Evaluation of the Photodegradation of Atrazine in the Presence of β-cyclodextrin Polymer: Experimental Design and Kinetic Study

The degradation of atrazine (ATZ) was studied in the presence of β-cyclodextrin (β-CD) under ultraviolet light irradiation. The β-CD was characterized by modern analytical techniques and the different operating parameters of photodegradation were investigated. Experimental results revealed irregular shapes in the structure of β-CD, and the functional groups of β-CD were present in the glucose units. The BET surface area of β-CD was 285.02 m2/g with a pore volume of 0.172 cc/g and a pore diameter of 2.138 nm, whereas, the x-ray diffraction analysis revealed the polycrystalline nature of β-CD. The z-average diameter of the particle size distribution was determined as 63.21 nm, thermogravimetric analysis data demonstrated weight loss events while the differential thermal analysis data revealed associated energy changes during phase transitions. The photodegradation of ATZ in the presence of β-CD resulted in 80.80% and 59.40% degradation, respectively, for 6.25 mg/L and 100 mg/L of ATZ after 60 min of irradiation time. The treatment method could be described by the Langmuir-Hinshelwood kinetic model, with kc equals 0.1462 mgL-1min-1 and KLH equals 10.45 × 10-2 Lmg-1. Thus, photodegradation with β-CD as a catalyst could be effectively used for the remediation of pesticide-contaminated wastewater.