Modified polyamide membrane with TiO2 nanoparticles, application for forward Osmosis, a molecular dynamics simulation study

Desalination of seawater is a significant challenge for arid regions and is the best way to obtain water resources. Today, many desalination methods are used, such as membrane desalination including reverse osmosis (RO) and forward Osmosis (FO). In forward Osmosis, unlike reverse Osmosis, energy consumption is much less and more economical. The various types of polymeric membranes are commonly used in the Osmosis processes such as polyamide (PA) polymer. Polyamide (PA) membranes are known for their selective permeability to water and are extensively used in the seawater desalination. The use of non-toxic inorganic nanoparticles improves the polyamide membrane and increases its efficiency in the forward Osmosis process. This study investigates the efficiency of a modified polyamide membrane with different mole ratios of TiO2 anatase nanoparticles in seawater desalination by using the molecular dynamics (MD) method during forward Osmosis simulation. The self-diffusion coefficients of water in forward Osmosis for PA membranes modified with 10−4, 10−3, 10−1, and 1 wt% of TiO2 were found to be 1.14, 1.11, 1.33 and 1.29×10−9 m2s−1, respectively. The membrane with 0.1% TiO2 demonstrated a self-diffusion coefficient that aligns exceptionally well with the experimentally observed diffusion coefficient for the PA membrane in forward Osmosis.