Feasibility Study of Using Adsorbent Plants to Remove Heavy Metals from Wastewater of Petrochemical Industry (Razi Case Study of Tehran)

Background & objectives: Since many plants have high efficiency in absorbing heavy elements, the use of phytoremediation is of great importance. The purpose of this study is to identify native plants that absorb heavy metals. Also, the possibility of using them in phytoremediation technology in soils contaminated with heavy metals (around the petrochemical industry of Razi fertilizer in Tehran province) was investigated according to the transfer factor. Methods: This is a library and laboratory research, in which, first sampling of wastewater and plants contaminated with sewage of Razi fertilizer petrochemical industry was done. Secondly, the concentration of heavy elements of lead, zinc and cadmium was measured. Then, healthy plants which were not contaminated with the wastewater of Rzai fertilizer petrochemical industry were exposed to the wastewater of this industry and the transfer factor was calculated for all three elements. Results: The results showed that Achillea willhelmsii, Stipa barbata, and Aconthophyllum microcephallam had the highest concentration of heavy metals uptake with concentrations of 103.7, 237.3 and 0.9 mg / kg, for lead, Zinc and cadmium respectively and are good options for refining soil in the area. Heavy metal transfer factor was also higher in Aconthophyllum microcephallam, Amaranthus retrofiexus and Achillea willhelmsii compared to others. Conclusion: The aerial parts of plants had a great ability to absorb heavy elements compared to their roots. Adsorption concentration and transfer factor of heavy elements absorbed by healthy plants and contaminated with wastewater were different. Healthy plants had a high ability to absorb heavy elements.