Error Analysis of Adsorption Isotherm Models for Sulfamethazine onto Multi Walled Carbon Nanotubes

Abstract

In the present study, Multi walled carbon nanotubes (MWCNTs) was used for the adsorption of Sulfamethazine (SMZ) antibiotics. The adsorbent was characterized by scanning electron microscopy, surface area (BET) and transmission electron microscopy. Batch experiments were carried out by varying the parameters like contact time, adsorbent dosage and initial Sulfamethazine concentration at fixed pH and temperature. The equilibrium data were tested with Langmuir, Freundlich, Tempkin, Dubinin–Radushkevich (D–R), Redlich-Peterson (R-P), Sips, Toth and Khan isotherm models at five Error Analysis EABS, X2, ARE, RMSE and SD and it was found that the Langmuir and Toth isotherms best fitted the adsorption of SMZ with highest value of R2 and lowest overall experimental error. Also according to the results, a maximum removal efficiency of 99.1% was obtained at pH of 7 and the contact time of 60 min; initial SMZ concentration 20 mg/L and adsorbent dose 0.8 g/L.