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U XXI veku uobičajeni obrazac ponašanja ljudi uključuje provođenje u proseku 20h dnevno u zatvorenom prostoru i shodno tome malo vremena na otvorenom. Ovaj obrazac ima za posledicu mnoge hroniče bolesti ali i poseban značaj za alergijske bolesti. Povećane temperature mogu povećati populaciju grinja ili bubašvaba, i nameštaj će postati rezervoar akumuliranih alergena unutar kuće. Dok su alergije ranije bile redak zdravstveni poremećaj, danas epidemiološka istraživanja pokazuju da oko 25% ukupne svetske populacije boluje od neke alergijske bolesti. Uprkos razvoju farmakoterapije broj obolelih se svake godine povećava, i ima tendenciju daljeg rasta u svim starosnim kategorijama. U Evropi, prema podacima EAACI (The European Academy of Allergy and Clinical Immunology), više od 150 miliona građana pati od hroničnih alergijskih bolesti.. Procenjuje se da će do 2025. godine više od 50% stanovnika Evrope patiti od alergijskih bolesti. U Institutu za virusologiju, vakcine i serume “Torlak” u Beogradu se proizvode alergenski ekstrakti koji se koriste za in vivo dijagnostiku i alergensku imunoterapiju (AIT). Prema dostupnim podacima grinje su jedan od najučestalijih inhalatornih alergena u Srbiji. Cilj ovog master rada je bio da se ispita uticaj različitih ekstrakcionih procedura na kvalitet ekstrakta kao i da se odredi sadržaj ključnih – major alergena. Korišćena su 3 različita puferska rastvora određenih koncentracija za ekstrakciju glavnih (major) alergena Dermatophagoides pt. na različitim temperaturama, a zatim je imunohemijskim metodama poređena njihova efikasnost. Dobijeni rezultati pokazuju da je ekstrakcija 0,15 M fosfatnim puferom na temperaturi 2-8°C najefikasnija za dobijanje većih količina Der p1 i Der p2 alergena.

Termin pektin se odnosi na strukturno najsloženiju porodicu polisaharida u prirodi. Nalazi se u ćelijskom zidu biljaka. Jako je značajan po svojoj sposobnosti da poboljša kvalitet hrane. Njegova izvanredna struktura i svojstva su doprinela da se dosta koristi kao stabilizator i zgušnjivač. Prvo pominjanje pektina je u jednom Engleskom članku 1750. godine o pripremi želea od jabuka. Francuski hemičar i farmaceut, Henri Braconnot je 1825. god. izolovao i opisao ovo jedinjenje. Kada govorimo o komercijalnoj proizvodnji, 1930-ih godina Hermann Herbstherith je pisao o mogućoj upotrebi jabukovih komina koje su se odbacivale kao nusproizvod u proizvodnji voćnog soka. Naziv pektin potiče od grčke reći „pektos“, što znači čvrst i tvrd i ukazuje na sposobnost pektina da formira hidrogel. Sadržaj pektina varira u zavisnosti od izvora biljnog materijala. Postoji nekoliko nusproizvoda poljoprivredne i prehrambene industrije koje imaju visok sadržaj pektina: komine od jabuka, šećerna repa, suncokret itd. Pektin je jako bitan u ljudskoj ishrani jer predstavlja prebiotsko i rastvorljivo dijetetsko vlakno, deluje tako što smanjuje koncentracuju glukoze u krvi, koncentraciju LDL holesterola, imunostimulišuće i antikancerogeno. Cilj ovog završnog rada je bilo ispitivanje antioksidativnih osobina kiselih i alkalih hidrolizata pektina iz kore i pulpe dunje.

