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1

Modeling of Dispersed Red 17 Dye Removal from an Aqueous Solution Using Artificial Neural Network

Ibrahim Abdullah I., Asmel Nabel K., Alabdraba Waleed M. S., Al-Nima Raid R. O.

Journal of Ecological Engineering

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2024

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Vol. 25, nr 2

10--19

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.

2

Fabrication of heterojunction MnTiO3–TiO2-decorated carbon nanofibers via electrospinning as an effective multifunctional photocatalyst

Yousef Ayman

Materials Science Poland

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2022

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Vol. 40, No. 2

289--305

EN

In this paper, we successfully synthesized heterojunction manganese titanate/titanate nanoparticles (MnTiO3–TiO2 NPs)-decorated carbon nanofibers (CNFs) employing the electrospinning process. The morphology, crystallinity, and chemical composition of the MnTiO3–TiO2-decorated CNFs is characterized via SEM, FESEM, STEM, TEM EDX, and XRD techniques. The synthesized nanocomposite exhibits good performance for photodegradation of methylene blue (MB) dye and hydrolysis of ammonia–borane complex for hydrogen releasing experiment in a batch reactor under visible light. A mathematical model was developed to predict the photocatalytic activity of the produced nanocomposite with various parameters. The operational parameters include the effect of the initial concentration, catalyst dosage, light intensity, and reaction temperature, which are studied to validate the mathematical model. The reaction rate constant of MB photodegradation is found to be 0.0153 min−1 for an initial MB concentration of 5 mg·L−1 with a catalytic dosage of 200 mg·L−1 at a reaction temperature of 25°C under a light intensity of 25 W·m−2. Similarly, the H2 generation employing TiO2@CNFs and MnTiO3–TiO2@CNFs under visible light irradiation is observed to be 0.31 mol and 2.95 mol, respectively, corresponding to an exposure of 10 min. We also demonstrated that the yield of hydrogen employing MnTiO3–TiO2@CNFs under visible light increases to 2.95 mol compared with 1.51 mol in darkness. Finally, comparisons were made between the experimental and model-predicted values of the reaction rate constant and final concentrations. Theoretical and experimental data of photocatalytic activity are found to be in good agreement for MnTiO3–TiO2@CNFs.

3

Low-cost removal of basic red 9 using cow dung ash

Arya Raj Kumar, Meena Ghanshyam, Thapliyal Devyani, Barman Sanghamitra, Halder Gopinath, Shandilya Pooja

Chemical and Process Engineering

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2022

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Vol. 43, nr 2

229-–242

EN

In the present study, basic red 9 had been removed from synthetic waste water using animal waste. Cow dung ash had been prepared and characterized by scanning electron microscope. Morphology analysis shows very fine particles of less than 1 μm. The pH analysis study favours a pH of 8.5 for maximum dye removal. The removal of basic red 9 was very fast on cow dung ash. Percentage dye removal was 80.24% and 95.24 in 5 minutes and 90 minutes, respectively at initial dye concentration of 10 ppm.

4

Removal of reactive dyes from aqueous solutions using ultrafiltration membranes

Ahmed Arif Eftekhar, Majewska-Nowak Katarzyna, Grzegorzek Martyna

Environment Protection Engineering

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2021

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Vol. 47, nr 3

109--120

EN

The removal of five reactive dyes varying in molecular weight (Reactive Orange 16, Remazol Brilliant Blue R, Reactive Orange 20, Reactive Black 5, Reactive Red 120) was evaluated by using flat ultrafiltration membranes made of polyethersulfone (PES) and regenerated cellulose (C) characterized by various cut-off values (5, 10, and 30 kDa). The ultrafiltration process was performed in a dead-end mode under the transmembrane pressure range of 0.05–0.2 MPa. Dye concentration in model solutions was equal to 100 mg/dm3. The separation efficiency of all tested dyes was strongly dependent on the membrane type and the membrane cut-off, as well as on the applied pressure. Unexpectedly, the molecular weight of the tested reactive dyes had a minor impact on the dye removal effectiveness. The ultrafiltration membranes made of polyethersulfone and regenerated cellulose can be used in reactive dye removal on the condition that the membrane cut-off is not higher than 10 kDa. The PES and C membranes enable the separation of reactive dyes by 80–97%, and 45–89%, respectively.

