Fixed-bed adsorption of atrazine onto microwave irradiated Aegle marmelos Correa fruit shell: Statistical optimization, process design and breakthrough modeling

摘要

In this study, the feasibility of using microwave irradiated Aegle marmelos Correa fruit shell was investigated in a fixed-bed column towards sorptive removal of Atrazine from aqueous solutions. Characterizations of adsorbent such as SEM, point of zero charge (6.5), surface functional groups, BET surface area (910.31m(2) g(-1)), thermal and elemental analysis were carried out. Box-Behnken response surface methodology was utilized to optimize the process parameters such as influent flow rate (2.5-4.5 ml min(-1)), initial atrazine concentration (2060 mg l(-1)), adsorbent particle size (0.082-0.20 mm), and fixed-bed height (5-10 cm). The highest equilibrium adsorption capacity of atrazine at optimum conditions viz. bed height 9.46 cm, initial atrazine concentration 43.29 mg l(-1), flow rate 4.41 ml min(-1) and adsorbent particle size 0.2 mm were estimated to be 12,303.3 mg g(-1). Single stage batch adsorber was designed using BBD quadratic model for desired purification. Fixed-bed adsorption data obtained at optimum conditions and at different bed heights were fitted into different kinetic models to predict the applicable break-through curve model. Dose-response model best suited model for mathematical description of atrazine removal in fixed bed column over other selected models. (C) 2017 Elsevier B.V. All rights reserved.