A Novel Material Poly(n-Acryloyl Grafted Kaolin for Efficient Elimination of Malachite Green Dye From Aqueous Environments

Abstract

In the present work, poly(N-acryloyl-L-serine) grafted-kaolin (PNALS@K) synthesized with the surface-initiated reversible addition fragmentation chain transfer (SI-RAFT) polymerization method is reported for the efficient removal of malachite green (MG) dye from aqueous environments. The characterization of PNALS@K was carried out by scanning electron microscopy (SEM), x-ray photoelectron spectroscopy (XPS), energy dispersive x-ray spectroscopy (EDX), and contact angle measurements. The surface characterization analysis indicates there is a thin layer of PNALS on the kaolin surface. Four parameters (starting pH, starting MG concentration (C-o), adsorbent dosage (m), and contact time (t)) were evaluated using response surface methodology (RSM) combined with central composite design (CCD) for the removal of MG by PNALS@K. The optimum adsorption conditions for the removal of MG using PNALS@K were determined as starting pH = 8.92, C-o = 23.49 mg/L, m = 17.44 mg, and t = 72.2 min. The results indicated that PNALS@K has maximum adsorption decolorization performance of 98.90% for MG% removal at the optimal points. Moreover, adsorption data obeyed the Weber-Morris, liquid film diffusion and pseudo-second-order kinetic models. According to the isotherm results, it was also observed that Freundlich isotherm model presented a better fit.