Raw and pyrolyzed samples of the plane tree seeds (PTS) were tested by various advanced analytical techniques including simultaneous TG-DSC technique, FTIR analysis, X-ray diffraction (XRD) analysis, Raman spectroscopy analysis, GC-MS (gas chromatography-mass spectrometry) analysis and scanning electron microscope analysis, for its characterization procedure and the pre-treatments in possible application in CCS. Nondestructive analytical method (XRD) showed that raw material is typical for carbon-rich material, where was identified increase in interlayer spacing within graphite structure. The XRD results of pyrolyzed sample at 850°C showed a sudden loss in interlayer spacing. Spectroscopic analyses of pyrolyzed sample demonstrated the presence of typical aromatic structures found in amorphous carbon. Results indicate the high levels of the growth in basal planes of graphite structure in pyrolyzed sample. It was established that integrated reaction model parameters for pyrolysis of untreated PTS sample realistically describe active temperature period required for charcoal forming, under non-isothermal conditions. It was found that mechanical treatment of material results in increase in the number of chemical compounds. Micrograph showed the presence of variety of shapes and structures, where after pyrolysis, some dissipated pores were detected. One of these pores was partially blocked in some places, depending on the size of surface area. The results showed that the resulting char has very good features for further activation process, while the PTS would represent a good candidate in its application in the CCS.Journal of Thermal Analysis and Calorimetry (2018) 133:465-480 https://doi.org/10.1007/s10973-018-7207-x( 012 3456789(). ,-volV) (0123456789().,-volV)

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In presented paper, influence of temperature, precursor concentration and different hydroxides on properties of activated carbon obtained from saccharose were investigated. The samples were prepared by hydrothermal treatment and activated using KOH, NaOH and LiOH. Two saccharose concentrations (0.5, 1.0 mol/dm 3) and three temperatures (160, 200, 240 ºC) were changed in hydrothermal treatment. Activation processes were performed at 750 ºC under N 2 atmosphere. Samples were characterized by X-ray powder diffractometry, elemental analysis, N 2 adsorption-desorption measurements, Fourier-transform infrared spectrometry, scanning electron microscopy and thermal analysis. The obtained samples were tested for potential application in dyes removal from water solutions.

In the presented paper, activated carbons were prepared from fructose and glucose, and activating agents (KOH, NaOH, LiOH) by hydrothermal treatment (HTC) treatment. After preparation, samples were characterized in details. Different techniques were used: x-ray powder diffraction analysis, Raman spectral analysis, elemental analysis, and determination of textural and morphological properties. Obtained results showed dependence of investigated properties and the nature of precursors (glucose or fructose) as well as the type of hydroxides used as activating agents. After characterization, samples were tested as materials for heavy metals (Pb 2+ , Cd 2+ and Zn 2+) and methylene blue removal. Also, adsorption experiments were performed on wastewaters taken from tailings of the lead and zinc mine and kinetic of the methylene blue removal was studied. The factors which distinguished the KOH activated samples were high yield (~14%), content of organic carbon (63-74%), porosity and specific surface area (S BET~7 00-1360 m 2 /g), a low degree of the crystal phase, indications that potassium ions may be included in heavy metals removal, good removal of the heavy metal ions (~47-59 mg/g for Pb 2+ ,~21-27 mg/g for Cd 2+ and 6-10 mg/g for Zn 2+) and fast (~10-30 min) and good methylene blue (~60-200 mg/g) removal.

The present study reports the new facile methodology for synthesis of symmetrical and asymmetrical thioureas by an one-pot reaction of amine, carbon disulfide and oxidants: hydrogen peroxide, ethylenediamine tetraacetic acid (EDTA)/sodium percarbonate system or air. The structures of the synthesized compounds were confirmed by IR, 1H and 13C NMR and MS methods. Reaction mechanism has been proposed on the basis of reaction intermediate isolation and their structure determination. The synthetic benefits of the presented methods is reflected in the operational simplicity, mild reaction conditions, short reaction times, recycling of solvent, high purity and yield of products, absence of dangerous by-products and technological applicability at industrial scale. Considering commercial importance of the thioureas, it can be emphasized that implementation of the optimal synthesis of thiourea, based on presented methods, at industrial level of production would provide concurrent alternative to existing technologies in use. [Projekat Ministarstva nauke Republike Srbije, br. 172013]

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