Kevin Paul Mcevoy

Dielectric Loss Reduction of Ferroelectric Lead Magnesium Niobate-Lead Titanate Sound Projector Drivers

Improvement of the large signal dielectric loss of a commercial ferroelectirc lead magnesium niobate-lead titanate (PMN-PT) sound projector driver has been achieved without sacrificing other electromechanical properties. Length extensional resonators fabricated from the modified composition have been characterized for dielectric losses, 33-mode electromechanical coupling, and acoustic energy density under uniaxial compressive stress and large signal drive requirements for sound projectors. Selective doping and microstructural control have been used to achieve the desired properties.

Water-Gas-Shift Membrane Reactor for High-Pressure Hydrogen Production. A comprehensive project report (FY2010 - FY2012)

Idaho National Laboratory (INL), GE Global Research (GEGR), and Western Research Institute (WRI) have successfully produced hydrogen-selective membranes for water-gas-shift (WGS) modules that enable high-pressure hydrogen product streams. Several high performance (HP) polymer membranes were investigated for their gas separation performance under simulated (mixed gas) and actual syngas conditions. To enable optimal module performance, membranes with high hydrogen (H2) selectivity, permeance, and stability under WGS conditions are required. The team determined that the VTEC PI 80-051 and VTEC PI 1388 (polyimide from Richard Blaine International, Inc.) are prime candidates for the H2 gas separations at operating temperatures (~200°C). VTEC PI 80-051 was thoroughly analyzed for its H2 separations under syngas processing conditions using more-complex membrane configurations, such as tube modules and hollow fibers. These membrane formats have demonstrated that the selected VTEC membrane is capable of providing highly selective H2/CO2 separation (α = 7-9) and H2/CO separation (α = 40-80) in humidified syngas streams. In addition, the VTEC polymer membranes are resilient within the syngas environment (WRI coal gasification) at 200°C for over 1000 hours. The information within this report conveys current developments of VTEC PI 80-051 as an effective H2 gas separations membrane for high-temperature syngas streams.