Armor-Structured Interconnected-Porous Membranes for Corrosion-Resistant and Highly Permeable Waste Ammonium ResourceRecycling

Ammonium recovery from wastewater by gas-permeablemembranes is promising but suffers from the tradeoffbetween membranestability and permeability under harsh operating conditions. Chemical-resistantmembranes display modest permeability due to the poor solubility andprocessibility; chemically active membranes are easier to be endowed withbetter permeability however hinder by instability. To resolve such a problem, wecleverly design a novel membrane configuration via one-step solution-electrospinning, with the chemical-active component (low-strengthfluorinepolymer) as the inner skeleton to construct interconnected porous structuresand the chemical-resistant component (high-strengthfluorine polymer) as theouter armor to serve as a protective layer. Due to the significantly enhanced masstransfer coefficient, the interconnected-porous armor-structured membraneexhibited much higher permeability for NH4+-N recovery, which was 1.4 and5 times that of the traditional PTFE membrane and PP membrane, respectively. Through long-term intermittent and consecutiveexperiments, the reusability and durability of the armor-structured nanofibrous membrane were verified. When treating actualhoggery wastewater with complicated water quality, the armor-structured nanofibrous membrane also displayed robust stableperformance with excellent antiwettability. The mechanisms of membrane formation, corrosion resistance, and mass transfer werediscussed in detail

Automated summary

A novel membrane configuration is cleverly designed to achieve high permeability and stability for ammonium recovery. The armor-structured nanofibrous membrane exhibits excellent performance in treating wastewater with complicated water quality due to its high mass transfer coefficient.