Catalytic wastewater dephosphorization for phosphorus recycling to fertilizers

Bromide-induced peroxymonosulfate (PMS) activation was employed for selective degradation of N-containing organophosphine in wastewater into phosphates to be recycled to fertilizers. The selective degradation of N-containing phosphonates was activated by triggering of the electron transfer process between the N-containing phosphonates and PMS, and realized by bromine active species (HBrO). The degradation rate of N-containing phosphonates in the PMS/Br - system is highly relevant to some specific physicochemical properties of the phosphonates. For real glyphosate-containing wastewater, PMS/Br - exhibited excellent catalytic activity with 67.8% decrease in chemical oxygen demand, 48.8% reduction in total organic carbon, and formation of 350 μmol/L of o-PO 4 3- in 90 min, which was further transformed into a phosphate fertilizer of struvite at an 84.9% yield. This study not only demonstrates an affordable and efficient method for wastewater dephosphorization, but also offers a simple and useful way to recover phosphorus resources from wastewater to a valued product. • Perxymonosulfate (PMS)/Br - can make N-containing organophosphine degraded into phosphate. • Phosphate was transformed into a phosphatic fertilizer by struvite precipitation. • Electrons transfer from pollutants to PMS is a prerequisite for selective degradation.