5

Chemically modified excessive sludge as an adsorbent of dyes

Pieczykolan Barbara, Płonka Izabela, Zając Robert

Proceedings of ECOpole

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2020

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Vol. 14, No. 1

29--37

EN

In the municipal wastewater treatment technology, the biological method based on the activated sludge process is most commonly used. The activated sludge consists of small flocs, which mainly include bacteria. During the purification process, the growth of microorganisms and their multiplication occurs. Whereby it is necessary to discharge the excess sludge outside the technological system to maintain the concentration of the activated sludge in bioreactor at the appropriate level. Currently, the excess sludge is subjected to the stabilization process (usually biologically) and then it is directed to e.g. agricultural use as fertilizer. In recent years, research is conducted on the use of excessive sludge in the sorption process as a waste sorbent. During the studies, experiments on the use of a chemically modified excess sludge (as an sorbent) to remove two dyes from aqueous solutions (Acid Red 18 and Acid Green 16) were conducted. Excessive activated sludge was thickened, dried at 105 °C and ground to a grain size < 0.49 mm. The sludge was then chemically treated using Fenton's reagent. Next, the adsorption process was carried out. The effect of pH, the effect of reaction time and sorption isotherm was determined. Parameters of three models of isotherms were calculated: Freundlich, Langmuir and Dubinin-Radushkevich.

PL

W technologii oczyszczania ścieków komunalnych najczęściej stosowana jest metoda biologiczna wykorzystująca osad czynny. Osad czynny składa się z małych kłaczków, które głównie zawierają bakterie. Podczas procesu oczyszczania ma miejsce wzrost mikroorganizmów i ich namnażanie. W związku z tym konieczne jest odprowadzenie nadmiaru osadu poza układ technologiczny w celu utrzymania na odpowiednim poziomie stężenia osadu czynnego w bioreaktorze. Obecnie osad nadmierny poddawany jest procesowi stabilizacji (zwykle biologicznej), a następnie kierowany np. do wykorzystania rolniczego jako nawóz. W ostatnich latach prowadzone są badania nad możliwością wykorzystania osadu nadmiernego jako sorbentu odpadowego w procesie sorpcji. Podczas badań przeprowadzono eksperymenty z użyciem chemicznie modyfikowanego osadu nadmiernego (jako sorbentu) do usuwania dwóch barwników z roztworów wodnych (Acid Red 18 oraz Acid Green 16). Nadmierny osad czynny zagęszczono, wysuszono w 105 °C i zmielono do wielkości ziarna < 0,49 mm. Następnie osad poddano obróbce chemicznej z użyciem odczynnika Fentona, po czym przeprowadzono proces adsorpcji. Określono wpływ pH, czas reakcji i wyznaczono izotermę sorpcji. Ponadto obliczono parametry trzech modeli izoterm: Freundlicha, Langmuira i Dubinina-Radushkevicha.

6

Development of Adsorbent from Phytoremediation Plant Waste for Methylene Blue Removal

Alshekhli Atyaf Farooq, Hasan Hassimi Abu, Muhamad Mohd Hafizuddin, Abdullah Siti Rozaimah Sheikh

Journal of Ecological Engineering

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2020

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Vol. 21, nr 8

207--215

EN

Dyes are considered to be hazardous, have low biodegradability and can affect the human health as well as the aquatic life cycle. This research investigated the methylene blue (MB) removal using an activated carbon matrix of Scirpus grouss (waste that was initially used for phytoremediation of soil). The experiment was conducted in a flask containing 0.5 g AC-SC with MB concentrations of 5 and 15 mg/L. The adsorption was monitored for 120 sec. The results showed complete removal of MB within a contact time of 30 sec using 6-AC. The surface morphology analysis showed that at 6-AC, the structure was more porous. The ultimate potential of activated carbon prepared from the phytoremediation plant waste would be the best alternative for the water and wastewater treatment, while it provides an alternative to the phytoremediation waste management process.

