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  • Journal article
    Marchetti P, Mechelhoff M, Livingston A, 2015,

    Tunable-porosity membranes from discrete nanoparticles

    , Scientific Reports, Vol: 5, ISSN: 2045-2322

    Thin film composite membranes were prepared through a facile single-step wire-wound rod coating procedure in which internally crosslinked poly(styrene-co-butadiene) polymer nanoparticles self-assembled to form a thin film on a hydrophilic ultrafiltration support. This nanoparticle film provided a defect-free separation layer 130–150 nm thick, which was highly permeable and able to withstand aggressive pH conditions beyond the range of available commercial membranes. The nanoparticles were found to coalesce to form a rubbery film when heated above their glass transition temperature (Tg). The retention properties of the novel membrane were strongly affected by charge repulsion, due to the negative charge of the hydroxyl functionalized nanoparticles. Porosity was tuned by annealing the membranes at different temperatures, below and above the nanoparticle Tg. This enabled fabrication of membranes with varying performance. Nanofiltration properties were achieved with a molecular weight cut-off below 500 g mol⁻¹ and a low fouling tendency. Interestingly, after annealing above Tg, memory of the interstitial spaces between the nanoparticles persisted. This memory led to significant water permeance, in marked contrast to the almost impermeable films cast from a solution of the same polymer.
  • Journal article
    Shi B, Marchetti P, Peshev D, Zhang S, Livingston Aet al., 2015,

    Performance of spiral-wound membrane modules in organic solvent nanofiltration – Fluid dynamics and mass transfer characteristics

    , Journal of Membrane Science, Vol: 494, Pages: 8-24, ISSN: 1873-3123
  • Journal article
    Yeo BJL, Goh S, Zhang J, Livingston AG, Fane AGet al., 2015,

    Novel MBRs for the removal of organic priority pollutants from industrial wastewaters: a review

    , JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY, Vol: 90, Pages: 1949-1967, ISSN: 0268-2575
  • Journal article
    Mazlan NM, Peshev D, Livingston AG, 2015,

    Energy consumption for desalination - a comparison of forward osmosis with reverse osmosis, and the potential for perfect membranes

    , Desalination, Vol: 377, Pages: 138-151, ISSN: 0011-9164

    Reverse osmosis (RO) is now the most ubiquitous technology for desalination, with numerous seawater ROplants being built in water-stressed countries to complement existing water resources. Despite the developmentof highly permeable RO membranes, energy consumption remains a major contributor to total cost. Forward osmosis(FO) is receiving much attention as a potentially lower energy alternative to RO. However, the draw solution(DS) recovery step in FO requires significant energy consumption. The present study is a modellingapproach, simulating FO and RO desalination under various process conditions and process flow schemesusing the Aspen Plus environment. Results suggest that there is practically no difference in specific energy consumption(SEC) between standalone RO, and FO with nanofiltration (NF) DS recovery; this can be generalised forany pressure-driven membrane process used for the DS recovery stage in a hybrid FO process. Furthermore, evenif any or all of the membranes considered, FO, RO or NF, were perfect (i.e. had infinite permeance and 100%rejection), it would not change the SEC significantly. Hence, any advantage possessed by the FO with NF recoveryprocess derives from the lower fouling propensity of FO, which may reduce or eliminate the need for pretreatmentand chemical cleaning
  • Journal article
    Valtcheva IB, Marchetti P, Livingston AG, 2015,

    Crosslinked polybenzimidazole membranes for organic solvent nanofiltration (OSN): Analysis of crosslinking reaction mechanism and effects of reaction parameters

