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EN
A significant amount of hazardous compounds has leaked into the environment due to the widespread usage of organic dyes, and it is essential that these dangerous contaminants be removed in a sustainable way. This study used varying amounts of H2O2 (0, 0.5, 1.5, 3, and 5) mM/L to extract the dye from the aqueous solution. Furthermore, concentrations of 0.4, 1, 1.7, and 2.3 mM/L of Fe+2 as FeSO4•7H2O were also utilized. Batch Advanced Oxidation Process (AOP) was carried out under various working conditions, including: contact time (5–60 min), mixing speed (100–300 rpm), and UV light intensity (0–40 W). Utilizing experimental data, the AOP efficiency of Dispersed Red 17 Dye was calculated. Genetic Cascade-forward Neural Network (GCNN) was employed as a machine-learning tool to forecast the oxidation efficiency and the amount of dye that would be removed from the aqueous solution, specifically Dispersed Red 17. When compared to experimental data, the best model had an R2 correlation value of 0.955. The findings of the importance analysis showed that the studied parameters affected the discoloration efficiency with order of: H2O2, UV, Fe+2, mixing speed, and contact time. The obtained results demonstrated the effectiveness of GCNN as a novel approach in forecasting the AOP efficiency of Dispersed Red 17 Dye.
EN
Experimental activities carried out in laboratories usually produce complex wastewater. Due to practicum and research activities in educational laboratories, the wastewater generating from these laboratories contains organic and inorganic compounds which are dangerous for the environment if disposed of without prior treatment. Apart from high chemical oxygen demand (COD) and biological oxygen demand (BOD) values, laboratory wastewater also often contains heavy metals such as zinc (Zn), copper (Cu), chromium (Cr), lead (Pb), and iron (Fe) which are included in the hazardous waste category and can pollute the ground water. Therefore, this wastewater must be treated properly. The objective of this study is to reduce the pollutant load contained in laboratory wastewater by using combination methods of advanced oxidation processes (AOPs), and chemical-physical treatment namely coagulation and adsorption processes. The photo-Fenton process was selected as one of AOPs applied in this treatment. The effect of molar ratio variation and irradiation time in the Photo-Fenton process on the pollution load in the form of pH, COD, BOD, TSS, and heavy metals of Zn, Cu, Cr, Pb, and Fe was studied in this research. The results of the analysis of untreated laboratory wastewater samples showed that laboratory wastewater did not meet the wastewater quality standards regulated by the government of Republic of Indonesia. In this study, laboratory wastewater was treated using the pretreatment method of coagulation with alum and adsorption with activated carbon. The best results in this study were obtained in the final adsorption results after treatment with the photo-Fenton method using a molar ratio of 1: 300 for 60 minutes in which several parameters such as pH, Zn, Cu, Pb, and Fe had met environmental quality standards with the value of each parameter of 7; 0.01 mg/L; 2.9 mg/L; 0.03 mg/L; and 3.15 mg/L respectively. Meanwhile, the percentage reduction of COD, BOD, and TSS parameters was 87.49%, 87.02%, and 72.45% respectively.
EN
Technology advancement improves the quality of life, however, it might also introduce new pollutants to the ecosystem, which needs to deal with for the goal of a sustainable ecosystem. Municipal and industrial wastewater has always been important in improving the quality of life while maintaining the sustainability of our planet simultaneously. The diversity of pollutants in wastewater requires more advanced and demanding treatment processes. The ozonation, as a crucial part of the advanced oxidation processes, is a superior oxidation method compared to traditional oxidation methods. After the recognition of ozone as GRAS (generally recognized as safe), its applications have diversified and is used currently for microbial inactivation, degradation of recalcitrant organic compounds, removal of a diverse range of micropollutants, solubilization and reduction of sludge, and removal of color and odor components in wastewaters treatment processes. However, some considerable challenges still exist towards its universal application, such as high ozone generation costs, diversity of pollutants, and formation of ozonation by-products, which still require further studies. The main theme of this review paper is the transformation of traditional oxidation methods into advanced oxidation processes and the role of ozonation in this regard, including its applications, by-products, and its comparison with the traditional oxidation methods and advanced oxidation processes.