7

Removal of acid, direct and reactive dyes on thepolyacrylic anion exchanger

Polska-Adach Ewelina, Wawrzkiewicz Monika, Hubicki Zbigniew

Physicochemical Problems of Mineral Processing

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2019

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Vol. 55, iss. 6

1496--1508

EN

In the present studythe polyacrylic anion exchanger Amberlite IRA 478 (IRA 478) was used forremoval of textile dyes such as C.I. Acid Red 18 (AR18), C.I. Reactive Blue 21 (RB21) and C.I. Direct Yellow 142 (DY142) from aqueous solutions. Sorption of the above-mentioned dyes was carried out by the static and dynamic methods. The obtained results were analyzed by determining the adsorption isothermparameters using the Langmuir and Freundlichmodels. Kinetic parameters of dyessorption were calculated from the pseudo-first order, pseudo-second order and intraparticle diffusion models. The monolayer sorption capacities of IRA 478 determined from the Langmuir isotherm were found to be 1098.5 mg/g for AR18 (R2=0.994), 46.8 mg/g for DY142 (R2=0.820) and 23.5 mg/g for RB21 (R2=0.987).Kinetic studies revealed that effectiveness of AR18, DY142 and RB21 uptakeincreases with increasing phase contact time and initial dyesconcentration.The kinetics of the dyessorption process on the anion exchanger is best described by the pseudo-second order model (PSO) due to the high values of the determination coefficients R2 (linearity condition of the plot t/qt vs.t). The rate constantsof the pseudo-second order kinetics k2are reduced from 0.1001 to 0.0008 g/mg·min for AR18, from 0.0147 to 0.0112 g/mg·min for DY142 and 0.0489 to 0.0072 g/mg·min for RB21 with an increase of initial concentration of dyes.The presence of salts and surfactants had an impact on the retention of direct and reactive dyes.

8

Isotherm studies of malachite green removal by yarn processing sludge-based activated carbon

Tang Shu Hui, Zaini Muhammad Abbas Ahmad

Chemistry-Didactics-Ecology-Metrology

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2019

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R. 24, NR 1-2

127--134

EN

Adsorption is an effective wastewater treatment technique which has been widely used in various industrial applications. However, the high operation cost involving commercial activated carbon in industrial processes is the main drawback. Sewage sludge is an auspicious precursor of activated carbon owing to its high carbon content, rich functional groups, low cost, high availability and abundance. This research was aimed to establish the feasibility of converting yarn processing sludge into activated carbon by KI + KOH activation and char at 700 °C for 1 h. The effect of preparation strategies on the properties of sludge-based adsorbents (SBA) was reviewed. The applications of SBAs in the removal of dyes and model pollutants were discussed. The results from this study proved that the preparation of yarn processing sludge-based activated carbon via KI + KOH activation is feasible and effective in the adsorption of dye. This paper provides further insight on the preparation methods of sludge-based adsorbents and dye wastewater treatment using these adsorbents.

9

Dye removal using keggin polyoxometalates assisted ultrafi ltration: characterization and UV visible study

Kahloul Malak, Chekir Jalila, Hafiane Amor

Archives of Environmental Protection

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2019

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Vol. 45, no. 4

30--39

EN

To improve dye retention, there is a concurrent interest in the development and optimization of an alternative and promising method for the dye recovery in aqueous solutions. In this regard, considerable attention was paid to the polyoxometalates (POMs) assisted ultrafiltration (POMAUF). The aim of the present study is to eliminate toluidine blue (TB) dye by ultrafiltration membrane using keggin polyoxometalates (POMs) as complexing agents. In the first step, the keggin polyoxometalates K3[PW12O40]∙6H2O (PW12) and K7 [PW11O39]∙14H2O (PW11) were prepared. Then, the obtained powders were characterized by X-ray diffraction and infrared spectroscopies. Afterwards, the removal of toluidine blue (TB) using polyoxometalates assisted ultrafiltration (POMAUF) was studied. Factors affecting the retention of dye and permeate flux such as transmembrane pressure, operating time, polyoxometalates concentration, ionic strength, surfactant and pH were investigated. All results of both compounds have been presented and discussed. The results reveal that the addition of POMs leads to an increase in dye retention from 11 to 95% for the PW12 and to 98% for the PW11. The results of this work have thus suggested the promising enhancement of ultrafiltration membrane selectivity for the dye removal using new complexing agents such as POMs in place of polyelectrolytes and surfactants.

10

The effect of external mass transfer resistance on the adsorption rate in a liquid phase

Piątkowska S., Gwadera M.

