Heterotrophic nitrification and biomineralization potential of Pseudomonas sp. HXF1 for the simultaneous removal of ammonia nitrogen and fluoride from groundwater

Pseudomonas sp. HXF1, a strain capable of heterotrophic nitrification, aerobic denitrification (HNAD), and biomineralization was identified and employed for the simultaneous removal of ammonia nitrogen (NH4+-N) and fluoride (F-). It removed 99.2% of NH4+-N without accumulation of nitrous nitrogen (NO2--N) and nitrate nitrogen (NO3-N), while removed 87.3% of F-. Response surface methodology (RSM) was used to study the best removal conditions for NH4+-N and F-. The results of nitrogen balance experiments with NH4Cl, NaNO2, and NaNO3 as single nitrogen sources and amplification experiments of denitrification genes proved that the bacterial strains may remove NH4+-N through HNAD. The experimental results of Scanning electron microscope (SEM), Xray photoelectron spectroscopy (XPS), and X-ray diffractometer (XRD) indicated that the way of F- removal may be adsorption and co-precipitation. The results demonstrated that the strain HXF1 has great potential in the biological denitrification and F- removal of groundwater.

Automated summary

Pseudomonas sp. HXF1, capable of heterotrophic nitrification, aerobic denitrification, and biomineralization, was employed for the simultaneous removal of ammonia nitrogen and fluoride. The strain showed promising results in the removal of NH4+-N and F-. RSM was used to study the best removal conditions, indicating the potential of strain HXF1 in biological denitrification and F- removal in groundwater.