The ITML Development Process

Membrane Prototyping

Based on our matured-and-proven understanding of transport mechanisms, IMTL has devised unique theories and computerized models for membrane performance. In our prototyping process, these models, targeted to your performance specifications, quickly chart the approach and determine the probability of successful product development. With your added input and go-ahead we further design your product based on our judgement and models, as well as using a few carefully-selected check-test results. With a minimum of iterations, we produce a functional prototype. The fabrication equipment we use is similar to that needed in large-scale manufacturing. Finally, we test the prototype in our laboratory facilities ensuring that your performance specification is met.

IMTL prototype-fabrication methods are versatile, enabling prototyping of membranes/filters in various tubular shapes and sizes and out of an almost endless list of inorganic materials.

Beyond the speed and reliability of our membrane prototyping approach, the developed prototype embodies licensable, proven, low-cost scalable manufacturing technology.

Support Tube Fabrication and Sintering

For prototyping, IMTL selects materials for the tubular support that are compatible with the conditions (temperature and chemistry) of the process stream for the desired application. These support tubes, once formed, are sintered in one of IMTL's nine furnaces, which can accommodate samples up to eight feet long, temperatures up to 2200º C, and sintering atmospheres of air, inert gas, hydrogen, or vacuum. Sintering of a very broad range of materials results.

Porous Membrane Layering Techniques and Treatments

Considerations for membrane layering are

• a thin layer, by itself, is not strong enough to be self-supporting,
• a single porous material layer, with the proper pore size and with thickness enough to have handling strength, produces too large a pressure drop across the layer to permit efficient filtration, thus
• properly combined layers produce needed strength, overall pore size characteristics, and acceptable pressure drop at no sacrifice of permeance.

Single layer and multiple layer tubes are characterized in our Test Lab to verify proper pore size and permeance and to verify that the prototype is defect-free. Based on intermediate testing and modeling we employ iterative methods to guide the prototype development process to match desired performance specifications.

Test Lab

IMTL has a state-of-the-art testing and characterization laboratory with many one-of-a-kind pieces of test equipment required to fully evaluate membrane products throughout the development process…from initial material selection through prototype proof-of-function.

Candidate inorganic powder materials are evaluated using

• nitrogen adsorption surface area measurements,
• particle sizing by light scattering and particle morphology, and
• particle morphology and chemical composition analysis by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX).

Gas/liquid flow rates through the membrane must be accurately measured and characterized to effectively design a membrane, maximizing permeance and separation factors while minimizing pressure drop. IMTL has unparalleled test equipment and test capabilities to measure flow rates with a precision up to about 0.005%. Additionally, our measurement precision for mean pore size, pore size distribution, and surface area, are among the world’s best.

One of our special test capabilities is the measurement of adsorption performance of the membrane’s surface using different gas molecules. This testing may be conducted at a broad range of temperatures and operating pressures.

IMTL has the laboratory capability to demonstrate proof-of-function of completed prototypes under a broad range of real processing and operational conditions. Our state-of-the-art, high-precision, high-temperature mixed-gas-separation test system can be used to directly evaluate the performance of a membrane for separating one gas (or a group of gases) from a gas stream. Test temperatures to 600º C are permitted.

A partial list of other equipment used as detectors for custom-built separation test systems includes

• four gas chromatographs (one with mass spectrometer detector),
• a turbidity meter, and
• an FTIR spectrometer.

IMTL also has an Ultrapure Water system that is used for the preparation of filtration/purification test solutions and as a benchmark of evaluations of our water purification membranes.