Technical Transactions

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2018

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Vol. 115, iss. 3

79--90

EN

The paper presents the results of studies on the adsorption of a dye from a water solution on activated carbon. An activated carbon with the best adsorption properties for the dye used in the studies was selected experimentally. The equilibrium and kinetic measurements for the selected system were conducted. Constants of linear, Langmuir and Freundlich isotherms were determined. The obtained results have shown that increasing the flow rate of the solution in an adsorber results in increasing the adsorption rate.

PL

W pracy zaprezentowano wyniki badań adsorpcji barwnika z roztworu wodnego na węglu aktywnym. Dokonano eksperymentalnego doboru węgla aktywnego o najlepszych właściwościach adsorpcyjnych dla stosowanego w badaniach barwnika. Wykonano badania równowagi i kinetyki adsorpcji dla badanego układu. Wyznaczono stałe w równaniu izotermy liniowej, Langmuira i Freundlicha. Otrzymane wyniki wskazują, że zwiększenie natężenia przepływu roztworu w adsorberze skutkuje zwiększeniem szybkości adsorpcji.

11

Application of Spontaneous Oxidation Processes of Zero-valent Iron and Electrocoagulation for Reactive Black 5 Removal

Wysocka I., Filipkowska U., Jóźwiak T.

Fibres & Textiles in Eastern Europe

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2017

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Vol. 25, no. 4 (124)

121--128

EN

Two methods of Reactive Black 5 dye removal were compared in this work, namely electrocoagulation (EC) and one based on spontaneous electrochemical oxidation of zero-valent iron (ZVI). Both methods are based on electrode processes and the sorption process and allow to achieve a similar effectiveness of dye removal. In the case of ZVI, however, a longer contact time or a greater surface area of the electrodes applied is necessary. In turn, the ZVI enables to conduct the processes of dye removal with no requirement for an external source of electric current (lower exploitation inputs). The study demonstrated that the application of both the ZVI method and EC is especially advisable in the case of lower initial concentrations of dye in the solution, i.e. the higher the concentration, the lower the contribution of electrode processes in dye removal from the solution and the greater the contribution of sorption processes.

PL

W ramach niniejszej pracy porównano dwie metody usuwania barwnika Reactive Black 5. Metodę elektrokoagulacji (EC), oraz metodę opartą na samorzutnym elektrochemicznym utlenianiu żelaza na 0 stopniu utlenienia (ZVI). Obie metody wykorzystują procesy elektrodowe oraz procesy sorpcji, umożliwiając uzyskanie podobnej efektywność usuwania barwnika. W przypadku ZVI wymagany jest jednak dłuższy czas kontaktu, lub większa powierzchnia zastosowanych elektrod. ZVI umożliwia jednak przeprowadzenie procesów usuwania barwy, bez konieczności stosowania zewnętrznego źródła prądu (mniejsze nakłady eksploatacyjne). Badania wykazały, że zastosowanie zarówno metody ZVI i EC ma szczególne uzasadnienie w przypadku niższych stężeń początkowych barwnika w roztworze. Im wyższe stężenie, tym udział procesów elektrodowych w usuwaniu barwy roztworu jest mniejszy a przewagę zyskują procesy sorpcji.

12

Badania nad usuwaniem barwnych związków organicznych ze ścieków z przemysłu włókienniczegoBadania nad usuwaniem barwnych związków organicznych ze ścieków z przemysłu włókienniczego

Dąbek L., Ozimina E., Picheta-Oleś A.

Rocznik Ochrona Środowiska

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2013

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Tom 15, cz. 2

1164--1176

EN

The manuscript presents the results of the research regarding the efficiency of removal of coloured organic compounds from textile industry wastewaters with the use of Fenton reaction and simultaneous process of sorption and oxidation in the presence of activated carbon and hydrogen peroxide (or magnesium peroxide) as well as in the presence or absence of UV radiation. The most efficient method – guaranteeing the oxidation of organic compounds and decolourization of the solution indicated by the 80% reduction in COD (as compared to the initial value) within the period of 1 h – was the use of Fenton reaction. The application of combined processes of sorption and oxidation with the use of activated carbon and hydroxen peroxide in order to remove the organic pollutants from the examined wastewaters resulted in 64% reduction in COD, but only after 24 hours. Replacing hydrogen peroxide with magnesium peroxide accelerated the process of sorption and / or oxidation of organic pollutants leading to 50% reduction in COD after 2 hours of reaction. At the same time, initiating the decomposition of H2O2 with the formation of OH* radicals in the activated carbon/hydrogen peroxide system resulted in an effective decomposition of organic compounds, which is indicated by 60% reduction in COD after 2 hours. This solution appears to be the most promising, since after the separation of activated carbon (which can be further re-used) a colourless, transparent solution of pH of 6,5 – 7,5 is obtained, which can be disposed into the municipal sewage system.

