Synthesis of a novel polyacrylamide/bentonite micro-composite for coagulation and flocculation water treatment

A novel poly(acrylamide)/bentonite micro-composite (PAM/BC) was synthesized via in-situ radical polymerization of acrylamide in the presence of bleaching clay (BC), serving as an inorganic filler. The resulting micro-composite was comprehensively characterized by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDX) to elucidate its thermal, structural, and morphological properties. The coagulation-flocculation performance of PAM/BC was evaluated in a 30 mg/L clay suspension using both Jar-test and semi-industrial pilot-scale experiments. The micro-composite achieved turbidity removal efficiencies exceeding 70%, with optimal conditions at pH 6.7 and a flocculant dose of 1.41 mg/L. Comparative assessment with conventional flocculants confirmed the superior performance of PAM/BC. These results highlight the potential of PAM/BC as an efficient, low-dose, and environmentally compatible flocculant for water treatment applications.