Application of Sonocatalyst and Sonophotocatalyst for Degradation of Acid Red 14 in Aqueous Environment

Background & Aims of the Study: Azo dyes are employed in industrial processes such as textile industry to create large quantities of colored sewages that have organic and non-organic materials. So, remediation of them is essential. In this project, degradation and mineralization of Acid red 14 (AR14) that is a mono Azo dye and widely used in the textile industries was investigated by Sonocatalysis and Sono photo catalyst in the presence of homogeneous (Fe3+) photo catalyst. Materials & Methods: This study is an experimental investigation on a laboratory scale. The study performed on synthetic wastewater that hold Acid red 14.The influence of operational parameters such as initial dye concentration and ultrasonic power on the sonochemical degradation was also studied. The optimization of variables was done by one factor at a time method. Results: The efficiency of the Sonophotocatalytic process with Fe3+ was higher than Sonocatalysis and photo catalyst processes alone. The combination of sonolysis, Fe3+ and  photo catalyst caused a highly synergistic effect and the synergy index obtained for Fe3+ Sono photo catalysis was 2.05. Chemical oxygen demand (COD) analysis was used to study the degree of mineralization. After 180 min of reaction, the removal of COD was 15, 25.4 and 55.5% for UV/Fe3+, US/Fe3+ and UV/US/Fe3+ process, respectively. The degradation by photocatalysis and sonolysis followed pseudo first-order with respect to the concentration of AR14. Conclusions: The results showed that the Sono photo catalytic degradation and mineralization of AR14 in the presence of Fe3+ was synergistic, most likely because of the participation of Sono-Fenton and photo-Fenton reactions.