Synthesis of Novel Magnetic Microspheres with Bimetal Oxide Shell for Excellent Adsorption of Oxytetracycline

Abstract

Multifunctional magnetic microspheres (Mag@ZnO–Co3O4) with bimetal oxide shell were synthesized via a facile method. The Mag@ZnO–Co3O4 composite was characterized through a vibrating sample magnetometer, N2 adsorption analysis, Fourier transform infrared spectroscopy, powder X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy analyses. The structural analysis showed that the as-prepared microsphere possessed a mean diameter of 150 nm, a bimetal oxide shell thickness of ∼10.0 nm, and a magnetic core, which endowed it with good dispersibility, strong magnetism, and excellent adsorption property for oxytetracycline (OTC). Several experimental conditions, such as solution pH, adsorption time, OTC concentration, and ionic strength were systematically investigated. The Mag@ZnO–Co3O4 composite exhibited a fast adsorption rate, that is, the equilibrium was reached within 90 min, when the concentration of OTC was between 10 and 30 mg/L. The composite showed favorable performance for the adsorption of OTC in the pH range 5–9. According to the adsorption isotherms and kinetics, the removal of OTC was efficient and obeyed the pseudo-second-order rate equation and Langmuir adsorption model.

Superior Adsorption and Photocatalytic Degradation Capability of Mesoporous LaFeO3/g-C3N4 for Removal of Oxytetracycline

“…These results were associated with the surface properties of 2-LFC and the relationship between the molecular species of OTC and the solution pH. Oxytetracycline had different molecular species under different pH values [8]. OTC was positive charged as solution pH < 3.53 and negative charged as pH > 9.58.…”

“…The photocatalysis can be satisfactory applied for decontamination of natural samples through the photocatalytic degradation of toxic pollutants from complex matrices like river waters and waste waters [6]. Oxytetracycline (OTC) is a broad-spectrum antibiotic commonly applied to aquaculture and veterinary medicine, which is mainly excreted in unchanged and active forms in effluents of surface water [7,8]. Most of OTC cannot be eliminated by biological and traditional treatment processes due to its high stability.…”

Au‐Mediated Composite In2S3–Au–BiVO4 with Enhanced Photocatalytic Activity for Organic Pollutant Degradation

“…Photoluminescence (PL) emission spectroscopy is a useful technique to evaluate the efficiency of photo‐generated charge carrier trapping, migration, and recombination in semiconductor photocatalysts . The PL emission spectra of BiVO 4 , Au–BiVO 4 , In 2 S 3 –BiVO 4 and In 2 S 3 –Au–BiVO 4 were measured and shown in Figure B.…”

“…Photoluminescence (PL) emission spectroscopy is a useful technique to evaluate the efficiency of photo-generated charge carrier trapping, migration, and recombination in semiconductor photocatalysts. [42][43][44] The PL emission spectra of BiVO 4 , Au-BiVO 4 , In 2 S 3 -BiVO 4 and In 2 S 3 -Au-BiVO 4 were measured and shown in Figure 4B. Compared to bare BiVO 4 , In 2 S 3 -BiVO 4 displays weaker PL intensity, due to the formation of heterostructure between In 2 S 3 and BiVO 4 .…”

NiFe2O4@ nitrogen-doped carbon hollow spheres with highly efficient and recyclable adsorption of tetracycline

“…Thus, the application of magnetic adsorbents is an innovative method to resolve environmental problems. [20][21][22] For example, multifunctional magnetic microspheres (Mag@ZnO-Co 3 O 4 ) with bimetal oxide shells have been synthesized and showed excellent adsorption properties for oxytetracycline, with the maximum adsorption capacity of oxytetracycline found to be 128 mg g À1 , 23 and core-shell Fe 3 O 4 @ZIF-8 has been prepared and showed excellent adsorptive capacity for tetracycline (TC) antibiotics. 24 However, there is still a challenge in producing a new generation of separation media magnetic nanocomposites.…”