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Advanced technology for photocatalytic degradation of thiophanate-methyl: Degradation pathways, DFT calculations and embryotoxic potential
No full textThis study focuses on establishing an efficient two-step technology, which includes: (1) consecutive adsorptiondesorption,
using cellulose-based membranes, bCells, and (2) photocatalytic degradation of the fungicide
thiophanate-methyl (TPM), using synthesized Ag-P25 and Ce-P25 catalysts. The catalysts, obtained by
controlled deposition of Ag2O/Ag and CeO2 onto P25 TiO2 carrier (Degussa), were characterized using ATRFTIR,
XRPD, BET, FESEM, HRTEM, HAADF-EDS and UV–DRS techniques. In order to establish a feasible purification
technology, preconcentration of TPM was performed by adsorption, achieving 75.5 and 92.9 mg/g of
TPM removal using bCell-EpL and bCell–EpL–TA membranes, respectively, followed by efficient desorption (>
95%) that provided acceptable TPM concentration for photodegradation experiments. Under optimal conditions
(0.07 g/L of both catalysts), complete degradation of TPM (5 mg/L) occurred within 2 h, compared to 4 h for the
base TiO2 P25. Measurements of quantum yield and the results of HPLC-MS analysis, alongside DFT calculation,
assisted in understanding the TPM degradation pathways. New degradation products were detected and proposed
from HPLC–MS analysis. Embryotoxic assays, performed on zebrafish (Danio rerio), applied to estimate the
toxicity evolution of time-dependent generated TPM degradation products, showed low embryotoxic potential.
Chemical oxygen demand (26 mg O2/L) confirmed low ecotoxicological pressure of effluent water
Oxide Powder Mixture with Poly-vinyl Alcohol (PVA) and added Polyethylene Glycol (PEG) as Plasticizer
No full textPowder mixture consisted of ZnO, Mn2O3 (MnCO3) and Fe2O3 blended powders, was found laminating during compaction. Polyvinyl alcohol (PVA) and a combination of PVA with polyethylene glycol (PEG) added as a plasticizer, were introduced as polymer binders to improve the compaction of oxide mixtures. It has been done by forming a suspension of oxide mixture and varying the polymer solution concentration and composition. By evaporating the solvent, new materials were obtained, which consist of oxide particles bound via polymer. In such a manner obtained hybrid materials were characterized with attenuated total reflection Fourier transformed infrared (ATR-FTIR) spectroscopy, differential thermal analysis (DTA) and transmission electron microscopy (TEM). The oxide polymer material was compacted at 200 MPa and the expansion of this compact during heating was monitored in temperature range up to 550ºC with dilatometer. It was found that PVA forms graft polymer with PEG and specific interaction with oxide particles surface was revealed.Смеша прахова састављена од ZnO, Mn2O3 (MnCO3) и Fe2O3 комбинације
прахова је показивала ламинацију током пресовања. Поливинил алкохол (PVA) и
комбинација PVA са полиетилен гликолом (PEG) који је додат као пластификатор, су
уведени као полимерно везиво за пресовање оксидних прахова. Везиво је уведено тако
што је формирана суспензија смеше различитих оксида прахова у полимерном
раствору. Концентрације полимера и састави су варирани. Уклањањем растварача
добијени су нови материјали који се састоје од честица оксида повезаних полимерима.