EN
Produced water is one of the most dangerous types of pollution for the environment, specifically the soil, since it is full of oil, suspended particulates, dissolved compounds, and various other pollutants. This research describes the advanced oxidation process (AOPs) that were studied to purge the generated water from the Al Khabaz oilfield located in (Northern Iraq – Kirkuk governorate) of any oil content using two photocatalytic homogeneous and heterogeneous processes in the batch system under optimal conditions: homogeneous processes, including Photo-Fenton (hydrogen peroxide, ferrous sulfates, and ultraviolet light), and Fenton process (hydrogen peroxide, and ferrous sulfates), and Direct-Photolysis (ultraviolet only) were used studied the effects of hydrogen peroxide (H2O2) & ferrous sulfate (Fe+2), doses, irradiation time, pH Value, and intensity of UV to the oil removal efficiency. This work investigated the maximum efficiency in Photo Fenton = 85.68%, in Fenton = 75.01%, and in direct UV photolysis = 56.64%. The heterogeneous photocatalytic process (TiO2/UV) studied the effect of titanium dioxide (TiO2) nanoparticles doses and UV intensity. The results show that the optimal efficiency achieved was 60.95%. X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier Transforms Infrared Spectroscopy (FT-IR) were used to look into the characteristics of the catalyst titanium dioxide nanoparticles. TiO2 NPs seemed to be spherical in the SEM test, and their FT-IR analysis absorption values ranged from 424.77 to 3403.71 cm-1. Their sizes varied between 31.57 and 38.40 nm, and XRD revealed details regarding their chemical composition.
PL
Przedstawiono wyniki badań nad możliwością zastosowania procesów zaawansowanego utleniania materii organicznej w ściekach do form bardziej biodegradowalnych. Ścieki poddano ozonowaniu, naświetlaniu promieniami UV lampą niskociśnieniową (UV₂₅₄) i średniociśnieniową (UVśr), utlenianiu H₂O₂ oraz kombinacji tych procesów: O₃/UVśr, O₃/UV₂₅₄, O₃/H₂O₂, UVśr/H₂O₂, UVśr/ O₃/H₂O₂, UV₂₅₄/H₂O₂ i UV₂₅₄/ O₃/H₂O₂. Oznaczono takie parametry ścieków, jak ChZT, BZT₅, barwa i odczyn. Najlepszy efekt zwiększenia biodegradowalności materii organicznej (najmniejszy stosunek ChZT/BZT) w ściekach uzyskano po ozonowaniu i procesie UV₂₅₄/O₃/H₂O₂.
EN
The car wash wastewater was treated with O₃, H₂O₂ and/or irradn. with low- and medium-pressure UV lamp for 0–150 min. COD, BOD, color and pH were tested in raw and treated sewage. The best effect of increasing the biodegradability of org. matter (the lowest COD/BOD ratio) in the wastewater was obtained after O₃ and the UV₂₅₄/O₃/H₂O₂ processes. The best overall effect of waste water treatment in terms of COD and color removal was obsd. after ozonation.
EN
Water pollution and the lack of access to clean water are general global problems that result from the expansion of industrial and agricultural activities. Petroleum refinery wastewaters are considered as a major challenge to the environment and their treatment is mandatory. The present work investigated the removal of chemical oxygen demand (COD) from petroleum refinery effluents generated from the Al-Dewaniya petroleum refinery plant located in Iraq by utilizing a novel graphite–graphite electro-Fenton (EF) system. The electrochemical reactor was a tubular type with a cylindrical cathode made from porous graphite and concentric porous graphite rode acts as an anode. By adopting the response surface methodology (RSM), the impacts of different operating variables on the COD removal were investigated. The optimal conditions were a current density of 25 mA/cm2, FeSO4 concentration of 1.4 mM, and electrolysis time of 90 minutes, which resulted in the COD removal efficiency (RE%) of 99% at a specific energy consumption (SEC) of 10.34 kWh/kg COD. The results indicated that both current density and concentration of FeSO4 have a major impact on the elimination of COD, while time has a minor effect. The adequacy of the model equation was demonstrated by its high R2 value (0.987). The present work demonstrated that the graphite–graphite EF system could be considered as an effective approach for removing of COD from petroleum refinery wastewaters.
