Nanocomposites and nanomaterials

Nickel-containing carbon composites for microwave-enhanced phenol degradation 
Galaburda M.V.1, Bogatyrov V.M.1, Sternik D.2, Oranska O.I.1, Derylo-Marczewska A.2 
1 Chuiko Institute of Surface Chemistry, National Academy of Sciences of Ukraine, 17 General Naumov Str., Kyiv 03164, Ukraine. 
mariia.galaburda@gmail.com
2 Faculty of Chemistry, Maria Curie-Skłodowska University, pl. Maria Curie- Skłodowskiej 3, 2 031 Lublin, Poland.

The purpose of this work was to explore the adsorption properties of nickel-containing composites toward phenol (Ph) with further application of microwave treatment for the pollutant degradation with simultaneous sorbent regeneration.
The composites with different content of the nickel were obtained by two-step method: (i) mechanochemical mixing of phenol-formaldehyde resin and appropriative amount of Ni(II) acetate tetrahydrate in a ball mill with porcelain drum; (ii) carbonization of the blends at 760 °C in argon atmosphere (flow rate 100 mL/min with heating rate of 5 °C/min). The pyrolysis of the mixture lead to the formation of crystalline metallic nickel and graphite-like structures. The metal content in the composites was 27.3, 46.1, and 65 wt.%, while carbon – 72.2, 53.9 and 35 wt.% with SBET of 279, 209, and 152 m2/g for Ni/C-1, Ni/C-2, and Ni/C-3, respectively. It was found that the adsorption capacity of the composites toward Ph was 3, 3.2, and 2.1 mg/g for Ni/C-1, Ni/C-2, and Ni/C-3, respectively (after 5h at 25 ± 2 °C) and depended on the porosity and carbon content. All sorbents were treated by MW irradiation (MW oven “Saturn”, 2.45 GHz - S band, 700 W,) for Ph decomposition. The operating time of radiation was 30, 60, 90, and 120 sec for all samples (Fig. 1). It is worth noting that the MW irradiation increased the adsorption capacity of Ni/C composites on the second cycle of the Ph adsorption.
In the present study, magnetosensitive Ni/C composites were synthesized by a simple two-stage solvent-free method with subsequent use as an efficient adsorbent for Ph removal from aqueous media. It was confirmed that Ni/C can be reused after several adsorption/MW regeneration cycles and its adsorption capacity maintained at a relatively high level.
Acknowledgement: This work was supported by the International Visegrad Fund (Contract number 51910536).