Membrane technologies forward osmosis

To summarise, the development and remarkable success of commercial membrane processes for Uquid separations — RO, nanofiltration (NF), UF, and MF — would not have been possible without the discovery and subsequent development of high-flux, extremely thin (skinned) CA membranes by Srinivas Sourirajan and Sidney Loeb at UCLA, culminating in the development of TFC PA membranes by John Cadotte. Membrane technologies such as NF, PV and GS got the impetus from the work on RO in the 1950s and 1960s. These successes have led to the development of newer membrane processes such as membrane distillation (MD) and forward osmosis (FO). 

Reverse osmosis is widely used in the field of desalination technology. Reverse osmosis is displacing conventional thermal technologies, as well as other technologies such as membrane distillation, electrodialysis, and forward osmosis [91]. 

Forward Osmosis (FO) is an emerging membrane technology for water treatment that typically involves two steps ... 

Forward osmosis (FO) is an emerging membrane technology for water treatment and energy production. In an FO process, a semipermeable membrane is placed in between two solutions of different osmotic pressures. One is a less concentrated feed solution (FS) with lower osmotic pressure, while the other is a more concentrated draw solution (DS) with higher osmotic pressure. The water in the FS permeates through the membrane into the DS due to the osmotic pressure gradient across the membrane, but the solutes in the FS are selectively rejected by the membrane. 

Jin, X., Tang, C.Y., Gu, Y, She, Q. Qi, S. (2011) Boric acid permeation in forward osmosis membrane processes modeling, experiments, and implications. Environmental Science Technology, 45 (6), 2323-2330. 

Xie, M., Price, WE. Nghiem, L.D. (2012b) Rejection of pharmaceutically active compounds by forward osmosis role of solution pH and membrane orientation. Separation and Purification Technology, 93, 107-114. 

Figure 16.18 Flux performance of 2 commercially available RO membranes from GE Water (AG, CE) and a cellulose triacetate forward osmosis membranes from Hydration Technology Innovations (CTA). The draw solution used was a 6M ammonia-carbon dioxide solution and the feed solution was a 0.5M sodium chloride solution. The temperature of the test was 50°G Reprinted from REF16-B7. Tests were done in a custom built, crossflow, benchtop FO testing system.

M. Elimelech, Yale constructs forward osmosis desalination pilot plant. Membrane Technology 1 (2007) 7-8. 

Q. Yang, K.Y. Wang, T.S. Chung, Dual-layer hollow fibers with enhanced flux as novel forward osmosis membranes for water production. Environmental Science Technology... 

N.Y. Yip, A. Tirafeiri, W.A. Phillip, J.D. Schiffman, M. Elimelech, High performance thin-film composite forward osmosis membrane. Environmental Science Technology... 

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