Adsorption of hexavalent chromium by graphite-chitosan binary composite

摘要

Graphite chitosan binary (GCB) composite was prepared for hexavalent chromium adsorption from studied water. GCB was characterized by TGA, FTIR, SEM and X-ray diffraction techniques. Wide porous sorptive surface of 3.89 m(2) g(-1) and absorptive functionalities of GCB was due to 20% (w/w) graphite support on chitosan evidenced from FTIR and SEM that impart maximum adsorption at pH 4, agitation with 200 rpm for 180 min. Adsorption studies revealed intraparticle diffusion models and best-fitted kinetics was pseudo 2nd order one. A well-fitted Langmuir isotherm model suggested monolayer adsorption with an adsorption capacity (q (m) ) of 105.6 mg g(-1) and R (2) = 0.945. Sorption mechanisms based on metal ionic interactions, intrusion/diffusion and chemisorptions onto composite. This graphite chitosan binary composite improve sorbent capacity for Cr(VI).