Basic Red 46 removal by potentially low cost biosorbent

Abstract

Removal of Basic Red 46 dye (BR 46) was investigated by using low cost biosorbent such as raw rice husk (RH) and rice husk ash (RHA). Biosorption studies were carried out in batch modes of operation for removal of BR 46 onto RH and RHA. The studies were considering few operating parameters including biosorbent dosage (0.2-1.0 g), initial dye concentration (50-250 mg/L) and initial pH (3-11). The effects of each parameter in BR 46 removal were explored for both RH and RHA within 70 min. It was found that the percentage of BR 46 removal increased with the increasing of biosorbent dosage and initial pH; and decreased with the increasing of initial BR 46 concentration. The characterization of surface morphology for both RH and RHA was observed using Scanning Electron Microscope (SEM). Analysis of SEM showed that morphology surface of RHA high in porosity compared to RH. It was proven by better percentage removal of BR 46. The result showed that RHA is more effective biosorbent compared to RH in removal of BR 46. The optimization study of BR 46 removal was conducted using Central Composite Design (CCD) of response surface methodology (RSM). The predicted optimum condition by RSM for the BR 46 removal was at 0.54 g biosorbent dosage, 44.44 mg/L of initial concentration and at pH 7.01 that removed 97.02 % of BR 46.