angles and segment lengths. Additionally, by controlling sidewall chemistry, we demonstrate

how “molecular resists” either allow or prevent conformal deposition, and leverage this

knowledge to fabricate diameter-modulated nanowires with user-defined periodicity. These new

synthetic strategies comprise a much needed toolbox for the precision engineering of nanoscale

structures and materials properties #9 Prediction-Correction Method for Optimization of Simulated Moving Bed Chromatography

Presenter: Jason Bentley / Advisor: Yoshiaki Kawajiri

#10 Poster Title: Interactions of Biomass Molecules with Heterogeneous Catalysts in Aqueous and

Vacuum Environments

Authors: John R. Copeland, Carsten Sievers

Abstract:

Aqueous phase catalytic processes for biomass conversion are promising because many biomass-

derived compounds readily dissolve in water and because water is an abundant, green solvent.

The current study aims to elucidate the fundamental interactions of biomass derived oxygenates

with catalysts and supports. Specifically, the interactions of ethylene glycol, 1,2-propanediol,

1,3-propanediol, glycerol, glucose and sorbitol with -Al2O3 and 5 wt% Pt on -Al2O3 were

studied. Transmission IR was used to investigate surface interactions between the various

biomass derived oxygenates and -Al2O3. This analysis showed interactions with specific surface

hydroxyls and alkoxide bond formation as a function of co-adsorbed water. Interactions between

glycerol, glucose and sorbitol dissolved in water and 5 wt% Pt on -Al2O3 were studied using a

flow ATR-IR setup. This study showed that the formation kinetics of hydrogen and carbon

monoxide on the Pt surface is dependent on the pretreatment, and on the carbon chain length of

the reactant. #11 Poster Title: Characterizing the Response of a Newly Constructed Thermodenuder to

Laboratory-generated Aerosol

Authors: Kate M. Cerully (1), Molly McLaughlin (2), David Tanner (2), James R. Hite, Jr. (2),

Richard H. Moore (1), Athanasios Nenes (1, 2)

(1) Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA

(2) Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA

Abstract:

A thermodenuder (TD) is an instrument that exposes a stream of particles to a known

temperature profile for a given amount of time. Based on the volatilized amount of mass

(characterized by the decrease in particle size) unique insights on the volatility distribution and

kinetics of compounds in aerosol can be determined. This study presents the results from the

design and construction of a TD that exposes particles from ambient to 110oC for residence times

between approximately 24 and 80 s. The instrument is fully characterized experimentally for

centerline temperature, particle transmission losses, and the response function for particles of

known dry size and composition.

We present experimental and modeling results of the thermodenuder response function to size-

selected (40-120 nm) aerosol composed of one to three atmospherically-relevant compounds of

variable proportions and for a range of temperatures (30-110oC). The compounds considered are

dicarboxylic acid and ammonium sulfate particles. The dicarboxylic acids used (e.g., glutaric

acid, succinic acid, and azelaic acid) span a wide range of volatilities as their saturation mass

concentrations range from approximately 0.1 to 100 μg m-3

.1 The experimental data are evaluated

against the predictions of a new, comprehensive numerical model of the instrument; the model

predicts the velocity, pressure, temperature, and aerosol size (as a function of its volatility

distribution) by numerically solving the Navier-Stokes equations coupled with the conservation

of energy and mass of evaporating particles.

1Donahue et al., Atmos. Chem. Phys. Discuss., 2010

#12 Do Hydrogen Isotope Effects in Metal Hydrides Matter?

Presenter: Kelly Nicholson / Advisor: David S. Sholl #13 Effect of Shear and Elongation on Polymer Morphology in Hollow Fibber Spinning

Presenter: Kyung Hee Oh / Advisor: Victor Breedveld #14 Development Of A Novel Tool For Glycomics And Purification By Utilization of a R. solanacearum

lectin Presenter: Lindsay Arnold / Advisor: Rachel Chen

#15 Olefin/Paraffin Separation Using Robust Carbon Molecular Sieve Membranes

Presenter: Liren Xu / Advisor: William J. Koros #16 Poster Title: Surface Modification of Inorganic Molecular Sieves for Use in Mixed Matrix

Membranes (MMM)

Authors: Megan E. Lydon, Christopher Jones, Sankar

Abstract:

Gas separations (such as purification of natural gas) play an important role in emerging clean

energy technologies. Membranes offer lower energy consumption and fabrication costs than the

currently prevalent, thermally-driven methods. Mixed matrix membranes (MMMs), containing a

polymer bulk phase with a dispersed inorganic phase, offer enhanced membrane performance by

incorporating the selectivity of crystalline, molecular-sieving materials (e.g., zeolites) with the

processability and low cost of polymer membranes.

