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The probability of Cs+ and Co2+ ions retention by immobilization processes in the cement matrix was determinate as the subject of analyses: matrix design, water/cement ratio, and structure porosity. Comparison of experimental results was accomplished by Hespe standard leaching method. Diffusion and semi-empirical models were used for the assessment of the washing rate as a function of time. The higher value of cement matrix mechanical resistance corresponds to a lower value of Co2+ and Cs+ ions leaching. The Co2+ leaching level was more than two orders of magnitude less than the leaching level of Cs+. The influence of bentonite and zeolite on Co2+ leaching reduction was significantly smaller in comparison with Cs+, while zeolite had a higher Cs+ and Co2+ sorption ability than bentonite. Under static leaching conditions, the contribution of diffusion to the total transport of ions in the matrix porous medium was dominant. The contribution of matrix dissolution was insignificant concerning the dominant contribution of diffusion and surface washing. The semi-empirical model showed a better approximation of the Co2+ and Cs+ ions laboratory leaching process.

Opekarski i keramički materijali čine oko 54 % ukupne količine građevinskog otpada. Tokom poslednje decenije, interesovanje za upotrebu ovakvih otpadnih materijala i njihovih nusproizvoda kao sorbenata za prečišć avanje kontaminiranih voda i vodenih rastvora, znatno je poveć ano. Istraživanja su pokazala da bi upotreba otpadnih opeka u procesu sorpcije mogla da bude vrlo efikasna i ekonomski isplativa alternativa za imobilizaciju (solidifikaciju) tečnog radioaktivnog otpada. U ovom radu prikazani su rezultati matematičkog modelovanja izotermi Langmuir-ovim i Freundlich-ovim modelom. Langmuir-ov model znatno bolje opisuje eksperimentalne podatke dobijene za sorpciju Co(II) i Ni(II) jona na uzorcima pune opeke, dok je sorpcija oba jona na uzorku šuplje opeke bolje opisana Freundlich-ovim izotermama. Brick and ceramic materials represent about 54 % of the total amount of construction and demolition waste. Over the last decade, interest in the use of these waste materials and their by-products as sorbents for the treatment of contaminated water and water solutions has increased significantly. Research has shown that the use of waste bricks in the sorption process could also be a very efficient and economically viable alternative for immobilization (solidification) of liquid radioactive waste. In this paper, the results of mathematical modeling of isotherms by Langmuir and Freundlich models were presented. The Langmuir model productively describes the experimental data obtained for the sorption of Co (II) and Ni (II) ions onto solid brick samples, while the sorption of both ions onto the hollow brick sample was better described by the Freundlich isotherm. XXXI Симпозијум Друштва за заштиту од зрачења Србије и Црне Горе, 06-08. октобар 2021. Proceedings: [https://vinar.vin.bg.ac.rs/handle/123456789/9668]

Sastav otpadnih cementnih materijala (OCM), kao što su beton i fasadni materijal, baziran je na kvarcu i kalcitu. Zahvaljujući kalcitu i baznom karakteru, ovakvi matriksi pokazali su zadovoljavajući afinitet sorpcije Sr(II) i Co(II) jona. Ispitivanjem uticaja početne koncentracije jona u rastvoru na sorbovanu količinu omogućeno je definisanje sorpcionih izotermi. U ovom radu prikazani su rezultati matematičkog modelovanja izotermi Langmuir-ovim, Freundlich-ovim i linearnim modelom. Ustanovljeno je da Langmuir-ov model znatno bolje opisuje eksperimentalne podatke dobijene za sorpciju Co(II) jona na fasadnom materijalu, dok je sorpcija na uzorku otpadnog betona bolje opisana Freundlich-ovom izotermom. Sorpcija Sr(II) jona na OCM pokazala je praktično linearnu zavisnost. The composition of waste cementitious materials (OCM), such as concrete and facade material, is based on quartz and calcite. Due to calcite and base character, these matrices showed a satisfactory sorption affinity for Sr(II) and Co(II) ions. By examining the influence of the initial concentration of ions in the solution on the sorbed amount, it is possible to define sorption isotherms. In this paper, the results of mathematical modeling of isotherms by Langmuir, Freundlich, and linear models were presented. It was found that Langmuir’s model significantly better describes the experimental data obtained for the sorption of Co(II) ions on the facade material, while the sorption on the waste concrete sample is better described by the Freundlich isotherm. Sorption of Sr(II) ions on OCM showed practically linear dependence. XXXI Симпозијум Друштва за заштиту од зрачења Србије и Црне Горе, 06-08. октобар 2021. Proceedings: [https://vinar.vin.bg.ac.rs/handle/123456789/9668]

