Bio-inspired synthesis and characterization of mesoporous ZnFe2O4 hollow fibers with enhancement of adsorption capacity for acid dye

Magnetic ZnFe2O4 hollow fibers were synthesized via a facile bio-template method involving pore-fabricating and nanoparticle assembling process. The as-prepared kapok-morphic ZnFe2O4 exhibited hollow fiber structure composed of nanocrystallites with grain sizes of 30–50 nm. The adsorption kinetics equilibrium and thermodynamics of acid fuchsin onto ZnFe2O4 were investigated. It was found that the adsorption was spontaneous and exothermic, and the adsorption process was well described by both the Langmuir isotherm model and the pseudo-second order kinetics model. The maximum adsorption capacity of ZnFe2O4 hollow fibers for acid fuchsin was 150.37 mg/g. Electrostatic absorption was conceived as the main adsorption mechanisms.