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Mushroom cultivation and consumption have been steadily increasing in recent decades, however, after mushroom cultivation, a large amount of by-products, known as spent mushroom substrate (SMS), are left behind in open dumps where about 5 kg of SMS are generated for every kilogram of mushroom (Agaricus bisporus). Around 51 million tons of SMS are produced in the world every year. Hydrothermal carbonization (HTC) is a promising technology for the conversion of SMS into a rich carbon product, hydrochar. The hydrochar was synthesized in a hydrothermal reactor at a temperature of 180 °C for a reaction time of 1 h. The characterization of the SMS and its chars was done by FTIR, SEM, and TGA analysis. The FTIR analysis showed that aromatic and oxygen-rich functional groups are dominant on the hydrochar surface. It was noticed that the hydrochar had more visible pores compared to the SMS. The porous structure and oxygen functional groups of hydrochar probably influenced the improvement of adsorption performance, since the adsorption capacity of SMS for Cd2+ ions was 28 mg L-1, while for hydrochar it was 92 mg L-1. On the other hand, the thermal kinetic analysis has shown that hydrothermally treatment upgrades the combustion behavior of hydrochar. The kinetic parameters were determined by Kissinger and Ozawa methods. The hydrochar had notably lower activation energy compared to the SMS, which means that this hydrochar requires a smaller amount of energy to start combustion. The preliminary results show that HTC effectively transforms SMS into alternative solid biofuel and eco-friendly sorbent.

The present work represents hydrogel as a composite based on sodium alginate and mesoporous SBA-15. The hydrogel was obtained by modifying mesoporous SBA-15 by a microencapsulation method of the SBA-15 in the sodium alginate matrix. The solution of CaCl2 provided a gelation complex of sodium alginate/SBA-15 in a rigid gel-like structure. The sodium alginate/SBA-15 hydrogels beads of about 3 mm diameter were prepared. Composite material was characterized by using powder X- ray diffraction, scanning electron microscopy and energy dispersive X-ray analysis. This composite material may have potential application in removal of metal ions – pollutants from aqueous solutions.

In this study, the adsorption capacity of Pb2+ removal from aqueous solution was examined by hydrochar of the spent mushroom substrate. In order to improve the adsorption capacity, hydrochar was previously activated with 2M KOH. The obtained results demonstrated that alkally activation increased the sorption capacity from 36 mg g-1 to 74 mg g-1. Structural characterization of activated and inactivated hydrochars were performed by FTIR analysis. Toward to obtained results of FTIR analysis, the increased of the oxygen functional groups (OFG) in activated hydrochars was perceived, which is contributed to the increase in the adsorption capacity of this carbonized material. Results indicated that spent mushroom substrate can be converted into hydrochar as a perspective sorbent for removal of Pb2+.

In this study, the adsorption capacity of Pb2+ removal from aqueous solution was examined by hydrochar of the spent mushroom substrate. In order to improve the adsorption capacity, hydrochar was previously activated with 2M KOH. The obtained results demonstrated that alkally activation increased the sorption capacity from 36 mg g-1 to 74 mg g-1. Structural characterization of activated and inactivated hydrochars were performed by FTIR analysis. Toward to obtained results of FTIR analysis, the increased of the oxygen functional groups (OFG) in activated hydrochars was perceived, which is contributed to the increase in the adsorption capacity of this carbonized material. Results indicated that spent mushroom substrate can be converted into hydrochar as a perspective sorbent for removal of Pb2+.

The present work represents hydrogel as a composite based on sodium alginate and mesoporous SBA-15. The hydrogel was obtained by modifying mesoporous SBA-15 by a microencapsulation method of the SBA-15 in the sodium alginate matrix. The solution of CaCl2 provided a gelation complex of sodium alginate/SBA-15 in a rigid gel-like structure. The sodium alginate/SBA-15 hydrogels beads of about 3 mm diameter were prepared. Composite material was characterized by using powder X-ray diffraction, scanning electron microscopy and energy dispersive X-ray analysis. This composite material may have potential application in removal of metal ions – pollutants from aqueous solutions.