Ispitivanje uticaja početne koncentracije Sr(II) jona u vodenom rastvoru na sorbovanu količinu omogućava definisanje sorpcionih izotermi. U ovom radu prikazani su rezultati matematičkog modelovanja izotermi Langmuir-ovim i Freundlich-ovim modelom, kao i linearnim modelom. ANOVA testom utvrđeni su koeficijenti određenosti (R2) za Langmuir-ov i Freundlich-ov model. Izračunate vrednosti bile su manje od 0,9 što znači da se dati modeli ne slažu dobro sa eksperimentalnim podacima. Međutim, sorpcija Sr(II) jona na uzorcima otpadne opeke pokazala je skoro linearnu zavisnost, odnosno vrednosti koeficijenta određenosti većih od 0,9 na datom modelu. Investigation of the influence of the initial concentration of Sr(II) ions in an aqueous solution on the sorbed amount enables the definition of sorption isotherms. This paper presents the results of mathematical modeling of isotherms by the Langmuir and Freundlich models, as well as by the linear model. The coefficients of determination (R2) for the Langmuir and Freundlich models were determined by the ANOVA test. The calculated values were less than 0.9, which means that the given models do not agree well with the experimental data. However, the sorption of Sr(II) ions on waste brick samples showed an almost linear dependence, i.e. values of the coefficient of determination greater than 0.9 on a given model. XXXI Симпозијум Друштва за заштиту од зрачења Србије и Црне Горе, 06-08. октобар 2021. Proceedings: [https://vinar.vin.bg.ac.rs/handle/123456789/9668]

This paper represents an overview of the investigations of cementitious waste materials (CWM) utilization in Sr, Co, and Ni radionuclides immobilization by sorption. The highest Co2+ and Ni2+ ions removal efficiency was achieved using a wall-concrete sample, while the Sr2+ uptake was equal on all. The results agreed with the sorption capacity of investigated ions onto C-S-H (calcium silicate hydrate) as the main hardened cement-paste component. Studies showed that the use of CWM in the conditioning of liquid radioactive waste (LRW) could represent the efficient and economically viable alternatives for commonly used methods.

This paper presents an integrated environmental management plan for soil quality control in the city of Novi Sad in the Republic of Serbia. Considering the very favorable geographical position, Novi Sad is a city that interweaves important main roads, has population increase, as well as the rapid development of industry and agriculture. Due to these facts there is also increased pollution of air, water and soil, as well as generation of large waste amount. In addition to parks and devastated areas around the industrial zones, widespread agricultural activity in suburban areas is particularly sensitive to the soil quality and vice versa. In this study, the geographical position and geomorphological characteristics of the city area, as well as the leading ecological problems, were analyzed. Based on the given facts, an integrated monitoring of one of the environmental quality indicators, the soil quality was proposed. There was suggest the network of 15 sensors for measuring of pH value, humidity and soil temperature in the city area. Soil quality data obtained in this way in real time is very important for elimination or mitigation of potential undesirable consequences. Thanks to the rapid development of technology, the utilization of sensors network is increasingly being used in modern monitoring systems and is available for efficient and cost-effective solution of environmental problems.

The modern way of life and aspiration for faster technological development creates increasing problems related to waste quantities and management. Waste management is a complex process due to the constant danger to the environment through pollution of air, water and soil as well as the human health. Lack of waste quantity, composition and location informations makes disposal and categorization process more difficult, as well as its recycling or reuse. Industrialization and development of modern society and irrational usage of natural resources increases the amount of waste, which creates the need for an organized approach to this problem. In order to resolve these issues, among other, the constant monitoring, implementation of legislation and increasing public awareness are necessary. This particularly refers to the collection of reliable data on the quantities of generated waste, and its disposal within the local communities and protected areas. There is no systemic organized waste management in the Republic of Serbia for the time being. However, there is the long-term strategy in the field of environmental protection, which implies improving the population quality of life and preserving the nature, where an important place has the proper waste treatment.

UTILIZATION of WASTE MATERIALS in HEAVY METALS and RADIONUCLIDES IMOBILIZATION by SORPTION the researching trend of sorption characteristics of various natural materials, i.e. easily accessible raw materials, by-products or waste from various types of industry in recent years has become more pronounced. Waste materials utilization reduces the exploitation of natural non-renewable resources and/or exploitation of various forms of energy for synthesis or modification of natural raw materials and artificial materials. Also, the utilization of waste materials as sorbents is extremely acceptable from the aspect of environmental protection since it affects the amount reduction of such waste types, costs of their disposal and reduction of the hazards risks that some of these wastes can potentially cause in the environment. This paper presents an overview of the contemporary research of waste materials in heavy metals and radionuclides immobilization. Studies have shown that the usage of waste materials in the sorption process, i.e. conditioning of liquid radioactive waste and wastewater treatment can be very efficient and economically viable alternatives for standardly used methods, i.e. sorbents. Recent research on application of different waste materials and undemanding techniques for their modification due to sorption process improving include a wide range of waste materials, such as the various types of sludge, slag, fly ash, biomass, food waste, construction and demolition waste, etc.