    , Journal of Membrane Science, Vol: 493, Pages: 568-579, ISSN: 0376-7388

    Recently, polybenzimidazole (PBI) membranes crosslinked with dibromoxylene (DBX) were shown to retain their molecular separation performance in the harsh conditions characteristic of organic solvent nanofiltration (OSN). This work is focused on better understanding of the crosslinking reaction between PBI and DBX, and finding the parameters important for achieving higher degrees of crosslinking. A statistical approach based on Design of Experiments was used to identify the most significant parameters and interactions affecting the crosslinking reaction. High gain in weight and high bromine content after the reaction are expected to be indirectly related to membranes with high crosslinking degrees. Hence, these two responses were measured as a function of reaction temperature, reaction time, excess of DBX, concentration of DBX and reaction solvent (acetonitrile and toluene). All parameters were found to have a positive effect on both responses, and the reaction was found to be faster in acetonitrile than in toluene. All obtained results were statistically evaluated using Analysis of Variance, and a physical interpretation of the statistical models was attempted.Keywords Polybenzimidazole (PBI); Crosslinking reaction; Alkylation; Design of Experiments (DoE); Organic solvent nanofiltration (OSN)
  • Journal article
    Da Silva Burgal J, Peeva L, Marchetti P, Livingston Aet al., 2015,

    Controlling molecular weight cut-off of PEEK nanofiltration membranes using a drying method

    , Journal of Membrane Science, Vol: 493, Pages: 524-538, ISSN: 0376-7388

    In this research paper we report two ways of controlling the molecular weight cut-off (MWCO) of PEEK membranes prepared via phase inversion and subsequent drying. The two methods explored were the change of polymer concentration in the dope solution – 8 wt. %, 10 wt. % and 12 wt. %-and the variation of solvent filling the pores prior to drying – e.g. water, methanol, acetone, tetrahydrofuran and n-heptane. The results show that it is possible to vary the MWCO from 295 g.mol−1 to 1400 g.mol−1 by varying these parameters. A statistical analysis based on a genetic algorithm showed that the Hansen solubility parameter, polarity and their interactions with molar volume were likely to be the most important parameters influencing the performance of PEEK membranes when drying from different solvents. In addition, the drying temperature also proved to have an effect on the membrane performance-the higher the temperature the higher the rejection and the lower the permeance.
  • Journal article
    Karan S, Jiang Z, Livingston AG, 2015,

    Sub-10 nm polyamide nanofilms with ultrafast solvent transport for molecular separation

    , Science, Vol: 348, Pages: 1347-1351, ISSN: 0036-8075

    Membranes with unprecedented solvent permeance and high retention of dissolved solutes are needed to reduce the energy consumed by separations in organic liquids. We used controlled interfacial polymerization to form free-standing polyamide nanofilms less than 10 nanometers in thickness, and incorporated them as separating layers in composite membranes. Manipulation of nanofilm morphology by control of interfacial reaction conditions enabled the creation of smooth or crumpled textures; the nanofilms were sufficiently rigid that the crumpled textures could withstand pressurized filtration, resulting in increased permeable area. Composite membranes comprising crumpled nanofilms on alumina supports provided high retention of solutes, with acetonitrile permeances up to 112 liters per square meter per hour per bar. This is more than two orders of magnitude higher than permeances of commercially available membranes with equivalent solute retention.
  • Journal article
    Gaffney PRJ, Kim JF, Valtcheva IB, Williams GD, Anson MS, Buswell AM, Livingston AGet al., 2015,

    Liquid-phase synthesis of 2′-methyl-RNA on a homostar support through organic-solvent nanofiltration

    , Chemistry-A European Journal, Vol: 21, Pages: 9535-9543, ISSN: 1521-3765

    Due to the discovery of RNAi, oligonucleotides (oligos) have re-emerged as a major pharmaceutical target that may soon be required in ton quantities. However, it is questionable whether solid-phase oligo synthesis (SPOS) methods can provide a scalable synthesis. Liquid-phase oligo synthesis (LPOS) is intrinsically scalable and amenable to standard industrial batch synthesis techniques. However, most reported LPOS strategies rely upon at least one precipitation per chain extension cycle to separate the growing oligonucleotide from reaction debris. Precipitation can be difficult to develop and control on an industrial scale and, because many precipitations would be required to prepare a therapeutic oligonucleotide, we contend that this approach is not viable for large-scale industrial preparation. We are developing an LPOS synthetic strategy for 2′-methyl RNA phosphorothioate that is more amenable to standard batch production techniques, using organic solvent nanofiltration (OSN) as the critical scalable separation technology. We report the first LPOS-OSN preparation of a 2′-Me RNA phosphorothioate 9-mer, using commercial phosphoramidite monomers, and monitoring all reactions by HPLC, 31P NMR spectroscopy and MS.
  • Journal article
    Burgal JDS, Peeva LG, Kumbharkar S, Livingston Aet al., 2015,

