Hydrophobic modification of cationic microblocked polyacrylamide and its enhanced flocculation performance for oily wastewater treatment

In this study, a novel amphiphilic flocculant TP-ADL was synthesized using acrylamide, methacryloxyethyltrimethyl ammonium chloride and lauryl acrylate as monomers through UV-light-initiating template copolymerization technology. Copolymerization conditions were optimized towards higher intrinsic viscosity and conversion rate. The Fourier transform infrared spectroscopy and H-1 nuclear magnetic resonance spectroscopy (NMR) analysis confirms the functional groups composition in TP-ADL, and the thermogravimetric (TGA) analysis indicates its good thermal stability. Furthermore, the detailed H-1 NMR and TGA analysis confirms the microblock structure in polymer chain. The amphiphilic rheological characteristics of copolymer were detected according to apparent viscosity. TP-ADL displayed superior flocculation efficiency towards oily wastewater in terms of oil and turbidity removal rate, and zeta potential. The median floc size (d(50)) and fractal dimension (D-f) results indicate a large and compact floc structure. The synergistic effect between cationic microblock structure and inter-molecular hydrophobic association is the main reason for the better treatment efficiency.