EN
This paper aims to investigate the ability of photo-Fenton technology to remove Reactive Red dye (RR-dye) from wastewater using batch and continuous operating modes. The batch mode of photo-Fenton removal of organic content was conducted under the influence of solution pH (3–10), hydrogen peroxide (25–100 ppm), irradiation time (20–90 min), ferrous sulphate (5–20 ppm), and temperature (25–60 °C). For comparison, the continuous treatment was conducted under the influence of the flow rate of the contaminated solution (10, 20, 30, 40, and 50 mL/min). The results revealed that the treatability of the batch mode was more effective compared to the continuous mode. In the batch process, the organic contaminant was completely removed compared to that of 82% obtained when the continuous system was performed. The optimization process showed that the optimal values of the operating variables in the case of the batch removal of RR-dye were 3, 78 ppm, 90 min, 20 ppm, and 60 °C for pH, hydrogen peroxide, irradiation time, ferrous sulphate, and temperature, respectively. Moreover, the reversion F-value was 21.69, the probability P value was less than 0.001, and the correlation coefficient was (R2 = 0.9455), which illustrative the significance of the model obtained for the batch process.
EN
Synthetic dyes are persistent pollutants with poor biodegradability. The present study is about the degradation of direct Congo red dye in aqueous media using the Co-60 gamma radiation source. The experimental conditions such as gamma-ray absorbed doses, amount of oxidant (H2O2) and pH conditions were evaluated. The lambda max of dye solution was noted as 498 nm, and then, decrease in absorbance and reduction in chemical oxygen demand (COD) were examined. The complete colour removal of dye was observed at 5 kGy, while a signifi cant COD removal was observed at 15 kGy gamma-ray absorbed dose in conjunction with oxidant for 50 mg/L concentration. It was found that pH has no influence on degradation efficiency. A possible degradation pathway was proposed. The radiolytic end products were monitored by Fourier transform infrared (FTIR) and gas chromatography coupled with mass spectrometry (GC-MS) to explore the degradation mechanism. It was imperative to study the oxidative degradation pathway to provide directions for potential applicability of advanced oxidation process (AOP) in industrial wastewater treatment.
EN
The study presented the results of the examinations obtained during treatment of dairy wastewater in a membrane photoreactor where photocatalysis was sequentially combined with low-pressure membrane process. The aim of the study was to determine the effectiveness of degradation of the contaminants contained in such wastewater during photocatalysis and in the arrangement that combined photocatalysis with ultrafiltration. Several experiments were performed in order to determine the most beneficial conditions of the photocatalysis process, e.g. the dose of the photocatalysts used (TiO2 and ZnO), duration of the process and pH of wastewater subjected to oxidation. The dose of titanium dioxide was changed from 1 to 40 g/dm3, whereas the content of zinc oxide ranged from 1 to 6 g/dm3. The results obtained in the study showed that the extension of the irradiation time to over 30 minutes (TiO2) and over 45 minutes (ZnO) during photocatalysis does not lead to increased removal of contaminants from the dairy wastewater. It was also demonstrated that the increase in the doses of both photocatalysts does not lead to the increase in the efficiency of their treatment. In the case of treatment of dairy wastwater with TiO2, the photocatalysis occurred most effectively for its dose of 10 g/dm3. Removal rates for COD, TOC and total nitrogen were 58% (1670 mg/dm3), 62% (450 mg/dm3) and 56% (128 mg/dm3), respectively. Replacing titanium dioxide with zinc oxide (ZnO – 2 g/dm3) in the photocatalysis process allowed for obtaining higher degrees of removal of contaminants determined as COD, TOC and total nitrogen to the level of 77.8% (870 mg/dm3), 62% (445 mg/dm3) and 52% (139 mg/dm3), respectively. Since both photocatalysts were supplied to the photoreactor in the form of a suspension, the membrane in the next reactor represented an efficient barrier for their particles. It was observed that higher volumetric stream of the permeate was obtained during the process of low-pressure membrane filtration of sewage initially treated in the process of photocatalysis with titanium dioxide (4.6·10-5 m3/m2·s – TiO2 and 4.1·10-5m3/m2·s – ZnO). It was found that the ultrafiltration process in the case of the feed material with TiO2 led to the reduction in COD, TOC and total nitrogen by 78% (370 mg/dm3), 72% (126 mg/dm3) and 40% (80 mg/dm3). Slightly better quality of permeate was obtained when the feed material contained ZnO powder. Degree of retention of the contaminants COD, TOC and total nitrogen were 68% (280 mg/dm3), 66% (143 mg/dm3) and 42% (76 mg/dm3), respectively.
