Cobalt oxide loaded graphitic carbon nitride as adsorptive photocatalyst for tetracycline removal from aqueous solution

Chemosphere. 2019 Mar:218:169-178. doi: 10.1016/j.chemosphere.2018.11.111. Epub 2018 Nov 17.

Abstract

The treatment of antibiotic-containing wastewater is of great importance due to the potential threats of antibiotics to human and the ecosystem. We reported the preparation of cobalt oxide loaded graphitic carbon nitride (CoO/g-C3N4) by an impregnation-calcination method for tetracycline (TC) removal from aqueous solution. The developed CoO/g-C3N4 exhibited high adsorption capacity and fast adsorption kinetic for TC due to the complexation of TC with surface loaded CoO. In particular, 7%CoO/gC3N43 sample presented a maximum TC adsorption capacity of 391.4 mg g-1. It was found that Langmuir and pseudo-second order kinetic models fitted TC adsorption process well. Further photocatalytic studies showed that CoO loaded g-C3N4 was active for TC photodegradation, although the photocatalytic reaction rate constant was lower than that of native g-C3N4. CoO nanoparticles loading on g-C3N4 played the major role of adsorption sites rather than cocatalyst for photocatalysis. We believe that the developed CoO/g-C3N4 could be a potential adsorptive photocatalyst for antibiotic pollutants removal from wastewater.

Keywords: Adsorption; Antibiotic; Cobalt oxide; Graphitic carbon nitride; Photocatalysis.

MeSH terms

  • Adsorption
  • Anti-Bacterial Agents / isolation & purification
  • Catalysis
  • Cobalt / chemistry*
  • Graphite
  • Light
  • Nitriles / chemistry*
  • Oxides / chemistry*
  • Photolysis*
  • Tetracycline / isolation & purification*
  • Wastewater / chemistry
  • Water
  • Water Pollutants, Chemical / analysis
  • Water Pollutants, Chemical / isolation & purification*

Substances

  • Anti-Bacterial Agents
  • Nitriles
  • Oxides
  • Waste Water
  • Water Pollutants, Chemical
  • Water
  • Cobalt
  • cyanogen
  • Graphite
  • Tetracycline
  • cobalt oxide