Remediation of metal contamination by electrokinetics coupled with electrospun polyacrylonitrile nanofiber membrane

Polyacrylonitrile nanofiber (PANN) membrane fabricated by electrospinning was adopted for the first time as the reactive medium to remove metal ions from the contaminated soils. Characteristics of metal ion remediation by electrokinetics/PANN permeable reactive barrier (EK/PANNPRB) were investigated. Applied voltages, initial metal ion concentrations and soil pH were changed to explore the adsorb and complexion behavior of PANN with metal ions. The results showed EK/PANNPRB had higher removal efficiency than EK without PRB. The metal ion removal efficiencies by PANNPRB decreased when the applied voltage was increased. The lower the initial metal ion concentrations and soil pH, the better were the removal rates. At the applied voltage of 25 V, metal ion concentrations of 5, 10, and 100 mg L−1 and pH of 1.2, the removal rates of Zn2+, Fe3+, and Ca2+ were 99.15%, 98.03%, and 99.73%, respectively. The results indicated that EK/PANNPRB system was suitable for the remediation of soil contaminated by metal ions with removal rates much higher than those exhibited by the EK system without modified PRB.