Anaerobic treatment of N-(phosphonometyl) glycine using mixed culture in batch reactor

Abstract

Pesticides are chemicals and preparations used in agricultural control practice and research. They are used to prevent and control pests. Pesticides are toxic and biocidal substances. The unconscious and uncontrolled use of pesticides in order to provide high yields in agricultural areas is an important problem for human health and the environment. For this reason, biodegredation of pesticides was gained importance in recent years. N- (phosphonomethyl) glycine formulated as isopropylamine salt, is a broad spectrum herbicide with high activity and effective destruction. In this study, the optimization of anaerobic treatment of N- (phosphonomethyl) glycine was investigated by applying a statistical-based experimental design. Full factorial experiments with different initial pesticide concentrations and cosubstrate types were established and 9 different experimental setup were established. The experiments carried out in 2 replicates. The experiments were carried out in Oxitop C flasks in a working volume of 200 mL with stirring. The pH was adjusted to 7 ± 0.2. The experiments carried out at 35oC for 30 days. At the end of the process, the removal of inlet and outlet COD and pesticide values were analyzed. As a result, the most efficient COD removal was obtained with 99 % at a pesticide concentration of 5 mg L-1 and glucose as cosubstrate. The highest pesticide removal was found to be 75 % at a pesticide concentration of 25 mg L-1 and glucose as cosubstrate. 5 mg. L-1pesticide containing inlet concentration had toxic effect over 19% of the Vibrio fischeria before treatment, while no toxic effect was observed after treatment. This shows that the toxic value of wastewater containing pesticides decreased.