Adsorption of methylene blue on hemicellulose‐based stimuli‐responsive porous hydrogel

Abstract

A stimuli-responsive porous hydrogel was synthesized from wheat straw hemicellulose using CaCO 3 as the porogen, and its application for the removal of methylene blue was studied. The porous structure of the prepared hydrogel was confirmed by SEM analysis. The effects of pH and polyelectrolyte on the swelling of the hydrogels were discussed, and the porous hydrogels showed excellent sensitivity to pH and salt. The deswelling kinetic study indicated that the hydrogels exhibited rapid shrinking in NaCl aqueous solutions. The methylene blue adsorption on the hydrogels was investigated, and the obtained adsorption data was fitted to the pseudo-first-order, pseudo-second-order and intra-particle diffusion kinetics models, and the pseudo-first-order kinetic model could describe the adsorption process, and the adsorption process of methylene blue on the hydrogels was controlled by external film diffusion. This study reported that the hemicellulose-based porous hydrogel is promising for water treatment.

Hemicellulose-Based Hydrogels Present Status and Application Prospects: A Brief Review

“…The mechanism of the preparation of hydrogels briefly as follows: sulfate anion radical generated from ammonium persulfate deprives of hydrogen from the hydroxyl group of hemicellulose backbone to form alkoxy radicals, resulting in active centers on the hemicellulose to radically initiate polymerization (Peng et al, 2011;Sun et al, 2015). (Cao, Peng, Zhong, & Sun, 2014) and potassium persulfate (KPS) (Maleki, Edlund, & Albertsson, 2015), sodium sulfite (Maleki et al, 2015), AcGGM was materials for thiolation through one-pot synthetic methodology, this reaction realized by the AcGGM-mediated nucleophilic ring-opening reaction of thiobutyrolactone via the activation of the polysaccharide pendant hydroxyl groups.…”

“…Sun and coworkers (Sun et al, 2015), using CaCO 3 as the porogen, prepared the wheat straw hemicellulose based hydrogels, which had high adsorption capacity for methylene blue and smart swelling property. These properties were very significant for wastewater treatment application.…”

Xylan-Modified-Based Hydrogels with Temperature/pH Dual Sensitivity and Controllable Drug Delivery Behavior

“…Hemicellulose, a renewable plant polysaccharide, ranks second to cellulose in terms of lignocellulosic biomass content, and accounts for 1/4 to 1/3 of agriculture residues [16]. Due to the low cost and good biodegradability and biocompatibility, the high value-added utilization of hemicellulose has attracted much attention [17].…”

Graphene Oxide/Polyacrylamide/Aluminum Ion Cross‐Linked Carboxymethyl Hemicellulose Nanocomposite Hydrogels with Very Tough and Elastic Properties

“…Hemicelluloses, especially xylan‐type hemicelluloses, are the second most abundant renewable plant polymer after cellulose in lignocelluloses biomass; it accounts for 30–40 % of agriculture residue . Hemicelluloses can be separated as byproducts from various kinds of lignocellulosic materials and will become a leading chemical resource in the future.…”