PL
W pracy zaprezentowano wyniki badań jakie otrzymano podczas oczyszczania ścieków mleczarskich w fotoreaktorze membranowy w którym sekwencyjnie skojarzono procesy fotokatalizę z niskociśnieniowym procesem membranowymi. Celem badań było określenie skuteczności degradacji zanieczyszczeń znajdujących się w tego rodzaju wodach odpadowych w samodzielnie prowadzonym procesie fotokatalizy jak również w układzie kojarzącym go z procesem ultrafiltracji. Przeprowadzono szereg eksperymentów w celu ustalenia najkorzystniejszych warunków prowadzenia procesu fotokatalizy tj. dawka zastosowanych fotokatalizatorów (TiO2 i ZnO), czas prowadzenia procesu oraz wartość pH ścieków poddawanych utlenianiu. Dawkę ditlenku tytanu zmieniano w zakresie od 1 do 40 g/dm3 a tlenku cynku od 1 do 6 g/dm3. Na podstawie uzyskanych wyników badań stwierdzono, że wydłużanie czasu naświetlania powyżej 30 minut (TiO2) oraz powyżej 45 min (ZnO) w procesie fotokatalizy nie wpływa na zwiększanie usunięcia zanieczyszczeń z oczyszczanych ścieków mleczarskich. Wykazano również, że zwiększanie stosowanych dawek obu fotokatalizatorów nie skutkuje wzrostu efektywności ich oczyszczania. W przypadku oczyszczania ścieków mleczarskich z TiO2 proces fotokatalizy przebiegał najkorzystniej jego dawce wynoszącej 10 g/dm3. Stopień usunięcia ChZT, OWO i azotu ogólnego wynosił odpowiednio 58% (1670 mg/dm3), 62% (450 mg/dm3) i 56% (128 mg/dm3). Zastąpienie ditlenku tytanu tlenkiem cynku (ZnO – 2g/dm3) w procesie fotokatalizy pozwoliło na uzyskanie wyższych stopni usunięcia zanieczyszczeń oznaczanych jako ChZT, OWO i azotu ogólnego odpowiednio do poziomu 77.8% (870 mg/dm3), 62% (445 mg/dm3) i 52% (139 mg/dm3). Z uwagi na fakt, że oba dawkowano do fotoreaktora w formie zawiesiny to znajdująca się w kolejnym reaktorze membrana była skuteczną barierę dla ich cząstek. Zaobserwowano, że wyższy objętościowy strumień permeatu uzyskano w trakcie prowadzenia procesu niskociśnieniowej filtracji membranowej ścieków wstępnie podczyszczonych w procesie fotokatalizy z ditlenkiem tytanu (4,6·10-5 m3/m2·s – TiO2 i 4,1·10-5 m3/m2·s – ZnO). Stwierdzono że wykorzystany proces ultrafiltracji w przypadku nadawy z TiO2 przyczynił się do obniżenia wartości wskaźników ChZT, OWO i azotu ogólnego odpowiednio o 78% (370 mg/dm3), 72 % (126 mg/dm3) i 40% (80 mg/dm3). Nieznacznie lepszej jakości permeat otrzymano, gdy nadawa zawierała proszek ZnO. Stopień retencji zanieczyszczeń ChZT, OWO i azotu ogólnego wynosił odpowiednio 68% (280 mg/dm3), 66 % (143 mg/dm3) i 42% (76 mg/dm3).
