Laboratory and pilot evaluation of aquaporin-based forward osmosis membranes for rejection of micropollutants.

Aquaporin-based forward osmosis (AQP FO) membranes were applied both in laboratory- and pilot-scale for removing micropollutants from water. The effect of operating parameters (feed flow, draw flow, and transmembrane pressure) on the i) rejection of micropollutants, ii) water flux, iii) reverse salt flux, and iv) water recovery of the AQP FO membrane modules was studied. Among the 21 micropollutants spiked, only four compounds, atenolol, propranolol, metoprolol, and citalopram, permeated through the AQP FO membranes to an extent that they could be quantified in the draw solutions of both the laboratory and pilot systems. The rejection rates, based on the full mass balance calculations, were between 96.1% and 99.7%, and all the other 17 compounds showed rejection exceeding 90% on both systems. The pilot AQP FO system was further employed for six days to treat effluent from a membrane bioreactor (MBR) treating municipal wastewater. 35 micropollutants were investigated. 27 of these were identified and quantified in the MBR effluent. Minute fractions of gabapentin, benzotriazole, and metoprolol were detected passing through the AQP FO membranes into the draw side with a constant rejection of around 99.2%, 95.4%, and 99.9%. Almost all other micropollutants' minimum rejection rates exceeded 80%.

Challenges in Commercializing Biomimetic Membranes.

The discovery of selective water channel proteins-aquaporins-has prompted growing interest in using these proteins, as the building blocks for designing new types of membranes. However, as with any other new and potentially disruptive technology, barriers for successful market entry exist. One category includes customer-related barriers, which can be influenced to some extent. Another category includes market-technical-related barriers, which can be very difficult to overcome by an organization/company aiming at successfully introducing their innovation on the market-in particular if both the organization and the technology are at early stages. Often, one faces barriers from both these categories at the same time, which makes it necessary to gain insight of the particular market when introducing a new innovative product. In this review we present the basic concepts and discuss some of these barriers and challenges associated with introducing biomimetic aquaporin membranes. These include technical issues in membrane production and product testing. Then we discuss possible business models for introducing new technologies in general, followed by a presentation of beach-head market segments relevant for biomimetic aquaporin membranes.