Pyrolytic carbon/Cloisite 30B/ZnFe2O4 as reclaimable magnetic nanocomposite for methylene blue decontamination

Abstract

This study prepared a new magnetic nanocomposite of Cloisite 30B and pyrolytic carbon (PC). Its ability as an efficient adsorbent was studied to remove MB dye. The results of the physical-chemical properties showed that the desired absorbents were synthesized and modified PC using ZnFe₂O₄ and Cloisite 30B, improving their properties. The specific surface area of PC/Cloisite 30B/ZnFe₂O₄ (59.66 m²/g) was higher compared to PC (2.51 m²/g) and PC/ZnFe₂O₄ (37.66 m²/g). The magnetic saturation values of PC/ZnFe₂O₄ and PC/Cloisite 30B/ZnFe₂O₄ were 9.19 and 6.36 emu/g, respectively. The maximum dye removal using PC/Cloisite 30B/ZnFe₂O₄ (99.08 %) was determined at pH=10, adsorbent dose of 1 g/L, time of 50 min, temperature of 25 °C, and MB concentration 10 mg/L, respectively. The adsorption followed the pseudo-secondary-order model processes kinetic behavior. The adsorption process of MB dye using the desired absorbents was exothermic and spontaneous. The maximum removal capacity for PC, Cloisite 30B, and PC/ZnFe₂O₄ samples was determined to be 18.48, 28.49, and 43.47 mg/g, respectively, which shows the benefits of PC sample modification. Also, the PC/ZnFe₂O₄ and PC/Cloisite 30B/ZnFe₂O₄ samples can be reused in more than 5 and 7 steps, respectively, which shows their stability in adsorbing MB dye.