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Background: Reuse of waste materials present in the technosphere, such as the metal mining tailings is becoming a more economical and energy-efficient method for obtaining the raw materials than the classical mining. Number of patents are presenting methods for tailings recycling, often in construction industry and metallurgy. At the same time, world market for metallic nanomaterials is rapidly increasing with numerous new applications and these two subjects should be connected. Methods: Paper presents the hypothesis that fine sludge from the metal mining tailings could be dominant source of the raw material for the nanotechnology. The idea is based on the fact that most of the usual publications present methodologies for synthesis of nanomaterials only from high-quality chemicals which is often expensive and unsustainable. Proposition here says, that it would be more economical to use the tailings as one of the technospheric wastes, directly by extracting the metal ions, selectively precipitating their cations and subsequently using them in nanotechnologies. Arguments are given by cross-comparison of the literature and patents on iron, bauxite, lead/zinc, copper, tailings and also the extraction of rare earth elements from tailing resources. Results: Metal mining tailings are shown to be an emerging subject in various research papers and patents together with other secondary raw materials. Conclusions: Use of the metal mining tailings as the resources in nanotechnology, is a large energysaving potential. Taking advantage of this readily available technospheric waste which contains mostly micrometer particles, should contribute also to the zero-metal waste goals.

Historical disposal sites of red mud can be found all around Europe, most notably at Sardinia, in Hungary, or at many locations in East-Southeast Europe. Red mud contains dominantly iron, aluminum, and silicon oxides, with races of various metals and compounds that can still be reprocessed if appropriate methods are applied. Some of the promising methods include microorganisms, and in particular bacteria.The main objective of the study was to determine whether prolonged bacterial activity changes the geochemistry of the red mud. The bacteria for the experiment were isolated through several selective steps from activated sludge of wastewater treatment plant and red mud from three different locations: Dobro Selo and Zvornik (Bosnia and Herzegovina), and Almásfüzitő (Hungary).After successful isolation, the bacteria were applied to the homogenized red mud samples, with nutrient media and water added in different combinations and ratios. The experiment lasted for 6 months after the bacteria were first applied to the red mud samples. During this period, geochemical analyses of the red mud were carried out twice, after 4 weeks and after 24 weeks, while the analysis of bacterial survival and quantity in the red mud samples were carried after 4, 8, and 24 weeks. The goal of geochemical analyses was to determine whether the bacteria caused changes in the concentrations of the elements of interest in the red mud when used as cultivating substrate and whether the elements of interest became more available to the bacteria due to their growth and adaptation to the red mud.Prior to geochemical analysis, subsamples were heated at 100°C for 60 minutes to induce bacteriolysis and filtered twice with MiliQ water (red band filter paper). The eluates were stored in plastic cuvettes and kept in a dark place at 4°C until analysis (HR-ICP-MS). The filter papers containing the treated red mud were dried, sealed, and stored for further geochemical analysis of total major and trace element concentrations by ICP-MS and mineralogical (XRPD) analyses. Detailed results of the geochemical and mineralogical analyses are pending.This work has been supported by EIT Raw Materials project RIS-RESTORE, project number 19269.

Intensity of electromagnetic pollution is followed by rapid increasing of new telecommunication technologies over the years. In order to prevent enlarged exposed of general population with doses of electromagnetic radiation above allowed for general population, living as well as working environment around antenna systems should be tested. Using sophisticated measurement equipment we measure intensity of electric field emitted from base station located at shopping center in urban zone of the Banja Luka city. Theoretical estimation of exposition was preceded to measurement procedure, resulting in mapping of exposure at different altitude around antenna system. This thorough investigation of electromagnetic pollution will become a part of typical systematic testing of high frequency non-ionizing radiation pollution. Tested area, around shopping center, where are located educational institution and sports center is found safe from emitted radiation.

The management of air quality at landfills has, among other things, the objective of controlling of waste management efficiency at the landfill. Modern landfills, although built in accordance with domestic and European regulations, affect the quality of the air in the areawherethey are located. The challenges faced by sanitary landfills are the safe disposal of waste, the possibility of waste recovery and environmental protection (air and wastewater pollution). This paper analyses the problems of air quality management at the location of the Brijesnicalandfill in Bijeljina and the assessment of the sanitary waste disposal method efficiency based on the analysis of the results of the air quality measurement at the landfill site.

