Easy-handling carbon nanotubes decorated poly(arylene ether nitrile)@tannic acid/carboxylated chitosan nanofibrous composite absorbent for efficient removal of methylene blue and congo red

Abstract

Fabrication of highly efficient adsorption and easy-handling absorbent is promising for removal of dyes from wastewater, but it was still a big challenge. In this study, a novel polymer nanofibrous composite absorbent was designed by the decoration of acidified MWCNTs on polydopamine-modified poly(arylene ether nitrile) nanofibrous membrane and following co-deposition of tannic acid/carboxylated chitosan. The structure and composition of as-prepared nanofibrous composite absorbent were confirmed by SEM, FTIR, XPS, and TGA. The congo red (CR) and methylene blue (MeB) were applied as probe dyes to evaluate the adsorption capacity of nanofibrous composite absorbent (With the average pore diameter of 19.21 nm) for cation and anion dyes. It was found that the adsorption capacity of MeB and CR at the optimum pH could reach 633 and 589 mg/g in 300 min, respectively. The adsorption process of MeB and CR followed the Langmuir adsorption model and pseudo-second-order model. Moreover, the nanofibrous composite absorbent exhibited easy-handling property and good regeneration ability, showing the potential application for the efficient adsorption of various dyes from wastewater. • A novel polymer nanofibrous composite absorbent was designed. • Decoration of acidified MWCNTs on PDA/PEN nanofibrous mat and codeposition of tannic acid/carboxylated chitosan was applied. • The maximum adsorption capacities for MeB and CR could reach 633 and 589 mg/g at the optimum pH values, respectively. • The nanofibrous composite absorbent exhibited good regeneration ability and easy-handling property.