Ови хибридни материјали окарактерисани су методама ометене тоталне рефлексије
фурије трансформисане инфрацрвене спектроскопије (ATR-FTIR) као и
диференцијалне термичке анализе (DTA). Микроструктура је посматрана
трансмисоном електронском микроскопијом (TEM). Оксид-полимер материјали су
пресовани на притиску од 200 MPa и ширење испреска током грејања је праћено у температурском опсегу од собне до 550ºC употребом дилатометра. Нађено је да PVA
формира графт полимер са PEG и да постоји специфична интеракција полимера са
површином честица оксида
Foam glasses made from green bottle glass and sugar beet factory lime as a foaming agent
No full textGreat waste production alongside limited natural resources represents huge environmental and economic problems worldwide. Sustainable waste management and industrial production can reduce pollution and gain some economic benefits. Eco-friendly thermal insulators such as foam glasses can be produced using secondary raw materials in open-loop recycling. Foam glasses were successfully produced using green bottle glass and sugar beet factory lime (SBFL), CaCO3-rich waste as a novel foaming agent. Glass powder was mixed with different amount of SBFL, uniaxially pressed at 20 MPa, and sintered at different temperatures. The influence of sintering temperature and the addition of a foaming agent was examined. Obtained samples were mechanically, thermally, and microstructurally characterized. Results showed that samples sintered at 800 °C have the best properties. Obtained foam glasses can be used in a variety of industries where thermal insulation, non-flammability, and non-toxic materials are required
EU pojekti - Mogućnost i šansa za uključivanje i angažman naučnih kadrova iz geologije i rudarstva (posebno PMS-struke). sa osvrtom na projekat RIS-DUSTREC-II NO 22009 iz oblasti Eit Raw Materials (sekundarnih sirovina)
No full textVelike količine prašine iz EAF peći se stvaraju u Evropi (1,3Mt), kao i u svetu (8,764Mt). Zbog visokog sadržaja Fe i Zn, čiji sadržaj često dostiže ukupno između 50 i 60 tež.%, EAF prašina je oduvek bila interesantna za reciklažu. Do sada, najčešće primenjivana metoda prerade EAF prašine je pirometalurški proces ekstrakcije Zn u Waelz pećima (85% tržišnog učešća). U radu je predstavlјen EIT Raw Materials projekat: RIS-DustRec-II, koji ima za cilј razvoj inovativnih tehnologija za odvajanje, ponovnu obradu i korisnu upotrebu svih komponenti EAF i CF prašine iz peći, kako bi se smanjila količina toksičnog otpada i postigla nulta vrednost. –što je cilj za otpad u EU. Urađene su I predstavlјene hemijske, XRD i SEM analize na dva odabrana uzorka prašine EAF i CF peći iz Italije
Polimorfne promene materije nastale mlevenjem minerala
No full textU radu su prikazani rezultati istraživanja iz oblasti usitnjavanja, sakupljani duži niz godina, u Institutu za tehnologiju nuklearnih I drugih mineralnih sirovina. Poznato je da se područja sa frekfencijama preko 3•1011 do 3•1014 Hz nalaze u elektromagnetnom spektru infracrvenog i daleko infracrvenog emitovanog ili apsorbovanog zračenja. U radu su prikazani rezultati kada se materijal i kugle u mlinu nalaze na jednoj od pomenutih frekfencija, što nam omogućava da pomoću Borovog uslova frekfencija pristupimo izračunavanju emitovanih i apsorbovanih molarnih energija. Polimorfne promene materije pri usitnjavanju su promene izazvane fizičkim procesima, odnosno emitovanjem određene količine energije od strane mlina I adsorbovanjem tih energija od strane materijala. Izvršen je pokušaj da se odrede nivoi tih energija. Prikazani rezultati pokazuju da sve jedinke u mlinu pretrpe lokalni pritisak i tada na njima, delimično ili u celini, dolazi do polimorfnih promena materije menjajući fazna stanja i kristalnu strukturu iste. Na zrnima minerala na veoma ograničenim mestima po površini (10-3 do 10-5 cm2) i u kratkim vremenskim periodima trajanja (10-4 s) dolazi do povećanja temperature čak do 1000 C što su autori iz reference [3] nazvali magma plazma modelom slika 1. Rad prikazuje praćenje polimorfnih promena materija preko promena njihovih termodinamičkih veličina. Takođe, postoje i velike razlike polimorfnih promena minerala u zavisnosti od mineraloškog oblika u kojem se materija nalazi
Aromatic plant-based phytoremediation: socio-economic and agricultural stability
No full textAn ever-increasing industrially polluted site is one of the main global concerns in an anthropogenic era. The key challenge is to search for a cost-effective and sustainable approach that is acceptable world level. In this direction, the phytoremediation area is gaining attention globally due to having a high potential to decontaminate polluted sites. Over 20 years of scientific progress in phytoremediation, its reliability among stakeholders and practitioners has not yet been attained, because they are not sure about its applicability and sustainability. However, valuable plant-based phytoremediation is emerging fast due to its socioeconomic, ecological, and agricultural sustainability. In this regard, aromatic plant-based phytoremediation has wide scope in the era of ever-increasing industrial polluted sites. Aromatic plants are well recognized for their societal and economic significance from the ancient to the modern era. Some aromatic grasses are famous for their work as nurse plants that are capable of restoring ecosystem services as well as driving succession in poor environments at the beginning of restoration. Therefore, Aromatic Plant-Based Phytoremediation has tremendous potential to remediate worldwide wide-ranging polluted sites. The present book is useful for researchers, ecological engineers, policymakers, stakeholders, and practitioners to select specific aromatic plant species according to the site-specificity of the polluted site. This book offers some potential opportunities in aromatic plant-based phytoremediation as phytoproducts, i.e., essential oil (bio-economy) while restoring polluted sites. It also provides knowledge and insights about the phytoremediation potential of aromatic plants. It is the first book “Aromatic Plant-Based Phytoremediation” that brings together new and established knowledge on different aspects of aromatic plants in phytoremediation, providing these facts in a single source that deals with an innovative fusion of scientific and experiential knowledge on polluted site restoration.