Several methods of zeolite surface modification have recently been developed by

depositing MgOxHy nanostructures that enhance compatibility at the polymer/molecular sieve

interface. In this work, zeolites functionalized by the multiple methods are characterized in detail

to demonstrate the differences in nanowhisker coverage, size, and surface area produced by each

method. These nanostructure properties are correlated with the membrane performance and

mechanical properties of the MMM to assess the relative suitability of each functionalization

method for use in gas separation membrane fabrication.

#17 Internal Surface Functionalization of Pure-Silica Zeolite MFI Crystals with Amines, Aromatics, and

Amino-Alcohols Presenter: Mohamad H. Kassaee / Advisors: Sankar Nair and David S. Sholl

#18 Poster Title: Controlling Silicon Nanowire Growth Direction via Surface Chemistry

Authors: Nae Chul Shin, Michael. A. Filler

Abstract:

Semiconductor nanowires offer exciting opportunities to fabricate high performance devices for

energy conversion, photonics, and quantum computation. The precise control of crystal structure

and geometry is required to achieve a desired behavior, especially in highly confined nanoscale

systems. Unfortunately, a fundamental understanding of the surface chemistry that controls

surface energetics is currently lacking, despite its critical importance for robust synthesis.

Although hydrogen is prevalent during the hydride-based vapor-liquid-solid growth of

semiconductor nanowires, its role is largely unknown. To this end, we systematically studied the

effect of hydrogen during the growth of Si nanowires and confirmed its influence on crystal

growth direction, catalyst ripening, and sidewall faceting for the first time. In-situ transmission

infrared (IR) spectroscopy was used to identify the presence and bonding of hydrogen on Si

nanowires as a function of growth conditions. Si nanowires were grown via a two-step process:

(1) brief nucleation at high temperature (550oC) and low pressure (5x10

-5 Torr) followed by (2)

elongation under different conditions (400 – 500oC, 5x10

-5 – 5x10

-3 Torr). Vertically-oriented

epitaxial Si nanowires with uniform densities, diameters, and lengths were obtained with this

method. In-situ IR data recorded in real-time reveals the evolution of surface Si-H stretching

modes near 2090 cm-1

and 2075 cm-1

as a function of growth conditions. Our data indicates that

surface-bound hydrogen is responsible for changes in crystal orientation even when nanowire

diameter remains constant. More specifically, the surface energy of the nuclei-vapor interface

near the triple-phase-boundary is stabilized by hydrogen, which leads to a {111} sidewall facet

and growth in the [112] direction. This work demonstrates the important role that hydrogen plays

in the growth of semiconductor nanowires at multiple length scales. The extensive use of hydride

chemistries for most group IV and III-V semiconductor nanowire syntheses suggests significant

implications for a myriad of systems.

#19 Metal-Organic Framework Synthesis and Crystallization Process Design Presenter: Paul M. Schoenecker / Advisor: Krista S. Walton

#20 An Absorption Refrigeration System Using Non-Toxic and Non-Volatile Ionic Liquid and

Hydrofluorocarbon Working Fluids Presenter: Sarah Kim / Advisor: Paul A. Kohl

#21 Poster Title: Ab initio study of proton diffusion in Potassium Tantalate perovskites

Authors: Sung Gu Kang, David S. Sholl

Abstract:

KTaO3 (KTO) is a useful prototypical perovskite for examining the mechanisms of proton

transport. Previously, Gomez et al. reported DFT calculations describing proton hopping in

defect-free KTO (Gomez et al., J. Chem. Phys., 126, 194701, (2007)). We have used DFT

calculations to extend that work in two directions, namely understanding isotope effects in low

and high temperature proton transport and the role of native point defects in KTO. At cryogenic

temperatures, quantum tunneling plays an appreciable role in the net hopping of protons in KTO.

