Utilization of chitosan/bamboo charcoal composite as reactive dye adsorbent

Abstract

Chitosan/bamboo charcoal composites were prepared by blending chitosan with bamboo charcoal and forming composite beads. The composites were used as reactive dye adsorbents. Adsorption equilibrium experiments were carried out as a function of contact time, bamboo charcoal concentration, pH value, and adsorbent dosage level. The equilibrium time of dye adsorption was found to be 8 h. Composite adsorbent had the highest adsorption efficiency when the weight ratio was 50/50. The maximum dye removal took place at the initial pH value of 4.0. The optimum adsorbent dosage for dye removal was 6.0 g. Under above optimal conditions the maximum dye removal was 98.4%. The adsorption isotherm of chitosan and chitosan/bamboo charcoal composite beads agreed well with the Langmuir model. The maximum adsorption capacity was 3.47 mg/g for chitosan bead and 4.32 mg/g for chitosan/bamboo charcoal composite bead, respectively. SEM micrographs confirm that after adsorption the pores were packed with Reactive Red 152.