Removal of methylene blue dyes from wastewater using cellulose‐based superadsorbent hydrogels

Abstract

Superadsorbent cellulose‐graft‐acrylic acid (C‐g‐AA) hydrogels were successfully prepared via free radical polymerization in phosphoric acid solution. Phosphoric acid solution provides a homogeneous reaction system. The C‐g‐AA hydrogels have a porous network inner structure with cellulose as the backbone. The introduced carboxyl groups enable the C‐g‐AA hydrogels with good swelling property (swelling ratio 7327%) and excellent MB adsorption capacity (equilibrium adsorption amount 2197 mg g−1). The dynamic swelling behaviors of the hydrogels were tested, water intake of hydrogels followed a non‐Fickian type diffusion. The effects of mole ratio of AA to cellulose, the pH of adsorption medium and the initial MB concentration on dye adsorption capacity of hydrogels were investigated. The adsorption isotherm and kinetics fit the Langmuir model and the Pseudo‐second‐order model well, respectively. Desorption was carried out in weak acid solution and 70% MB could be removed, suggesting the C‐g‐AA hydrogels had the potential for reuse. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers

Comparative study of PEO and PVA hydrogels for removal of methylene blue dye from wastewater

“…As it is shown above, the photochemically produced PEO hydrogels are less crosslinked than chemically crosslinked PVA, which reflects in a more expanded structure for PEO. Otherwise, at lower pH values, the hydroxyl groups are protonated and, therefore, reducing MB molecules adsorption binding sites …”

Synthesis of semi interpenetrating network hydrogel [(GrA‐Psy)‐cl‐Poly (AA)] and its application for efficient removal of malachite green from aqueous solution

“…Various treatment processes such as ozonation , coagulation , ultrafiltration , oxidation , photocatalytic degradation , and adsorption are applied for dye removal from wastewater, but adsorption is considered as the most efficient method for the removal of dyes from wastewater . In the recent years, extensive research has been undertaken to develop alternative and cost‐effective adsorbents .…”

Kinetic and equilibrium modeling for adsorption of textile dyes in aqueous solutions by carboxymethyl cellulose/poly(acrylamide‐co‐hydroxyethyl methacrylate) semi‐interpenetrating network hydrogel

“…to color various products . It is reported that 2% of total dyes produced in its manufacturing units and 10–20% of dyes used for coloring different products are discharged in effluent water . However, most of the dyes are toxic and carcinogenic.…”

“…may effectively remove low concentration of dyes from water . In recent years, various polymeric hydrogels based on acrylic polymer/copolymers , semi‐ and full‐interpenetrating network (IPN) and natural polymers like chitosan , modified cellulose , alginates were tried for removal of dye from water. Natural polymers are abundant, renewable and biodegradable.…”