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Journal articleSultan Z, Graça I, Li Y, et al., 2019,
Membrane fractionation of liquors from lignin-first biorefining, ChemSusChem, Vol: 12, Pages: 1203-1212, ISSN: 1864-5631
For the purposing of each lignin fraction in the lignin liquors, the development of separation strategies to fractionate the lignin streams by MW ranges constitutes a timely challenge to be tackled. Herein, membrane separation was applied to the refining of lignin streams obtained from a lignin-first biorefining process based on H-transfer reactions catalyzed by Raney Ni, using 2-propanol as a part of the lignin extraction liquor and as an H-donor. A two-stage membrane cascade was considered to separate and concentrate the monophenol-rich fraction from the CUB liquor. Building on the experimental results, an economic evaluation of the potential of membrane separation for the refining of lignin streams was undertaken. The membrane performance represents the bottleneck of the costs associated with the separation process. Accordingly, we present a detailed analysis of future developments in the performance required to debottleneck the utilization of membrane separation for lignin refining.
Journal articleDong R, Liu R, Gaffney P, et al., 2019,
Sequence-defined multifunctional polyethers via liquid-phase synthesis with molecular sieving, Nature Chemistry, Vol: 11, Pages: 136-145, ISSN: 1755-4330
Synthetic chemists have devoted tremendous effort towards the production of precision synthetic polymers with defined sequences and specific functions. However, the creation of a general technology that enables precise control over monomer sequence, with efficient isolation of the target polymers, is highly challenging. Here, we report a robust strategy for the production of sequence-defined synthetic polymers through a combination of liquid-phase synthesis and selective molecular sieving. The polymer is assembled in solution with real-time monitoring to ensure couplings proceed to completion, on a three-armed star-shaped macromolecule to maximize efficiency during the molecular sieving process. This approach is applied to the construction of sequence-defined polyethers, with side-arms at precisely defined locations that can undergo site-selective modification after polymerization. Using this versatile strategy, we have introduced structural and functional diversity into sequence-defined polyethers, unlocking their potential for real-life applications in nanotechnology, healthcare and information storage.
Journal articleDong R, Liu R, Gaffney PRJ, et al., 2019,
Author Correction: Sequence-defined multifunctional polyethers via liquid-phase synthesis with molecular sieving, Nature Chemistry, Vol: 11, Pages: 184-184, ISSN: 1755-4330
Correction to: Nature Chemistry https://doi.org/10.1038/s41557-018-0169-6, published online 3 December 2018.
Conference paperButler E, Reid B, Petit C, et al., 2018,
Extended DLVO interactions of a metal-organic framework: Implications on colloidal dispersion, 256th National Meeting and Exposition of the American-Chemical-Society (ACS) - Nanoscience, Nanotechnology and Beyond, Publisher: AMER CHEMICAL SOC, ISSN: 0065-7727
Conference paperDong R, Chen R, Livingston A, 2018,
Iterative synthesis of sequence-defined, multifunctional, biocompatible PEGs for biomedical applications, 256th National Meeting and Exposition of the American-Chemical-Society (ACS) - Nanoscience, Nanotechnology and Beyond, Publisher: AMER CHEMICAL SOC, ISSN: 0065-7727
Journal articleCook M, Gaffney P, Peeva L, et al., 2018,
Roll-to-roll dip coating of three different PIMs for Organic Solvent Nanofiltration, Journal of Membrane Science, Vol: 558, Pages: 52-63, ISSN: 0376-7388
PIM-1, PIM-7, and PIM-8 composite membranes have been fabricated for Organic Solvent Nanofiltration (OSN) on two different support membranes. Both support membranes, PAN and crosslinked Ultem 1000, displayed pore sizes within the range of 20–25 nm as characterised by gas liquid porometry. PIM layers of < 500 nm thickness were formed from dip coating on a roll-to-roll pilot line. The resultant composite membranes exhibited typical MWCOs in the region of 500–800 g mol−1. The quality of coating obtained on the crosslinked Ultem 1000 support membrane was consistently higher for all three PIMs than that obtained on the PAN membrane. The PIM composite membranes coated on to crosslinked Ultem 1000 were stable in a wider range of solvents than those on the PAN support. OSN testing in a model system with isomeric alkane solutes verified that manipulated changes to the molecular architecture of the polymer backbone resulted in a higher separation factor between straight and branched alkane isomers.
