Department of Environmental Engineering, School of Environment, College of Engineering, University of Tehran, Tehran, Iran


BACKGROUND AND OBJECTIVES: Rainwater in the city of Tehran is regarded as a freshwater source; however, because of highly polluted air conditions, the rainwater quality could be seriously affected. Therefore, the treatment of it could be an attractive topic for assessment. The purpose of the present study was to treat Tehran rainwater by employing photoelectrocatalytic methods as one of the most powerful treatment methods. Also, this study aimed to find an easy laboratory procedure to create various redox environments and to assess a protocol for the release of metals.
METHODS: The photoelectrocatalytic process was achieved by using a photocatalyst (Titanium dioxide) as the photoanode for the treatment of Tehran rainwater.  Sodium ascorbate was used as a reducing modifier to assess the effect of various redox potentials on the performance of the photoelectrocatalytic process.
FINDING: The positive redox potential, the 6 centimeter gap, and the sodium chloride concentration of o.65 g/L resulted in a considerable increase of the chemical oxygen demand, iron, manganese and lead removals. On the other hand, the negative redox potential, the 12 cm gap, and the sodium chloride concentration of o.65 g/L led to a noticeable increase in the removal of zinc. By employing the speciation and Pourbaix diagrams, the removal mechanisms of the PEC process were investigated. Chemical oxygen demand, iron and manganese by oxidation, lead, zinc and cadmium by precipitation were removed. Also, based on the cluster analysis, it was found that redox potential, dissolved oxygen and pH had a strong relationship.
CONCLUSION: This work provided evidence that the redox potential could be regarded as a critical parameter helping to better estimate the risks associated with the polluted sites.


Main Subjects


This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit:

Su, X.; Kushima, A.; Halliday, C.; Zhou, J.; Li, J.; Hatton, T.A., (2018). Electrochemically-mediated selective capture of heavy metal chromium and arsenic oxyanions from water. Nat. Commun., 9(1): 1-9 (9 pages).


International Journal of Human Capital in Urban Management (IJHCUM) welcomes letters to the editor for the post-publication discussions and corrections which allows debate post publication on its site, through the Letters to Editor. Letters pertaining to manuscript published in IJHCUM should be sent to the editorial office of IJHCUM within three months of either online publication or before printed publication, except for critiques of original research. Following points are to be considering before sending the letters (comments) to the editor.

[1] Letters that include statements of statistics, facts, research, or theories should include appropriate references, although more than three are discouraged.

[2] Letters that are personal attacks on an author rather than thoughtful criticism of the author’s ideas will not be considered for publication.

[3] Letters can be no more than 300 words in length.

[4] Letter writers should include a statement at the beginning of the letter stating that it is being submitted either for publication or not.

[5] Anonymous letters will not be considered.

[6] Letter writers must include their city and state of residence or work.

[7] Letters will be edited for clarity and length.