Development of robust fluorinated TiO2/PVDF composite hollow fiber membrane for CO2 capture in gas-liquid membrane contactor

• Main Authors: Loh, Chun Heng, Wang, Rong, Lin, Yuqing, Xu, Yilin
• Other Authors: School of Civil and Environmental Engineering
• Format: Article
• Language: English
• Published: 2019
• Subjects: Inorganic/Organic Composite Membrane; Gas-liquid Membrane Contactor; Engineering::Civil engineering
• Online Access: https://hdl.handle.net/10356/85345; http://hdl.handle.net/10220/50436
• Institution: Nanyang Technological University

Gas-liquid membrane contactor (GLMC) is a promising method to attain high efficiency for CO2 capture from flue gas, biogas and natural gas. However, membranes used in GLMC are prone to pore wetting due to insufficient hydrophobicity and low chemical resistance, resulting in significant increase in mass transfer resistance. To mitigate this issue, inorganic-organic fluorinated titania/polyvinylidene fluoride (fTiO2/PVDF) composite hollow fiber (HF) membranes was prepared via facile in-situ vapor induced hydrolyzation method, followed by hydrophobic modification. The proposed composite membranes were expected to couple the superb chemical stability of inorganic and high permeability/low cost of organic materials. The continuous fTiO2 layer deposited on top of PVDF substrate was found to possess a tighter microstructure and better hydrophobicity, which effectively prevented the membrane from wetting and lead to a high CO2 absorption flux (12.7 × 10−3 mol m−2 s−1). In a stability test with 21-day operation of GLMC using 1M monoethanolamine (MEA) as the absorbent, the fTiO2/PVDF membrane remained to be intact with a CO2 absorption flux decline of ∼16%, while the pristine PVDF membrane suffered from a flux decline of ∼80% due to membrane damage. Overall, this work provides an insight into the preparation of high-quality inorganic/organic composite HF membranes for CO2 capture in GLMC application.