ᐊ P6-21
Open Readings 2021 • P6-22
P6-23 ᐅ

SYNTHESIS, CHARACTERIZATION AND APPLICATION OF CHITOSAN-CLAY-BASED NANOCOMPOSITES FOR SORPTION OF METALS/RADIONUCLIDES

Karolina Karalevičiūtė1, 2, Galina Lujanienė2, Raman Novikau2, Vidas Pakštas3, Audrius Drabavičius3, Arnas Naujokaitis3

1 Department of Analytical and Environmental Chemistry, Faculty of Chemistry and Geosciences, Vilnius University, Lithuania

2 Department of Environmental Research, Center for Physical Sciences and Technology, Lithuania

3 Department of Characterisation of Materials Structure, Center for Physical Sciences and Technology, Lithuania

[email protected]

Unique properties of chitosan such as biocompatibility, biodegradability, antimicrobial activity and non-toxicity have resulted in an increasing interest of its investigation and widespread application [1]. Chitosan biopolymer is used in various fields: medicine, pharmacy, agriculture, food packaging and cosmetic industry as well as for removal of heavy metals from wastewater [2]. However, chitosan has low water resistance, poor mechanical and thermal properties limiting its usage.

A commonly used way for improving the mechanical and barrier properties of chitosan is to add nanosized reinforcing elements into chitosan chains [3]. The use of clay as an adsorbent is due to the peculiarities of its structure, as well as its economic availability and ubiquity. The trend towards the use of clay has undergone several changes, from its use in its pure form to modifications and combination with other adsorbents. Chitosan-clay nanocomposites have attracted considerable interest because they combine the structure, physical and chemical properties of inorganic and organic materials [4].

The aim of this study was to prepare chitosan – clay nanocomposites with various clay concentrations, in order to identify and characterize the structure of nanocomposites using X-ray diffraction (XRD), transmission electron microscope (TEM) and scanning electron microscopy (SEM) as well as to apply the synthesized nanocomposites for sorption of metals and radionuclides.

In this research, chitosan powder was dissolved in 100 ml of an aqueous solution of acetic acid (1%, v/v), using a magnetic stirring plate at 90 °C and 150 rpm for 1 hours and then cooling the solution to room temperature. Chitosan-clay nanocomposites were obtained by mixing the chitosan with different amounts of clay (0, 5, 10, 15 wt%). The structure morphology and composition of nanocomposites were characterized using X-ray diffraction (XRD), transmission electron microscope (TEM) and scanning electron microscopy (SEM). This investigation let us identify what shapes and size of particles were synthesized. The obtained nanocomposites were applied for the sorption of metals and radionuclides.

[1] Biswas S., Rashid T.U., Debnath T., Haque P. 2020. Application of Chitosan-Clay Biocomposite Beads for Removal of Heavy Metal and Dye from Industrial Effluent,: 1-14. DOI: 10.3390/jcs4010016.

[2] Kusmono, Abdurrahim I. 2019. Water sorption, antimicrobial activity, and thermal and mechanical properties of chitosan/clay/glycerol nanocomposite films, Heliyon 5(8): e02342. DOI: 10.1016/j.heliyon.2019.e02342.

[3] Neji A.B., Jridi M., kchaou H., Nasri M., Dhouib Sahnoun R. 2020. Preparation, characterization, mechanical and barrier properties investigation of chitosan-kaolinite nanocomposite, Polymer Testing 84(October 2019): 106380. DOI: 10.1016/j.polymertesting.2020.106380.

[4] A Neves M. 2016. Development and Characterization of Chitosan-Nanoclay Composite Films for Enhanced Gas Barrier and Mechanical Properties, Food Science & Nutrition 2(1): 1–7. DOI: 10.24966/fsn-1076/100007.