Electrospun nanofibrous polylactide/chitosan mats for the filtration of silver ions

We developed biodegradable nanofibrous polylactide/chitosan membranes for the filtration of heavy metal ions. Polylactide and chitosan were first separately dissolved in trifluoroacetic acid. The solutions were then mixed and electrospun into nanofibrous membranes via an electrospinning process. The morphology of the spun nanofibers was examined using scanning electron microscopy. The average diameter of the electrospun nanofibers ranged from 419 to 695 nm. The metal removal capability of nanofibrous polylactide/chitosan membranes was measured and compared with that of bulk chitosan. The influence of various process conditions on metal removal capability was also examined. The experimental results suggested that the electrospun nanofibrous polylactide/chitosan membranes exhibit good heavy metal ion uptake capabilities. The metal removal capability of nanofibrous membranes increased with the initial metal ion concentrations and the pH value, while it decreased with the temperature and the filtering rate of the solutions. Furthermore, the electrospun membrane could be reused after the recovery process. The empirical results in this study suggested that electrospun nanofibrous polylactide/chitosan membranes can be good candidates for the removal of heavy metal ions.