TiO2 ceramic membrane decorated with Fe3O4–Ag composite nanoparticles for produced water treatment

This study focused on the surface modification of commercial TiO2 membranes with Fe3O4 decorated silver (Ag) nanoparticles (Fe3O4–Ag) via chemical attachment. Firstly, the Ag concentration on Fe3O4 was optimized, and different composites were prepared and characterized. Secondly, the optimal composite was used to prepare novel TiO2/Fe3O4–Ag ceramic membranes via surface coating through tetraethyl orthosilicate (TEOS) crosslinking. The membranes were characterized using SEM, EDX, FTIR, XRD, and contact angle. Biofouling resistance of the membranes was investigated using the Coomassie Blue dye method. The coated membranes were tested for water flux, chemical oxygen demand (COD) rejection, and biofouling resistance. Results showed that all coated membranes exhibited higher water flux. For example, the membrane with a 1.25 wt% Fe3O4–Ag coating showed the highest filtration flux of 1445 L/m2h (LMH) compared to the pristine membrane (379 LMH) without compromising the COD rejection. The resistance of the membrane to biofouling increased with the increase of Fe3O4–Ag nanoparticle concentration. The obtained results demonstrate the great potential of TiO2/Fe3O4–Ag ceramic membranes for the treatment of produced water.