Role of functional nanoparticles to enhance the polymeric membrane performance for mixture gas separation

To improve the water vapor/gas separation the hydroxylated TiO₂ (OH-TiO₂) nanopartilces have been synthesized and surface of polysulfone (PSf) hollow fiber membrane (HFM) has been coated as thin film nanocomposite (TFN) membranes. To remove the water vapor from mixture gas, hollow fiber membrane has been fabricated and while coating, the OH-TiO₂ nanoparticles have been incorporated in the m-phenylenediamine (MPD) solution to make TFN membrane. Aqueous MPD—OH-TiO₂ nanoparticles mix solutions and organic trimesoyl chloride (TMC) were used to prepare the TFN membranes on the surface of the PSf HFM substrate. Pristine TiO₂ surface was modified to initiate functional groups on the TiO₂ surface to increase the hydrophilicity of the nanoparticles. Fourier transform infrared (FT-IR) spectroscopy was used to confirm the hydroxylation of TiO₂ nanoparticles. The membranes were well characterized using different physicochemical characterization techniques. The membrane performances were evaluated based on water vapor permeance, selectivity, water vapor flux and water vapor removal efficiency. Obtained experimental results designated that the incorporated OH-TiO₂ nanoparticles were dispersed well while interfacial polymerization in the TFN layer and their addition enhanced membrane performances. With an increasing concentration of OH-TiO₂ nanoparticles from 0.025 to 0.2 wt.% compare with MPD solution during the fabrication, water vapor permeance and selectivity significantly enhanced due to the amplified water vapor permeation corridors afforded by the modified OH-TiO₂ nanoparticles. After increasing the concentration of OH-TiO₂ more than 0.2 wt.% in the monomer solution the agglomeration was started. The results revealed that the addition of modified hydroxylated TiO₂ in MPD solution up to 0.2 w/w% (membrane sample TFN-4 (MT(0.5, 0.2)-OH-TiO₂-0.2)) increased the permeate flux and showed the best permeance 1396 GPU and selectivity 510 among the all prepared membranes.