Journal articleChen W, Sharifzadeh M, Shah N, et al., 2018,
Iterative peptide synthesis in membrane cascades: Untangling operational decisions, Computers and Chemical Engineering, Vol: 115, Pages: 275-285, ISSN: 0098-1354
Membrane enhanced peptide synthesis (MEPS) combines liquid-phase synthesis with membrane filtration, avoiding time-consuming separation steps such as precipitation and drying. Although performing MEPS in a multi-stage cascade is advantageous over a single-stage configuration in terms of overall yield, this is offset by the complex combination of operational variables such as the diavolume and recycle ratio in each diafiltration process. This research aims to tackle this problem using dynamic process simulation. The results suggest that the two-stage membrane cascade improves the overall yield of MEPS significantly from 72.2% to 95.3%, although more washing is required to remove impurities as the second-stage membrane retains impurities together with the anchored peptide. This clearly indicates a link between process configuration and operation. While the case study is based on the comparison of single-stage and two-stage MEPS, the results are transferable to other biopolymers such as oligonucleotides, and more complex system configurations (e.g. three-stage MEPS).
Journal articleKim JH, Cook M, Park SH, et al., 2018,
A compact and scalable fabrication method for robust thin film composite membranes, GREEN CHEMISTRY, Vol: 20, Pages: 1887-1898, ISSN: 1463-9262
Journal articleJiang Z, Karan S, Livingston AG, 2018,
Water Transport through Ultrathin Polyamide Nanofilms Used for Reverse Osmosis, ADVANCED MATERIALS, Vol: 30, ISSN: 0935-9648
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- Citations: 270
Conference paperLevato G, Corcos A, Dichtel W, et al., 2018,
Novel thin-film composite nanofiltration membranes with covalent organic framework active layer, 255th National Meeting and Exposition of the American-Chemical-Society (ACS) - Nexus of Food, Energy, and Water, Publisher: AMER CHEMICAL SOC, ISSN: 0065-7727
Journal articleKim JH, Moon SJ, Park SH, et al., 2018,
A robust thin film composite membrane incorporating thermally rearranged polymer support for organic solvent nanofiltration and pressure retarded osmosis, JOURNAL OF MEMBRANE SCIENCE, Vol: 550, Pages: 322-331, ISSN: 0376-7388
Journal articleMitev D, Radeva E, Peshev D, et al., 2018,
PECVD modification of nano & ultrafiltration membranes for organic solvent nanofiltration, JOURNAL OF MEMBRANE SCIENCE, Vol: 548, Pages: 540-547, ISSN: 0376-7388
Journal articleCook M, Peeva L, Livingston A, 2018,
Solvent-Free Coating of Epoxysilicones for the Fabrication of Composite Membranes, Industrial & Engineering Chemistry Research, Vol: 57, Pages: 730-739, ISSN: 0888-5885
Solventless coated epoxysilicone composite membranes have been prepared from a UV curable epoxysilicone polymer for organic solvent nanofiltration. Coatings were conducted solventless on a roll-to-roll pilot line using a forward gravure coating technique, and applied on a polyacrylonitrile or cross-linked poly(ether imide) support. Cross-linking of the poly(ether imide) support membrane with propanediamine enhanced the adhesion properties of the epoxysilicone selective layer. Penetration of the coating solution into the porous support membrane was confirmed using scanning electron microscopy with energy-dispersive X-ray spectroscopy. Membranes fabricated using two different gravure heads have been studied, with submicrometer siloxane layer thicknesses achieved. The separation performance of the membranes is observed to be independent of the thickness. It has been possible to achieve membranes with a molecular weight cut-off < 500 g mol–1 in hydrocarbon solvents. Benefits of the fabrication include the ability to UV cross-link under air, elimination of solvent-based coating, and the feasibility of achieving uniform, submicrometer coatings at large scale manufacturing. These membranes comprise a further step toward greener and safer membrane production.
Book chapterPeeva LG, Marchetti P, Livingston AG, 2018,
Nanofiltration operations in nonaqueous systems, Comprehensive Membrane Science and Engineering: Second Edition, Pages: 36-78, ISBN: 9780444637963
Nanofiltration is a pressure-driven membrane process used to remove solutes with molecular weight in the range of 200-2000 g mol-1, typically from aqueous streams. A relatively recent innovation is the extension of nanofiltration (NF) processes to organic solvents (OSs)-an emerging technology referred to as organic solvent nanofiltration (OSN). Separation of molecules present in OSs by NF has great potential in industries ranging from refining to fine chemical and pharmaceutical synthesis, and OSN is currently an area of intensive investigation. This article summarizes the most recent developments in the field of OSN.
