{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/99464"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/99464","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Development and physicochemical characterization of thin-film composite nanofiltration membranes with covalent organic framework active layers","abstract":"The global demand for water is increasing due to unprecedented population growth, accelerated urbanization, economic development, and climate change. With water demand outpacing supply, intensifying periodic water shortages are driving the development of creative solutions to address this global challenge. These include sustainable and efficient management of traditional water resources, conservation strategies, and the incorporation of alternative water sources including seawater and wastewater effluents. Although more sustainable, these alternative water sources are complex and result in new challenges for providing a safe and reliable supply of drinking water. In comparison to conventional water treatment methods, pressure-driven membrane technologies are advantageous because they offer an effective single-step process for removing pathogens along with organic and inorganic contaminants. Despite their advantages, technical advances, and the development of novel membrane materials in recent decades, the relatively high cost of energy required for membrane processes and operational problems associated with membrane fouling and fouling control strategies have restricted a more widespread implementation of nanofiltration (NF) and reverse osmosis (RO) technologies. In addition, the similar polyamide (PA) chemistry used for most commercially available NF and RO membranes limits the water permeability and solute selectivity that could be achieved. In contrast, covalent organic frameworks (COFs) are an emerging class of materials that offer exceptional opportunities to overcome these challenges. COFs are constructed from modular building blocks to form crystalline, permanently porous materials. Employing two-dimensional (2D) COF active layers in the thin-film composite (TFC) membrane structure should provide selective layers with uniform pores that can be tailored at the molecular level. This molecular-level design allows for control of the pore structure and chemical functionality unlike the empirically optimized PA active layers that currently dominate the membrane technology sector. Furthermore, the ultrathin nature, uniform nanometer-size pores, strength, and durability of 2D COF active layers should provide a desirable combination of high selectivity and water permeability. For the first time, this work demonstrates the capability and potential of using COFs as TFC membrane active layers for water purification applications. Initially, NF active layers of polyimine COF were synthesized via the interfacial polymerization (IP) of terephthalaldehyde and tris(4-aminophenyl)benzene monomers on top of a polyethersulfone (PES) ultrafiltration membrane support. Rutherford backscattering spectrometry and Fourier transform infrared spectroscopy analyses confirmed the presence of an imine-linked film that was reproducibly formed with a thickness of ~10 nm. The rejection efficiencies of the COF NF membrane for a model organic compound, Rhodamine-WT, and a background electrolyte, NaCl, were higher than those of the PES support without the COF film. However, this preliminary work also demonstrated the need for COF NF membranes with smaller active layer pores and alternative support materials. This motivated the investigation of another COF monomer, triformylbenzene, to modulate the pore size and polyacrylonitrile (PAN) as a solvent-resistance support. Although the performance was not optimal in terms of water permeability and solute rejection, the first generation of COF membranes developed in this work represents a new paradigm for membrane development in which the active layer structure is pre-determined and highly controllable.","abstract_html":"The global demand for water is increasing due to unprecedented population growth, accelerated urbanization, economic development, and climate change. With water demand outpacing supply, intensifying periodic water shortages are driving the development of creative solutions to address this global challenge. These include sustainable and efficient management of traditional water resources, conservation strategies, and the incorporation of alternative water sources including seawater and wastewater effluents. Although more sustainable, these alternative water sources are complex and result in new challenges for providing a safe and reliable supply of drinking water. In comparison to conventional water treatment methods, pressure-driven membrane technologies are advantageous because they offer an effective single-step process for removing pathogens along with organic and inorganic contaminants. Despite their advantages, technical advances, and the