The Atrazine Removal with the Polyaniline Coated Rice Husk as a Cheap Adsorbent

In this study, a composite of rice husk (RH) modified with polyaniline (PANI) was produced and its potential as an adsorbent in removal of atrazine was investigated. Within the scope of the study, the effects of contact time (0-480 min), initial pH (3.5- 9.5), initial atrazine concentration (2-25 mg/L), and PANI/RH amount (0-1.6 g) on treatment efficiency were examined. The optimum treatment efficiency for atrazine (25 mg/L) was found as 58.3% under 120 min., 5.4 of pH, and 1.0 g/50 ml of adsorbent dosage, and at this condition, adsorption capacities (qt) was calculated as 0.58 mg/g. Furthermore, when the initial atrazine concentration was raised from 2 to 25 mg/L, the removal efficiencies decreased from 81.1 to 60.4 %, but the adsorption capacities (qt) increased from 0.067 to 0.629 mg/g. In addition, the efficiency of the adsorption process was evaluated by applying Langmuir and Freundlich isotherm models. Among the performed isotherm models, Freundlich isotherm provided the best correlation for atrazine and the Freundlich constant related to the sorption capacity was calculated as 2.02 mg/g at an initial pH of 5.4 for the 2.0-25 mg/L atrazine at 25 oC. Raw-PANI/RH and used-PANI/RH composites were characterized with FTIR, XRD, and SEM analysis.