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-Introduction. Apricots (Prunus armeniaca L.) have an important role in Serbia's fruit production. Average annual production of 25,035 t generates approximately 1,577 t apricot stone (AS) waste and most of it ends up in landfill sites. In order to minimize the environmental impact, an investigation of the possible use of AS was done by developing a biosorbent for wastewater treatment. Materials and methods. AS waste from the fruit processing industry was used to remove Cu(II) ions from water solution by batch adsorption techniques. This solid waste residue was characterized by FTIR, SEM and EDX. The effects of pH, contact time, metal concentration and biosorbent dosage on the process of biosorption were studied. Results and discussion. Obtained FTIR results confirm that the uptake of Cu(II) ions from aqueous solution involves carboxylate moieties from lignin and fatty acids. Also, the presence of seeds in the AS blend significantly increased biosorption performance providing active sites important for the sorption process. The ion exchange mechanism was also confirmed. The best fitting adsorption model is the Langmuir model and the maximum biosorption capacity (q max ) is 4.45 mg L −1 at pH 5.0. Biosorption of the Cu(II) ions follows a pseudo secondorder kinetic model. According to thermodynamic parameters the biosorption process is endothermic and spontaneous. Conclusion. Numerous biosorbents were investigated for biosorption of Cu(II) ions from aqueous solution, but no report on application of untreated AS waste has been found in literature. This preliminary study confirmed that this material can successfully and rapidly remove dissolved copper ions from dilute solutions.Keywords: Serbia / apricot / Prunus armeniaca / waste management / biosorption / copper ions Résumé -Application des déchets de noyaux d'abricot issus de l'industrie agro-alimentaire à la dépollution : étude de la biosorption du cuivre. Introduction. L'abricot (Prunus armeniaca L.) tient une place importante dans l'économie de la Serbie. La production annuelle moyenne de 25 035 t génère environ 1 577 t de déchets de noyaux d'abricots (AS) dont la plus grande partie se retrouve dans des sites d'enfouissement. Afin de minimiser l'impact environnemental de ces déchets, une l'utilisation possible des AS a été envisagée, visant à développer un biosorbant pour le traitement des eaux usées. Matériel et méthodes. Les déchets AS provenant de l'industrie agro-alimentaire ont été utilisés pour éliminer les ions Cu (II) de solutions aqueuses par des techniques d'adsorption par lots. Le résidu des déchets solides a été caractérisé par spectroscopie infrarouge à transformation de Fourier (FTIR), microscopie électro-nique (SEM) et radioscopie à dispersion d'énergie (EDX). Les effets du pH, du temps de contact, de la concentration et du dosage du métal sur le biosorbant ont été étudiés au cours du processus de biosorption. Résultats et discussion. Les résultats obtenus par FTIR confirment que l'absorption des ions Cu (II) de la solution aqueuse met e...

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Nanosize NiFe2O4 was prepared by template method and precipitation process using same starting materials. The use of soluble starch in both synthesis routes was investigated. The amount of the used precipitating agent (Na2CO3) for the precipitation approach was selected according to two adopted scenarios based on theoretical and average yield of possible side reaction expressed by the degree of substitution (DS). The results of SEM microstructural analysis of the prepared Niferrite powders demonstrate evident influence of the applied preparation method whereas high-magnification FE-SEM images show very similar fine-grained structures characterized by different size of particles. According to the results of XRD analysis, the obtained ferrite powders exhibit only slight differences in phase composition with calculated crystallite size for template sample dXRD = 36 nm and for the both precipitation route samples dXRD = 21 nm. Additional sample characterization using 57Fe M?ssbauer spectroscopy supports the findings of the microstructural and XRD analysis. The ?clearest? spectrum was obtained for the template sample while the strongest influence of nanocrystalline component was observed for the sample prepared with maximal amount of precipitation agent (DS=3). The room temperature magnetic hysteresis loops, recorded using vibrating sample magnetometer (VSM), are very similar and exhibit characteristic shape with values of magnetic properties within expected range for this type of material. [Projekat Ministarstva nauke Republike Srbije, br. OI 172037 i br. TR34023]