development of novel membrane materials in recent decades, the relatively high cost of energy required for membrane processes and operational problems associated with membrane fouling and fouling control strategies have restricted a more widespread implementation of nanofiltration (NF) and reverse osmosis (RO) technologies. In addition, the similar polyamide (PA) chemistry used for most commercially available NF and RO membranes limits the water permeability and solute selectivity that could be achieved. In contrast, covalent organic frameworks (COFs) are an emerging class of materials that offer exceptional opportunities to overcome these challenges. COFs are constructed from modular building blocks to form crystalline, permanently porous materials. Employing two-dimensional (2D) COF active layers in the thin-film composite (TFC) membrane structure should provide selective layers with uniform pores that can be tailored at the molecular level. This molecular-level design allows for control of the pore structure and chemical functionality unlike the empirically optimized PA active layers that currently dominate the membrane technology sector. Furthermore, the ultrathin nature, uniform nanometer-size pores, strength, and durability of 2D COF active layers should provide a desirable combination of high selectivity and water permeability. For the first time, this work demonstrates the capability and potential of using COFs as TFC membrane active layers for water purification applications. Initially, NF active layers of polyimine COF were synthesized via the interfacial polymerization (IP) of terephthalaldehyde and tris(4-aminophenyl)benzene monomers on top of a polyethersulfone (PES) ultrafiltration membrane support. Rutherford backscattering spectrometry and Fourier transform infrared spectroscopy analyses confirmed the presence of an imine-linked film that was reproducibly formed with a thickness of ~10 nm. The rejection efficiencies of the COF NF membrane for a model organic compound, Rhodamine-WT, and a background electrolyte, NaCl, were higher than those of the PES support without the COF film. However, this preliminary work also demonstrated the need for COF NF membranes with smaller active layer pores and alternative support materials. This motivated the investigation of another COF monomer, triformylbenzene, to modulate the pore size and polyacrylonitrile (PAN) as a solvent-resistance support. Although the performance was not optimal in terms of water permeability and solute rejection, the first generation of COF membranes developed in this work represents a new paradigm for membrane development in which the active layer structure is pre-determined and highly controllable.","abstract_has_math":false,"creators":["Valentino, Lauren"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Environ Engr in Civil Engr","degree_department":null,"school":null,"contributors":["Mariñas, Benito J.","Dichtel, William R","Espinosa Marzal, Rosa M.","Cusick, Roland"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2018,"date_issued":"2018-03-13T17:29:04Z","date_published":"2018-03-13T17:29:04Z","updated_at":"2026-07-22T22:24:37Z","subjects":["Membrane","Nanofiltration","Covalent organic framework (COF)","Polyimine"],"languages":["en"],"rights":["Copyright 2017 Lauren Valentino"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/2142/99464","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Mariñas, Benito J.","Dichtel, William R","Espinosa Marzal, Rosa M.","Cusick, Roland"]},{"key":"dc:creator","label":"Author","values":["Valentino, Lauren"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2018-03-13T17:29:04Z","2020-03-14T09:15:08Z","2017-09-12","2017-12"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Environ Engr in Civil Engr"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Membrane","Nanofiltration","Covalent organic framework (COF)","Polyimine"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 2017 Lauren Valentino"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2142/99464"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["The global demand for water is increasing due to unprecedented population growth, accelerated urbanization, economic development, and climate change. With water demand outpacing supply, intensifying periodic water shortages are driving the development of creative solutions to address this global challenge. These include sustainable and efficient management of traditional water resources, conservation strategies, and the incorporation of alternative water sources including seawater and wastewater effluents. Although more sustainable, these alternative water sources are complex and result in new challenges for providing a safe and reliable supply of drinking water. In comparison to conventional water treatment methods, pressure-driven membrane technologies are advantageous because they offer an effective single-step process for removing pathogens along with organic