Process and Reaction Engineering (PRE) Maria K. Burka --- Program Director 703-292-7030 email@example.com National Science Foundation
Program Overview Program supports research and educational projects related to: Interactions between chemical reactions and transport phenomena in reactive systems, and the use of this information in the design of complex chemical reactors (Reaction Engineering) a. Reactive processing of polymers (had increase in funding in this area in ‘06), ceramics, and thin films b. Electrochemical and photochemical processes of engineering significance or with commercial potential Design and optimization of complex chemical processes (Design) 3. Dynamic modeling and control of process systems and individual process units (Control) – had decreased funding in ‘06 Process and Reaction Engineering National Science Foundation
Reaction Engineering • Environmental issues – green chemistry • Ionic liquids for a variety of uses -- have tunable properties • Ionic electrolytes that separate electrodes and transport ions in electrochemical devices • Economic, “green” production in large quantities – in compressed or supercritical fluids • Use of high-temperature water as a reaction medium for organic chemical synthesis • Microreactors • Microchemical portable devices, e.g. fuel cells • Electro- and photo-chemical systems • Reactors used in microelectronics manufacturing: CVD, plasma reactors • Growth of ultra-thin films • High vacuum plasma-assisted CVD – reduced substrate temp, higher deposition rate, uniformity, etc. • Nano National Science Foundation
BCxNy HR-TEM P M e 3 H M e P 3 Ru(P) R u M e P H 3 SiO2 P M e 3 “Growth of Ultrathin Films”John G. EkerdtUniversity of Texas at Austin -- CBET-0553839 A team at UT is exploring the chemical vapor deposition growth of ultrathin amorphous metal films for applications in electronic materials, such as liner materials and metal electrodes, where crystalline grains have deleterious consequences as devices are scaled to ever smaller dimensions. Studies reveal alloying elements, such as phosphorus, stabilize amorphous ruthenium films. Simulations reveal nine- and ten-coordinate Ru-P polyhedra form during growth that cannot pack into the long-range order needed for crystal growth. Film properties are related to the phosphorus content and this content is adjustable using separate (dual) ruthenium and phosphorus sources. This precursor works above 250 ºC. PMe3 ligands desorb and/or undergo stepwise demethylation to incorporate zero-valent P into amorphous, metallic Ru-P films. Grazing angle X-ray diffraction and electron microscopy images of a 300 ºC film containing 15 atom % P.
Cathode (Pt on porous electrode) O2 from air H+ PMMA window Fuel / H+ Anode (Pt/Ru on graphite) Electrolyte & Fuel in . CAREER: Membraneless Micro Fuel CellsPaul Kenis – University of Illinois NSF CTS 05-47617 A membrane separates the anode and cathode compartments in most present-day fuel cell technologies (e.g. hydrogen fuel cells, direct methanol fuel cells). This membrane, however, is at the center of key performance limiting issues: crossover of fuel to the cathode causing cross-polarization, dry-out of the anode, and flooding of the cathode. Kenis et al.study membraneless fuel cells that utilize multistream laminar flow to provide the required compartmentalization. The lack of a membrane minimizes fuel crossover and water management issues. In addition, it allows for operation in alkaline media which enhances reaction kinetics at both electrodes. Multistream laminar flow In microfluidic channelsfluid flow is laminar. Two or more merging streamscontinue to flow in parallelwith slow diffusion as theonly mechanism of mixing(no turbulence). The electrolyte stream prevents fuel from reaching the cathode • Key features: • Fuel crossover minimized • No water management issues • Fuel flexible: formic acid, Methanol, ethanol, … • Media flexible: 40% performance jump in alkaline vs. acidic media J. Power Sources 2004,128, 54 J. Am. Chem. Soc. 2005, 127, 16758 Elec. Sol. State Lett. 2006, 9, A252
Chemical Process Control • Development of Fundamental Control Algorithms • Model predictive control • Robust, adaptive, etc. • Application areas • Spatial uniformity control in thin film deposition processes applicable to deposition systems where the substrate is rotated to improve uniformity National Science Foundation
