Study on the Adsorption of Methyl Red by Bentonite / Chitosan Composites

Abstract

A composite material is formed by using chitosan and bentonite under the condition of dissolution with acetic acid. The material was characterized by scanning electron microscope thermogravimetric analysis and infrared spectroscopy. The effects of initial concentration of methyl red, adsorption time, pH, and amount of adsorbent on adsorption were investigated. Then, the adsorption process was analyzed from kinetics, and related parameters were calculated. The results showed that the composite material has a wider pH range than using chitosan as an adsorbent to adsorb methyl red; The mass ratio of chitosan to bentonite is 0.08:1, the removal rate of methyl red is the best; The amount of adsorbent used is 0.7mg to reach saturation for a volume of 25mL of methyl red solution with a concentration of 20ug/l; the adsorption of methyl red by the material conforms to the pseudo-second-order kinetic model.