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Potencijalnost ležišta zeolitskih tufova Srbije
No full textVeliki broj pojava i ležišta prirodnih zeolita piroklastičnog porekla su široko rasprostranjeni u miocenskim sedimentima Srbije, od kojih su najznačajniji: Zlatokop (vranjski basen), Igroš, Jablanica 1 (kruševački basen), Općište-Beočin (Fruška Gora), Toponica (Kosovska Kamenica) i Slanci (Dunavski ključ kod Beograda). Ležišta ovih zeolitskih tufova, prostorno i genetski vezana su za vulkanske i vulkanoklastične stene marinskih sredina senonske i neogenske starosti i jezerske sedimente neogene starosti. Ovde će više reči biti o prognoznim resursima naših zeolitskih tufova, kako u odnosu na dosadašnje registrovane pojave, tako i na eventualno potencijalna područja u pogledu pronalaženja novih količina ove ekonomski veoma interesantne mineralne sirovine
Enhanced adsorption of mycotoxin zearalenone by clay-chitosan-surfactant composite
No full textMycotoxins are a large group of highly health-hazardous contaminants which are frequently found in
animal feeds, foods for human consumption and agricultural products. Aflatoxins, ochratoxin A, zearalenone
(ZEN), fumonisins and trichothecenes are the most frequently occurring mycotoxins. Zearalenone is a common
contaminant of corn and possess strong estrogenic activity causing serious reproductive problems in humans
and animals. Various methods (physical, chemical and biological) have been taken to remove mycotoxins
from contaminated animal feed. Among physical methods, adsorption is considered as the most efficient in
treating mycotoxins contamination. Clay minerals (bentonite - BENT) as naturally abundant, green, nontoxic
and low-cost are shown to be effective adsorbents for aflatoxin B1 - AFB1, but they are ineffective in
binding other mycotoxins, like ZEN. In order to increase ZEN adsorption, modification of BENT with organic
molecules such as surfactants is necessary (Lian et al., 2019). Recently, composites of natural biopolymers
(e.g. chitosan) and clays have been studied as adsorbents for AFB1 and ZEN (Wang et al., 2020). Chitosan is
a particularly interesting biomaterial due to its biocompatibility, biodegradability, antimicrobial activity and
adsorption properties. In our previous work, a natural BENT from Beretnica deposit in the Republic of Serbia
was modified with chitosan isolated from mushroom Agaricus bisporus under laboratory conditions - CM
(composite BCM) (Kozarski et al., 2023) and subsequently with surfactant - hexadecyltrimethyl ammonium
bromide in amount equal to 50% of the CEC of BENT (composite BCMS). Both composites were characterized
by Fourier transform infrared (FTIR) spectroscopy and tested as adsorbents of ZEN. Characterization results
confirmed presence of chitosan and/or surfactant in composites. The results on adsorption of ZEN showed that
BCMS composite had a high adsorption of ZEN, while its adsorption by BCM and BENT was low, at pH 3
(Smiljanić et al., 2023). The aim of this research was to further investigate the adsorption of ZEN by BCM
and BCMS composites. Composites were characterized by DSC/TGA analysis and by determination of zeta
potential which additionally confirmed presence of chitosan and/or surfactant in composites. Adsorption of
ZEN was followed at different amounts of composites in suspension at pH 7 and results were compared with
toxin adsorption at pH 3. Adsorption of ZEN by BCM was also low at pH 7, while presence of surfactant in
BCMS significantly increased toxin adsorption. Adsorption of ZEN by BCMS composite was followed at
different initial ZEN concentrations at pH 3 and 7 and its adsorption increased with increasing of the initial
toxin concentration at both pH values. Results confirmed that although surfactant ions in BCMS are responsible
for adsorption of ZEN, composite also contains biocompatible chitosan isolated from mushroom with potential
antimicrobial activity
The importance of sustainable technologies in the field of energy and climate change
No full textThe article analyzes the importance of sustainable technologies with
an emphasis on their two goals, the transformation of the energy sector and the
control of climate change. Large companies and corporations generally base their
business goals on the economic effects and profits that are planned to be realized.