Journal articleVogelsang D, Dreimann JM, Wenzel D, et al., 2017,
Continuously Operated Hydroamination - Toward High Catalytic Performance via Organic Solvent Nanofiltration in a Membrane Reactor, Industrial & Engineering Chemistry Research, Vol: 56, Pages: 13634-13641, ISSN: 0888-5885
Still, the hydroamination of dienes to form allylic amines is a challenging task in a continuous operation. Herein, we present the performance of a membrane reactor by the implementation of a continuously operated hydroamination reaction of β-myrcene with morpholine. Via application of a poly ether–ether–ketone (PEEK) membrane, operation at elevated temperatures was possible in an integrated reaction/separation unit. First, the kinetics of the hydroamination reaction and relevant membrane characteristics were determined under optimized reaction conditions. Afterward, these results were incorporated in a reactor/separator model to predict the process behavior. With this, catalyst replenishment was adjusted resulting in stable continuous operation. In the end an increase of the turnover number from 460 to 5135 compared to a batch process was achieved. The desired geranyl amines were obtained in very good yields higher than 80%, while an excellent conversion of β-myrcene above 93% was reached in a long-time stable process.
Conference paperDong R, Chen R, Livingston A, 2017,
Liquid-phase iterative synthesis with OSN: A flexible and scalable platform for precision synthetic macromolecules, 254th National Meeting and Exposition of the American-Chemical-Society (ACS) on Chemistry's Impact on the Global Economy, Publisher: AMER CHEMICAL SOC, ISSN: 0065-7727
Journal articleFoglia F, Karan S, Nania M, et al., 2017,
Neutron Reflectivity and Performance of Polyamide Nanofilms for Water Desalination, ADVANCED FUNCTIONAL MATERIALS, Vol: 27, ISSN: 1616-301X
The structure and hydration of polyamide (PA) membranes are investigated with a combination of neutron and X-ray reflectivity, and their performance is benchmarked in reverse osmosis water desalination. PA membranes are synthesized by the interfacial polymerization of m-phenylenediamine (MPD) and trimesoyl chloride (TMC), varying systematically reaction time, concentration, and stoichiometry, to yield large-area exceptionally planar films of ≈10 nm thickness. Reflectivity is employed to precisely determine membrane thickness and roughness, as well as the (TMC/MPD) concentration profile, and response to hydration in the vapor phase. PA film thickness is found to increase linearly with reaction time, albeit with a nonzero intercept, and the composition cross-sectional profile is found to be uniform, at the conditions investigated. Vapor hydration with H2O and D2O from 0 to 100% relative humidity results in considerable swelling (up to 20%), but also yields uniform cross-sectional profiles. The resulting film thickness is found to be predominantly set by the MPD concentration, while TMC regulates water uptake. A favorable correlation is found between higher swelling and water uptake with permeance. The data provide quantitative insight into the film formation mechanisms and correlate reaction conditions, cross-sectional nanostructure, and performance of the PA active layer in RO membranes for desalination.
Journal articleChen W, Sharifzadeh M, Shah N, et al., 2017,
Implication of Side Reactions in Iterative Biopolymer Synthesis: The Case of Membrane Enhanced Peptide Synthesis, INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH, Vol: 56, Pages: 6796-6804, ISSN: 0888-5885
Membrane enhanced peptide synthesis (MEPS) improves conventional liquid phase synthesis by purifying intermediate products via filtration. A challenging aspect of MEPS is the propagation of unreacted materials and byproducts throughout the iterative synthesis. In this study, we first develop and validate a model of MEPS. The model is then applied to investigate the implications of side reactions (i.e., formation of error sequences) due to incomplete reaction and insufficient removal of amino acids after coupling. Sensitivity analysis shows that increasing the reaction extent for all couplings from 90 to 100% reduces the yield of truncated sequences from 29 to 0%. The formation of repeating sequences is found to be negligible in all case studies due to the large diavolume of post-deprotection diafiltration. This study provides useful insights into the operation of MEPS with particular emphasis on the control of error sequence formation. These insights are transferable to other sequence-controlled biopolymer syntheses.
Conference paperSong Q, Wang A, Zhang TH, et al., 2017,
Polymer Membranes of Intrinsic Microporosity for Molecular Separations, 13th International Conference on Materials Chemistry (MC13)
Journal articleMarchetti P, Peeva L, Livingston A, 2017,
The Selectivity Challenge in Organic Solvent Nanofiltration: Membrane and Process Solutions, ANNUAL REVIEW OF CHEMICAL AND BIOMOLECULAR ENGINEERING, VOL 8, Vol: 8, Pages: 473-497, ISSN: 1947-5438
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