Benjamin A. Wilhite

Highly Size‐Selective Ionically Crosslinked Multilayer Polymer Films for Light Gas Separation

Exceptionally high hydrogen permselectivity, exceeding that of any polymeric or porous inorganic systems, is achieved using an ionically crosslinked multilayer polymer thin film.

Super hydrogen and helium barrier with polyelectolyte nanobrick wall thin film.

In an effort to impart light gas (i.e., H2 and He) barrier to polymer substrates, thin films of polyethylenimine (PEI), poly(acrylic acid) (PAA), and montmorrilonite (MMT) clay are deposited via layer-by-layer (LbL) assembly. A five quadlayer (122 nm) coating deposited on 51 μm polystyrene is shown to lower both hydrogen and helium permeability three orders of magnitude against bare polystyrene, demonstrating better performance than thick-laminated ethylene vinyl-alcohol (EVOH) copolymer film and even metallized polyolefin/polyester film. These excellent barrier properties are attributed to a nanobrick wall structure. This highly flexible coating represents the first demonstration of an LbL deposited film with low hydrogen and helium permeability and is an ideal candidate for several packaging and protection applications.

An all-metallic microburner for a millimeter-scale thermophotovoltaic generator

Thermophotovoltaics (TPVs) is the conversion of heat to electricity via the thermal emission of photons and their subsequent absorption and conversion to electricity by infrared photovoltaic cells. One of the key challenges is designing a robust microburner with an integrated selective emitter—and having the system operate at 1000°C for thousands of hours. Previous attempts at TPV system demonstrations tend to be large, inefficient, and have limited lifetimes. Here we present a novel all metallic microburner design and experimental results in the context of a proposed small, robust, and efficient TPV generator. Fabricated entirely by machining and welding, the microburner is comprised of a serpentine channel in a 20 × 20 mm slab of Inconel with inlet and outlet capillaries that double as mechanical supports. The microburner has a thermal power input of 50 to 100 W and reaches temperatures of 700 to 1100°C. The metallic microburner is robust under high temperature operation and a 2D tantalum photonic crystal can be attached by welding for high fuel-to-electricity conversion efficiency. We characterized the microburners exhaust composition and temperature distribution which matched well with CFD simulations. We operated the microburner at 60 W of input power (reaching about 1000°C) for 135 hours before it failed.

Multi-scale approaches for gas-to-liquids process intensification: CFD modeling, process synthesis, and global optimization

Abstract This paper presents a multi-scale framework for the intensification of small scale gas-to-liquids (GTL) processes. As the process intensification tool, a radial microchannel reactor is used to facilitate the catalytic steam reforming of methane. Due to the endothermicity of this reaction, a microchannel reactor serves as a promising alternative because of its enhanced heat transfer characteristics. However, the underlying mathematical model for the microchannel reforming process is complex. Since our aim is to elucidate the optimal process topology from a plethora of alternatives through a global optimization framework, we built a surrogate mathematical model to bridge this gap. Through a rigorous model identification, parameter estimation, and cross-validation analysis we have developed an accurate mathematical model that can predict the microchannel reactor output within 0.43%. We then implemented this mathematical model into a process superstructure that considers several novel and competing process alternatives for the production of liquid fuels from natural gas. Across different case studies ranging from 500 to 5000 barrels per day of total production, we have observed that the microchannel process can improve break-even oil prices (BEOP) by as much as

Design of an annular microchannel reactor (AMR) for hydrogen and/or syngas production via methane steam reforming

10/bbl. Since the small scale GTL process aims to utilize stranded natural gas with almost zero value, a parametric analysis is performed to evaluate the BEOP at different feedstock prices. We have observed that the microchannel reforming alternative is the superior process at all the scales investigated when a natural gas price of

A theoretical comparison of multifunctional catalyst for sorption-enhanced reforming process

1/TSCF is considered. The topological findings suggest that process intensification through microchannel steam reforming is a viable approach to monetize stranded natural gas.