However, the greatest competitiveness on the market in the era of modern business
is ensured exclusively by sustainable technology and economy. In this way, they
contribute to sustainable development not only in the local community, but also
in the wider area. Individual businesses contribute to sustainable development
globally through decisions within their technology management programs. The
analytical approach can be related to the type of products and the technology
that will be applied to obtain them, the type, quantity and origin of the resources
used. The level of investment in research as the basis of process technology and
the use of technology so that it does not endanger the environment is the basic principle of production. It was also requested to improve the overall quality of
life of its employees and members of society in general. Effective sustainable technology
contributes to increasing the economic, environmental and social value
of products. Along with the development of sustainable technologies, there is an
increasing emphasis on the adoption of various directives and the preparation
of studies that indicate the importance of preserving and protecting the environment,
sustainable use of natural resources and energy sources that do not pollute
the working and living space (e.g. solar energy or wind energy). The common
approach and conclusion is that the path of problem solving leads to sustainable
technologies. The World Energy Council indicates the importance of transformation
of the energy sector and the application of sustainable technologies and
the adoption of urgent solutions. The so-called the energy trilemma index that
deals with the three most frequently confronted challenges: energy security, social
impact and environmental issues. The foundations of these challenges are the inextricable
connection between energy security, energy equality and environmental
sustainability, to which all people of the world population have an equal right,
regardless of where and how they live. In the process of solving the problems caused
by climate change, as well as stopping the processes that lead to climate change,
sustainable technologies play a big role. It is rightly stated that the integration of
sustainable technologies into everyday life has a key role in the fight against climate
change. The importance of sustainable and innovative technologies in the fight
against climate change is expressed through three key roles: reducing greenhouse
gas emissions, promoting energy efficiency and mitigating the harmful effects of
climate change. Their role came to the fore especially through the information
and communication sector
Примена електрофоретског таложења за добијање биоактивних композитних превлака на бази хидроксиапатита
No full textPlant growing site characteristics – an important factor for biomass selection
No full textThe characteristics of leaf biomass of invasive Acer negundo L. tree species from three different growing sites were evaluated, and its potential influence for its further usage was considered. Two natural and one mining site were chosen for the sampling of soil and leaves: Mountain Avala (A), Great War Island (B) and the banks of former coal separation pond in Piskanja (C). The results confirmed that soil sample C from the most anthropogenic influenced area, stands out from the other two samples and coresponding biomass differs in terms of physical and chemical characteristics. The amount and proportion of macro elements and surface charge in sample C differes from other two samples. This study confirmed that the growing site characteristics influence the chemical composition of plant biomass, primarily in terms of macro elements composition, important for the further development of specific bio-based materials
Characterization of biochars derived from Myriophyllum Spicatum using Fourier transform infrared spectroscopy
No full textAquatic plants are one type of biomass that has been studied lately due to its potential for commercial use, environmental significance, and bioremediation. Invasive aquatic weeds, when introduced and allowed to spread in aquatic ecosystems, can cause significant environmental and economic harm. Producing biochar from aquatic weeds offers a sustainable solution to managing invasive species while providing significant environmental, economic, and practical benefits. Herein, Fourier transform infrared spectroscopy (FTIR) was used as an analytical tool to analyze the characteristics of three biochars made from the aquatic weed Myriophyllum spicatu
Turning Agricultural Waste into a Powerful Solution: Enhanced Lead Removal via Chemically Modified Oat Straw
No full textThe release of industrial effluents and agricultural runoff containing heavy metals, like lead (Pb), poses
serious environmental risks and significant impact on human health. This study explores the adsorption
capacity of potassium hydroxide (KOH)-modified oat straw (KOS) as an effective, low-cost biosorbent
for lead removal from contaminated water. The modification process increased the surface area and im-
proved the availability of functional groups, enhancing adsorption performance compared to unmodified
oat straw. Structural analysis was conducted using Scanning Electron Microscopy (SEM) and Fourier
Transform Infrared spectroscopy (FTIR). Batch experiments evaluated the effects of contact time, initial
Pb²⁺ concentration, and pH on lead removal efficiency. The adsorption process followed pseudo -second-
order kinetics, with chemisorption as the main mechanism. Isotherm studies indicated that the Langmuir
and Redlich-Peterson models offered the best fit, showing a maximum adsorption capacity of 191.41
mg/g. These findings highlight the potential of KOH-modified oat straw as a sustainable solution for
heavy metal removal from wastewater, effectively valorizing agricultural waste biomass
Developing thermal insulation cement-based mortars with recycled aggregate in accordance with Net Zero principles
