Magnetic flower-like α-Fe2O3@N–C particles as an efficient adsorbent for removal of 2,4-dichlorophenol: Thermodynamics, kinetics and adsorption mechanism

Magnetic flower-like α-Fe2O3@N-C particles were synthesized by hydrothermal self-assembly method and oxygen-limited carbonisation in a glycerol and ethanol solution system using glucose as the carbon source,iron nitrate as the magnetic source and particle skeleton and urea as the nitrogen source.Four hydrothermal temperatures of 120℃,140℃,160℃ and 180℃ were used to modulate the adsorbent structure.Hydrothermal temperature of 140℃,solution pH=7,and a dosage of 0.06 g are the optimum conditions.The adsorption capacity of 2,4-dichlorophenol(2,4-DCP) onto MC-2 was determined as 108.556 mg g-1at 25℃.Experiments show that the adsorbents all fitted well to the Langmuir isothermal adsorption model and the quasi-secondary kinetic model,and the adsorption behaviour was dominated by monolayer chemisorption.The adsorption process was heat absorbing and spontaneous.Raman and XRD analysis showed that the adsorbent had a stableα-Fe2O3skeleton and carbon layers.FTIR and XPS analysis showed that the adsorbent had hydrogen bonding,electrostatic interaction and π-π bonding to 2,4-dichlorophenol.