Investigation of Conditions in the Simultaneous Removal of Heavy Metals from Industrial Wastewater Using Adsorption Process

The removal of heavy metals from industrial wastewaters is an important issue due to their high toxicity. In this research, the conditions of simultaneous removal of heavy metals from industrial wastewater (Khark Island petrochemical wastewater as a case study) have been investigated. By testing of some samples, the quality of wastewater was analyzed. The results showed a high amount of organic matters in wastewater which even after the treatment processes are not removed completely. Then, to reduce the heavy metals in the wastewater, a method based on adsorption using activated carbon was investigated. The activated carbon was made from walnut shell. After the synthesis of activated carbon and evaluation of its adsorption characteristics, some tests were carried out of using samples of petrochemical wastewater. The considered absorption parameters were temperature, pH, the amount of absorbent and the adsorption time. The results showed that pH = 6 has the best performance on heavy metals removal. Based on the results, the equilibrium time for lead, copper, chrome was obtained 60 minutes while this value for nickel was equal to 300 minutes. The results also showed that the increase in temperature had an increase in the adsorption efficiency. Finally, the result showed that the activated carbon concentration equal 18g/L wastewater caused the best in heavy metals removal.