The objective of this study was to establish a suitable chemical process to recover magnesium compounds from Dead Sea water using a selective precipitation process. The recovered magnesium hydroxide (Mg(OH)2) and magnesium chloride (MgCl2) are applicable for wastewater treatment processes since they can effectively remove total suspended solids (TSS) and chemical oxygen demand (COD). Magnesium salts recovered from Dead Sea water were compared with cationic polyacrylamide (PAM) and inorganic salts, including aluminum sulfate Al2(SO4)3, ferric chloride (FeCl3), and ferrous sulfate (Fe2SO4) to investigate the removal efficiency of TSS and COD from wastewater using a chemical precipitation method by using coagulation and flocculation process. Results show that Mg(OH)2 yielded the highest TSS and COD removal efficiencies of 59 and 57%, respectively, with a wastewater pH of 11.5. MgCl2 yielded lower removal efficiencies of 46 and 44%, respectively; at pH 10.5, lower magnesium concentration doses were needed. The most effective chemical precipitation method for removal involved cationic PAM coagulants, resulting in an 86% reduction in TSS and a 65% reduction in COD. Combining commercial Fe2SO4 and MgCL2 recovered from Dead Sea water reduced up to 90 and 73% of TSS and COD, respectively.

  • Suitable chemical process recovers Mg compounds from Dead Sea (DS).

  • Mg(OH)2 and MgCl2 effectively remove total suspended solids (TSS) and chemical oxygen demand (COD).

  • Mg salts were compared with polyacrylamide, Al2(So4)3, FeCl3, and Fe2SO4 to investigate the removal efficiency of TSS and COD.

  • Mg recovery from DS is a new and novel contribution to this research.

  • This research tackles the unique opportunity to leverage the high concentration of Mg compounds available from DS.

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