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In this paper, the character of structural changes induced by different mechanical treatments to Prunus persica stones (PSs), and its subsequent effect on biosorption kinetics of Cu(II) were investigated. PSs were processed in vibratory disk mill (PS-V) and ultra-centrifugal mill (PS-C) and characterized by XRD, BET, SEM and FTIR spectroscopy. It was shown that PS-V was smaller and more reactive with less crystallinity index and hydrogen bond intensity compared to PS-C. In opposite, surface area of the PS-C was bigger than that of the PS-V. The total pore volume was about threefold, while the volume of micro pores was 9.29 times higher in PS-Cs than in PS-Vs. The kinetics of Cu(II) biosorption by both PSs was tested through various kinetic models: pseudo-first and pseudo-second order rate equations, Elovich equation, Boyd model, Weber-Morris and Urano-Tachikawa intraparticle diffusion model. For both sample types, Cu(II) biosorption occurred through combination of intraparticle and film diffusion mechanism, while kinetic results were best described by the pseudo-second order kinetic model. At the same time, the results indicated that together with kinetic rate the biosorption capacity of PS-C (21.20 mg g(-1)) was higher than that of PS-V (16.30 mg g(-1)). Mechanical activation like crushing and grinding will change material particle size, specific surface area and porosity, as well as its crystallinity. However, this paper elucidates that such physical structural changes will impact on heavy metal ions removal efficiency. This investigation suggests that the type of size reduction in lignocellulosic biosorbent preparation plays a very important role in overall biosorption performance, so it should be carefully considered every time when the mechanical treatment of material is necessary to be applied.

Aflatoxin B1 (AFB1), ochratoxin A (OTA), zearalenone (ZON), deoxynivalenol (DON) and T-2 toxin are the most extensively studied toxic fungal metabolites. Once mycotoxins enter the food/feed production chain keeping their toxic characteristics, it is very difficult to remove or eliminate them. One of promising methods to reduce mycotoxins in contaminated food/feedstuffs is the use of mycotoxin binders. This paper presents the results of in vitro investigations of mineral mycotoxin binders (bentonite - BEN, diatomite - DIA and zeolite - ZEO), and organic mycotoxin binders - agricultural waste materials (Myriophillium spicatum, peach and sour cherry pits). Chemical compositions of the adsorbents have showed that they do not consist of elements toxic to the animals. Inorganic adsorbents (BEN, DIA and ZEO) tested in vitro were better binders of AFB1 (94.97% - 96.90%), while the biosorbents were more efficient in adsorption of OTA (19.98% - 66.66%), ZON (33.33% - 75.00%) and T-2 toxin (16.67% - 50.00%). Inorganic adsorbents and organic waste materials expressed similar binding capacity for DON in vitro, with the exception of M. spicatum that did not at all adsorb this type B trichothecene. Our results indicate that feed contamination with different types of mycotoxins might be diminished by a product that combines different inorganic and organic adsorbents with diverse mycotoxin binding properties., Aflatoksin B1 (AFB1), ohratoksin A (OTA), zearalenon (ZON), dezoksinivalenol (DON) i T-2 toksin su najviše izučavani toksični metaboliti gljiva. Kada mikotoksini uđu u proizvodni lanac za hranu/hranu za životinje, zadržavajući svoje toksične karakteristike, teško ih je ukloniti ili eliminisati. Jedna od obećavajućih metoda za smanjenje nivoa mikotoksina u kontaminiranoj hrani/hrani za životinje je korišćenje mikotoksinskih veziva. Ovaj rad predstavlja rezultate in vitro istraživanja mineralnih mikotoksinskih veziva (bentonit - BEN, diatomit - DIA i zeolit - ZEO) i organskih veziva mikotoksina - poljoprivrednog otpadnog materijala (Myriophillium spicatum, koštice breskve i višnje). Hemijski sastavi adsorbenata pokazali su da ne sadrže elemente toksične za životinje. Neorganski adsorbenti (BEN, DIA i ZEO) testirani in vitro bolje su vezivali AFB1 (94,97% - 96,90%), dok su biosorbenti bili efikasniji u adsorpciji OTA (19,98% - 66,66%), ZON-a (33,33% - 75,00% ) i T-2 toksina (16,67% - 50,00%). Neorganski adsorbenti i organski otpadni materijali su pokazali sličan kapacitet in vitro vezivanja DON-a, sa izuzetkom M. spicatum koji uopšte nije adsorbovao ovaj trihotecen tipa B. Naši rezultati koji su prikazani ovde pokazuju da zagađivanje hrane i hrane za životinje različitim vrstama mikotoksina može biti smanjeno dodavanjem preparata dobijenog kombinacijom različitih neorganskih i organskih adsorbenata koji poseduju različite karakteristike vezivanja mikotoksina.

The most important source of renewable energy in Serbia represents biomass (60.3 %) with total potential of 3.405 million toe. Almost half of this amount (1.67 million toe) represents agricultural and industrial waste, with further negligible revalorization. Various investigations have demonstrated that agricultural byproducts have promising capacities to remove a variety of pollutants, which might increase the sustainability of their life cycle. This paper investigates the possible use of lignocellulosic waste material (LCW), originating from food industry as biosorbent for heavy metals, and later as a solid fuel. For this purpose we have used peach stone particles (PS) obtained by mechanical activation of this LCW as Cu(II) sorbent. The physical and chemical characteristics of PS reveal its complex structure which was confirmed by SEM, and FTIR analysis. PS behavior on pyrolysis process was studied by dynamic thermo gravimetric and derivate thermo gravimetric analysis. Results show that this lignocellulosic waste can be applied as sorbent and as a fuel. This approve that this agricultural waste can be a resource more than a waste and that it does not need to be disposed of in the costly and inefficient way, which is especially important in developing economies, like Serbian.

This paper presents an eco-friendly approach for minimizing heavy metal pollution, offering food waste valorization and energy source at the same time. It focuses on Cu(II) sorption by low cost sorbent developed by mechanical treatment of Prunus persica L. stones, a food industry waste biomass. Removal of Cu(II) was studied at different operating parameters in a batch sorption system, with special attention on temperature effect on sorption process. The pseudo-first order, pseudo-second order and Elovich model were applied to test kinetic experimental data. Equilibrium experimental results were fitted to Langmuir, Freundlich, Sips, Toth and Dubinin-Radushkevich isotherms to elucidate the type and sorption performance. Characteristic functional groups responsible for Cu(II) binding and thermal behavior of PS have been investigated using FT-IR and TGA analyses. The activation parameters were calculated using Arrhenius and Eyring equations. Using equilibrium data at different temperatures, thermodynamic parameters Delta G degrees, Delta H degrees and Delta S degrees were calculated, suggesting that the sorption of Cu(II) on PS is spontaneous and endothermic process with increased randomness during the sorption. The isosteric heat of adsorption (Delta H-iso) was determined, suggesting the non -uniformity of PS surface and lateral interactions among ions sorbed. Desorption experiments performed with different chemicals have confirmed the reusability of PS for five cycles, without losing and even improving its sorption capacity. Results presented in this paper might help in appropriate design of purification systems using this type of lignocellulosic waste.