Here, we report the design of a disposable single-drop voltammetric sensor for the quantitative determination of antipsychotic drug trifluoperazine (TFP). The sensor was built using inkjet-printed carbon nanotube (CNT) electrodes, which were modified with dimercaptosuccinic acid (DMSA)-coated magnetite nanoparticles uniformly dispersed over reduced graphene oxide nanosheets (DMSA/Fe3O4/RGO). The used modifying materials were characterized by electron microscopy techniques (transmission electron microscopy (TEM) and field emission-scanning electron microscopy (FE-SEM)), X-ray powder diffraction, ζ-potential measurements, dynamic light scattering (DLS), and electrochemical methods (cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS)). The developed sensor, best operated at pH 7 in the Britton-Robinson buffer solution (BRBS), shows linear electrocatalytic activity with TFP in the concentration range of 1-50 μM, a low detection limit of 0.54 μM, and excellent selectivity, repeatability, and reproducibility with an relative standard deviation (RSD) of 2.4%. A voltammetric approach using square wave voltammetry (SWV) is a sensitive technique under optimized conditions for the analytical determination of submicromolar amounts of TFP. Bare CNT and RGO- and DMSA/Fe3O4-modified CNT electrodes showed lower electrocatalytic activity than the DMSA/Fe3O4/RGO/CNT electrode. The development of this kind of TFP sensor based on nanoparticle-decorated graphene nanosheets can offer a tool for point-of-care applications as sensors in biomedicine.

An electrochemical sensor is described for the determination of L-dopa (levodopa; 3,4-dihydroxyphenylalanine). An inkjet-printed carbon nanotube (IJPCNT) electrode was modified with manganese dioxide microspheres by drop-casting. They coating was characterized by field emission scanning electron microscopy, Fourier-transform infrared spectroscopy and X-ray powder diffraction. The sensor, best operated at a working voltage of 0.3 V, has a linear response in the 0.1 to 10 μM L-dopa concentration range, a 54 nM detection limit, excellent reproducibility, repeatability and selectivity. The amperometric approach was applied to the determination of L-dopa in spiked biological fluids and displayed satisfactory accuracy and precision. [Figure not available: see fulltext.]. © 2019, Springer-Verlag GmbH Austria, part of Springer Nature.

A disposable acetaminophen biosensor based on inkjet-printed CNT electrodes (IJPCNT) modified with amidase/cerium dioxide@graphene nanoribbons composite was developed (ACeO2@GNR/IJPCNT). The enzyme amidase A was used for the first time as a recognition element. Inkjet-printed CNT electrodes served as a basis for the construction of a biosensor that enables droplet detection using 5 μL sample volume. The biosensor showed high selectivity, sensitivity, a low detection limit of 0.18 μM and a wide working linear range from 1 to 100 μM. The proposed approach allows fast and reliable detection of acetaminophen in biological fluids with negligible matrix effect and remarkable reproducibility. © 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

A disposable acetaminophen biosensor based on inkjet-printed CNT electrodes (IJPCNT) modified with amidase/cerium dioxide@graphene nanoribbons composite was developed (ACeO2@GNR/IJPCNT). The enzyme amidase A was used for the first time as a recognition element. Inkjet-printed CNT electrodes served as a basis for the construction of a biosensor that enables droplet detection using 5 μL sample volume. The biosensor showed high selectivity, sensitivity, a low detection limit of 0.18 μM and a wide working linear range from 1 to 100 μM. The proposed approach allows fast and reliable detection of acetaminophen in biological fluids with negligible matrix effect and remarkable reproducibility.

Nicotine degradation efficiency in water solutions was studied using a water falling film dielectric barrier discharge (DBD) reactor. Two different treatments were applied: direct treatment, the recirculation of the solution through a DBD reactor, and indirect treatment, the bubbling of the gas from the DBD through the porous filter into the solution. In a separate experiment, samples spiked with nicotine in double distilled water (ddH(2)O) and tap water were studied and compared after both treatments. Furthermore, the effects of the homogeneous catalysts, namely, Fe2+ and H2O2, were tested in the direct treatment. Nicotine degradation efficiency was determined using high-performance liquid chromatography. A degradation efficiency of 90% was achieved after the direct treatment catalyzed with Fe2+. In order to analyze the biodegradability, mineralization level, and toxicity of the obtained solutions, after all degradation procedures the values of the following parameters were determined: total organic carbon, chemical oxygen demand, biochemical oxygen demand, and the Artemia salina toxicity test. The results showed that an increase in biodegradability was obtained, after all treatments. A partial nicotine mineralization was achieved and the mortality of the A. salina organism decreased in the treated samples, all of which indicating the effective removal of nicotine and the creation of less toxic solutions. Nicotine degradation products were identified using ultrahigh-performance liquid chromatography coupled with a linear ion trap Orbitrap hybrid mass spectrometer and a simple mechanism for oxidative degradation of nicotine in non-thermal plasma systems is proposed.

