Ultrasonic-assisted synthesis of zeolite/activated carbon@MnO2 composite as a novel adsorbent for treatment of wastewater containing methylene blue and brilliant blue.

Abstract

In this study, zeolite/activated carbon@MnO2 composite was used as a novel adsorbent to eliminate methylene blue (MB) and brilliant blue (BB) dyes from aqueous media. To this end, activated carbon (AC) was produced by Ziziphus Spina-Christi leaves and then used to synthesize zeolite/AC@MnO2 composite. Various analyses such as BET, SEM, EDX, Map, FTIR, and XRD were performed to determine the surface features of the above composite. BET analysis indicated that the aforementioned composite has a mesoporous structure. Also, the best conditions for the adsorption of MB and BB dyes were obtained at pH of 9 and 2, temperature of 25°C, adsorbent dosage of 1 and 2g/L, initial dye concentration of 10mg/L, and contact time of 40 and 60min, respectively. Under optimal conditions, the utmost removal efficiency of MB and BB dyes using the zeolite/AC@MnO2 composite was 98.43% and 96.54%, respectively, indicating significant adsorption efficiencies. Moreover, the utmost adsorption capacity of MB and BB dyes was 67.56 and 66.22mg/g, respectively. Furthermore, intraparticle and film diffusion mechanisms were very important in the adsorption process. Besides, thermodynamic and equilibrium studies indicated that the adsorption process is exothermic, physical, and spontaneous. Generally, the aforementioned composite has a significant adsorption capacity and can be a suitable adsorbent to eliminate cationic dyes from industrial effluents.