and inorganic contaminants. Despite their advantages, technical advances, and the development of novel membrane materials in recent decades, the relatively high cost of energy required for membrane processes and operational problems associated with membrane fouling and fouling control strategies have restricted a more widespread implementation of nanofiltration (NF) and reverse osmosis (RO) technologies. In addition, the similar polyamide (PA) chemistry used for most commercially available NF and RO membranes limits the water permeability and solute selectivity that could be achieved. In contrast, covalent organic frameworks (COFs) are an emerging class of materials that offer exceptional opportunities to overcome these challenges. COFs are constructed from modular building blocks to form crystalline, permanently porous materials. Employing two-dimensional (2D) COF active layers in the thin-film composite (TFC) membrane structure should provide selective layers with uniform pores that can be tailored at the molecular level. This molecular-level design allows for control of the pore structure and chemical functionality unlike the empirically optimized PA active layers that currently dominate the membrane technology sector. Furthermore, the ultrathin nature, uniform nanometer-size pores, strength, and durability of 2D COF active layers should provide a desirable combination of high selectivity and water permeability. For the first time, this work demonstrates the capability and potential of using COFs as TFC membrane active layers for water purification applications. Initially, NF active layers of polyimine COF were synthesized via the interfacial polymerization (IP) of terephthalaldehyde and tris(4-aminophenyl)benzene monomers on top of a polyethersulfone (PES) ultrafiltration membrane support. Rutherford backscattering spectrometry and Fourier transform infrared spectroscopy analyses confirmed the presence of an imine-linked film that was reproducibly formed with a thickness of ~10 nm. The rejection efficiencies of the COF NF membrane for a model organic compound, Rhodamine-WT, and a background electrolyte, NaCl, were higher than those of the PES support without the COF film. However, this preliminary work also demonstrated the need for COF NF membranes with smaller active layer pores and alternative support materials. This motivated the investigation of another COF monomer, triformylbenzene, to modulate the pore size and polyacrylonitrile (PAN) as a solvent-resistance support. Although the performance was not optimal in terms of water permeability and solute rejection, the first generation of COF membranes developed in this work represents a new paradigm for membrane development in which the active layer structure is pre-determined and highly controllable.","Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2019-12-01","The student, Lauren Valentino, accepted the attached license on 2017-09-11 at 13:14.","The student, Lauren Valentino, submitted this Dissertation for approval on 2017-09-11 at 13:15.","This Dissertation was approved for publication on 2017-09-12 at 16:21.","DSpace SAF Submission Ingestion Package generated from Vireo submission #11640 on 2018-03-13 at 10:32:39","Made available in DSpace on 2018-03-13T17:29:04Z (GMT). No. of bitstreams: 2 VALENTINO-DISSERTATION-2017.pdf: 64781256 bytes, checksum: 70c37b477de671df386b7982f8069bb0 (MD5) LICENSE.txt: 4213 bytes, checksum: 44c491771760c33d4f26e0bcce13f876 (MD5) Previous issue date: 2017-09-12","Embargo set by: Seth Robbins for item 105431 Lift date: 2020-03-13T17:29:20Z Reason: Author requested closed access (OA after 2yrs) in Vireo ETD system","Embargo set by: Seth Robbins for item 105431 Lift date: 2020-03-13T17:32:30Z Reason: Author requested closed access (OA after 2yrs) in Vireo ETD system","Embargo set by: Seth Robbins for item 105431 Lift date: 2020-03-13T17:36:05Z Reason: Author requested closed access (OA after 2yrs) in Vireo ETD system","Limited Restriction Lifted for Item 105431 on 2020-03-14T09:15:08Z."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Development and physicochemical characterization of thin-film composite nanofiltration membranes with covalent organic framework active layers"]}]}],"canonical_facts":{"dc:contributor":["Mariñas, Benito J.","Dichtel, William R","Espinosa Marzal, Rosa M.","Cusick, Roland"],"dc:creator":["Valentino, Lauren"],"dc:date":["2018-03-13T17:29:04Z","2020-03-14T09:15:08Z","2017-09-12","2017-12"],"dc:description":["The global demand for water is increasing due to unprecedented population growth, accelerated urbanization, economic development, and climate change. With water demand outpacing supply, intensifying periodic water shortages are driving the development of creative solutions to address this global challenge. These include sustainable and efficient management of traditional water resources, conservation strategies, and the incorporation of alternative water sources including