10
EN
The paper presents the possibility of using the ozonation process in landfill leachate pretreatment. The study was conducted in three stages. In the first stage, the landfill leachate was subjected only to the ozone, with the dose varying from 10 mg/dm3 to 40 mg/dm3. As part of this stage of research, the effect of changes in the pH of wastewater undergoing the process of ozonation on the efficiency of TOC removal was examined. For all the tested pH values (pH = 3.5, pH = 7 pH = 8.5 pH = 10), the TOC removal rate constant (kRowo) during ozonization was determined. In the second stage of the study, the ozonation process was facilitated by UV radiation. Additionally in this stage, the rate of generation of OH• radicals was accelerated by the addition of hydrogen peroxide to the reactor. The COD: H2O2 ratio by weight was 1:2.5, 1:5 and 1:10 and 1:20. In the last stage of the study, we attempted to assist the ozonation process using ultrasonic field. The employed vibration amplitude amounted to 25μm and sonication time equalled 300 seconds. It was found that the ozonation process is the most effective at alkaline pH (8.5). The TOC removal efficiency was 37% (346 mg/dm3) after 60 minutes of ozonation. The best results of pollutants oxidation measured as COD and TOC removal were observed when the dose of ozone was 20 mg/dm3. The combination of sonication and ozonation has resulted in a reduction of COD and TOC values by 370 mg/dm3 and 126 mg/3, respectively, in comparison to the ozonation process alone. It was found that the most effective process in landfill leachate treatment is the combination of ozonation with hydrogen peroxide addition (COD:H2O2=1:10). The COD, TOC and BOD values were 65%, 62% and 36% lower, respectively, in comparison to ozonation process conducted alone.
EN
The paper presents the research results on the possibility of the integration of advanced oxidation process (AOP) involving Fenton reaction with nanofiltration (NF) for dairy effluent treatment. It has been found that Fenton oxidation reduces organic compounds, total phosphorus and total nitrogen. However, NF enables high ions retention derived from both effluent and Fenton oxidation components. As a result, it was possible to obtain water, which, without any harmful effects, could be discharged into environment. This water also fulfilled most of the requirements to be reused in dairy industrial plant.
EN
The possibility of removing organic compounds from wastewater originating from the photochemical production of printed circuit boards by use of waste acidification and disposal of precipitated photopolymer in the first stage and the UV-Fenton method in a second stage has been presented. To optimize the process of advanced oxidation, the RSM (Response Surface Methodology) for three independent factors was applied, i.e. pH, the concentration of Fe(II) and H2O2 concentration. The use of optimized values of individual parameters in the process of wastewater treatment caused a decrease in the concentration of the organic compounds denoted as COD by approx. 87% in the first stage and approx. 98% after application of both processes. Precipitation and the decomposition of organic compounds was associated with a decrease of wastewater COD to below 100 mg O2/L whereas the initial value was 5550 mg O2/L. Decomposition of organic compounds and verification of the developed model of photopolymers removal was also carried out with use of alternative H2O2 sources i.e. CaO2, MgO2, and Na2CO3·1,5H2O2.
PL
Przedstawiono możliwość usuwania związków organicznych ze ścieków pochodzących z fotochemicznej produkcji obwodów drukowanych przez zastosowanie w pierwszym etapie zakwaszania ścieków i usuwaniem wytrąconego fotopolimeru, a w drugim etapie metody UV-Fentona. Do optymalizacji procesu pogłębionego utleniania zastosowano metodę powierzchni odpowiedzi dla trzech czynników niezależnych, tj.: pH, stężenia Fe(II) oraz stężenia H2O2. Zastosowanie zoptymalizowanych wartości poszczególnych parametrów w procesie oczyszczania ścieków spowodowało zmniejszenie stężania związków organicznych oznaczanych jako COD o ok. 87% w pierwszym etapie oraz ok. 98% po zastosowaniu obu procesów. Wytrącanie oraz rozkład związków organicznych związane były ze zmniejszeniem się COD ścieków do poniżej 100 mg O2/L, przy początkowej wartości wynoszącej 5550 mg O2/L. Rozkład związków organicznych oraz weryfi kację opracowanego modelu procesu usuwania fotopolimerów przeprowadzono także z zastosowaniem alternatywnych źródeł H2O2, tj.: CaO2, MgO2, i Na2CO3·1,5H2O2.
EN
Surfactants after their use are discharged into aquatic ecosystems. These compounds may be harmful to fauna and flora in surface waters or can be toxic for microorganisms of the activated sludge or biofilm in WWTP. In order to determine effectiveness of different advanced oxidation processes on the degradation of surfactants, in this study the degradation of anionic surfactants in aqueous solution using photolysis by 254 nm irradiation and by advanced oxidation process in a H2O2/UVC system was investigated. Two representatives of anionic surfactants, linear alkyl benzene sulphonate (LAS-R11-14) and ether carboxylic derivate (EC-R12-14E10) were tested. The influence of pH, initial surfactant concentration and dose of hydrogen peroxide on the degradation was also studied. Results show outstanding effectiveness of the H2O2/UVC system in the removal of surfactant from aqueous solutions.