No full textThe performance of thermo-insulation rendering mortars with alternations in ratios
of powdered cordierite and talc was examined. The goal was to confirm that recycled
kilnware cordierite can be reapplied in the mortar design without significant deterioration in
performance in comparison with OPC mortar. Differential thermal analysis was employed for
examining thermally induced reactions. The cavitation erosion, in testing sequences ranging
from 30 to 120 minutes, was used to assess the compactness of the mortar structure. The
physico-mechanical properties of experimental mortars were investigated. The morphologies
of the mortar tablets upon cavitation were studied using a scanning electron microscope. It
was established that cordierite and talc filler in amounts up to 20% enhance microstructural
packing and mechanical strengths due to improved cementation and therefore contribute to
cavitation erosion resistance. Higher amounts of talc cause structural degradation and mass
loss during cavitation tests. Reducing manufacturing costs, energy consumption, and
greenhouse gas emissions are the main objectives of the production of this waste-based
construction composite, as the reuse of waste materials can help achieve a number of
Sustainable Development Goals
EIT Raw Materials RIS-DUSTREC: investigation and selection of furnace dust samples for valuable metals recovery
No full textEvery year around 1.2 Mt of Electric Arc Furnace (EAF) dust and around 50 kt of Cupola Furnace (CF) dusts are generated
in Europe. Both materials are classified as hazardous waste due to significant concentration of Zn, Cd, Cr, Ni and Pb, which burden the metallurgical industry, albeit their possibility to be considered as an alternative source of valuable metals. Around 30 steelworks in the East-Southeast European Regional Innovation Scheme (ESEE RIS) region exploit EAFs for scrap-based steelmaking. However, the dusts generated from the exhaust gases abatement cannot be profitably recycled due to the absence of recycling plants operating in these areas, which implies that the dust generators have additional costs due to the dust ransportation to the nearest Zn recovery plant, since presence of toxic substances prohibits their landfilling. Thanks to the extensive knowledge on the extraction of a wide range of compounds from steelmaking dusts, as well as the capacity of reutilisation of residues after extraction in the building and construction industry, the DustRec project aims at the recovery of all the economical compounds within the dusts (Zn, Pb, Cu, Fe and others) hence minimizing the final waste landfilling and generate an economically feasible process with improved environmental and societal impacts. The proposed approach includes several emerging techniques from innovative magnetic and gravity separation methods to new pyro- and hydro-metallurgical reprocessing technologies for the separated fractions. In this paper, eight different dusts from EAF and CF were collected all around the partners’ countries and chemically, thermally and physically characterized in order to select the most optimal samples to be reprocessed for improved valuable extractions. Due to their high concentration of ZnO and PbO, three EAF dusts were identified as promising raw materials while two CF dusts will be employed as co-adjuvant for magnetic
fraction reduction and smelting. Preliminary hints about the next reprocessing steps are also revealed
Trajno rešavanje problema letećeg pepela iz termoelektrana vezivanjem za elementarni sumpor
No full textLignite is the basic raw material used by thermal power plants in Serbia to
produce electricity. In the process of burning coal, ash appears as a secondary product for
17% (data from the Nikola Tesla Power Plant). Fly ash, which is an ultrafine ash content,
causes air, water, and soil pollution, and is the main cause of a significant increase in the
number of various diseases among the surrounding population. A chemical analysis of fly
ash samples from the Nikola Tesla thermal power plant in Obrenovac was performed, and
results were obtained that inevitably require a reaction in terms of eliminating the components found in this product. The presence of heavy metals was established: Zn, Cr, Cd, Sr, Pb, Co
and Ni. Despite the fact that these elements are difficult to dissolve in water, they led to
serious environmental pollution, which eventually led to very serious health complications,
primarily in the population living directly next to the thermal power plant. The air very easily
disperses this fly ash, and besides it pollutes water and soil, not only in the surroundings
but also on a larger surface of the land, the particles carried by the wind spread to areas
that are more distant. The toxicity of these heavy metals is particularly dangerous due to
their cumulative deposition in the human body, which is the last in the food chain, and is
in direct danger due to the presence of fly ash from the air, water and soil, through cultivated
agricultural products. This is a very complex problem, which is the subject of research
and finding solutions in many countries. At the same time, elemental sulfur appears as a
secondary product of oil refining. By applying sulfur in the process of homogenization and
agglomeration of ash in amounts from 15% to 22%, coating and increase of ultrafine ash
particles <63мm in size is achieved and their presence is reduced from 17.5% to 1%. The
product obtained in this way can easily and without additional investment be disposed
of in landfills without the possibility of polluting the environment. This would prevent and
significantly reduce environmental pollution, as well as further illness of the population due
to the influence of the presence of fly ash. It would also solve the problem of sulfur disposal
as a secondary product of oil refineries. The resulting agglomerate of ash and sulfur could
be further used in construction