In addition, the changing environment also causes various biotic and abiotic stresses in aromatic plants and thus adversely affects the growth and yield of aromatic plants. So, the application of climate-resilient aromatic plants in phytoremediation programs by using agro-biotech applications is of utmost importance to lessen environmental pollution. Soil amendments, microbial inoculation, tolerant aromatic plants, and genome engineering have been used to enhance phytoremediation in harsh conditions. There is no such kind of book that is available on the market that can cover such a novel topic as “Aromatic Plant-Based Phytoremediation”. It is an up-to-date and timely contribution that delivers a holistic approach for carrying out phytoremediation with socio-economic, ecological, and agricultural profits, benefitted by simple to understand and easy-to-read format. The present book will deliver a superb basis from which scientific facts can nurture and widen the fields of aromatic plant-based phytoremediation
Influence of natural minerals on contaminated solutions pH values
No full textThe protection and arrangement of agricultural areas in order to obtain health-safe food is extremely important to know the mobility of heavy metals lead, cadmium, zinc and uranium as radionuclides. This research investigated the influence of mineral raw materials (apatite and zeolite) on the mobility of heavy metals and radionuclides in a column system with constant pressure at different pH values (5.0 and 7.0). The tested solutions were contaminated with metals (lead, cadmium, zinc and uranium), in a concentration of 300 mg/l in time intervals of 30, 60, 90, 120 and 180 minutes. It was experimentally determined that there were significant changes in the pH value of the filtrate. The results showed that both apatite and zeolite successfully immobilized lead at both pH values. Uranium immobilization was better performed in columns with apatite, zeolite showed better properties in cadmium immobilization, and tests on a solution contaminated with zinc showed that both apatite and zeolite show similar affinity. The obtained results were statistically processed using the method of two-factor analysis of variance with repeated measurements. Further research will be based on monitoring the morphophysiological properties of underground and aboveground parts of plants on contaminated soil samples when apatite and zeolite are applied
Foam glasses made from waste flat glasses and sugar beet factory lime with the addition of borax and water glass
No full textFoam glass is a lightweight and high-strength material that can be used for thermal and acoustic insulation. Foam glass with suitable properties for use as an insulating material was prepared using waste flat glass, a glass waste not normally used for the production of glass foam, and sugar beet factory lime (S), a CaCO3-rich waste, as a novel foaming agent.Three mixtures were prepared: Glass powder mixed with S (FG-S), glass powder mixed with S and borax (FG-S-B), and glass powder mixed with S and water glass (FG-S-WG). The mixtures were homogenized, pressed into pellets in a hydraulic press, and foamed at 800 °C for 30 min. The prepared samples were characterized mechanically, thermally, and microstructurally. All samples exhibit very low crystallinity. FG-B has the lowest total porosity but much higher compressive strength than FG-S and FG-S-WG. In addition to the total porosity, the pore size distribution of the samples also has a strong influence on the compressive strength. FG-S-B has smaller pores compared to FG-S and FG-S-WG, where the intense foaming of S and water glass leads to the rupture of the pore walls and their coalescence. The thermal conductivity follows the same trends as the total porosity. FG-S and FG-S- WG have a thermal conductivity of 0.044 W/m.K and FG-B has 0.059 W/m.K. All samples have good thermal properties as insulators, but FG-S-WG has poor mechanical properties
Jarosite sludge - utilization and valuable metals recovery applying roasting-leaching process
No full textDuring the conventional roast–leach–electrolysis (RLE) zinc production process,
precipitation of the jarosite-type compounds is widely used to remove iron and other metal
impurities from the solution. Above mentioned compounds, with the general formula
MFe3(SO4)2(OH)6, (M+=NH4, Na, K, Ag, etc.), in addition to iron, contain a high
concentration of Pb, Cd, Cr, As, Zn, In, Ga, Ge as metal oxides and/or sulfates [1].
