Enhanced adsorption of Methylene Blue from aqueous solution by chitosan-g-poly （acrylic acid）/vermiculite hydrogel composites

Enhanced adsorption of Methylene Blue from aqueous solution bychitosan-g-poly (acrylic acid)/vermiculite hydrogel composites

A series of chitosan-g-poly (acrylic acid)/vermiculite hydrogel composites were synthesized and used as adsorbents for theinvestigation of the e ect of process parameters such as vermiculite content, pH of dye solution, contact time, initial concentrationof dye solution, temperature, ionic strength and concentration of surfactant sodium dodecyl sulfate on the removal of Methylene Blue(MB) from aqueous solution. The results showed that the adsorption capacity for dye increased with increasing pH, contact timeand initial dye concentration, but decreased with increasing temperature, ionic strength and sodium dodecyl sulfate concentration inthe present of the surfactant. The adsorption kinetics of MB onto the hydrogel composite followed pseudo second-order kinetics andthe adsorption equilibrium data obeyed Langmuir isotherm. By introducing 10 wt.% vermiculite into chitosan-g-poly (acrylic acid)polymeric network, the obtaining hydrogel composite showed the highest adsorption capacity for MB, and then could be regarded as apotential adsorbent for cationic dye removal in a wastewater treatment process.