Combination of Plackett Burman and response surface methodology experimental design to optimize Malachite Green dye removal from aqueous environment

Abstract

Abstract The present study focuses on the immobilization of titanium dioxide (TiO2) for the remediation of Malachite Green (MG) dye from aqueous solution. The immobilization approach would overcome the problem associated with separation of fine TiO2 particles that are often encountered in photodegradation process. Surface characterization study was performed using field emission scanning electron microscope (FESEM) and atomic force microscope (AFM). Plackett-Burman design was applied to identify the significant factors whereas Response Surface Methodology (RSM) was used to evaluate the interaction between these variables. The MG removal process was pH and concentration dependent. Kinetic studies showed that all experiments fitted well in the first order kinetics model. The percentage removal of MG by the thin films remained almost constant after five repetitive usages. Under the optimum conditions (pH = 8; initial dye concentration: 5 mg/L; catalyst dosage: 0.15 g), the percentage removal of MG was estimated to be 98.11%.