Removal of noxious Eriochrome black T dye from aqueous solution using magnetically metal oxide modified activated carbon derived from Carica papaya seed

Abstract

ABSTRACT In the present study, we have synthesised magnetically metal oxide-modified activated carbon derived from Carica papaya seed (Fe3O4/AC). The Fe3O4/AC materials were characterised using XRD, FE-SEM, EDS, EDX, FT-IR and VSM. The Fe3O4/AC materials serve as a promising sorbent for eliminating anionic azo dye, i.e. EBT from aquatic media. Batch adsorption experiments reveal the optimal contact time of 60 min, initial dye concentration of 20 mg/L, adsorbent dosage of 100 mg, stirring speed of 300 rpm and pH3. The adsorption process was well fitted with the Langmuir isotherm model and pseudo-second-order kinetic due to the high R 2 value. The maximum adsorption capacity (q max) for EBT dye was found to be 50 mg/g. Electrostatic interaction, hydrogen bonding and π–π interaction play an important role in between the adsorbent and adsorbate. The stability of Fe3O4/AC materials was investigated by NaOH to desorb EBT dye molecules located on the surface of Fe3O4/AC. This Fe3O4/AC material is an efficient and economical method for the removal of dye from wastewater.