One-dimensional magnetic chains for methylene blue removal

Adsorption is a promising method for the treatment of wastewater from the dyestuff industry due to its simplicity, high efficiency, low energy consumption and no secondary pollution. The capacity to separate adsorbents in a timely and efficient manner is a crucial factor in industrial applications. One-dimensional magnetic chains modified with polydopamine and in situ generated Ag nanoparticles (MC@PDA-Ag) were fabricated as highly regenerable adsorbents for methylene blue (MB). The magnetic chains were characterized by scanning electron microscopy, thermogravimetric analysis, Fourier transform infrared spectroscopy, nitrogen adsorption/desorption, X-ray photoelectron spectrometry, X-ray diffraction and magnetometry. The adsorption and catalytic degradation of MB by the materials were investigated. The regeneration capacity of MC@PDA-Ag was also evaluated. The specific saturation magnetization of MC@PDA-Ag is 38.2 emu g^-1. The adsorption capacity of MC@PDA-Ag remained 76% of the initial value after 12 cycles of adsorption and elution. The novel adsorbents, which integrate adsorption and catalytic degradation, are anticipated to facilitate the development of magnetic adsorption materials for the remediation of dye pollution.