Centrifugal Spinning of Lignin Amine/Cellulose Acetate Nanofiber for Heavy Metal Ion Adsorption

Abstract

This study presented the lignin amine/cellulose acetate (LA/CA) nanofibers prepared by centrifugal spinning for heavy metal ion adsorption. First, lignin alkali is modified by Mannich reaction to prepare lignin amine with amino content of 16 mmol/g, and then the lignin amine was mixed with cellulose acetate to spin LA/CA nanofibers by centrifugal spinning. The effects of spinning parameters and lignin amine content on LA/CA nanofibers morphology were discussed. The optimum performing LA/CA nanofibers with the highest lignin amine content (1.6 wt.%) and the smallest average diameter (756 nm) were obtained when the spinneret rotating speed was about 6000 rpm, collection distance of 15 cm and spinneret hole diameter of 0.16 mm at room temperature. The obtained optimum LA/CA nanofibers were used to adsorb Cu(II) and Co(II) ions, and the influence of temperature, absorb time and initial pH of adsorption system on the adsorption capacity of the nanofibers were analyzed. Furthermore, the adsorption behavior of heavy metal ions Cu(II) and Co(II) was investigated. The results showed that the LA/CA nanofibers presented a quite high adsorption selectivity for Cu(II), the adsorption rates of LA/CA nanofibers to Cu(II) and Co(II) were mainly controlled by chemical adsorption and the adsorption mode was single molecular layer adsorption.