Abstract

In this study, response surface methodology (RSM) was employed for investigating the removal of As(V) from aqueous solution using multiwalled carbon nanotube (MWCNT)/alumina nanocomposite. The synthesized nanocomposite was characterized by scanning electron microscopy and X-ray diffraction. For conducting the experiments, four independent variables of initial As(V) concentration ranging from 0.1 to 0.9 mg L–1, pH 3–11, contact time ranging from 15 to 1,450 min and adsorbent dose 0.5–1.5 g L–1 were selected and consecutively coded as X1, X2, X3, and X4 at three levels (−1, 0, and 1). A second-order polynomial regression model was then applied to predict responses. Regression analysis showed good fit of the experimental data to the second-order polynomial model with R2 value of 0.9409 indicates the high correlation between observed and predicted values. At the optimum conditions that were initial As(V) concentration 0.5 mg L–1, pH 7, contact time 80 min, and adsorbent dose 1 g L–1, the As(V) removal efficiency was about 99.4. This study proved that Box–Behnken design under RSM could efficiently be applied for modeling of As(V) removal by MWCNT/alumina nanocomposite.