The electric power system of the Republic of Serbia relies mostly on lignite-fired thermal power plants, with 70% of the total electricity generation. Most of these plants are over 30 years old, and investment in their modernization is necessary. The energy efficiency of the 110 MW coal-fired power plant in which the condenser is cooled by the mechanical draught wet cooling towers system is analyzed in this paper. Attention is primarily devoted to operating conditions of the cold end of the plant, i.e. to the interrelationship of the condenser and cooling towers. Most important parameters that affect the operation of the cooling towers system are ambient air temperature and relative humidity, specific mass flow rate, and temperature of cooled water. With the existing cooling system, the overall energy efficiency of the plant is low, especially in the summer months, even less than 30%, due to adverse weather conditions. By upgrading existing cooling tower system by adaptation of two additional cooling tower cells, overall energy efficiency can be increased by 1.5%. The cooling tower system rehabilitation investments payback period is estimated to be less than one year. Static method for economic and financial assessment is used.

A thermal power plant (TPP) uses large amounts of fresh water, mostly for cooling purposes. Among different types of cooling systems, once-through cooling is the most water-intensive and has the greatest environmental impacts. From the view-point of the steam cycle efficiency, this type of cooling still provides the most efficient electricity production, and therefore is widely used. Water is withdrawn from nearby water bodies, absorbs heat from the steam in a condenser, and then discharged back to its original source at higher temperatures causing severe environmental impacts, including fish killing, disturbing ecosystems, and heating-up natural water bodies. The total installed capacity of almost 1100 MW on the right bank of the Danube in Serbia threatens the ecosystem of this large international river due to thermal pollution. This problem will be even more pronounced in the near future, due to an inevitable increase in production capacity for new 350 MW, currently under construction. Herein, analysis of the legal framework for the protection of water from thermal pollution as well as analysis of the actual situation on the site of the TPP "Kostolac" in Serbia are presented. Based on meteorological and hydrological parameters, configuration and operation parameters of the plant, the numerical simulation of the condenser was carried on. The temperature of the water leaving condenser and amount of heat discharged back to the river are obtained. According to those results, the analysis of the existing thermal pollution of the Danube River in the flow through Serbia is given by numerical simulation using software ANSYS CFX. Analysis of thermal discharge into the Danube for the five-year period has been carried out. The cooling water effluent causes a temperature increase in the area of the right bank of the Danube, and this thermal disturbance extends along the right river bank for kilometers. Note that the flow rate of the Danube is currently large enough to compens

The formation of hydroxyl radical and long-living chemical species (H2O2, O-3, NO3- and NO2-) generated in the liquid phase of a water falling film dielectric barrier discharge in dependence on the gas atmosphere (air, nitrogen, oxygen, argon and helium) was studied. The chemical molecular probe dimethyl sulfoxide was employed for quantification of. OH, and the influence of hydroxyl radical scavenging on formation of reactive oxygen and nitrogen species was investigated. In addition to liquid analysis, plasma diagnostics was applied to indicate possible reaction pathways of plasma-liquid interaction. The highest. OH production rate of 1.19 x 10 (5) mol l (1) s (1) was found when water was treated in oxygen, with a yield of 2.75 x 10(-2) molecules of. OH per 100 eV. Formation of hydrogen peroxide in air, nitrogen and argon discharges is determined by recombination reaction of hydroxyl radicals, reaching the highest yield of about 0.7 g kWh(-1) when distilled water was treated in argon discharge. Ozone formation was dominant in oxygen and air discharges. Strong acidification along with formation of reactive nitrogen species was detected in water treated in air and nitrogen discharges.

