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.