Separation and Purification Technology, Vol.179, 184-193, 2017
Magnetically recyclable Fe3O4/Bi2S3 microspheres for effective removal of Congo red dye by simultaneous adsorption and photocatalytic regeneration
Novel magnetic bayberry-like Fe3O4/Bi2S3 microspheres (Fe3O4/Bi2S3 MSs) combining highly effective adsorption and photocatalytic regeneration were prepared by a facile hydrothermal method. The resultant Fe3O4/Bi2S3 MSs were characterized by XRD, SEM, EDS, VSM, BET and DRS. Fe3O4/Bi2S3 MSs possessed a relative large surface area of 36.0 m(2) g(-1) and narrow pore size distribution around 4.72 nm. The equilibrium and kinetics of adsorption process followed the Langmuir isotherm model and pseudo-second-order kinetic model, respectively. Maximum adsorption capacity of CR as 92.24 mg g(-1) was achieved on Fe3O4/Bi2S3 MSs, while only 66.28 mg g(-1) was found on Bi2S3 MSs. High saturation magnetization, low coercivity and remnant magnetization values of Fe3O4/Bi2S3 MSs indicated that easy separation and fast re-dispersion in aqueous solution can be realized. Whats more important, Fe3O4/Bi2S3 MSs with a stronger absorption in the visible light region can be regenerated by photocatalysis under simulated solar light irradiation. Fe3O4/Bi2S3 MSs also showed excellent stability and reusability for continuous removal of Congo red dye by synergistic adsorption and photocatalytic regeneration. As a result, Fe3O4/Bi2S3 MSs provided effective and conveniently recyclable materials for environmental remediation by means of providing the facile preparation, easy magnetic separation, high adsorption, and simple regeneration. (C) 2017 Elsevier B.V. All rights reserved.