Electricity is a key energy source in each country and an important condition for economic development. It is necessary to use modern methods and tools to predict energy consumption for different types of systems and weather conditions. In every industrial plant, electricity consumption presents one of the greatest operating costs. Monitoring and forecasting of this parameter provide the opportunity to rationalize the use of electricity and thus significantly reduce the costs. The paper proposes the prediction of energy consumption by a new time-series model. This involves time series models using a set of previously collected data to predict the future load. The most commonly used linear time series models are the AR (Autoregressive Model), MA (Moving Average) and ARMA (Autoregressive Moving Average Model). The AR model is used in this paper. Using the AR (Autoregressive Model) model, the Monte Carlo simulation method is utilized for predicting and analyzing the energy consumption change in the considered tobacco industrial plant. One of the main parts of the AR model is a seasonal pattern that takes into account the climatic conditions for a given geographical area. This part of the model was delineated by the Fourier transform and was used with the aim of avoiding the model complexity. As an example, the numerical results were performed for tobacco production in one industrial plant. A probabilistic range of input values is used to determine the future probabilistic level of energy consumption.

Composite material Zr-doped TiO2, suitable for the removal of arsenic from water, was synthetized with fast and simple microwave-hydrothermal method. Obtained material, Zr-TiO2, had uniform size and composition with zirconium ions incorporated into crystal structure of titanium dioxide. Synthetized composite material had large specific surface area and well-developed micropore and mesopore structure that was responsible for fast adsorption of As(III) and As(V) from water. The influence of pH on the adsorption capacity of arsenic was studied. The kinetics and isotherm experiments were also performed. The treatment of natural water sample containing high concentration of arsenic with composite material Zr-TiO2 was efficient. The concentration of arsenic was reduced to the value recommended by WHO.

The aim of this study was to investigate the degradation of the non-ionic surfactant Triton X-100 (TX-100) by using an advanced oxidation process in a non-thermal plasma reactor based on water falling film dielectric barrier discharge (DBD). The effects of two catalytic plasma systems, Fe2+/DBD and H2O2/DBD, were tested to improve the degradation of TX-100 and the mineralization efficiency in the DBD reactor. Both catalytic systems exhibited significant improvements in degradation efficiency, especially in the beginning of the treatment: the efficiency increased from 23 to 88 and 50%, for 5 mgL(-1) Fe2+/DBD and 10 mmol L-1 H2O2/DBD, respectively. The mineralization efficiency of TX-100 in the non-catalytic DBD treatment was very low (1%), but with addition of catalysts, the mineralization efficiency was drastically improved, with H2O2/DBD at 4-34% (depending on the H2O2 concentration) and Fe2+/DBD at 2-21% (depending on the Fe2+ concentration). Degradation products of TX-100 in non-catalytic and two catalytic systems were identified using UHPLC-Orbitrap-MS. Based on the degradation products that were identified, a simple mechanistic scheme was proposed. MS analysis revealed that degradation of TX-100 in the DBD reactor occurred by shortening the ethoxy chain. In the presence of catalysts, there are additional reactions of cleavage of the alkyl chain followed by formation of polyethoxylated phenol (H2O2/DBD) and addition of OH center dot radicals onto the aromatic ring (Fe2+/DBD). The final degradation products did not cause any significant toxic effects to Vibrio fischeri or Artemia salina.

The aim of this study was to investigate the degradation of the non-ionic surfactant Triton X-100 (TX-100) by using an advanced oxidation process in a non-thermal plasma reactor based on water falling film dielectric barrier discharge (DBD). The effects of two catalytic plasma systems, Fe2+/DBD and H2O2/DBD, were tested to improve the degradation of TX-100 and the mineralization efficiency in the DBD reactor. Both catalytic systems exhibited significant improvements in degradation efficiency, especially in the beginning of the treatment: the efficiency increased from 23 to 88 and 50%, for 5 mgL(-1) Fe2+/DBD and 10 mmol L-1 H2O2/DBD, respectively. The mineralization efficiency of TX-100 in the non-catalytic DBD treatment was very low (1%), but with addition of catalysts, the mineralization efficiency was drastically improved, with H2O2/DBD at 4-34% (depending on the H2O2 concentration) and Fe2+/DBD at 2-21% (depending on the Fe2+ concentration). Degradation products of TX-100 in non-catalytic and two catalytic systems were identified using UHPLC-Orbitrap-MS. Based on the degradation products that were identified, a simple mechanistic scheme was proposed. MS analysis revealed that degradation of TX-100 in the DBD reactor occurred by shortening the ethoxy chain. In the presence of catalysts, there are additional reactions of cleavage of the alkyl chain followed by formation of polyethoxylated phenol (H2O2/DBD) and addition of OH center dot radicals onto the aromatic ring (Fe2+/DBD). The final degradation products did not cause any significant toxic effects to Vibrio fischeri or Artemia salina.