seawater and wastewater effluents. Although more sustainable, these alternative water sources are complex and result in new challenges for providing a safe and reliable supply of drinking water. In comparison to conventional water treatment methods, pressure-driven membrane technologies are advantageous because they offer an effective single-step process for removing pathogens along with organic and inorganic contaminants. Despite their advantages, technical advances, and the development of novel membrane materials in recent decades, the relatively high cost of energy required for membrane processes and operational problems associated with membrane fouling and fouling control strategies have restricted a more widespread implementation of nanofiltration (NF) and reverse osmosis (RO) technologies. In addition, the similar polyamide (PA) chemistry used for most commercially available NF and RO membranes limits the water permeability and solute selectivity that could be achieved. In contrast, covalent organic frameworks (COFs) are an emerging class of materials that offer exceptional opportunities to overcome these challenges. COFs are constructed from modular building blocks to form crystalline, permanently porous materials. Employing two-dimensional (2D) COF active layers in the thin-film composite (TFC) membrane structure should provide selective layers with uniform pores that can be tailored at the molecular level. This molecular-level design allows for control of the pore structure and chemical functionality unlike the empirically optimized PA active layers that currently dominate the membrane technology sector. Furthermore, the ultrathin nature, uniform nanometer-size pores, strength, and durability of 2D COF active layers should provide a desirable combination of high selectivity and water permeability. For the first time, this work demonstrates the capability and potential of using COFs as TFC membrane active layers for water purification applications. Initially, NF active layers of polyimine COF were synthesized via the interfacial polymerization (IP) of terephthalaldehyde and tris(4-aminophenyl)benzene monomers on top of a polyethersulfone (PES) ultrafiltration membrane support. Rutherford backscattering spectrometry and Fourier transform infrared spectroscopy analyses confirmed the presence of an imine-linked film that was reproducibly formed with a thickness of ~10 nm. The rejection efficiencies of the COF NF membrane for a model organic compound, Rhodamine-WT, and a background electrolyte, NaCl, were higher than those of the PES support without the COF film. However, this preliminary work also demonstrated the need for COF NF membranes with smaller active layer pores and alternative support materials. This motivated the investigation of another COF monomer, triformylbenzene, to modulate the pore size and polyacrylonitrile (PAN) as a solvent-resistance support. Although the performance was not optimal in terms of water permeability and solute rejection, the first generation of COF membranes developed in this work represents a new paradigm for membrane development in which the active layer structure is pre-determined and highly controllable.","Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2019-12-01","The student, Lauren Valentino, accepted the attached license on 2017-09-11 at 13:14.","The student, Lauren Valentino, submitted this Dissertation for approval on 2017-09-11 at 13:15.","This Dissertation was approved for publication on 2017-09-12 at 16:21.","DSpace SAF Submission Ingestion Package generated from Vireo submission #11640 on 2018-03-13 at 10:32:39","Made available in DSpace on 2018-03-13T17:29:04Z (GMT). No. of bitstreams: 2 VALENTINO-DISSERTATION-2017.pdf: 64781256 bytes, checksum: 70c37b477de671df386b7982f8069bb0 (MD5) LICENSE.txt: 4213 bytes, checksum: 44c491771760c33d4f26e0bcce13f876 (MD5) Previous issue date: 2017-09-12","Embargo set by: Seth Robbins for item 105431 Lift date: 2020-03-13T17:29:20Z Reason: Author requested closed access (OA after 2yrs) in Vireo ETD system","Embargo set by: Seth Robbins for item 105431 Lift date: 2020-03-13T17:32:30Z Reason: Author requested closed access (OA after 2yrs) in Vireo ETD system","Embargo set by: Seth Robbins for item 105431 Lift date: 2020-03-13T17:36:05Z Reason: Author requested closed access (OA after 2yrs) in Vireo ETD system","Limited Restriction Lifted for Item 105431 on 2020-03-14T09:15:08Z."],"dc:format":["application/pdf"],"dc:identifier":["http://hdl.handle.net/2142/99464"],"dc:language":["en"],"dc:rights":["Copyright 2017 Lauren Valentino"],"dc:subject":["Membrane","Nanofiltration","Covalent organic framework (COF)","Polyimine"],"dc:title":["Development and physicochemical characterization of thin-film composite nanofiltration membranes with covalent organic framework active layers"],"dc:type":["text"],"thesis:degree_discipline":["Environ Engr in Civil Engr"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:24:37Z"}