Synthesis of a biomimetic zwitterionic pentapolymer to fabricate high-performance PVDF membranes for efficient separation of oil-in-water nano-emulsions
Nadeem Baig, Zeeshan Arshad, Shaikh A. Ali
Abstract
Abstract Oily wastewater from industries has an adverse impact on the environment, human and aquatic life. Poly(vinylidene fluoride) (PVDF) membrane modified with a zwitterionic/hydrophobic pentapolymer (PP) with controlled pore size has been utilized to separate oil from water from their nano-emulsions. The PP has been synthesized in 91% yield via pentapolymerization of four different diallylamine salts [(CH 2 =CHCH 2 ) 2 NH + (CH 2 ) x A − ], bearing CO 2 − , PO 3 H − , SO 3 − , (CH 2 ) 12 NH 2 pendants, and SO 2 in a respective mol ratio of 25:36:25:14:100. Incorporating PP into PVDF has shown a substantially reduced membrane hydrophobicity; the contact angle decreased from 92.5° to 47.4°. The PP-PVDF membranes have demonstrated an excellent capability to deal with the high concentrations of nano-emulsions with a separation efficiency of greater than 97.5%. The flux recovery ratio (FRR) of PP- 5 incorporated PVDF membrane was about 82%, which was substantially higher than the pristine PVDF.