CO2 separation using surface-functionalized SiO2 nanoparticles incorporated ultra-thin film composite mixed matrix membranes for post-combustion carbon capture

• Published in: Journal of membrane science 2016-10, Vol.515, p.54-62
• Main Authors: Kim, Jinguk, Fu, Qiang, Xie, Ke, Scofield, Joel M.P., Kentish, Sandra E., Qiao, Greg G.
• Format: Article
• Language: English
• Subjects: Mixed matrix membranes; Polydopamine; Polyethyleneimine; Silica nanoparticles; Ultra-thin film composite membranes
• ISSN: 0376-7388; 1873-3123
• DOI: 10.1016/j.memsci.2016.05.029

CO2 separation across polyethylene glycol (PEG)-based ultra-thin film composite mixed matrix membranes (UTFC-MMMs) containing surface-functionalized SiO2 nanoparticles (SFSNPs) were investigated. The SFSNPs were prepared by physicochemical adsorption of polyethyleneimine (PEI), polydopamine (PDA) and codeposition of PEI and PDA onto the porous SiO2 nanoparticles (diameter of ~10nm). A cross-linked PEG-based polymer incorporating the SFSNPs was formed into an ultra-thin, CO2 selective layer of ~ 55nm via a novel nano-coating technology, namely continuous assembly of polymers (CAP). The resulting PEG-based UTFC-MMMs demonstrate the potential of ultra thin films prepared by the CAP nanotechnology to enhance CO2 separation. The mixed matrix membranes achieved a CO2 permeance of ~1300GPU (1GPU=10−6cm3 (STP)cm−2s−1cmHg−1) and a favorable CO2/N2 selectivity of 27, which is a 30% and 25% rise in CO2 permeance and CO2/N2 selectivity respectively above the values obtained from simple PEG-based UTFC membranes. [Display omitted] •Newly developed PEG-based UTFC-MMMs incorporating surface-functionalized SiO2 nanoparticles (SFSNPs) with PDA and/or PEI.•Well tuned interface morphologies of the SiO2 nanoparticles by manipulating the nanoparticle surface charges.•The SFSNPs incorporated within the PEG matrix fabricated via CAP nanotechnology to form a nano scale CO2 selective layer.