Preparation and Adsorption Behavior of Aminated Electrospun Polyacrylonitrile Nanofiber Mats for Heavy Metal Ion Removal

Abstract

Polyacrylonitrile (PAN) nanofiber mats were prepared by electrospinning and they were further modified to contain amidino diethylenediamine chelating groups on their surface via heterogeneous reaction with diethylenetriamine (DETA). The obtained aminated PAN (APAN) nanofiber mats were evaluated for their chelating property with four types of metal ions, namely Cu(II), Ag(I), Fe(II), and Pb(II) ions. The amounts of the metal ions adsorbed onto the APAN nanofiber mats were influenced by the initial pH and the initial concentration of the metal ion solutions. Increasing the contact time also resulted in a monotonous increase in the adsorbed amounts of the metal ions, which finally reached equilibria at about 10 h for Cu(II) ions and about 5 h for Ag(I), Fe(II), and Pb(II) ions. The maximal adsorption capacities of the metal ions on the APAN nanofiber mats, as calculated from the Langmuir model, were 150.6, 155.5, 116.5, and 60.6 mg g(-1), respectively. Lastly, the spent APAN nanofiber mats could be facilely regenerated with a hydrochloric acid (HCl) aqueous solution.

Removal of Lead and Copper Ions from Polluted Aqueous Solutions using Nano-Sawdust Particles

“…As the surface adsorption sites become exhausted, the uptake rate is controlled by the rate at which the adsorbate is transported from the exterior to the interior sites of the adsorbent particles. Then biosorption reached equilibrium as a result of the reduction of available sites which are difficult to be occupied due to repulsive forces between metal ions biosorbed onto the biosorbent surface and the bulk phase [16,21,22]. Figure 6 shows the effect of changing the adsorbent dosage on the biosorption of lead and copper ions onto nano-sawdust over a range from 0.2-2 g. For lead, minimum percentage removal was 53.48% for the dose of 0.2 g and it increased to maximum value 100% for dose of 2 g, whereas, for copper, minimum value was 84.74% for the dose of 0.2 g to maximum value of 98.78% for the dose of 1 g. But the maximum adsorption of copper is attained after the dose 1 g of nano-sawdust, and hence the amount of ions bound to the adsorbent and the amount of free ions remains constant even with further addition of the dose of adsorbent.…”

Application of Fluorescent Label in Polymer Nanofibers

“…The electrospinning is applicable practically to every soluble or fusible polymer. Nevertheless, beside the most common polymer nanofibers, this technique has found an application in the preparation of metal, glass, ceramic, and carbon nanofibers [18,19].…”

Surface modification of electrospun cellulose acetate nanofibers via RAFT polymerization for DNA adsorption

“…These properties of electrospun nanofibers make them good candidates as affinity membranes for filtration, purification and separation processes (Ma, Kotaki, & Ramakrishna, 2005;Zhu, Yang, & Sun, 2011). Surface modification of electrospun nanofibers with specific functional groups is of great interest due to their potential application in filtration/separation, detection and controlled drug release (Chigome, Darko, & Torto, 2011;Fu, Xu, Yao, Li, & Kang, 2009a;Kampalanonwat & Supaphol, 2010;Mahanta & Valiyaveettil, 2011;Wang et al, 2012;Yao, Xu, Lin, & Fu, 2010). Particularly, polymer functionalized nanofibers that can be obtained via living radical polymerization (LRP) techniques may have a high adsorption capacity and strong binding specificity due to their free active groups on nanofiber surfaces (Chigome et al, 2011;Yao et al, 2010).…”