Anaerobic Co-digestion of 2,4-Dichlorophenoxyacetic Acid with Starch Followed by Aerobic Post-treatment and Identification of Dominant Bacteria

Abstract

This study was conducted to investigate the new method comprising of sequential anaerobic followed by aerobic batch reactor treatment for 2,4-dichlorophenoxyacetic acid (2,4-D). The various parameters influencing on the anaerobic digestion like pH, temperature, oxidation reduction potential (ORP) have been monitored during the 60 days study period. pH range of 6.5–7.2, temperature greater than 31.4 °C and ORP values between −250 and −300 mV have reported better reactor performance with high 2,4-D removal and biogas production. The complete biotransformation of 2,4-D in the anaerobic reactor is indicated by disappearance of intensity peak in the high-performance liquid chromatograph (HPLC) report, high biogas production of 12–18% than control and COD removal efficiency of 99%. Dominant bacterial community in the sludge was identified using SEM images. The results of this study indicate that anaerobic reactor and aerobic post-treatment method can make the treatment highly efficient.