Microencapsulated reactor for simultaneous removal of calcium, fluoride and phenol using microbially induced calcium precipitation: Mechanism and functional characterization

J Hazard Mater. 2023 Mar 15:446:130704. doi: 10.1016/j.jhazmat.2022.130704. Epub 2022 Dec 29.

Abstract

Fluoride ions (F-) and phenol in groundwater have become a great hurdle to the pursuit of a healthy drinking water source. This study established a microencapsulated immobilization reactor with Aquabacterium sp. CZ3 for the simultaneous removal of nitrate (NO3--N), calcium (Ca2+), F-, and phenol from groundwater with 100%, 67.84%, 88.67%, and 100% removal efficiencies, respectively. The three-dimensional mesh structure of microcapsules facilitated the transport and metabolism of substances, while their synergistic effect with bacteria promoted the removal of contaminants. F- was removed by co-precipitation to generate Ca5(PO4)3F and CaF2 and adsorption. On one hand, the phenol toxicity promoted the production of extracellular polymers and improved the tolerance of bacteria; on the other hand, the degradation of phenol provided a carbon source for bacteria and promoted the denitrification. The development of microencapsulated immobilized reactor provided a clear mechanism for phenol and F- removal under the microbially induced calcium precipitation (MICP) technique, while providing a valuable solution for the treatment of complex groundwater resources.

Keywords: Defluoridation; Denitrification; Facultative anaerobic MICP; Immobilized reactor; Phenol degradation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bioreactors / microbiology
  • Calcium
  • Denitrification
  • Fluorides*
  • Nitrates / chemistry
  • Phenol* / chemistry
  • Phenols

Substances

  • Phenol
  • Fluorides
  • Calcium
  • Phenols
  • Nitrates