biostudies-literatureZhan ZShenzhen Science and Technology Innovation CommissionNatural Science Foundation of Guangdong Province (Guangdong Natural Science Foundation)100https://www.ebi.ac.uk/biostudies/studies/S-EPMC12775475biostudies-literatureUnknown17(1)Lime-based precipitation, though widely adopted for wastewater phosphorus (P) removal, suffers from surface passivation. The passivation layer inhibits Ca²⁺ release, forcing excessive dosing while yielding low-quality sludge and effluent with elevated hardness and pH. Limestone, despite its economic and environmental benefits, exhibits limited efficacy under fluctuating alkalinity. Here, we develop a limestone-integrated electrochemical system that spatially decouples the dissolution and precipitation reactions. By strategically positioning limestone at the acidic anode, we ensure sustained Ca²⁺ release without passivation, while cathodic alkalinity enables efficient P recovery (85.7%). The system produces high-purity products (15.2 wt% P) at low energy consumption (14.8 kWh kg P^-1) and delivers superior effluent quality. Beyond its robustness and capacity flexibility over long-term operation, the electrochemical strategy reduces overall costs by 73.2% and carbon emissions by 29.1%, positioning it as a cost-effective and sustainable alternative to traditional lime-based wastewater treatment with remarkable passivation resistance and resource recovery efficiency.Nature communicationsSpatially decoupled electrochemical strategy for lime passivation prevention and sustainable phosphate recovery.PMC12775475JCYJ20250604144607011JCYJ202308070934050112023A1515110152Lv JLi WLiu JLei YLiu CZhan ZfalseSpatially decoupled electrochemical strategy for lime passivation prevention and sustainable phosphate recovery.Lime-based precipitation, though widely adopted for wastewater phosphorus (P) removal, suffers from surface passivation. The passivation layer inhibits Ca²⁺ release, forcing excessive dosing while yielding low-quality sludge and effluent with elevated hardness and pH. Limestone, despite its economic and environmental benefits, exhibits limited efficacy under fluctuating alkalinity. Here, we develop a limestone-integrated electrochemical system that spatially decouples the dissolution and precipitation reactions. By strategically positioning limestone at the acidic anode, we ensure sustained Ca²⁺ release without passivation, while cathodic alkalinity enables efficient P recovery (85.7%). The system produces high-purity products (15.2 wt% P) at low energy consumption (14.8 kWh kg P^-1) and delivers superior effluent quality. Beyond its robustness and capacity flexibility over long-term operation, the electrochemical strategy reduces overall costs by 73.2% and carbon emissions by 29.1%, positioning it as a cost-effective and sustainable alternative to traditional lime-based wastewater treatment with remarkable passivation resistance and resource recovery efficiency.2026-01-01T00:00:00Z2026 Jan2026-06-09T05:30:31.512Z2026-06-09T03:07:53.303ZS-EPMC127754754149504010.1038/s41467-025-67911-1