Adsorption characteristics of ammonium ion onto hydrous biochars in dilute aqueous solutions

Bioresour Technol. 2019 Jan:272:465-472. doi: 10.1016/j.biortech.2018.10.064. Epub 2018 Oct 26.

Abstract

This research aims at studying the characteristics of ammonium adsorption onto hydrous bamboo biochar. Results showed that pH played the most important role in ammonium adsorption. High ionic strength enhanced the ammonium adsorption capacity of bamboo biochar. Ammonium adsorption was exothermic and spontaneous. FTIR results showed shift, disappearance, or appearance of specific functional groups on the bamboo biochar surface. Surface precipitation and complex formation contributed to the adsorption of ammonium onto hydrous bamboo biochar. Biochar can be an effective adsorbate for ammonium removal from water. Additionally, the formation of nitrogen containing precipitates on the biochar surface, potentially, leads to the in-situ synthesis of slow-release fertilizer.

Keywords: Ammonium; Biochar; Heterogeneous adsorption; Slow-release fertilizer; Surface complexation; Surface precipitation.

MeSH terms

  • Adsorption
  • Ammonium Compounds / chemistry
  • Ammonium Compounds / isolation & purification*
  • Charcoal / chemistry*
  • Indicator Dilution Techniques
  • Nitrogen / chemistry
  • Solutions / chemistry
  • Water / chemistry

Substances

  • Ammonium Compounds
  • Solutions
  • biochar
  • Water
  • Charcoal
  • Nitrogen