Preparation and characterization of novel chitosan-based mixed matrix membranes resistant in alkaline media

In this work, mixed matrix membranes (MMMs) based on chitosan (CS) and different fillers (room temperature ionic liquid [emim][OAc] (IL), metallic Sn powder, layered titanosilicate AM-4 and layered stannosilicate UZAR-S3) were prepared by solution casting. The room temperature electrical conductivit...

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Detalles Bibliográficos
Autores: García-Cruz, Leticia, Casado Coterillo, Clara|||0000-0002-4454-7652, Iniesta Valcárcel, Jesús, Montiel Leguey, Vicente, Irabien Gulías, Ángel|||0000-0002-2411-4163
Tipo de recurso: artículo
Fecha de publicación:2015
País:España
Institución:Universidad de Cantabria (UC)
Repositorio:UCrea Repositorio Abierto de la Universidad de Cantabria
Idioma:inglés
OAI Identifier:oai:repositorio.unican.es:10902/9831
Acceso en línea:http://hdl.handle.net/10902/9831
Access Level:acceso abierto
Palabra clave:Anion-exchange membrane
Chitosan
Mixed matrix membranes
Layered zeolite analogues
Tin
Ionic liquid
Descripción
Sumario:In this work, mixed matrix membranes (MMMs) based on chitosan (CS) and different fillers (room temperature ionic liquid [emim][OAc] (IL), metallic Sn powder, layered titanosilicate AM-4 and layered stannosilicate UZAR-S3) were prepared by solution casting. The room temperature electrical conductivity and electrochemical response in strong alkaline medium were measured by electrochemical impedance spectroscopy and cyclic voltammetry (CV). The ionic conductivity of pure CS membranes was enhanced, from 0.070 to 0.126 mS cm21, for the pristine CS and Sn/CS membranes, respectively, as a function of the hydrophilic nature of the membrane and the coordination state of Sn. This hydrophilic and charge nature was corroborated by water uptake measurements, where only the introduction of IL in the CS membrane led to a water uptake of 3.96 wt %, 20 or 30 times lower than the other membranes. Good thermal and chemical stability in alkaline media were observed by thermogravimetric analyses and X-ray photoelectron spectroscopy analyses, respectively, and good interaction between CS and the fillers observed by X-ray diffraction, scanning electron microscopy and CV. Thus, thin CS-based MMMs (40–139 mm), resistant in high alkaline media, show higher conductivity than pure CS membranes, especially those fillers containing tin, and although the electrochemical performance is lower than commercially available anion-exchange membranes they have potential in pervaporation.