PL
Surfaktanty, podobnie jak większość tego typu substancji chemicznych, po wykorzystaniu trafi ają do środowiska wodnego. Związki te mogą stwarzać zagrożenie dla fl ory i fauny zasiedlającej wody powierzchniowe, jak również mogą działać toksycznie na mikroorganizmy znajdujące się w osadzie czynnym w oczyszczalniach ścieków. W niniejszej pracy przedstawiono wyniki badań degradacji wybranych surfaktantów anionowych w środowisku wodnym przy zastosowaniu promieniowania UVC i zaawansowanego utleniania w układzie H2O2/UVC. Zbadano wpływ następujących parametrów reakcyjnych: odczyn środowiska reakcyjnego, początkowego stężenia obiektów badań i nadtlenku wodoru na szybkość degradacji surfaktantów. Uzyskane w toku prac badawczych wyniki potwierdzają wysoką skuteczność zaawansowanego utleniania w układzie H2O2/UVC w usuwaniu badanych surfaktantów ze środowiska wodnego, które jest procesem znacznie efektywniejszym w porównaniu do procesu fotolizy. Unauthenticated
EN
The paper presents presents the possibility of using the ozonation process in coke wastewater treatment. The wastewater produced during processing of coke was initially pre-treated mechanically in order to remove solid impurities, oils and tar substances. The raw wastewater was characterized by the phenolic odor, brown color and alkaline pH (pH 9.2). The COD value of raw wastewater was 8100 mg/dm3 and the value of BOD was very low (180 mg/dm3). A high concentration of total nitrogen (2420 mg/dm3) and TOC (2240 mg/dm3) was also noted. The study was conducted in three stages. In the first stage, coking wastewater was treated only by ozone, the dose of which varied from 10 mg/dm3 to 40 mg/dm3. The effect of pH during ozonation process was determined on TOC removal efficiency. For all of the pH values (pH = 3.5, pH = 7, pH = 8.5 and pH = 11.5) the TOC removal rate constant was determined. In the second stage, the rate OH radicals generation was accelerated by the addition of hydrogen peroxide to the reactor. The ratio by weight of COD: H2O2 was 1:2.5, 1:5, 1:10 and 1:20. In the last stage of the study, we attempted to assist the ozonation process with ultrasonic field. The sonication time was 8 minutes and the amplitude was 61.5 μm. It was found that the ozonation process is the most effective at alkaline pH (8.5). The TOC removal efficiency was 34% (1470 mg/dm3) after 60 minutes of ozonation. The best results of oxidation of pollutants measured as COD and TOC removal were observed when the dose of ozone was 30 mg/dm3.The combination of sonication and ozonation has resulted in a reduction of COD and TOC values by 1000 mg/dm3 and 300 mg/dm3, respectively, in comparison to ozonation process alone. It was found that the most effective process in coke wastewater treatment is the combination of ozonation with hydrogen peroxide addition (COD:H2O2=1:10). The COD, TOC and BOD value were 54%, 35% and 20% lower, respectively, in comparison to ozonation process conducted alone.
EN
High organic matter content is a basic problem in food industry wastewaters. Typically, the amount and composition of the effluent varies considerably. In the article four groups of advanced processes and their combination of food industry wastewater treatment have been reviewed: electrochemical oxidation (EC), Fenton’s process, ozonation of water and photocatalytic processes. All advanced oxidation processes (AOP`s) are characterized by a common chemical feature: the capability of exploiting high reactivity of HO radicals in driving oxidation processes which are suitable for achieving decolonization and odour reduction, and the complete mineralization or increase of bioavailability of recalcitrant organic pollutants.
EN
The bleaching of greige linen woven fabric using ultraviolet irradiation on hydrogen peroxide impregnated samples was studied. The effect of a photoinitiator, sodium hydroxide, sodium peroxydisulphate for hydrogen peroxide, the irradiation time and distance between the fabric and ultraviolet light lamp on the samples’ whiteness, lightness, weight loss, moisture sorption and wettability properties was investigated. The UV/H2O2 bleaching process was optimised with the aid of Box-Behnken experimental design and three optimum recipes were achieved. As a result of the study, a novel bleaching process using ultraviolet irradiation and hydrogen peroxide for greige linen woven fabric was developed which saves on energy and time.
