Electrochemical crystallization for recovery of phosphorus and potassium from urine as K-struvite with a sacrificial magnesium anode

Declining earth resources, rising ore cost and increasing pollution are calling for recycling of wastewater in the context circular economy. In particular, urine is a potential source phosphorus (P) potassium (K), yet currently available methods P K recovery limited efficiency. Here, we designed an electrochemical crystallization system using sacrificial magnesium anodes to recover form K-struvite (MgKPO4·6H2O) from simulated at low (P/K = 0.25) high 0.6) phosphate levels, respectively. Results show optimal recoveries 88.5% 35.4% rod-shaped 3.5 mA/cm2, though higher current density reduced due side reactions pH increase. Seeding prefabricated struvite crystals 1.6 g/L into enhanced by 14.7% 23.7% compared control group. Overall, our findings that promising fertilizers.