Otpadni cementni materijali (beton i fasada) su bazirani na kvarcu i kalcitu. Prvenstveno zahvaljujući kalcitu i baznom karakteru, ove matrice su pokazale visok afinitet prema jonima nikla. Ispitivanje uticaja početne koncentracije jona Ni u rastvoru na sorbovanu količinu omogućava definisanje sorpcionih izotermi. U ovom radu su prikazani rezultati matematičkog modelovanja izotermi Langmuir-ovim i Freundlich-ovim modelom. Langmuir-ov model znatno bolje opisuje eksperimentalne podatke dobijene za sorpciju na betonu, dok je sorpcija otpadnom fasadom bolje opisana Freundlich-ovom izotermom. Waste cementous materials like concrete and facade are primary consisted of quartz and calcite minerals. As a consequence of calcite content as well as strong alkalinity, these matrices showed high sorption potential toward nickel ions. The investigation of initial Ni concentration effect onto sorbed amounts, enabled the sorption isotherm curves determination. In this paper are given results of mathematical modelling using Langmuir and Freundlich model. The better sorption data description was obtained using Langmuir model in the case of concrete sample, while, Freundlich model was more suitable for description of sorption onto facade. Proceedings: [http://vinar.vin.bg.ac.rs/handle/123456789/8681] XXX симпозијум ДЗЗСЦГ (Друштва за заштиту од зрачења Србије и Црне Горе), 2- 4. октобар 2019. године, Дивчибаре, Србија

Građevinski otpad, kao inertan čvrsti otpad, zauzima značajne kapacitete komunalnih deponija. U ovom radu ispitana je mogućnost valorizacije otpadnih keramičkih pločica i crepa, kao silikatnih matrica za uklanjanje jona Co2+, Sr2+ i Ni2+ iz trokomponentne smeše. U cilju utvrđivanja stabilnosti veza uspostavljenih između katjona i sorbenata, primenjena je metoda sekvencijalne ekstrakcije. Sorpcija jona Sr2+ je bila najmanje efikasna, usled kompeticije između jona u polaznoj smeši i značajne količine konkurentnih Ca2+ jona otpuštenih iz otpadnih materijala. Sorbovani joni Sr2+ su u visokom procentu ekstrahovani u okviru jonoizmenjivačke frakcije i frakcije rastvorne u slabim kiselinama, te su pokazali i najmanju stabilnost. Nasuprot tome, ispitani materijali su sorbavali Co2+ i Ni2+ jone u značajnoj količini, a njihova distribucija ukazuje na uspostavljanje jačih hemiskih veza. Uzimajući u obzir, količine, dostupnost i hemijsku kompatibilnost sa solidifikacionim matriksima koji se koriste za trajno odlaganje radioaktivnog otpada, rezultati ukazuju na potencijal primene građevinskog otpada umesto prirodnih mineralnih sorbenata. Construction and demolition waste is an inert solid waste which occupies significant capacities of the municipal landfills. The possibility of the valorization of waste ceramic and roof tiles, as silicate matrices for Co2+, Sr2+ and Ni2+ removal from three-component solution, was explored. In order to determine the stability of the bonds established between the cations and the sorbents, the method of sequential extraction was applied. Sr2+ sorption was the least efficient, due to the competition with other cations in the starting mixture and significant amounts of concurrent Ca2+ ions released from the waste materials. High percentages of sorbed Sr2+ ions were extracted in ion-exchangeable and acid soluble fractions, showing the lowest stability. On the other hand, Co2+ and Ni2+ sorption was more efficient and their distribution implies establishment of stronger chemical bonds. Taking into account the amounts, availability and chemical compatibility with matrixes for radioactive waste solidification and disposal, the obtained results demonstrate the potential applicability of construction and demolition waste as an alternative to natural mineral sorbents. Зборник радова : XXIX симпозијум ДЗЗСЦГ : Сребрно језеро, 27-29. септембар 2017. године

U ovom radu je upoređena efikasnost različitih biosorbenata u procesu uklanjanja jona Mn2+ iz vodenih rastvora. Efekat inicijalne koncentracije jona Mn2+ na sorbovanu količinu je ispitan primenom sledećih sprašenih materijala: kompost rečne korovske biljke (KB), žarenih goveđih kostiju (ŽK), ljuštura školjki (LJŠ) i pepela pirinčane pleve (PPP). Sorbovane količine Mn2+ su rasle sa porastom polazne koncentracije, a maksimalni kapaciteti biosorbenata određeni konstruisanjem sorpcionih izotermi, rasli su u nizu: PPP