8. Nanocomposites and nanomaterials

Adsorption of copper ions on Thymus serpyllum L. plant for the production of nanocrystalline compound
Kováčová M.1, Baláž M.1, Yankovych H. 1, Casas-Luna M.2, Remešová M.2, Čelko L.2
1 Institute of Geotechnics, Slovak Academy of Sciences, Watsonova 45, 04001 Košice, Slovakia. 
E-mail: kovacovam@saske.sk
2 Brno University of Technology, Central European Institute of Technology, Purkynova 123, Brno, 612 00, Czech Republic

In recent years, research on the mechanisms of biosorption has extended as it is an effective and inexpensive opportunity for the removal of heavy metal ions from the aqueous solutions [1]. Biosorption, as a form of a passive remediation treatment, is mainly based on the affinity between a biosorbent and an adsorbate [2].
The main focus of this study was to determine the best parameters for the adsorption of copper (as one of the heavy metals) on Thymus serpyllum L. plant in a batch mode. This plant has already been used for the efficient adsorption of Sb(III) ions [3]. The effects of contact time, pH and adsorbent dosage were examined. The residual Cu(II) concentration in filtrates after adsorption was analysed by atomic absorption spectrometry. The highest obtained adsorption capacity for Cu(II) ions was 12.66 mg g-1 at unadjusted pH after 10 minutes with 16 g L-1 adsorbent dosage. The selected sample after adsorption was characterized by X-ray diffraction and scanning electron microscopy. Adsorbed copper is most probably present in the form of a nanocrystalline compound which is yet-to-be-identified. 
The presented results propose Thymus serpyllum L. plant as a new potential biosorbent for Cu(II) ions, as well as a precursor to produce a nanocrystalline compound.

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