A large number of producers offer a wide choice of various types of industrial cooling towers. Usually, a proper choice of pre-fabricated cooling tower satisfies end-user needs. However, if there are specific end-user requirements, it is necessary to design cooling tower according to those requirements. For the adhesive factory located in southern region of Serbia, 350 kW mechanical draught wet cooling tower was designed and built. Dimensioning of the. cooling tower was done according to parameters of the ambient air, higher than the standard recommendations given in the literature. In this paper, the reasons for deviation from recommendations are given. The analysis of the cooling tower operation based on real meteorological parameters for 2015 is also shown in this paper. According to this analysis, cooling tower provides required water temperature in any season, and gives opportunity for energy savings in winter, with opportunity for heat capacity enlargement if production capacity is raised as it is planned in the factory.

Microwave-hydrothermal method was used for the synthesis of TiO2 and TiO2 doped with zirconium. The method was fast and simple and adsorbents were used for removal of As(III) and As(V) from aqueous solutions. The adsorbents were characterized by BET surface area measurements and powder XRD. Experiments showed that TiO2 doped with 10% of Zr using the microwave-hydrothermal method have greater specific surface area and total pore volume in comparison with TiO2 synthesized using the same method. Better removal with doped adsorbent was obtained for both, As(III) and As(V). Further experiments were carried out with Zr doped TiO2 sorbent in order to examine kinetic of adsorption, influence of pH and effect of common anions present in natural waters.

Pharmaceutical compounds have been detected frequently in surface and ground water. Advanced Oxidation Processes (AOPs) were reported as very efficient for removal of various organic compounds. Nevertheless, due to incomplete degradation, toxic intermediates can induce more severe effects than the parent compound. Therefore, toxicity studies are necessary for the evaluation of possible uses of AOPs. In this study the effectiveness and capacity for environmental application of three different AOPs were estimated. They were applied and evaluated for removal of ibuprofen from water solutions. Therefore, two treatments were performed in a non-thermal plasma reactor with dielectric barrier discharge with and without a homogenous catalyst (Fe2+). The third treatment was the Fenton reaction. The degradation rate of ibuprofen was measured by HPLC-DAD and the main degradation products were identified using LC-MS TOF. Twelve degradation products were identified, and there were differences according to the various treatments applied. Toxicity effects were determined with two bioassays: Vibrio fischeri and Artemia salina. The efficiency of AOPs was demonstrated for all treatments, where after 15 min degradation percentage was over 80% accompanied by opening of the aromatic ring. In the treatment with homogenous catalyst degradation reached 99%. V. fischeri toxicity test has shown greater sensitivity to ibuprofen solution after the Fenton treatment in comparison to A. salina. (C) 2014 Elsevier B.V. All rights reserved.