    Organic solvent resistant poly(ether-ether-ketone) nanofiltration membranes

    , JOURNAL OF MEMBRANE SCIENCE, Vol: 479, Pages: 105-116, ISSN: 0376-7388
  • Journal article
    Marchetti P, Livingston AG, 2015,

    Predictive membrane transport models for Organic Solvent Nanofiltration: How complex do we need to be?

    , JOURNAL OF MEMBRANE SCIENCE, Vol: 476, Pages: 530-553, ISSN: 0376-7388
  • Conference paper
    Marchetti P, Mechelhoff M, Livingston AG, 2015,

    Tunable-porosity membranes for water treatment by discrete nanoparticle assembly

    , Pages: 196-197
  • Journal article
    Bismarck A, Li K, Livingston A, 2015,

    Editorial "Polymers for membrane applications"

    , REACTIVE & FUNCTIONAL POLYMERS, Vol: 86, Pages: 87-87, ISSN: 1381-5148
  • Journal article
    Szekely G, Valtcheva IB, Kim JF, Livingston AGet al., 2015,

    Molecularly imprinted organic solvent nanofiltration membranes - Revealing molecular recognition and solute rejection behaviour

    , REACTIVE & FUNCTIONAL POLYMERS, Vol: 86, Pages: 215-224, ISSN: 1381-5148
  • Journal article
    Campbell J, Davies RP, Braddock DC, Livingston AGet al., 2015,

    Improving the permeance of hybrid polymer/metal-organic framework (MOF) membranes for organic solvent nanofiltration (OSN) - development of MOF thin films via interfacial synthesis

    , JOURNAL OF MATERIALS CHEMISTRY A, Vol: 3, Pages: 9668-9674, ISSN: 2050-7488
  • Journal article
    Yau HC, Bayazit MK, Gaffney PRJ, Livingston AG, Steinke JHG, Shaffer MSPet al., 2015,

    Synthesis and characterization of branched fullerene-terminated poly(ethylene glycol)s

    , POLYMER CHEMISTRY, Vol: 6, Pages: 1056-1065, ISSN: 1759-9954
  • Journal article
    Marchetti P, Solomon MFJ, Szekely G, Livingston AGet al., 2014,

    Molecular Separation with Organic Solvent Nanofiltration: A Critical Review

    , CHEMICAL REVIEWS, Vol: 114, Pages: 10735-10806, ISSN: 0009-2665
  • Journal article
    Kim JF, Szekely G, Schaepertoens M, Valtcheva IB, Jimenez-Solomon MF, Livingston AGet al., 2014,

    In Situ Solvent Recovery by Organic Solvent Nanofiltration

    , ACS SUSTAINABLE CHEMISTRY & ENGINEERING, Vol: 2, Pages: 2371-2379, ISSN: 2168-0485
  • Journal article
    Szekely G, Jimenez-Solomon MF, Marchetti P, Kim JF, Livingston AGet al., 2014,

    Sustainability assessment of organic solvent nanofiltration: from fabrication to application

    , GREEN CHEMISTRY, Vol: 16, Pages: 4440-4473, ISSN: 1463-9262
  • Journal article
    Peeva L, Burgal JDS, Valtcheva I, Livingston AGet al., 2014,

    Continuous purification of active pharmaceutical ingredients using multistage organic solvent nanofiltration membrane cascade

    , CHEMICAL ENGINEERING SCIENCE, Vol: 116, Pages: 183-194, ISSN: 0009-2509
  • Journal article
    Siddique H, Bhole Y, Peeva LG, Livingston AGet al., 2014,

    Pore preserving crosslinkers for polyimide OSN membranes

    , JOURNAL OF MEMBRANE SCIENCE, Vol: 465, Pages: 138-150, ISSN: 0376-7388

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