At the elevated temperature characteristic of applications involving proton conducting

perovskites, tunneling is negligible but zero point energy effects still lead to non-negligible

isotope effects for H+, D

+, and T

+. We used DFT to characterize the populations of relevant point

defects in KTO as a function of experimental conditions, and to examine the migration of proton

near and in combination with these defects. This information gives useful insight into the overall

transport rates of protons through KTO under a variety of external environments. We also

assessed the overall diffusivity of protons in KTO at the range of oxygen vacancy concentrations

by performing Kinetic Monte Carlo (KMC) simulations.

#22 Poster Title: Novel Solvents vs Monoethanolamine for CO2 Capture: a Comparison

Authors: Swetha Sivaswamy, Ryan Hart, Kyle Flack, Amy Rohan, Jackson Switzer, Emily Nixon,

Amber Rumple, Farhana Momin, Elizabeth Biddinger, Manish Talreja, Pamela Pollet, Charles Liotta and

Charles Eckert

Abstract:

Chemical absorption of CO2 with aqueous amine solutions such as monoethanolamine (MEA) is

the most mature technology for the capture of CO2 from the flue gas of coal fired power plants.

We have developed novel silyl-amine molecules for CO2 capture at the Eckert-Liotta group at

Georgia Tech. These novel solvents are neutral molecules which react with CO2 to form an ionic

liquid, which then can further absorbs additional CO2 by a physisorption mechanism.

Subsequently, modest elevations in temperature reverse the reaction and, in principle, yield pure

CO2 for sequestration. In this poster, I will compare silyl-amines that we have developed to

MEA in terms of important process parameters. The iterative procedure used for the design of

molecules, based on structure-property relationships, will be outlined. Our efforts to control and

mitigate the viscosity of the ionic liquids will also be presented.

#23 High-Solids, Mixed-Matrix Hollow Fiber Sorbents for CO2 Capture

Presenter: Vinod Babu Pandian Babu/ Advisor: William J. Koros #24 Carbon Molecular Sieve Membranes for N2/CH4 Separation

Presenter: Xue Ning / Advisor: William J. Koros #25 Poster Title: Functionalization of BTC and its Effect on Properties of Copper-Based Metal-

Organic Frameworks

Authors: Yang Cai, Krista Walton

Abstract:

Porous metal-organic frameworks (MOFs) have attracted considerable attention in recent years,

due to potential applications of these novel porous materials in gas storage, heterogeneous

catalysis, selective guest adsorption, and sensor technology. Compared with conventional

microporous materials, MOFs with pore sizes and chemical functionalities can be designed by

modifying the metal group or organic linkers. There is an outstanding challenge in the synthesis

of crystalline nanoporous materials to systematically design pore size and functionality of metal

organic framework. Here, porous structures in which pore size and functionality could be varied

systematically have been designed by changing the functional groups of ligands. Highly porous

metal coordination polymers [Cu3(MBTC)2(H2O)3]n (where MBTC is methyl-1,3,5-

benzenetricarboxylate) and [Cu3(EBTC)2(H2O)3]n (where EBTC is ethyl-1,3,5-

benzenetricarboxylate) have been solvothermally synthesized in mixed solvents of H2O and

ethanol. They both have two different [Cu2(O2CR)4] units (where R is an aromatic ring), which

create the same three-dimensional framework with open metal sites and high surface area. The

pore size and adsorption properties are altered by introduction of the organic groups –CH3 and –

C2H5. Both of them exhibit much lower adsorption of water than HKUST-1 due to the

hydrophobic functional groups. CuMBTC showed higher adsorption of CO2 and CH4 than

HKUST-1 at relative low pressure. CuEBTC has higher CO2 and CH4 adsorption ability than

CuMBTC due to its flexibility, even though it has lower surface area.

#26 Cationic polymer aided acceleration of starch hydrolysis for the production of Biofuels

Presenter: Kendra Maxwell / Advisor: Sujit Banerjee

#27 Fabrication of Optofluidic Sensor Using Polynorbornene Polymers for Single Molecule Detection Presenter: Mehrsa Raeiszadeh / Advisor: Paul A. Kohl