Termoelektrane na fosilna goriva, pre svega ugalj, emituju velike količine ugljen dioksida, koji se smatra glavnim uzročnikom fenomena globalnog zagrevanja. Smanjenje emisije CO2 u energetskom sektoru je postalo jedan od osnovnih prioriteta svih nacionalnih vlada. Sa druge strane, globalno zagrevanje direktno utiče na proizvodnju energije. Ovaj uticaj se pre svega ogleda u mogućnosti odvođenja otpadne toplote, neophodnog za rad postrojenja. U doglednoj budućnosti efikasnost rada postojećih termoenergetskih postrojenja opadati, ukoliko se ne ulože dodatni napori kako bi se unapredio njihov rad, posebno imajući u vidu optimizaciju rada kondenzacionog dela postrojenja, a ovo opet vodi povećanoj emisiji CO2. Predviđeni porast potrošnje energije dodatno podvlači ovaj problem.U radu je dat pregled današnjih metoda za smanjenje emisije CO2 u atmosferu, ali je osnovni cilj rada da ukaže na mogućnosti povećanja energetske efikasnosti postojećih postrojenja, uz relativno mala ekonomska ulaganja, čime bi se smanjili i ekološki problemi. Prikazan je uticaj porasta temperature rashladne vode i vazduha na energetsku efikasnost termoelektrana u Srbiji sa protočnim i povratnim sistemom hlađenja. Rezultati su dobijeni na osnovu originalnih matematičkih modela i numeričkih simulacija, koje su autori predstavili u drugim radovima. Dobijeni rezultati mogu biti od koristi kako pri revitalizaciji postojećih, tako i pri projektovanju novih termoenergetskih kapaciteta., Coal-fired power plants emit large amounts of CO2, which constitutes one of the largest causes of global warming. Reducing CO2 emissions in the energy sector has become a top priority for national governments. On the other hand, fossil energy production is also affected by air and water temperatures. Local weather conditions affect the capacity of cooling towers and natural water bodies to transfer waste heat from steam condensers to the atmosphere. Without technology-based improvements in cooling system efficiency, the steam-cycle energy efficiency would decrease. This again leads to increased consumption of fossil fuels and thus increasing emissions of CO2. Increasing in global energy demand aggravates this issue. In this paper, the overview of currently actual methods for CO2 reduction is given. The main objective, however, is to find a cost-effective solution for increasing the energy efficiency of existing plants in Serbia. The overview of cooling water temperature increase impact on the energy efficiency in Serbian power plants is given, based on meteorological data and numerical simulation. This study is done for both, power plants with once-through and with closed cycle cooling system. Obtained results could be used as useful guidelines in design of the new power plants and also in improving existing power plants performances.

Primenjena hemija / Applied Chemistry, Degradacija triketonskih herbicida, mezotriona i sulkotriona, ispitana je pomoću sledećih unapreĎenih oksidacionih procesa (eng. Advanced Oxidation Processes, AOP): Fentonov reagens, fotokataliza, ozonizacija, plazma tretman, elektrohemijska degradacija.U prvom delu rada optimizovane su HPLC metode za kvantifikaciju triketonskih herbicida, tj. za praćenje efikasnosti degradacije i HPLC-MS metode za identifikaciju degradacionih proizvoda. Efikasnost mineralizacije pesticida je odreĎena preko HPK (hemijske potrošnje kiseonika) i TOC (totalnog organskog ugljenika) vrednosti. Identifikovano je ukupno trinaest degradacionih proizvoda kod oba pesticida, sedam aromatičnih proizvoda i šest alifatičnih karboksilnih dikiselina.Ispitana je degradacija mezotriona i sulkotriona Fentonovim reagensom (optimizovana koncentracija jona Fe2+), fotokatalizom, ozonizacijom i DBD reaktorom. Nakon svake degradacije su identifikovani glavni proizvodi degradacije i odreĎene HPK vrednosti za oba pesticida.U daljem radu je ispitana je mogućnost primene homogenih katalizatora za poboljšanje efikasnosti degradacije mezotriona u DBD reaktoru. Ispitana su četiri katalitička sistema i optimizovane koncentracije katalizatora i specifične gustine energije kako bi se dobila najveća efikasnost degradacije i mineralizacije. Za optimalne koncentracije katalizatora u svakom katalitičkom sistemu su idenfikovani degradacioni proizvodi i odreĎene TOC vrednosti. Efikasnost degradacije mezotriona u katalitičkim sistemima je bila: (SED 124 kJ/L): 5 ppm Fe2+/DBD > 10 mM H2O2/DBD > 1 ppm Mn2+/DBD > 5 ppm Co2+/DBD > DBD bez katalizatora. Efikasnost mineralizacije je bila: 10 mM H2O2 (71%) > 5 ppm Fe2+ (61%) > 5 ppm Co2+ (38%) > DBD bez katalizatora (34%) > 1 ppm Mn2+ (28%).Nakon toga je ispitana elektrohemijska degradacija mezotriona i sulkotriona u dvoelektrodnoj, nepodeljenoj ćeliji, sa natrijum-sulfatom kao osnovnim elektrolitom. Kod elektrohemijske degradacije su optimizovani različiti parametri: elektrodni m, Degradation of triketone herbicides, mesotrione and sulcotrione, was investigated using the following advanced oxidation processes (AOP): Fenton's reagent, photocatalysis, ozonation, plasma treatment and electrochemical degradation.In the first part of the work were optimized HPLC methods for the quantification of triketone herbicides and monitoring the effectiveness of degradation, while HPLC-MS methods were optimized for the identification of the degradation products. Mineralization efficiency was determined via COD (chemical oxygen demand) and TOC (total organic carbon) value. Thirteen degradation products were identified for both pesticides, including seven aromatic compounds and six aliphatic carboxylic diacids.Degradation of mesotrione and sulcotrione were investigated using Fenton's reagent (optimized concentration of Fe2+ ions), photocatalysis, ozonation and DBD reactor. Major degradation products and COD values were identified for both pesticides after each degradation procedure.In the further experiments was investigated possibility of application of homogeneous catalysts for improval of the mesotrione degradation efficiency in the DBD reactor. Four catalytic systems were tested and catalyst concentration and specific energy density (SED) were optimized in order to obtain the greatest effectiveness of degradation and mineralization. Degradation products and TOC values was determined for optimal concentration of the catalyst in each catalytic system. Mesotrione degradation efficiency in DBD catalytic systems was in order: (for SED 124 kJ / L): 5 ppm Fe2+/DBD > 10 mM H2O2/DBD > 1 ppm Mn2+/DBD > 5 ppm Co2+/DBD > DBD without catalyst. Mineralization efficiency was: 10 mM H2O2 (71%) > 5 ppm Fe2+ (61%) > 5 ppm Co2+ (38%) > DBD without catalyst (34%) > 1 ppm Mn2+ (28%).Electrochemical degradation of mesotrione and sulcotrione was studied in two-electrode undivided cell with sodium sulfate as supporting electrolyte. Different parameters were optimized: electrode m

