Robust polymeric hydrogel using rod-like amidodiol as crosslinker: Studies on adsorption kinetics and mechanism using dyes as adsorbate

Abstract

Herein, we report the preparation of robust polyacrylic acid hydrogel using rod-like amidodiol as physical crosslinker. Polyacrylic acid-amidodiol hydrogels were characterized for its chemical structure, rheology, swelling, diffusion, and adsorption properties. Kinetics and mechanism of adsorption were investigated by UV-visible spectroscopy using dyes such as rhodamine 6G and methylene blue as adsorbate. Results suggested pseudo second-order kinetics of multilayer adsorption and hydrogel could retain its shape even after swelling. Effect of amidodiol on the adsorption of dyes was investigated. Extent of interaction between adsorbate-adsorbate and adsorbent-adsorbate was studied using Gile's model. The generated results may provide a low cost simple technology for developing robust polymeric hydrogel adsorbent. The adsorption characteristics results can be exploited for setting up pilot plant adsorbent for the removal of such organic toxic materials. Finally, we have demonstrated its application for the removal of dyes from waste water collected from textile and paper industries.