Chemical Process Design • Development of Fundamental Design Methodology • Large-scale optimization strategies for design under uncertainty • Hierarchical design methods for rapidly estimating economically optimal operating policies for plants with recycle • Using concept of shortest separation lines for design of energy efficient multi-unit processes • Application Areas • Modeling and optimization of the pharmaceutical research and development and supply chain • Design of Tailor-made Molecules –> to Enterprises: • Solvents, polymers, etc. (ionic liquids of various sorts) • Rearrange model structures to interface process and molecular design problems through a set of target properties – incorporate economic, social, political and environmental conditions on the structure and design of chemical manufacturing facilities National Science Foundation
Systematic Mathematical Strategies for Stochastic Modeling and Uncertainty in Production Planning and SchedulingMarianthi Ierapetritou (PI) CBET-0625515 Rutgers University Program Objectives • Develop efficient parametric MILP methodology to generate the set of all alternative solutions in the face of uncertainty • Develop a robust optimization approach that addresses the multiobjective nature of the problem • Develop an efficient solution methodology for the multiobjective problem • Address realistic size planning and scheduling problems Stochastic Modeling – Application to Planning and Scheduling • Current Accomplishments • Efficient modeling of deterministic scheduling and planning problems • Parametric MILP for RHS uncertainty • Normal Boundary Intersection approach for the generation of pareto set of solutions that can address non-convex and even disjoint set of solutions • Approaches • Parametric optimization Enables the systematic identification of alternative solutions when no information is known about the uncertain parameters • Stochastic optimization Considers the alternative objectives in the face of uncertainty • Multiobjective optimization Enables the determination of the pareto set of alternative solutions
Reactive Polymer Processing • Paints, coatings, thin films, etc. • Living radical polymerization in inverse miniemulsions • Polymerize and crosslink natural phenolic compounds to form permanent antibiotic and anti-biofouling coatings • Other: • Use thiol-ene photopolymerization to produce high glass transition temperature and/or low shrinkage stress materials. • Use the speed of photopolymerization to predict and control the nanostructures produced in lyotropic liquid crystalline (LLC) systems • NIRT – Develop a prototype DNA-based machine capable of synthesizing organic polymers -- Nanomanufacturing National Science Foundation
OH OH COOH : Natural Phenolic Compounds R R Cardanol Anacardic acid Dong-Shik KimUniversity of Toledo (CBET-0626022) A team at the University of Toledo is developing new types of antimicrobial coating materials to prevent microbial growth on solid surfaces. Natural phenolic compounds are separated from biomass wastes, enzymatically polymerized, and cross-linked to form a permanent coating that has strong antimicrobial activities preventing the formation of biofilm on the solid surface. The coating can be used inbiomedical, health-care, and food applications. Anti-biofouling mechanisms are being studied focusing on the interaction between the phenolic coating and the cell’s sensing molecules that trigger biofilm formation. Enzymatic Polymerization & Coating P. fluorescens on the coated surface (×5,000). P. fluorescens on the uncoated surface (×5,000).
Nadrian C. SeemanNew York University CTS-0608889 -- NIRT A team at NYU and Caltech is using DNA-based nanomechanical devices to control polymer synthesis. One mode of control entails using RNA produced by transcriptional circuits to set the states of devices. The robust sequence-dependent PX-JX2 DNA device works well when controlled by DNA, but its unusual structure is not adequately responsive to RNA. A ‘cover strand’ strategy has been developed, wherein RNA strands (squiggly in the machine cycle diagram above) hybridize to and cover one or another activating segments on DNA strands that control the state of the PX-JX2 device. Thus, RNA strands can be used to control a DNA-based nanomechanical device, even though they do not bind directly to the device strands themselves.