Optimization of aniline removal using graphite assisted by response surface methodology and box-behnken design

Abstract

Abstract The effectiveness of graphite as adsorbent in the removal of aniline by adsorption was investigated in batch mode based on four manipulated variables: pH of aniline solution (3, 7, 11), temperature of the incubator shaker (30°C, 40°C, 50°C), initial aniline concentration (5 ppm, 15 ppm, 25 ppm) and graphite dosage (0.5 g, 1.5 g, 2.5 g). The four manipulated variables were studied systematically through responses surface methodology (RSM) with 4-level of Box-Behnken design. A total number of 27 sets of designs with 3 centre points were created. The peak wavelengths of aniline working samples were measured at 230 nm and 280 nm using spectrophotometric method. Optimal condition of aniline adsorption revealed 15 ppm of aniline concentration with pH 3 at temperature 40°C using 1.5 g of graphite. The surface morphologies and atomic percentage of fresh and used graphite were examined by FESEM-EDX. Ultimately, graphite is proven to be an alternative in aniline removal, and more importantly, it is accessible easily as they require less processing and are abundant in nature.