The study presents results of the measurements of the atmospheric nitrogen dioxide concentration and simultaneous meteorological variables: average temperature, air pressure, and relative humidity, speed and wind direction. The data were collected from July 2015 to June 2017 at stations located in Banja Luka (locality Centre). Nitrogen dioxide is one of the major environmental pollutants which has negative impact on plants growth, atmospheric chemistry and climate change. Levels of nitrogen dioxide in air samples and meteorological variables from urban zone of Banja Luka were determined at locality, which is highly populated area, with intensive traffic. The study presents average measured values of nitrogen dioxide, together with maximal and minimal values and relationship between nitrogen dioxide and meteorological variables, i. e. for pollution modelling together with meteorological variables. Statistical analysis confirms string of rolls, which shows directional connection between nitrogen dioxide and meteorological variables. Correlation between nitrogen dioxide and temperature (r= -0.207), wind speed (r= -0.130) and relative humidity (r= -0.048) was negative and significant during the measurement period.

A green chemistry approach for fabrication of active carbon, enriched with remediated iron is shown. Detailed characterization (HRSTEM, STM, and N2 adsorption) was performed, followed by active carbon soaking in iron and manganese ionic solutions obtained from remediated mining sludge. Novel forms of active carbons with round or needle-like oxide particles on the surface were obtained by combining these materials. The materials were tested as filters for sulfur dioxide, on sulfur-rich coals fume. After adsorption, the iron structures seem to play a stronger catalytic role in the filter regeneration, transforming the adsorbed sulfur dioxide into sulfuric acid.

The verification of the blasting parameters of Ammonium Nitrate Fuel Oil (ANFO) with the addition of microstructured charcoal (MC) produced by destructive wood distillation was performed. Additional investigation of specific surface and pore distribution by the nitrogen adsorption of the two granulations of MC was also carried out. High-resolution scanning electron microscopy was used for morphology evaluation and revealed smoothening of the initially developed external surface of carbon with intensive milling. In addition, the analysis of the thermal properties of the studied samples (TG/DSC) indicated that the size of the microstructured charcoal additives influenced the decomposition temperature of the prepared materials. The explosives containing microstructured charcoal grains of −90 μm underwent decomposition at lower temperatures in comparison with those containing higher sizes of microstructure charcoal grains (−1.18 mm), for which the decomposition temperature reached 292 °C. The obtained results of blasting parameters compared to the results derived from thermodynamic simulation showed the non-ideal character of the explosives (much lower values of blasting parameters than in established thermodynamic models). It was indicated that higher velocities of detonations (VOD) were obtained for non-ideal explosives where finer MC grains were added. Blasting tests confirmed that the studied type of MC can be applied as an additive to the ANFO.

Hematite nanoparticles with amorphous, yet relatively uniform carbon shell, were produced based exclusively on the waste sludge from the iron mine as the raw material. The procedure for acid digestion-based purification of the sludge with the full recovery of acid vapors and the remaining non-toxic rubble is described. Synthesis of the hematite nanoparticles was performed by the arrested precipitation method with cationic surfactant. The particles were thoroughly characterized and the potential of their economical production for the battery industry is indicated.

In this study, we examined the influence of microstructured charcoal (MC) when added to ammonium nitrate fuel oil (ANFO) samples. We performed a study that investigated ANFOs structure, crystallinity, and morphology by utilizing infrared spectroscopy (IR), X-ray diffraction (XRD), and scanning electron microscopy (SEM), respectively. MC characteristics were probed by Raman spectroscopy and SEM analysis. SEM analysis indicated how fuel oil (FO) covered ammonium nitrate prill. Moreover, the surface of the MC was covered by specific microfibers and microtubes. The disordered graphitic structure of the MC was also confirmed by Raman spectroscopy. Simulation of blasting properties revealed that the addition of MC should decrease blasting parameters like heat explosion, detonation pressure, and detonation temperature. However, the obtained differences are negligible in comparison with the regular ANFO. All analyses indicated that MC was a good candidate as an additive to ANFO.

Iron oxide nanoparticles are iron-based nanomaterials that are, to date, successfully used in various areas of industry and everyday life. The sustainability of iron is a factor which leads to wide variety of research of the iron oxide roles in industrial catalysis and biomedicine. An industrial catalysis and biomedical applications are here connected, because these two groups of applications demand very similar preparation of materials: shape of the particles and their size, the particular and, as uniform as possible, particle porosity. Further, commonly used synthesis methods are outlined, in order to be able to select the preferred synthesis method according to final desired application of the nanoparticles.