Performance Enhancement of Nanocomposite Nano-filtration Membranes Modified by Various Amine Groups: Increase in Flux and Improvement of Separation Properties of Pollutants from Wastewater

In the present study, Fe3O4@SiO2-NH2 and Fe3O4@SiO2-CS biocompatible nanocomposites were synthesized using Fe3O4 MNPs, amorphous silica extracted from rice husk and wheat straw agricultural wastes, and APTMS and CS functional groups and applied as an efficient nanofiller to modify PES NF membranes structure. Structural analyses confirmed the fine structure of synthesized nanocomposites and fabricated membranes. NFM-WS membrane modified by Fe3O4@SiO2-CS nanocomposite with 70.6 L m–2 h–1 had higher pure water flux compared with NFM-RH membrane modified by Fe3O4@SiO2-NH2 nanocomposite with 65.4 L m–2 h–1. Both membranes showed the highest salt rejection with more than 80% for Na2SO4 and the lowest salt rejection with about 10% for MgCl2. Performance of NFM-RH and NFM-WS membranes for removal of Cd2+ heavy metal ions were almost the same as 97 and 98%, respectively. NFM-RH and NFM-WS membranes indicated high performance with more than 98% for removal of MR dye. NFM-RH and NFM-WS membranes by FRR of more than 88 and 93%, respectively, demonstrated an excellent flux recovery ratio. Also, Rt and Rir of NFM-RH membrane were about 69 and 12%, respectively, and Rt and Rir of NFM-WS membrane were about 50 and 7%, respectively, which displayed excellent antifouling properties of fabricated NF membranes. In conclusion, fabricated NF membranes are so efficient for water treatment and in terms of environmental are low cost and due to their primary production source are biocompatible.