Evaluation of the effect of silica nanoparticles, temperature and pressure on the performance of PSF/PEG/SiO2 mixed matrix membranes: A molecular dynamics simulation (MD) and design of experiments (DOE) study

Abstract

The fabrication of mixed matrix membranes (MMMs) is of particular importance due to its advantages over neat or composite membranes. The performance of mixed matrix membranes (permeability and selectivity) is a function of the type and fraction of the nanoparticles in the membrane (filler loading), the operating temperature and pressure. Moreover, the interaction of the permeating gas with the polymers and nanoparticles affects the MMMs’ performance. In this study, molecular dynamics (MD) simulations and design of experiments (DOE) method were used to study the effect of silica nanoparticle loadings, temperature and pressure on the transport properties of CO2, CH4 and N2 gases in a PSF-PEG-silica mixed matrix membrane. In the MD simulations, the temperature and silica content loading varied from 25–45 °C and 0–20 wt%, respectively. In the DOE study, the range for the temperature and silica content loading variation was kept the same as considered in the MD simulations. The experimental pressure in the DOE was 0–10 bar. The experimental and simulation results were in good agreement and showed that the three most significant factors on the membrane performance from highest to lowest were silica particle loading, temperature and pressure, respectively.