Synergistic harmless treatment of phosphogypsum leachate wastewater with iron-rich electrolytic manganese residue and electric field

In the iron-rich electrolytic manganese residue (IREMR) and phosphogypsum leachate wastewater (PLW), there are high levels of Mn2+, NH4+-N, F-, and PO43- pollutants which severely contaminate the surrounding environment. This study focuses on a synergistic and environmentally friendly treatment of PLW using IREMR and an electric field. During the mixed leaching process, with a mass ratio of IREMR to PLW of 1:25, a reaction temperature of 25 degrees C, a leaching pH of 3.0, and a reaction time of 30 min, the concentrations of Mn2+ PO43-, NH4+-N, and F- in the mixed leaching wastewater were measured to be 1235.49 mg/L, 1507.97 mg/L, 700.15 mg/L, and 146.76 mg/L, respectively. In the pollutant precipitation removal process, with a pH of 9.5 in the mixed leaching wastewater, a current density of 10 mA/cm(2), a reaction temperature of 35 degrees C, and a reaction time of 45 min, the removal efficiencies of Mn2+, PO43-, NH4+-N, and F- were found to be 99.81 %, 99.86 %, 58.37 %, and 99.90 %, respectively. The removal mechanism indicates that Mn2+, F-, PO43-, and NH4+-N were primarily eliminated through the formation of Mn(OH)(2), Mn-3(PO4)(2).2H(2)O, CaF2, MnF2, and Mg(NH4)PO4.6H(2)O. This research offers a new approach for the resource utilization and environmentally safe treatment of PLW.

Automated summary

This study focuses on the synergistic and environmentally friendly treatment of phosphogypsum leachate wastewater (PLW) using iron-rich electrolytic manganese residue (IREMR) and an electric field. The results showed that under specific conditions, the concentrations of Mn2+, PO43-, NH4+-N, and F- in the wastewater could be effectively reduced. The removal mechanism involved the formation of various compounds. The research provides a new approach for the resource utilization and environmentally safe treatment of PLW.