Toktam Shahriari - Faculty of Environment, University of Tehran, Tehran, Iran
Gholamreza Nabi Bidhendi - Faculty of Environment, University of Tehran, Tehran, Iran
Naser Mehrdadi - Faculty of Environment, University of Tehran, Tehran, Iran
Ali Torabian - Faculty of Environment, University of Tehran, Tehran, Iran

In recent decades, enormous use of chromium in different industries as well as water and soil pollution by those industries caused serious concern. Toxic impact of chromium on the growth of plants includes changes in the process of germination and root, stem and leaves’ growth. Chromium also has harmful impact on the plants’ physiological processes such as photosynthesis. On the other hand, iron is one of the essential elements for the growth of plants without which enough chlorophyll would not exist in the cells, consequently; making leaves pale. Melissa officinalis L.is an herb with ۳۰ to ۱۲۰ cm long. This plant is sensitive to iron deficiency. Electrocoagulation is a method to remove heavy metals. One of the advantages of this method is low consumption of power and high efficiency in removing pollutants. In this study chromium removal with ۵۰۰ mg/l concentration from artificial wastewater containing chromium (III) was examined and removal efficiency of ۹۷% was achieved. Here also the impact of pH on efficiency of chromium removal and amount of produced iron was tested and voltage parameter was examined to achieve optimal condition. In regard to efficiency of chromium removal, the optimal pH of tests was ۶ and the amount of iron was ۸.۱۴ mg/l.

chlorophyll, Chromium, Electrocoagulation, Iron, Melissa officinalis L