AgendaTalk Details

Advanced Polymer Membranes for Molecular Separations in Organic Liquids

09:00 - 09:30 Level 0, between bld. 4 and 5

​​​​Membranes have had a huge impact in molecular separations in aqueous systems, especially desalination. It is generally accepted that 40-70% of capital and operating costs in chemical and pharmaceutical industries are dedicated to separations; and a substantial fraction of this cost is related to processing of organic liquids. Membrane technology has the potential to provide game changing alternatives to conventional concentration and purification technologies such as adsorption, chromatography, liquid extraction, evaporation and distillation, through Organic Solvent Nanofiltration (OSN) [1]. The membranes must offer resilience in organic environments, display attractive selectivities, and have good permeance. Ideally they should also be resistant to physical aging and fouling under use.
This presentation will focus on research into advanced membranes for OSN and their applications. Ultra-thin polyamide films (sub-10nm) have been formed by interfacial polymerisation and then used to fabricate composite membranes. These can be activated by a strong solvent, and have excellent permeance and high rejection [2]. It has been found that the aging of these composite membranes derives from properties of the support membrane rather than the thin film itself. Intrinsic microporosity can be introduced into the ultra-thin polymer films through selection of contorted monomers for interfacial polymerisation. These intrinsically microporous polymer nanofilms provide higher interconnectivity of pores and greater permeance than films obtained from planar monomer systems [3]. Further, new integrally skinned asymmetric membranes capable of filtration of solutions of DMF and other solvents at over 140oC have been developed by taking advantage of the properties of poly-ether-ether-ketone (PEEK) [4].
Finally, some applications and expected future developments of OSN will be introduced [5], and the potential for ultra-high permeance membranes to impact on actual molecular separation processes will be discussed, including the relative merits of selectivity, permeance and stability [6].

 

Figure 1 – Thin polyamide films 8nm thick showing smooth and crumpled structures [from 2]

References

  1. Marchetti P, Jimenez-Solomon, MF, Szekely, G and Livingston AG, Molecular Separation with Organic Solvent Nanofiltration – A Critical Review, Chemical Reviews, 114, 10735 – 10806 (2014)
  2. Karan S, Jiang Z, Livingston AG, Sub-10 nm polyamide films with ultrafast solvent transport for molecular separation, Science 348 pp 1347-1351 (2015) 
  3. Jimenez-Solomon, MF, Song, Q, Jelfs, KE, Munoz-Ibanez, M and Livingston, AG, Polymer nanofilms with enhanced microporosity by interfacial polymerization, Nature Materials Vol 15, Issue 7, pp.760-767 (2016)
  4. Da Silva Burgal J, Peeva L, Livingston AG Negligible aging in poly (ether-ether-ketone) membranes widens application range for organic solvent processing J.Mem.Sci (2017) 525 pp.48-56
  5. Peeva L, Da Silva Burgal J, Heckenast Z, Brazy F, Cazenave F. Livingston AG Continuous Consecutive Reactions by Inter-Reaction Solvent Exchange by Membranes Angewandte Chemie International Edition (2016) 55 pp.13576-13579
  6. Shi B, Marchetti P, Peshev D, Zhang S and Livingston AG Will ultra-high permeance membranes lead to ultra-efficient processes? Challenges for molecular separations in liquid systems J.Mem.Sci (2017) 520 pp.35-47