Nitrate pollution and its solutions with special emphasis on electrochemical reduction removal

Environ Sci Pollut Res Int. 2023 Jan;30(4):9290-9310. doi: 10.1007/s11356-022-24450-2. Epub 2022 Dec 5.

Abstract

Nitrate pollution has become a serious environmental concern all over the world including in China due to the mismanagement of water resources and human activities. Agricultural runoff and industrial and nuclear waste are among the major sources of nitrate pollution. Consuming nitrate-rich water can cause many chronic diseases including digestive problems, which can lead to many types of cancer and other serious health issues. Denitrification is the natural process for nitrate reduction under aerobic conditions, but it cannot handle an excess of nitrate, so several methods have been adopted for nitrate removal, i.e., biological, chemical, physicochemical, and electrochemical reduction removal. Among all, electrochemical reduction removal is a cost-effective and environmental-friendly process. To obtain the maximal elimination efficiency ideal conditions of current intensity, pH, plate distance, initial nitrate concentration, and type of electrolyte solution should be studied for effective nitrate removal. Electrochemical reduction removal of nitrate involves the transfer of electrons and hydrogenation. Besides an efficient nitrate removal process, electrochemical reduction removal has some drawbacks like sludge formation, low selectivity for nitrogen, and production of brine that limit its long-term implementation. This review focused on nitrate pollution, previous nitrate removal strategies, and essential principles for understanding the mechanism of electrochemical reduction removal and controlling the products of the reaction.

Keywords: Electrochemical reduction removal; Environmental hazards; Nitrate pollution; Nitrate-removing strategies.

Publication types

  • Review

MeSH terms

  • China
  • Denitrification
  • Humans
  • Nitrates*
  • Nitrogen
  • Sewage*
  • Water

Substances

  • Nitrates
  • Sewage
  • Water
  • Nitrogen