Nanoparticle Micromixers

Why is this technology needed?

A growing need within the emerging nanotechnology industry is monodisperse nanoparticles (NPs). Existing batch mixing technology has difficulty controlling concentration and temperature gradients during NP growth reactions, which leads to wide residence time distributions, varying growth rates and polydisperse NP size distributions. Further, laminar flow micromixing technology faces difficulty controlling residence time distributions due to nonuniform velocity distributions.

How does this technology address the need?

The MBI has designed and fabricated many different micromixing solutions for nanoparticle synthesis. Numbered up interdigital micromixing designs are capable of handling liter per minute flow rates while managing flow uniformity during mixing. Reverse oscillatory flow (ROF) micromixing systems (see Figures 1 and 2) are capable of fast mixing with minimal dead volume, ease of fabrication and assemblability for cleaning at liter per minute flow rates. Microchannel emulsifiers are able to create large quantities of emulsions, which are used to control crystal growth reaction conditions in producing various types of nanomaterials.

How is MBI contributing to the solution?

The ONAMI Safer Nanomaterials and Nanomanufacturing Initiative is currently involved in a multi-year program to investigate greener and safer methods of producing nanomaterials for industrial application. The MBI has a multi-year effort targeted on investigating crystal growth phenomena within microchannels yielding new designs for micromixers and microemulsifiers based on computational fluid dynamic analyses and experimental validation (Figure 3).

The Oregon Process Innovation Center (OPIC) is a unique facility within the MBI for developing benchtop chemistries and demonstrating pilot-scale chemical process development and in-process characterization. Examples of unique capabilities developed within OPIC are the patent-pending microreactor-assisted nanomaterial deposition (MANDTM) technologies, which are at the core of a strategy for displacing expensive vapor-phase process steps within PV manufacturing.

Collaborators:

• Chih-hung Chang, Director of OPIC
• Brian K. Paul
• Dan Palo
• Todd Miller

For additional information . . .

To learn more about this technology, please contact Chih-hung Chang.