Brown University School of Engineering

Joint Chemistry/Engineering Seminar

Wednesday, April 10, 2019

4:00pm - 5:00pm

School of Engineering

Geo-Chem Building, 351

In this joint Chemistry/Engineering seminar, Martin F. Haase, Assistant Professor of Chemical Engineering at Rowan University, will present a talk, “3D-Flow Analysis in Bijels Reconfigured for Interfacial Catalysis (3D-FABRIC). 
Abstract: Bicontinuous interfacially jammed emulsion gels (bijels) have been introduced over 10 years ago. Soon after their discovery, Prof. Mike Cates, Lucasian Professor of Mathematics, predicted their future use as continuously operated cross-flow reactors for chemical reactions between immiscible reactants. This potential yet remains to be demonstrated. Notoriously difficult to synthesize, few research groups worldwide succeed in bijel fabrication. Recently, we have introduced Solvent Transfer Induced Phase Separation (STrIPS), a significantly simplified technique for bijel generation. With STrIPS, the potentials of bijels as cross-flow microreactors are within reach. Our work has resulted in three research thrusts, outlined in the following: 3D-Flow Analysis in Bijels Reconfigured for Interfacial Catalysis: Bijels are stabilized with catalyst nanoparticles and assembled to continuously flow reactants and products in and out. The main questions to be answered are “What are the structure function relationships of STrIPS bijels governing mass transfer during catalytic cross-flow operation?”, “What is the influence of the interface and the mass transfer on the efficiency of the chemical process?”.
Hydrodynamics of bijel extrusion: To realize the emerging potentials of STrIPS bijels, means to measure and tailor the mechanical properties are needed. Our research aims to answer the question: “How are the viscoelastic properties of bijels determined by internal structure, surface tension, and adhesive particle interactions?” We investigate this question by applying controlled hydrodynamic shear stresses to characterize bijel rheology and assemble bijel fibers into multifunctional helices.
Nanocomposite hollow fiber membranes based on bijels. Polymerized STrIPS bijels can be employed as ultrafiltration membranes or as catalytic membrane reactors. However, the structure formation mechanisms of these new membranes are not yet understood. Our research will answer questions such as “Which organizing principles of liquid-liquid demixing and nanoparticle stabilization determine STrIPS membrane structures?”, and “How does separation and catalytic activity depend on membrane surface chemistry, morphology and hydrodynamics during filtration?”.
Our research introduces applications, but also addresses fundamental questions about nanoparticle assembly, phase separation, colloid stability, transport phenomena and fluid mechanics. Taken together, STrIPS bijels represent a fascinating new direction for research in the Soft Matter field.