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

Abstract

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.