Consequently, jarosite is considered hazardous yet valuable waste [2]. In addition, every
year around 6-7 million tonnes of jarosite waste is generated globally [3]. Due to large waste
volumes and its chemical characteristics, jarosite requires a lot of storage space and
monitoring. Unfortunately, this type of waste is often landfilled causing serious
environmental problems and irreversible metal and value losses. Hence, an urgent solution
for both managing and utilization/recycling is required, to face needs regarding ecological
demands and circular economy goals.
In this paper, jarosite sludge, as a specific type of hazardous industrial waste, is used
to investigate transformation to the targeted compounds through the comprehensive
thermodynamic analysis and experimental roasting process tests. The roasting was
conducted to transform iron into insoluble hematite (Fe2O3), valuable metals (Zn, Cu, and
In) into water-soluble sulfates, and to keep Pb in the form of water-insoluble anglesite
(PbSO4). The solid residue obtained after roasting was used in leaching tests to further
evaluate the efficiency of the targeted phase transformations.
Theoretical considerations of chemical reactions and phase thermodynamics were
performed using the HSC Chemistry v.9.2.3 software [4] to define potential chemical
reactions, examine the feasibility of the target transformations, and set the limiting reaction
parameters. Further, in the first part of the experimental work, the influence of the roasting
process and reaction parameters on the transformation of jarosite sludge phases into target
compounds was investigated. This included variations in the reaction time, temperature, and
furnace atmosphere influence. The leaching conditions were kept constant (temperature of
25 °C, during 60 min, and solid to liquid ratio of 1/5) to determine the efficiency of phase
transformations in the samples obtained by roasting. Changes in the chemical and
mineralogical composition and microstructure were analyzed using different analytical
methods, including XRD and SEM analysis.
According to the obtained results of the roasting process, it was determined that the
phase transformation of jarosite sludge compounds into targeted insoluble hematite and
water-soluble sulfates occurs at 730 °C, the time required is 60 min in the air (oxidizing) atmosphere of 1-2 [dm3/h]/kg of the input material, which is in accordance with the results
of the theoretical indications. Also, it is experimentally confirmed that the introduction of
sulfate into the roasting atmosphere leads to the incomplete transformation of jarosite and
the formation of the unwanted Fe2(SO4)3. Leaching results of the sample obtained by the
abovementioned optimal roasting conditions show that only 4.5 % of Fe is leached while
the rest remains as solid targeted hematite. Also, more than 75 % of In and more
than 90 % of other targeted metals (Cu and Zn) are leached, indicating the high efficiency
of the roasting process. Phase transformation was confirmed by SEM analysis, showing that
hexagonal crystals of jarosite, dominating in the starting material, were completely replaced
with the globular microstructure of Fe2O3, in the roasted samples. SEM analysis of the
leaching residue also confirmed the absence of the water-soluble sulfates and the presence
of the anglesite as water-insoluble sulfate. The phase composition of the samples is
confirmed by XRD analysis.
This research shows that the proposed process enables the recycling of jarosite through
metal transformation and further utilization. The obtained products can be used in industry,
while the metal ions can be selectively separated from the sulfate solution and returned to the
production streams. This approach contributes to the utilization of jarosite, as hazardous
waste, in order to obtain valuable metals, and generally reduces the negative environmental
impact by decreasing the amount of disposed waste and reducing the need for primary
exploitation
Investigation of the possibility of valorization of two borate samples from the deposit "Pobrđe" – Baljevac
No full textBoron is a rare element from the group of non-metals and it occurs in nature in over 250
boron-bearing minerals-borates. Turkey has the largest borate reserves and is their largest producer.
Serbia has significant borate resources, for now without exploitation and processing. This paper presents
the results of investigating two borate samples from the deposit ""Pobrđe. The following properties were
determined on borate samples: free and hygroscopic moisture, granulometric composition, chemical
composition, mineralogical analysis by size classes, and XRD analysis