Taguchi Optimization of Catalytic Ozonation Process Using Modified Bone Char Ash for Removal of Methylene Blue from Aqueous Solution

Abstract

Methylene blue (MB) dye is an environmental contaminant that has been mostly used in textile industry. Taguchi orthogonal array design was employed as an optimization method to reduce the number of experiments. In this research, bone char ash modified by MgO-Fe catalyst was applied for degradation of MB in catalytic ozonation process (COP) system and operational parameters including initial MB dosages, initial pH, catalyst dose, and contact time were optimized with Taguchi method. Accordingly, the best condition for the removal of MB obtained at initial MB concentration of 20 mg/L, reaction time of 15 minutes, initial pH value of 10, and catalyst concentration of 0.1 g/L. Additionally, optimization of experimental set-up showed that the MB concentration had a notable effect on MB degradation in COP process (55.6%), and reaction time had a negligible effect (1.98%). At this condition, total organic carbon (TOC) removal was determined to be 31% but in longer time, its removal increased to 65%.