NU 2017-081
Inventors
Kazi Sadman
Qifeng Wang
Kenneth Shull*
Short Description
A high-throughput method for the preparation of highly stable membrane films and foams for water and organic solvent purification.
Background
Polymer films are used as filtration membranes in a diverse set of applications, such as in gas separation, reverse osmosis, nano-, ultra-, and micro-filtration due to their flexibility, controllable properties, and low cost. However, industrial scale applications such as membrane filtration of solvents during semiconductor manufacturing and waste water are limited due to low throughput manufacturing processes. In addition, such polymer films tend to have a high-cost burden associated with removing and replacing membranes that have lost function due to fouling.
Abstract
Northwestern researchers have developed a high-throughput manufacturing method for producing highly porous polyelectrolyte complex (PEC) membranes and foams with tunable pore sizes, for ultra- and micro-filtration purposes. The high stability of PECs in several industrially relevant solvents makes PEC membranes ideal for both water and organic solvent purification. This technology condenses multiple processing steps into a single high throughput procedure using commonly implemented polymer manufacturing techniques. Currently, the fabrication of PEC films requires serial deposition of a layer of positively charged polymer followed by a negatively charged polymer. In contrast, this new method reveals that under the appropriate conditions these steps can be combined to allow for organization of the polymer in solution. This organized solution can then be deposited in a single step to produce a film (see figure). PEC foams comprised of a viscous polymer solution can be easily shaped into forms such as discs and cylinders offering increased versatility. Both PEC membranes and foams can be post-functionalized using surface treatments for e.g. anti-fouling and allow a single platform to be re-used for a range of filtration applications. Moreover, the membranes can be easily dissolved using a concentrated salt solution and redeposited, reducing the cost of removing and replacing the filtration membrane.
Applications
Advantages
Publications
Sadman K, Wang Q, Chen SH, Delgado DE, Shull KR (2017) pH-Controlled Electrochemical Deposition of Polyelectrolyte Complex Films. Langmuir. 33: 1834-1844.
IP Status
A US patent and PCT applications have been filed.