Fig (Ficus carica L.) is a fruit of the Moraceae family, which is mostly grown in subtropical regions, but also grows in Serbia. Fig trees are usually grown in warm and dry climates. According to the FAO world production of figs is stable, with a decade-long average of about 1.1 million tons a year. Fig pomace are formed after fermentation of this fruit which is used for the preparation of brandy. The brandy industry generates huge amounts of pomace as industrial waste, so pyrolysis as thermochemical technologies was used for organic agro-industrial waste treatment. Biochar produced by pyrolysis of fig pomace at 500 °C were characterized and investigated as adsorbents for the removal of Pb2+ ions from aqueous solution. Fig pomace before and after pyrolysis was characterized using proximate, inorganic and elemental analysis, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and differential thermal analysis (DTA). Biochar has a carbon matrix with a high degree of porosity and large surface area, suggesting that it can be used as a surface adsorbent and thus have a significant role in controlling environmental contaminants. The surface modification by gamma irradiation was done to enhance the adsorption capacity of biochar. The Pb2+ ions contents in aqueous solution were analyzed using ICP-OES. The adsorption capacity was estimated using the Freundlich and Langmuir model. The results of this work suggest that pyrolysis and irradiation of biomass is a promising way to produce efficient heavy metal sorbents for waste-water treatment.

The use of waste biomass for the production of fuels, sorbent of different pollutants or natural fillers has significant economic and environmental benefits. Plum (Prunus domestica) is a lush fruit consisting of bones, flesh and skin. It can be consumed fresh, dried or used to make juices, jams and brandies known as plum brandy. Plum is also known as a laxative. During processing, plum pomace is formed as a by-product of plum brandy production. Plum pomace contains a large proportion of polyphenols, so it can be used to produce dietary supplements. Therefore, in this study, the gamma irradiation activated biochar of plum pomace was examined as a lowcost biosorbent of Cd2+ ions from aqueous solution. It was prepared using pyrolysis process at 500 °C for a reaction time of 1 h, then was activated by gamma irradiation. The characterization of plum pomace before and after pyrolysis was done by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and differential thermal analysis (DTA). Analysis of morphology and functional groups presented the formation of cracks on the biochar surface, which are mainly dominated by oxygen-rich functional groups. The adsorption capacity of activated biochar was higher than inactivated biochar because its improved surface functional properties after gamma activation. The Cd2+ ions contents in aqueous solution were analyzed using ICP-OES. The adsorption capacity was estimated using the Langmuir and Freundlich model. The findings of this study confirm that pyrolysis is a promising way to produce efficient environmentally friendly sorbents for wastewater treatment.

Biochar produced by pyrolysis of plum and fig pomace at 500 C were characterized and investigated as adsorbents for the removal of heavy metal ions from aqueous solution. Plum and fig pomace are formed after fermentation of this fruit which is used for the preparation of brandy. The brandy industry generates huge amounts of pomace as industrial waste, so pyrolysis as thermochemical technologies was used for organic agro-industrial waste treatment. Plum and fig pomace before and after pyrolysis was characterized using proximate, inorganic and elemental analysis, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and differential thermal analysis (DTA). Biochar has a carbon matrix with a high degree of porosity and large surface area, suggesting that it can be used as a surface adsorbent and thus have a significant role in controlling environmental contaminants. The surface modification by gamma irradiation was done to enhance the adsorption capacity of biochar. The heavy metals contents in aqueous solution were analyzed using ICP-OES. The adsorption capacity was estimated using the Langmuir and Freundlich model. The results of this work suggest that pyrolysis and irradiation of biomass is a promising way to produce efficient heavy metal sorbents for waste-water treatment.

A carbon-rich product, hydrochar, was synthesized by hydrothermal carbonization (HTC) of spent mushroom substrate (SMS), at temperature of 260 °C. The thermal kinetic analysis has shown that hydrothermally treatment improve the combustion behavior of hydrochar. The kinetic parameters were determined by Kissinger and Ozawa methods. The SMS-260 had a significantly lower activation energy compared to the SMS, which means that this hydrochar needs a smaller amount of energy to start combustion. Generally, the preliminary results show that HTC is an effective way to transform SMS into alternative solid biofuel.

