Photothermal activation of peroxydisulfate using iron nanoparticles/MXene@polyurethane sponge module for treatment of landfill leachate: From lab to pilot scale

Treatment of landfill leachate and recovery of recycled water in photothermal activation of peroxydisulfate (PDS) process using iron nanoparticles/MXene-coated polyurethane sponge module (Fe NPs/MXene@PU) were investigated from lab to pilot scale for the first time. In the module preparation process, nanoscale zero-valent iron (NZVI) and iron oxides were in situ generated on Ti3C2 MXene surface. Fe NPs/MXene@PU module reached the 147.7 degrees C interfacial temperature due to the synergistic effect of MXene and in-situ generated Fe NPs. Sulfate radical (SO4 center dot-) and hydroxyl radical (HO center dot) were generated in photothermal activation of PDS process. Under optimized reaction conditions, almost complete removal of chemical oxygen demand (COD), nitrate nitrogen (NO3-), ammonia nitrogen (NH3-N) and total phosphorus (TP) of landfill leachate was achieved after about 40 d pilot-scale experiment in the open air. The recycled water collected by natural condensation was also purified, which contained ultralow concentrations of COD, NH3-N, NO3-, TP and heavy metals and met the discharge limits of various countries. This study provides an eco-friendly and energy-efficient technology for treatment of landfill leachate and recovery of recycled water.

Automated summary

The study investigated the treatment of landfill leachate and recovery of recycled water using Fe NPs/MXene@PU module, achieving almost complete removal of COD, nitrate nitrogen, ammonia nitrogen, and total phosphorus. Recycled water purification met discharge limits of various countries, providing an eco-friendly and energy-efficient technology.