The application of various electrodes for in situ degradation of Reactive Yellow 125 (RY125) and Reactive Green 15 (RG15) dyes, as well as ecotoxicity screening test of their degradation products were studied in this paper. The degradation process was performed in a two-electrode cylindrical cell, with Fisher platinum electrode as anode and Pd, Zr, or C electrodes as cathode; in 0.1 M Na2SO4 as supporting electrolyte. The optimal conditions (voltage and pH value) for degradation were determined in a platinum-palladium (Pt-Pd) model system for 200 mg/L of both reactive dyes. Then the electrolysis with other electrodes was conducted under the same conditions. Decolorization was monitored spectrofotometrically (UV-Vis) and the degradation efficiency was confirmed by HPLC technique with a DAD detector. Differences in degradation efficiency were observed between these three electrochemical systems (Pt-Pd, Pt-Zr, and Pt-C). The Pt-Pd system was the most efficient for the degradation of both reactive dyes. Achieved decolorization percentage for RG15 and RY125 were 98% and 97%, respectively. The ecotoxicity assessment of degradation products was performed using Anemia sauna. Toxicity data were compared by Kruskal-Wallis one-way analysis and pair-wise group comparisons with Mann-Whitney U tests. Statistically significant differences (p lt 0.05) in mortality (%) for Pt-Pd and Pt-Zr systems were determined between treated and untreated dye solutions of RG15. System Pt-C had no detectable significance in treatment of solutions of both dyes.

Electrochemical treatment is a new trend for the purification of textile industry wastewater which containing azo dyes. In this paper the electrochemical treatment was used for decolorization of azo dye Reactive Blue 52. The efficiency of decolorization was compared for different electrochemical systems which were all equipped with Fisher platinum electrode as anode and a different cathode (Zr, Pd, C) in sodium sulfate as supporting electrolyte. In order to find optimal conditions the influence of various voltage and pH values of initial dye solution was studied. Decolorization rate was monitored by spectrophotometer while degradation products were identified by high performance liquid chromatography-diode array detector (HPLC-DAD). Results of HPLC analysis confirmed presence of various degradation products in electrochemical systems, which indicated different mechanism of degradation. This was also confirmed by Ek-t curve. In terms of power consumption the most cost effective system was with the graphite cathode (C/Pt).

