Methylene blue dye removal using a nanocomposite prepared from CoFe₂O₄^-enriched activated carbon aided with...

The objective of this study was to assess the effectiveness of a nanocomposite CeAC (cobalt ferrite enriched activated carbon), prepared by enriching activated carbon with cobalt ferrite (CoFe₂O₄) for the elimination of methylene blue (MB), from laboratory modeled wastewater. The CeAC was synthesized by a simple wet homogenization and was then characterized using various methods including ESEM, FTIR, BET, and HR-TEM. The study evaluated the effects of several batch adsorption conditions including pH levels (ranging from 2 to 9), dye concentration (30 to 120 mg/L), CeAC quantity (10 to 100 mg), and temperature (30 °C to 50 °C). The results indicated that adsorption uptake depended on pH level (maximum at pH 7.5), and that as adsorbent dose increased, the uptake decreased. The Langmuir isotherm provided the best fit among the isotherms studied, with the highest monolayer capacity (Q_m) of 267.23 mg g^-1 at 50 °C. Kinetic studies suggested pseudo-second-order kinetics; with the intra-particle diffusion suggesting that the film diffusion controlled the rate limiting steps. According to thermodynamic parameters, sorption is a spontaneous physical adsorption mechanism. The study confirms the potential of CeAC as a reliable and efficient adsorbent to eliminate the cationic dye MB from wastewater.