نويد رستمخاني

Magnesium, is an impurity in zinc leaching solutions an‎d can disrupt the electrowinning process an‎d affect the quality of the final product; in order to improve zinc recovery an‎d product quality it is important to remove magnesium. Among the methods for magnesium removal, Alkaline zinc sulfate precipitation, Concentrate acid pickling, Cooling crystallization, an‎d chemical precipitation can be mentioned. This research has investigated the removal of magnesium from the effluent solution resulting from the alkaline zinc sulfate precipitation process using chemical precipitation with sodium fluoride. Using response surface Central Composite Design (CCD), the effect of parameters including pH, the stoichiometric ratio of sodium fluoride to effluent magnesium, an‎d time has been examined. The analyses have also been performed using ICP (inductively coupled plasma), AAS (atomic absorption spectroscopy), XRD (X-ray diffraction), thermodynamic analysis, an‎d statistical analysis an‎d modeling. The results showed that sodium fluoride can effectively remove magnesium an‎d produce a solid product of suitable quality. The optimal conditions obtained from the optimization for magnesium removal were achieved at pH equal to 7.4, a complete stoichiometric ratio of sodium fluoride to effluent magnesium content (two moles of sodium fluoride reacted with one mole of magnesium), an‎d a reaction time equal to 15 minutes. Under these conditions, the highest magnesium removal efficiency using sodium fluoride was measured at 97 percent. Statistical modeling an‎d thermodynamic analysis also confirmed these results. The solid product obtained in the experiment under optimal conditions was identified using the XRD method an‎d the suitable quality of the solid product was confirmed. In general, fluoride precipitation is an effective method for removing magnesium from zinc leaching effluent solutions, which can contribute to the improvement of the conditions an‎d efficiency of zinc hydrometallurgical processes.

حذف منيزيم، فلورايد سديم، ، تصفيه پساب، ترسيب شيميايي، سولفات روي قليايي

Magnesium removal, Effluent treatment, Chemical precipitation, Sodium flouride

Navid Rostamkhani

Dr. Hossein Aghajani