Enhanced Phosphorus Recovery from Wastewater via 3D-Printed Graphene Capacitive Electrodes and CDI-Assisted Electric Flocculation

Phosphorus, a finite and essential nutrient, necessitates sustainable management practices to ensure its long-term availability. Achieving efficient phosphorus recovery from wastewater is crucial for promoting sustainable phosphorus utilization. However, the low phosphorus concentration and presence of interfering ions in wastewater pose significant challenges to phosphorus recovery. This study proposes a novel approach for enhanced phosphorus recovery through a combined strategy of capacitive deionization (CDI) and electric flocculation, leveraging 3D printed graphene capacitive electrodes with selective phosphorus adsorption capabilities.

The project aims to:

1. Develop high-performance graphene 3D printing inks and construct tunable 3D high-capacitance adsorption electrode materials with precise control over pore structure and surface properties.
2. Screen and optimize iron-based metal-organic frameworks (MOFs) for selective phosphate adsorption and integrate them into the electrode materials.
3. Establish a comprehensive understanding of the correlation between the 3D structure of the electrodes and the effective exposure of phosphorus selective adsorption sites, ultimately influencing the overall phosphorus adsorption efficiency.
4. Investigate the mechanism of phosphate mass transfer within the electrode structure, including the impact of electrode pore construction on surface utilization and phosphate diffusion.
5. Develop an electrochemical regulation strategy for phosphate adsorption and desorption using the capacitive electrodes, aiming to optimize the efficiency and economics of phosphorus recovery from wastewater.
6. Analyze the impact of different water conditions on the phosphorus precipitation fraction and effective phosphorus content during the electroflocculation process.
7. Conduct a comprehensive evaluation of the economic viability and operational stability of the CDI-assisted electroflocculation phosphorus recovery technology.

Successful implementation of this project will establish innovative technologies and principles for the efficient recovery of phosphorus from wastewater, contributing to sustainable resource management and environmental protection.