Elimination performance of methylene blue, methyl violet, and Nile blue from aqueous media using AC/CoFe2O4 as a recyclable magnetic composite

Environ Sci Pollut Res Int. 2019 Jul;26(19):19523-19539. doi: 10.1007/s11356-019-05282-z. Epub 2019 May 10.

Abstract

The present paper describes the sono-assisted adsorption (sono-adsorption) of methylene blue (MB), methyl violet (MV), and Nile blue (NB) from aqueous solution by AC/CoFe2O4 magnetic composite. FT-IR, TGA-DTG, VSM, XRD, TEM, SEM, EDX, Map, and Raman analysis were used to characterize the magnetic composite. The magnetization saturation value of AC/CoFe2O4 magnetic composite was determined to be 53.06 emu/g. Dye sono-adsorption efficiency was increased by increasing adsorbent dose, pH value, and contact time, but not dye concentration. Pseudo-first-order, pseudo-second-order, and intra-particle diffusion models were used to study the kinetic behavior of the cationic dye sono-adsorption. The sono-adsorption kinetics was reasonably followed by pseudo-second-order model (R2 > 0.998). The results showed that the Freundlich model (R2 > 0.976) was more able to describe the sono-adsorption equilibrium behavior than Langmuir, D-R, and Scatchard models. The maximum sono-adsorption capacity of NB, MV, and MB was determined as 86.24, 83.90, and 87.48 mg/g, respectively. Based on the parameters derived from isotherm modeling (RL, n, and E), the sono-adsorption process of cationic dyes is desirable and physical. An increase in NaCl concentration reduced the sono-adsorption efficiency for all dyes. Also, the adsorption-desorption of AC/CoFe2O4 magnetic was studied up to 10 stages, and it was confirmed that the sono-adsorption efficiency is acceptable up to the eight stage. AC/CoFe2O4 magnetic composite is, therefore, an affordable and recyclable adsorbent to remove the molecule of NB, MV, and MB dyes from aqueous media.

Keywords: Activated carbon/cobalt ferrite; Aqueous media; Cationic dye; Sono-adsorption; Ultrasonic.

MeSH terms

  • Adsorption
  • Charcoal / chemistry*
  • Cobalt / chemistry*
  • Coloring Agents / analysis*
  • Diffusion
  • Ferric Compounds / chemistry*
  • Gentian Violet / analysis
  • Hydrogen-Ion Concentration
  • Kinetics
  • Magnetite Nanoparticles / chemistry*
  • Methylene Blue / analysis
  • Oxazines / analysis
  • Water Pollutants, Chemical / analysis*
  • Water Purification / methods*

Substances

  • Coloring Agents
  • Ferric Compounds
  • Magnetite Nanoparticles
  • Oxazines
  • Water Pollutants, Chemical
  • cobalt ferrite
  • Charcoal
  • Nile Blue
  • Cobalt
  • Gentian Violet
  • Methylene Blue