Investigation of atrazine removal in batch and continuous systems with biogenic manganese oxides

Atrazine today is a widely used herbicide. Due to its properties such as long half-life, high chemical stability, surface mobility, and limited water solubility, it is frequently seen at high concentrations in aqueous media. Its presence in aquatic environments creates a serious risk for human and environmental health. Adsorption is a promising technology for the removal of persistent organic materials. In this study; the removal of atrazine by biogenic manganese oxides (BMO) produced by Pseudomonas putida (NRRL B-14878) was investigated in batch and fixed-bed column reactor systems. The maximum atrazine removal was 98.1% at a temperature of 50 °C, pH:12.0 and a atrazine concentration of 0.5 mg/L. Maximum atrazine adsorption capacity was 2.124 mg/g at 50 °C, pH:12.0 and atrazine concentration of 10 mg/L. The Freundlich adsorption model fitted very well to experimental data. Adsorption kinetics followed the pseudo-first-order type kinetic model. The effects of parameters such as feed flow rate, initial atrazine concentration and BMO amount on atrazine removal were investigated in fixed-bed column reactor system. When a flow rate of 4 mL/min, atrazine concentration of 2 mg/L and BMO of 2 g were used, the equilibrium atrazine uptake (qeq) was 0.41 mg/g.