Removal of Methylene Blue Dye from Aqueous Solution using PDADMAC Modified ZSM-5 Zeolite as a Novel Adsorbent

In the present work, we modified ZSM-5 zeolite using a bio polymer poly (diallyl dimethyl ammonium chloride) and employed it for the removal of cationic dye, methylene blue from aqueous solution. The chemical and physical properties of the modified ZSM-5 zeolite were investigated using XRD, FTIR, SEM, TEM, nitrogen adsorption, TGA and 27Al NMR. Modified ZSM-5 zeolite possesses high surface area and pore diameter which was confirmed from SEM, TEM and nitrogen adsorption analysis. Adsorption of methylene blue on zeolite was investigated by batch adsorption technique. The effect of different parameters such as zeolite dosage, initial methylene blue concentration, temperature, pH and contact time on the adsorption process was discussed. Maximum adsorption capacity (4.31 mg/g) was achieved using 0.1 g of modified ZSM-5 zeolite at the optimum conditions (initial dye concentration: 10 mg/L, pH 10, temperature: 30 °C and contact time: 300 min). The experimental data were fitted into Langmuir and Freundlich models and the results indicate that the adsorption process followed Freundlich isotherm. Kinetic data were investigated using pseudo-first-order and pseudo-second-order models. Kinetic analysis indicates that pseudo-second-order model is more suitable to describe adsorption of MB on modified ZSM-5 zeolite. The reusability test suggests that the adsorbent could be reused at least six times without significant loss in removal efficiency.