Mesoporous silica renders chemical and mechanical stability under biological conditions, but due to its physicochemical properties, could be potentially harmful to exposed cells. The aim of the current study was to estimate SBA-15 (concentration of 50, 100 and 250 µg/mL) impact on human peripheral blood mononuclear cells to induce cyto- and genotoxicity in vitro after 72 h treatment, as well as lipid peroxidation in serum samples ex vivo. SBA-15 mesoporous silica treatment impact on cell viability was performed by XTT assay, lipid peroxidation was estimated by determining malondialdehyde and 4-hydroxyalkenals levels and genotoxicity by micronucleus assay. SBA-15 treatments displayed genotoxic potential at the lowest concentration, while highest tested concentration led to decrease of cell viability and increase of lipid peroxidation. Chemical modification of SBA-15 material that could influence its physicochemical properties could be useful way to lower its toxicity.

A new heterocyclic azo dye 5-(2,6-dimethylphenyl)-6-hydroxy-4-methyl-2-oxo-1,2- dihydropyridine-3-carboxamide was synthesized and structurally characterized by elemental analysis, FTIR, 1H and 13C NMR spectroscopy techniques. These analysis have confirmed that synthesized dye exists in the tinctorial strongest tautomeric form, hydrazone form. The dye is characterized by reflection spectrum, while absorption and emisson spectra are recorded in nine different solvents. The antioxidant activity of the synthesized dye has been chemically tested and has been shown to have great potential as an antioxidant molecule.

Removal of heavy metals is important because of their toxic effects on living organisms and unwanted anthropogenic effects. Biochar is suitable as an adsorbent of heavy metals due to its advantages such as various sources of biomass, a large number of microporous channels and surface functional groups, as well as due to its economic viability. There is no data about the plum pomace biochar usage as adsorbent for lead removal. In this study, the plum pomace biochar modified with gamma irradiation (IrPP) is used for the removal of Pb2+ ions from the aqueous solution. The SEM micrographs revealed that surface morphology of plum pomace is suitable for metal adsorption. The results of adsorption kinetics demonstrated that the removal process of Pb2+ ions onto IrPP follows a pseudo-second kinetic model, which is confirmed by a better agreement between qe,cal=227 mg g–1 and qe,exp=224 mg g–1. Therefore, based on preliminary research, it can be concluded that IrPP originating from biowaste is a promising, eco-friendly sorbent of heavy metal from wastewater.

Thermal degradation properties of the newly synthesized azo dyes derived from 6-hydroxy4-methyl-2-okso-1,2-dihydropyridine-3-carboxamidewere examined Depending on the nature of substituent that is located on the para position of the diazo components of azo pyridone dyes, different thermal stability can be obtained The thermal behaviour of the present dyes has been determined using thermogravimetric analysis (TGA), derivative thermogravimetry (DTG) and differential thermal analysis (DTA) On the basis of this method, non-isothermal kinetics was monitored To explain kinetics behavior of the investigated dyes during their degradation in an inert atmosphere, ASTM E698, ASTM E2890, Friedman’s (FR), OzawaFlynn-Wall (OFW) as well as Kissinger-Akahira-Sunose (KAS) isoconversional (modelfree) methods were applied. Numerical optimization was used in order to judge fitting capabilities including simulated and experimental curves, for estimated kinetic parameters It was found that different thermal stabilities of various dyes are the consequence of their different chemical structures, including diverse substituents. It was shown that significant difference in reactivity for hydroxy substituted and unsubstituted dyes is a consequence of reactivity dissimilarities between •OH and H• species.It was assumed that reactions with •OH are characterized with changing in limiting stage, from kinetic to diffusion controlled The numerical optimization shows a good fitting correlation between experimental and simulated process data Based on multi-level conversion analysis, using differential (FR) and integral (OFW and KAS) model-free methods, the all dyes, exhibit the different E-conversion dependency

