Simultaneous Removal of Dye and Chemical Oxygen Demand from Aqueous Solution by Combination Treatment with Ozone and Carbonaceous Material Produced from Waste Biomass

This paper shows the efficacy of the combination of ozonation and adsorbent treatment in removing cationic and anionic dyes (methylene blue and acid orange 7, respectively) and chemical oxygen demand (COD) from wastewater. The adsorbent was prepared with coffee ground, rice bran, and soybean bran as sources of waste biomass, and was calcined at 1000°C. We demonstrated three methods, namely, singular ozonation, singular adsorbent treatment, and the combination of the two treatments. The removal percentage of dye and COD by ozonation was greater than that by adsorbent treatment. However, the incomplete removal of dye and COD through ozonation suggested that singular treatment is not sufficient for this purpose. Subsequently, we evaluated the combination treatment; the removal percentage of dye and COD by this treatment was higher than those from the singular treatments, which indicates that the adsorption and degradation capacities were enhanced. In addition, the calcined adsorbent could be used at least four times. These results show the novelty and utility of this treatment for the removal of dye and COD from wastewater containing dye. [DOI: 10.1380/ejssnt.2018.229]