University of Colorado

University Technology Corporation

Chevron U.s.a. Inc.

National University of Singapore

University Patents, Inc.

William B Krantz

Alan R Greenberg

Julie Chabot

Krishniah Parimi

Marc E Voorhees

Paul W Todd

Harold J Trimble

David E Earls

Adrian Yeo

Seyed Saeid Hosseini

Elmira Kujundzic

Bruce A Nerad

Andrew E Neice

Guo Yong Chai

Leonard J Bond

Robert R Bilodeau

Roger J Elgas

A method for determination of pore-size distribution in a porous material called evapo porometry (EP) is capable of determining pore sizes from approximately the nanometer scale up to the micron scale. EP determines the pore size based on the evaporative mass loss at constant temperature from porous materials that have been pre-saturated with either a wetting or non-wetting volatile liquid. The saturated porous material is placed in an appropriate test cell on a conventional microbalance to measure liquid mass loss at a constant temperature as a function of time. The mass-loss rate is then related to the pore-size distribution. The microbalance permits measuring the mass as a function of time. The slope of the mass versus time curve is the evaporation rate. The evaporation rate is related to the vapor pressure at the interface between the liquid in the porous material and the ambient gas phase. The vapor pressure in turn is related to the pore diameter.

Determination of pore size in porous materials by evaporative mass loss

An apparatus and method for controlling the pore structure of thin polymeric sheets, such as porous membranes and thin films, during solvent casting or interfacial polymerization. The invention may be used to reduce or eliminate macrovoid pore defects from solvent-cast or interfacially polymerized polymeric membranes used in a variety of separations or controlled release tasks or to create a desired pore structure in porous thin films, such as may be used in breathable garments, surgical dressings, and screen printing. A nonuniform electric field is generated at one or more locations in proximity to a liquid film in which a desired pore structure is to be formed. Due to the difference in dielectric constant between the liquid within the pores and that in the surrounding liquid, the electric field causes an attractive or repulsive force on the evolving pores.

Apparatus and method for controlling pore size in polymeric membranes and thin films

The invention comprises an OCR catalyst reactor which includes passive spheres and catalyst particles having substantially the same size and separated on opposite sides of a distributor cone by a screen. The use of passive spheres of substantially the same size to the catalyst particles provides for a more uniform distribution of the gas liquid reactants charged into the reactor vessel. The screen is configured such that it provides a separation of the catalyst and the passive spheres while being sized to prevent plugging.

Balanced flow resistance OCR distributor cone

The fouling state of a polymeric membrane within the high pressure housing of a spiral wound or a hollow fiber membrane module is determined. An ultra sonic transducer positioned with its emitting face in physical engagement with the outer surface of the housing is pulse energized by a pulser/receiver device. A membrane echo signal is detected by a receiver of the pulser/receiver device. A reference echo signal indicative of a fouled or an unfouled state of the membrane is compared to the echo signal to determine the membrane fouling state. The echo to reference comparing step can be based upon comparing amplitude domain signals, comparing time-domain signals, comparing combinations of amplitude domain and time-domain signals, and comparing transformations of amplitude domain and time-domain signals. A clean or a fouled reference echo can be provided from a clean or a fouled membrane and then stored for use during a liquid separation process, or a clean reference echo signal can be obtained on-line from a second transducer whose echo signal is derived from an area of the membrane known to remain relatively unfouled during the liquid separation process, or a clean or fouled reference echo signal can be provided for later use during a cleaning process or during a liquid separation process. Multiple transducers and a switching network can sample the fouling state at different positions within the membrane module.

Method and apparatus for determining the state of fouling/cleaning of

A medical device and method for affecting mass transfer between blood and a fluid. In one application, this mass transfer is an oxygenation of the blood. Generally, a membrane which separates the blood and fluid is moved in a predetermined manner and in a direction which is substantially parallel to that of the primary direction of the flow to augment the mass transfer efficiency/rate. Importantly, this movement of the membrane is relative to the blood mass transfer boundary layer which steepens or increases the oxygen concentration gradient and decreases the thickness of the blood mass transfer boundary layer and thereby improves upon the mass transfer efficiency/rate of oxygen into the blood.

Blood treatment device with moving membrane

A reverse osmosis membrane process or hybrid membrane - complementary separator process for producing enriched product or waste streams from concentrated and dilute feed streams for both solvent/solvent and solute/solvent systems is described.

Continuous countercurrent membrane column for the separation of

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Boulder, CO, United States of America

William B Krantz