One-step synthesis of chitosan-polyethyleneimine with calcium chloride as effective adsorbent for Acid Red 88 removal

Chitosan-polyethyleneimine with calcium chloride as ionic cross-linker (CsPC) was synthesized as a new kind of adsorbent using a simple, green and cost-effective technique. The adsorption properties of the adsorbent for Acid Red 88 (AR88) dye, as a model analyte, were investigated in a batch system as the function of solution pH (pH 3-12), initial AR88 concentration (50-500 mg L-1), contact time (0-24 h), and temperature (30-50 degrees C.). Results showed that the adsorption process obeyed the pseudo-first order kinetic model and the adsorption rate was governed by both intra-particle and liquid-film mechanism. Equilibrium data were well correlated with the Freundlich isotherm model, with the calculated maximum adsorption capacity (q(m)) of 1000 mg g(-1) at 30 T. The findings underlined CsPC to be an effective and efficient adsorbent, which can be easily synthesized via one-step process with promising prospects for the removal of AR88 or any other similar dyes from the aqueous solutions. (C) 2019 Elsevier B.V. All rights reserved.