A review of methods for removing heavy metal from aqueous media

Document Type : Review Article


1 Chemical and Petroleum Engineering Department, Sharif University of Technology, Tehran, Iran.

2 Chemical Engineering Department, Sahand University of Technology, Tabriz, Iran.


The present paper briefly describes heavy metals from various aspects, the sources of production and the negative effects of these metals on human health, the standards and regulations of various agencies to comply with the permissible limits and finally, it also explores the methods of purification, separation and removal of these elements.
Regarding treatment methods, a wide range of processes and disadvantages and advantages of each of the old types to the new technologies has been investigated, including chemical precipitation, coagulation-flocculation, flotation, ion exchange, electrochemical treatment, membrane filtration and adsorption.
In this regard, absorption is considered as a simple but efficient approach, and has been specifically addressed and sorbents have been studied including active carbon, carbon nanotubes, graphene oxides and biosorbents.
Today, nanoscale materials have shown significant applications in the treatment of aquatic environments, due to their unique features such as high surface area, large active sites and high absorption capacity. In this regard, magnetic nanoparticles of iron oxides are considered as cost-effective, high-efficiency and environmentally friendly adsorbents.


Main Subjects

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Volume 5, Issue 3
October 2018
Pages 855-874
  • Receive Date: 22 August 2017
  • Revise Date: 02 May 2018
  • Accept Date: 10 March 2018
  • First Publish Date: 23 September 2018