Khona P. Maziya, Mbongiseni L. Dlamini, Heidi L. Richards
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引用次数: 0
Abstract
In this study, glutamic acid modified graphene oxide (GG-PVA) aerogels were fabricated through a simplistic sol gel and freeze-drying process utilizing polyvinyl alcohol (PVA) as a cross-linker. The aerogels were extensively explored in the abatement of methylene blue (MB) dye from aqueous solutions. Successful synthesis of the aerogels was confirmed by field emission scanning electron microscopy (FESEM), Brunauer-Emmett-Teller (BET), Fourier transform infrared (FTIR) and Thermogravimetric analysis (TGA), Yielding relatively homogeneous honeycomb and porous surfaces, with 3.4326 m2 g−1 surface area and high thermal stability. The MB removal followed monolayer adsorption on the homogeneous surfaces of the GG-PVA, thus defined by the Langmuir Isotherm model, with a maximum adsorption capacity (qmax) of 121.95 mg g−1. Maximum adsorption of the MB was favored by near neutral to alkaline conditions, reaching 88.4% efficiency and equilibrium reached in the first 30 min of the adsorption process. The kinetics of the MB removal followed the pseudo-second order model. Furthermore, thermodynamic studies revealed endothermic (ΔHo = 80.598 kJ mol−1) and spontaneous (ΔGo = -8.219 kJ mol−1) nature of the adsorption process. The overall adsorption process was principally influenced by the charge and size of the MB molecule, as well as the surface-active sites, porosity, and charge of aerogels among other factors. This study underscores the facile synthesis and effective application of GG-PVA aerogels in MB dye removal, highlighting their potential as effective materials for textile wastewater remediation.
期刊介绍:
Journal of Polymer Research provides a forum for the prompt publication of articles concerning the fundamental and applied research of polymers. Its great feature lies in the diversity of content which it encompasses, drawing together results from all aspects of polymer science and technology.
As polymer research is rapidly growing around the globe, the aim of this journal is to establish itself as a significant information tool not only for the international polymer researchers in academia but also for those working in industry. The scope of the journal covers a wide range of the highly interdisciplinary field of polymer science and technology, including:
polymer synthesis;
polymer reactions;
polymerization kinetics;
polymer physics;
morphology;
structure-property relationships;
polymer analysis and characterization;
physical and mechanical properties;
electrical and optical properties;
polymer processing and rheology;
application of polymers;
supramolecular science of polymers;
polymer composites.