Fe-doped TiO2 photocatalysts with different contents of Fe (0.5, 1.6, 3.4 and 6.4 %) were synthesized by a microwave-hydrothermal method and characterized by X-ray diffraction analysis, N-2 physisorption at 77 K and UV-Vis spectrometry. The characterization showed that the Fe ions were highly dispersed in the TiO2 lattice. It was found that all the synthesized catalysts had a mesoporous structure and that Fe-doping increased the BET surface area. The UV-Vis study showed that the absorption spectra were shifted to longer wavelengths (red shift) with increasing dopant concentration. The photocatalytic activity of the samples was evaluated by the decolorization of the textile dye Reactive Blue 52 (RB) in aqueous solutions under sun-like radiation in the presence of H2O2 (a heterogeneous photo-Fenton process). The photocatalyst with 3.4 % Fe was found to be the most efficient in the presence of H2O2. The effect of the initial pH of the dye solution was assessed and dissolution of iron ions was studied as a function of pH value. It was concluded that decolorization was more favorable in acidic pH, and that at pH values >4, the release of Fe ions into the solution was negligible. Photocatalytic degradation of 4-chlorophenol (4-CP) was investigated under the optimal conditions and it was shown that the catalyst was capable of degrading colorless pollutants.

In this study the effect of different homogenous catalysts and their dosage on mesotrione degradation in water falling film dielectric barrier discharge (DBD) reactor was investigated. Four catalytic systems Mn2+ /DBD, Co2+/DBD, Fe2+/DBD and H2O2/DBD were examined. In order to find optimal conditions various concentrations of catalysts and specific energy density (SED) values were tested in each system. Mesotrione degradation efficiency was determined by HPLC-DAD and mineralization efficiency by TOC value. Degradation products were identified by UHPLC-Orbitrap-MS and compared after finding out the optimal concentration for each catalytic system. All studied catalytic systems have proved to be successful in improving mesotrione removal, but the highest improvement in degradation efficiency was obtained with catalytic system 5 ppm Fe2+/DBD (by 50% for SED 124 kJ/L) and 10 mM H2O2/DBD for improving mineralization efficiency (by 45% for SED 310 kJ/L). Nine degradation products were identified in catalytic DBD treatments. Main degradation products were: glutaric acid, 2-nitro-4-methylsulfonylbenzaldehyde and 2-nitro-4-methylsulfonylbenzoic acid. H2O2/DBD gave significantly different degradation products than other catalytic systems. Dominant degradation products in other systems were not identified in system with hydrogen peroxide, which supported the fact that the highest mineralization efficiency was achieved with peroxide catalytic system. Global toxicity of samples after degradation in each system was determined using Artemia sauna and they could be considered as "non toxic".

Degradation of two triketone herbicides, mesotrione and sulcotrione, was studied using four different advanced oxidation processes (AOPs): ozonization, dielectric barrier discharge (DBD reactor), photocatalysis and Fenton reagent, in order to find differences in mechanism of degradation. Degradation products were identified by high performance liquid chromatography (HPLC-DAD) and UHPLC-Orbitrap-MS analyses. A simple mechanism of degradation for different AOP was proposed. Thirteen products were identified during all degradations for both pesticides. It was assumed that the oxidation mechanisms in the all four technologies were not based only on the production and use of the hydroxyl radical, but they also included other kinds of oxidation mechanisms specific for each technology. Similarity was observed between degradation mechanism of ozonation and DBD. The greatest difference in the products was found in Fenton degradation which included the opening of benzene ring. When degraded with same AOP pesticides gave at the end of treatment the same products. Global toxicity and COD value of samples was determined after all degradations. Real water sample was used to study influence of organic matter on pesticide degradation. These results could lead to accurate estimates of the overall effects of triketone herbicides on environmental ecosystems and also contributed to the development of improved removal processes.