title: Cationic hemicellulose-based hydrogels for arsenic and chromium removal from aqueous solutions.
abstract: In this work the synthesis of hemicellulose-based hydrogels and their application for the removal of arsenic and chromium ions is described. In a first step O-acetyl galactoglucomannan (GGM) was subjected to a transesterification applying glycidyl methacrylate (GMA) for the synthesis of novel GGM macromonomers. Two distinguished and purified GGM fractions with molar mass of 7.1 and 28 kDa were used as starting materials. The resulting GGM macromonomers (GGM-MA) contained well-defined amounts of methacrylate groups as determined by (1)H NMR spectroscopy. Selected GGM-MA derivatives were consecutively applied as a crosslinker in the synthesis of tailored hydrogels using [2-(methacryloyloxy)ethyl]trimethylammonium chloride (MeDMA) as monomer. The swelling rate of the hydrogels was determined and the coherence between the swelling rate and the hydrogel composition was examined. The morphology of the GGM-based hydrogels was analysed by SEM and the hydrogels revealed a high surface area and were assessed in respect to their ability to remove arsenate and chromate ions from aqueous solutions. The presented bio-based hydrogels are of high interest especially for the mining industries as a sustainable material for the treatment of their highly contaminated wastewaters.
authors.affiliation: Process Chemistry Centre, c/o Laboratory of Wood and Paper Chemistry, Åbo Akademi University, Porthansgatan 3, 20500 Åbo/Turku, Finland. Electronic address: ddax@abo.fi.
authors.forename: Daniel
authors.initials: D
authors.lastname: Dax
authors.affiliation: Centro de Biotecnología, Universidad de Concepción, Casilla 160-C, Concepción, Chile; Polymer Department, Faculty of Chemistry, University of Concepción, Casilla 160-C, Concepción, Chile.
authors.forename: María Soledad
authors.initials: MS
authors.lastname: Chávez
authors.affiliation: Process Chemistry Centre, c/o Laboratory of Wood and Paper Chemistry, Åbo Akademi University, Porthansgatan 3, 20500 Åbo/Turku, Finland; Wallenberg Wood Science Center, KTH, The Royal Institute of Technology, 10044 Stockholm, Sweden.
authors.forename: Chunlin
authors.initials: C
authors.lastname: Xu
authors.affiliation: Process Chemistry Centre, c/o Laboratory of Wood and Paper Chemistry, Åbo Akademi University, Porthansgatan 3, 20500 Åbo/Turku, Finland.
authors.forename: Stefan
authors.initials: S
authors.lastname: Willför
authors.affiliation: Centro de Biotecnología, Universidad de Concepción, Casilla 160-C, Concepción, Chile; Facultad de Ciencias Forestales, Universidad de Concepción, Casilla 160-C, Concepción, Chile.
authors.forename: Regis Teixeira
authors.initials: RT
authors.lastname: Mendonça
authors.affiliation: Polymer Department, Faculty of Chemistry, University of Concepción, Casilla 160-C, Concepción, Chile. Electronic address: juliosanchez@udec.cl.
authors.forename: Julio
authors.initials: J
authors.lastname: Sánchez
keywords: Crosslinking; Hemicellulose; Hydrogels; O-Acetyl galactoglucomannan; Polysaccharide; Wastewater treatment