화학공학소재연구정보센터
Desalination, Vol.269, No.1-3, 170-176, 2011
Continuous fixed bed adsorption of C.I. Acid Blue 92 by exfoliated graphite: An experimental and modeling study
Removal of C.I. Acid Blue 92(AB92) dye by exfoliated graphite (EG) was investigated. Batch adsorption test results proved that EG can remove the dye with a minimum removal efficiency of 70%. Equilibrium isotherm was analyzed by Freundlich, Langmuir, and Radke-Prausnitz models and the related parameters were estimated. It was found that both Langmuir and Radke-Prausnitz models fit the experimental data satisfactorily. A comprehensive series of column tests were performed to determine the breakthrough curves, and the effects of the feed flow rate, initial dye concentration, and adsorbent dosage on adsorption process were studied. The results showed that the breakthrough time increased in proportion to the increase in the dose of adsorbent, but decreased with increase in flow rate and initial dye concentration. The total uptake of AB92 was found 5.02 (g(dye)/g(EG)) at 27 +/- 2 degrees C for the initial concentration of 30 mg L-1 at 9.6 mL min(-1) feed flow rate. An axial dispersion mathematical model implementing nonlinear isotherm and linear driving force mass transfer assumption were developed for predicting the dynamic behavior of the adsorption column. The results obtained from the mathematical model were in good agreement with the experimental data, which proved the success of the model in predicting the process. (C) 2010 Published by Elsevier B.V.