Adsorption of methylene blue from aqueous solution using polyacrylonitrile based nanofibrous composites

Abstract

In present investigation, Polyacrylonitrile yarn (PAN) waste nanofibrous composites were prepared using Graphene Oxide (GO), Multiwall Carbon Nanotubes (MWCNTs), Carboxylic group functionalized multiwall carbon nanotubes (COOH-MWCNTs) and Hydroxylic group functionalized Multiwall carbon nanotubes (OH-MWCNTs). These nanofibrous composites were produced by electro spinning technique and used as an adsorbent for removal of methylene blue dye from aqueous solution. The physical, chemical and thermal properties of the prepared nanofibrous composite mats were analyzed by Scannig electron micros copy (SEM), Fourior transform infrared spectroscopy (FT-IR), FT-Raman, X-ray diffractometer (XRD) and Thermogravimetric analyzer (TGA). Effects of parameters such as adsorbent dosage, pH and initial concentration on adsorption of methylene blue have been studied. The batch experiment was carried out for the removal methylene blue dye by placing 50 mg of nanofibrous composite mat into 50 ml of 10 mg / L methylene blue dye solution. The colour removal was measured using the UV- Vis spectrophotometer. newlineThe pH of the medium is very crucial factor that may influence the action of reactive sites on the adsorbent surface. The effect of and#1088;H on the adsorption of methylene blue was studied with pH range from 3 to 11 using constant dye concentration (10 mg / L) and constant adsorbent weight (50 mg) for 6 hours reaction time. The basic pH may enhance the anionic site on the nanofibrous composite mat surface and it leads to electrostatic interaction between the ionic site on the nanofibrous composite surface and the methylene blue dye molecular structure. iv newline newline