Thermal degradation properties of 5-(4-substitutedphenylazo)-3-amido-6-hydroxy-4-methy1-2-pyridones and 5-(4-substitutedphenylazo)-3-cyano-6-hydroxy-4-methy1-2-pyridones dyes, differing in electron withdrawing and electron donating substitttents in para-position of diazo components were examined. The structure of the synthesized compourtds has been confirmed by H-1 NMR,C-13 NMR, FITR, UV-Vis and XRD analysis techniques. The results obtained with thermogravimetric analysis (TGA) - derivative thermogravimetry (DTG) and differential thermal analysis (DTA) were combined with GC-mass spectral fragmentation to obtain thermal decomposition mechanism. Non-isothermal kinetics were monitored by application of TGA-DTG-DTA. For Kinetic behavior of the investigated dyes during their degradation in an inert atmosphere, Kissinger, Ozawa, Flynn-Wall-Ozawa (FWO) and Kissinger-Alcahira-Sunose (KAS) isoconversional (model-free) methods were applied. It was found that different thermal stabilities of investigated dyes are the consequence of their different chemical structures, including diverse substituents.

This paper investigates the ability of waste apricot (Prunus armeniaca) kernel shells (AKS) bio-char prepared by single-step carbonization process at 850 °C (residence time of 1 h) for possible removal of toxic elements and organic micro-pollutants. The experiment that was performed as well as parameters used proved to be optimal for bio-char production as adsorbing medium, where last issue is validated by multiform material characterization techniques. It has been shown that the produced bio-char possess highly-porous morphology features, with large specific surface area (328.570 m2 g−1). The obtained product was characterized by various pore sizes (including super-micropores and mesopores with maximum pore size of 2.24 nm) structures. Preliminary results are indicated that obtained bio-char can shows increased affinity to possible adsorption of the small organic molecule contaminants upgraded by its physico-chemical properties. Cost estimation of AKS bio-char production substantiated its cost effectiveness and its good physical and chemical properties for future design in batch adsorption and regeneration tests. It was established that AKS produced bio-char was 2.5 times cheaper than the commercially available activated carbon. Bio-char exhibits promising removal performances for potential adsorption of heavy metal and organic micro-pollutants from wastewaters systems, as indicated by material textures and spectroscopy measurements. © 2019 Elsevier Ltd

Polychlorinated biphenyls (PCBs) are the most highly toxic species of POPs. More than 200 PCB congeners exist in nature. [1] PCBs are highly toxic for humans. They enter the human body via inhalation, ingestion or sorption through the skin and the bloodstream transports them to the organs, muscles and adipose tissues, where they are accumulated. This study presents the validation of analytical method for determination of 7 PCBs congeners in soil: PCB 28, PCB 52, PCB 101, PCB 118, PCB 153, and PCB 180. The method is based on solid- liquid extraction with cyclohexane and the analysis by gas chromatography with mass spectrometric detection (GC-MS). [2] Samples were analyzed in SIM mode, and the analytes qualitative confirmation was performed comparing the mass spectra of analytical standards of PCB congeners with the NIST data base. The method developed can be applied in range from 0,005 to 10 mg/kg with the appropriate parameters of precision, accuracy, repeatability and linearity and can be used for simultaneous determination of low PCBs concentrations in different types of soil (agricultural, contaminated soil, etc.).

Introducing standards into management processes in enterprises, laboratories, control bodies, etc. have the great importance both for the improvement of business and for its basic survival. Over time, standards have become an integral part of each system. At the same time, through the feedback, standards have been changing in order to improve management system and to fulfill of the common interests of the system and the user. One of the main improvements of management is the integration of the standards ISO 9001, ISO 14001 and ISO 45001. The aim of this paper is to present the benefits of implementing an integrated quality, environmental, occupational health and safety management system in order to improve the realization of scientific research projects and in processes of applied research in the Scientific Department of Institute of Nuclear Science ‘Vinca‘. Through integration of standards ISO 9001, ISO14001 and ISO 45001 the Scientific Department has established, documented, applied and maintained an integrated quality management system, which elements will be further discussed. In order to achieve a sustainable development of scientific, educational, technical and market-oriented business system, the Scientific Department continuously improves effectiveness of integrated quality management system.