PMO synthesized and functionalized by p-phenylenediamine as new nanofiller in PES-nanofiltration membrane matrix for efficient treatment of organic dye, heavy metal, and salts from wastewater

Highly ordered periodic mesoporous organosilica (PMO) with large-pores (9.3 nm) synthesized using novel and cost-effective route. The synthesized PMO was then functionalized by p-phenylenediamine (PPD) and incorporated in polyethersulfone (PES) nanofiltration membrane‌ with various dosage using phase inversion method. The prepared membranes were characterized with FT-IR/ATR, FE-SEM and EDX techniques. The overall porosity, the mean of pore radius, water contact angle, fouling, permeation, and rejection were computed. As a result, the hydrophilicity and the pure water flux of membranes were significantly enhanced after modification with PMO-PPD due to its high hydrophilic nature as nanofiller. Ultimately, the modified membrane with 0.25 wt% of PPD was found the ideal membrane with water contact angle of 54.2%, pure water flux of 33.7 L/m² h, porosity of 74.1%, and mean pore radius of 4.96 nm. This membrane showed the maximum increase in water flux and superlative anti-fouling growth when compared to the other studied membranes. Moreover, among modified membranes with various quantity of PPD, the performance of the PES-PMO-PPD 0.25 wt% was the best for rejection of MO dye (96.7%), Pb(II) (93.1%), Na₂SO₄ (73.0%), MgSO₄ (41.6%), and NaCl (33.7%).