PL
Badano bielenie tkanin lnianych impregnowanych nadtlenkiem wodoru z zastosowaniem promieniowania ultrafioletowego. Badano wpływ fotoinicjatora, wodorotlenku sodu, nadsiarczanu sodu, nadtlenku wodoru, czasu naświetlania i odległości pomiędzy tkaniną a lampą UV na stopień bieli, jasność, utratę masy, sorpcję wilgoci i właściwości zwilżające. Proces bielenia UV/H2O2 zoptymalizowano przy pomocy metody Box-Behnkena. Uzyskano trzy optymalne receptury. W wyniku badań opracowano nowy proces bielenia tkanin lnianych, który pozwala na oszczędność energii i czasu.
PL
W pracy przedstawiono przegląd literatury odnośnie usuwania prekursorów ubocznych produktów utleniania i dezynfekcji wody. Zmniejszenie ilości zanieczyszczeń wywołanych obecnością substancji organicznych naturalnie występujących w wodach (NOM) oraz mikroorganizmów jest jednym z podstawowych celów uzdatniania. Obecność NOM ma bezpośredni wpływ m.in. na smak, zapach i barwę wody. Prowadzi do zwiększonego zapotrzebowania na koagulanty i dezynfektanty oraz podwyższonego zużycia chloru w sieci wodociągowej. Może to być przyczyną wtórnego zanieczyszczenia wody w sieci dystrybucyjnej. W ostatnich latach prowadzone są liczne badania mające na celu usuwanie ubocznych produktów utleniania/dezynfekcji wody. Nowe rozwiązania technologiczne polegają na zmianie warunków prowadzenia klasycznych procesów, wprowadzaniu nowego rodzaju koagulantów i reagentów chemicznych. Coraz więcej uwagi poświęca się procesom pogłębionego utleniania, dezynfekcji fizycznej, wymianie jonowej na selektywnych żywicach czy ciśnieniowym procesom membranowym. Zastosowanie promieniowania ultrafioletowego do dezynfekcji pozwala na uniknięcie postawania UPD lecz nie zabezpiecza wody w sieci wodociągowej przed wtórnym rozwojem mikroorganizmów.
EN
The paper presents a literature review for the disposal of oxidation and disinfection by-products of water. Reduction of the pollution amount caused by the presence of naturally occurring organic matter (NOM) in water and microorganisms is one of the fundamental objectives of treatment. The presence of NOM has a direct impact on the taste, smell and colour of water. It leads to an increased demand for coagulants and disinfectants and higher consumption of chlorine in the water supply system. It may be the reason of water secondary pollution in the distribution network. In recent years, numerous studies are conducted in order to remove by-products of the oxidation / disinfection. New technologies involve changes to the conditions for classical processes, the introduction of new types of coagulant and chemical reagents. Greater attention is devoted to advanced oxidation processes, physical disinfection, ion-exchange on selective resins or pressure-driven membrane processes. In the disinfection a better solution is to use ultraviolet radiation. The problem is, however, insufficient water supply protection against secondary microbiological growth.
EN
In the present study, ZnS nanoparticles were prepared using the mechanochemical method. The ZnS nanoparticles prepared were doped with different concentrations of manganese using metal acetate and manganese acetate by mechanochemical method. The as-prepared particles were characterized using X-ray diffraction (XRD) and transmission electron microscopy (TEM). The photocatalytic activity of the prepared nanoparticles samples, in the photocatalytic degradation of malachite green, had been investigated. The nanoparticles were photo induced, generating hole transfer for photocatalytic activity. The photodegradation of malachite green was observed at different pH (2-5) values, dye concentrations (10-100mg/L) and amount of ZnS nanoparticles (1-2.5 g/L). About 95% degradation of dye was observed on the addition of 2 g/L ZnS in 50 mg/L dye solution after 90 minutes illumination at 125 W. Degradation has been increased up to 99% using UV/nanoparticles/H2O2 (50 mL/L) combined process. The degradation efficiency was also compared using Mn doped ZnS nanoparticles (Zn1-x MnxS, where x = 0.01, 0.22 and 0.3). Maximum of 97% degradation was observed with 0.01% concentration of Mn. Kinetics study and performance of UV/ZnS, UV/ZnS/H2O2, UV/doped ZnS processes were evaluated to compare the efficiency of different processes.
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