Date of Publication
6-2026
Document Type
Master's Thesis
Degree Name
Master of Science in Chemical Engineering
Subject Categories
Chemical Engineering
College
Gokongwei College of Engineering
Department/Unit
Chemical Engineering
Thesis Advisor
Dr. Arnel B. Beltran
Dr. Rhoda B. Leron
Defense Panel Chair
Dr. Aileen Orbecido
Defense Panel Member
Dr. Angelo Earvin S. Choi
Dr. Marwin R. Gallardo
Abstract (English)
The discharge of textile wastewater with high salt concentrations poses a significant environmental challenge and necessitates the development of efficient separation technologies. Loose nanofiltration (LNF) membranes have emerged as promising candidates for dye desalination due to their ability to selectively retain dyes while allowing salts to pass through. In this study, a zwitterionic polyester LNF membrane was developed via interfacial polymerization between zwitterionic dipyridamole (ZDP) and trimesoyl chloride (TMC) on a polyethersulfone (PES) substrate.
Characterization results confirmed the successful incorporation of zwitterionic sulfobetaine groups into the selective layer. The ZDP-TMC/PES membrane exhibited a thinner selective layer of 28.10 nm compared to 58.70 nm for the DP-TMC/PES membrane, lower surface roughness of 3.0 ± 0.2 nm, enhanced hydrophilicity with a water contact angle of 60.2°, and a more balanced surface charge. Compared with the DP-TMC/PES membrane, the ZDP-TMC/PES membrane demonstrated higher water permeance of 65.02 L m-2h-1bar-1 and improved dye/salt selectivity of 176.27, compared to 43.88 L m-2h-1bar-1 and 144.59, respectively, while maintaining Congo red rejection above 99% and NaCl rejection of 1.98%. The optimal membrane was obtained at 0.30 wt% ZDP concentration, 0.40 wt% TMC concentration, 5 min immersion time, and 10 min reaction time. Furthermore, the membrane exhibited excellent antifouling performance with a flux recovery ratio of 99.86% and maintained stable dye rejection and salt passage during 168 h of continuous filtration.
These results demonstrate that zwitterionic modification of dipyridamole effectively enhances membrane hydrophilicity, permeability, selectivity, and fouling resistance. The developed ZDP-TMC/PES membrane shows strong potential as an efficient and stable loose nanofiltration membrane for dye desalination and textile wastewater treatment applications.
Abstract Format
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Abstract (Filipino)
Ang pagtatapon ng ginamit na tubig mula sa industriya ng tela na may mataas na konsentrasyon ng asin sa mga anyong tubig ay isang malaking suliraning pangkapaligiran, kaya naman kinakailangan ang paglinang ng mga mabisang separation technology. Ang mga loose nanofiltration (LNF) membranes ang nakikitang may malaking potensyal na masolusyunan ang dye desalination dahil sa kakayahan nitong piling salain ang dye habang pinapadaan ang mga asin. Sa pag-aaral na ito, isang zwitterionic polyester LNF membrane ang binuo sa pamamagitan ng interfacial polymerization gamit ang zwitterionic dipyridamole at trimesoyl chloride sa isang polyethersulfone (PES) substrate.
Kinumpirma ng mga resulta ng membrane characterization ang matagumpay na pagbuo ng mga zwitterionic sulfobetaine group sa selective layer nito. Ipinakita ng ZDP-TMC/PES membrane na mas manipis ang selective layer nito na may sukat na 28.10 nm kumpara sa 58.70 nm ng DP-TMC/PES membrane. Mayroon din itong mas mababang surface roughness na 3.0 ± 0.2 nm, mas mataas na hydrophilicity na may water contact angle na 60.2°, at mas balanseng surface charge. Kung ikukumpara sa DP-TMC/PES membrane, nagpakita ang ZDP-TMC/PES membrane ng mas mataas na water permeance na 65.02 L m-2h-1bar-1 at pinagbuting dye/salt selectivity na nasa 176.27 kumpara sa 43.88 L m-2h-1bar-1 at 144.59. Kasabay nito, napanatili nito ang mataas na Congo red rejection nang higit 99% at mababang NaCl rejection na nasa 1.98% lamang. Ang pinakamagandang kondisyon para sa membrane ay nakuha sa 0.30 wt% ZDP concentration, 0.40 wt% TMC concentration, 5 min immersion time, at 10 min reaction time. Bukod dito, nagpakita ang membrane ng natatanging antifouling performance na may flux recovery ratio na 99.86%, at napanatili ang stable dye rejection at salt passage sa loob ng 168 oras na filtration.
Ipinapakita ng mga resultang ito na ang zwitterionic modification ng dipyridamole ay epektibong nagpapabuti sa hydrophilicity, permeability, selectivity, at fouling resistance ng membrane. Malaki ang potensyal ng nabuong ZDP-TMC/PES membrane bilang isang mabisa at matatag na loose nanofiltration membrane para sa mga aplikasyon sa dye desalination at pagproseso ng wastewater ng textile industry.
Abstract Format
html
Language
English
Format
Electronic
Keywords
Membrane separation
Recommended Citation
Arada, G. G. (2026). Novel thin-film composite polyester loose nanofiltration membrane using zwitterionic dipyridamole as aqueous monomer for dye desalination. Retrieved from https://animorepository.dlsu.edu.ph/etdm_chemeng/38
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Embargo Period
6-2029
