A green method to synthesize flowerlike Fe(OH)3 microspheres for enhanced adsorption performance toward organic and heavy metal pollutants

J Environ Sci (China). 2018 Nov:73:47-57. doi: 10.1016/j.jes.2018.01.010. Epub 2018 Feb 3.

Abstract

Dyestuffs and heavy metal ions in water are seriously harmful to the ecological environment and human health. Three-dimensional (3D) flowerlike Fe(OH)3 microspheres were synthesized through a green yet low-cost injection method, for the removal of organic dyes and heavy metal ions. The Fe(OH)3 microspheres were characterized by thermal gravimetric analysis (TGA), Fourier transform infrared (FT-IR), and transmission electron microscopy (TEM) techniques. The adsorption kinetics of Congo Red (CR) on Fe(OH)3 microspheres obeyed the pseudo-second-order model. Cr6+ and Pb2+ adsorption behaviors on Fe(OH)3 microspheres followed the Langmuir isotherm model. The maximum adsorption capacities of the synthesized Fe(OH)3 were 308, 52.94, and 75.64mg/g for CR, Cr6+, and Pb2+ respectively. The enhanced adsorption performance originated from its surface properties and large specific surface area of 250m2/g. The microspheres also have excellent adsorption stability and recyclability. Another merit of the Fe(OH)3 material is that it also acts as a Fenton-like catalyst. These twin functionalities (both as adsorbent and Fenton-like catalyst) give the synthesized Fe(OH)3 microspheres great potential in the field of water treatment.

Keywords: Adsorption; Contaminant; Green method; Water treatment.

MeSH terms

  • Adsorption
  • Ferric Compounds / chemistry*
  • Metals, Heavy / chemistry*
  • Microspheres*
  • Spectroscopy, Fourier Transform Infrared
  • Water Pollutants, Chemical / chemistry*
  • Water Purification / methods*

Substances

  • Ferric Compounds
  • Metals, Heavy
  • Water Pollutants, Chemical
  • ferric hydroxide