13

Biosorpcja barwników z użyciem materiałów pochodzenia roślinnego

Witek-Krowiak A.

Przemysł Chemiczny

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2012

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T. 91, nr 4

613-620

PL

Zaprezentowano przegląd literatury dotyczącej usuwania barwników organicznych z roztworów wodnych z zastosowaniem biosorpcji. W szczególności przedstawiono wyniki badania biosorpcji na różnorodnych materiałach pochodzenia roślinnego, w tym nadziemnych częściach roślin (drewno, pędy, kora, liście), fragmentach roślinnych, a także na materiałach odpadowych z przemysłu spożywczego (pestki, nasiona, łupiny orzechów, wytłoki). Materiały te stanowią grupę sorbentów tanich i wydajnych, będących konkurencją dla konwencjonalnych sorbentów, dzięki dużym pojemnościom sorpcyjnym względem usuwanych związków.

EN

A review, with 113 refs., of plant materials used as biosorbents for removal of org. dyes from aq. solns.

14

Dye removal efficiency of virgin activated carbon and activated carbon regenerated with Fenton's reagent

Dąbek L., Ozimina E., Picheta-Oleś A.

Environment Protection Engineering

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2012

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Vol. 38, nr 1

5-13

EN

The effectiveness of virgin and regenerated activated carbons was established for crystal violet removed from aqueous solutions. Granular activated carbon, WDex, saturated with the dye was regenerated using classic or modified Fenton's reagent, Fe2+/H2O2 and Fe2+/Ox, respectively. The application of modified Fenton's reagent resulted in the formation of hydrogen peroxide directly in the regeneration solution. The study was conducted under static and dynamic conditions. The sorptive capacities of virgin and regenerated WDex activated carbons for crystal violet were reported to be similar (approximately 42 mg/g). The results of the dynamic sorption show that under the predetermined conditions the regenerated activated carbons were better sorbents. The amount of dynamic sorption was approx. 17.6 g/dm3. The longest breakthrough time (3970 min) and the longest saturation time (11 600 min) were observed for the carbon bed regenerated with modified Fenton's reagent.

15

Badania przydatności membran ceramicznych do usuwania barwników organicznych z roztworów wodnych

Majewska-Nowak K., Kawiecka-Skowron J.

Ochrona Środowiska

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2009

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Vol. 31, nr 2

55-60

PL

Określono skuteczność usuwania anionowych barwników organicznych z modelowych roztworów wodnych w procesie ultrafiltracji z użyciem membran ceramicznych. Do oceny właściwości transportowych i separacyjnych membran ceramicznych wykorzystano strumień objętości permeatu oraz skuteczność usuwania barwnika z roztworu. W badaniach wykorzystano trzy jednokanałowe membrany ceramiczne CéRAM INSIDEŽ (Tami Industries), różniące się graniczną rozdzielczością (1 kDa, 15 kDA o 50 kDa). Badaniom poddano roztwory dziewięciu anionowych barwników organicznych o masie cząsteczkowej od 327 Da do 1060 Da. Badania przeprowadzono z wykorzystaniem laboratoryjnej instalacji ultrafiltracyjnej ProFlux M12 (Millipore) przy ciśnieniach transmembranowych 0,03 MPa, 0,06 MPa i 0,09 MPa. Analizowano wpływ masy cząsteczkowej barwnika oraz stosowanego ciśnienia na skuteczność procesu. Badania wykazały przydatność membran ceramicznych do usuwania barwników organicznych z roztworów wodnych. Stwierdzono, że membrana o granicznej rozdzielczości 15 kDa odznaczała się najlepszymi właściwościami separacyjnymi, podczas gdy membrana 50 kDa wykazywała znakomitą przepuszczalność. Wszystkie przebadane membrany ceramiczne pozwoliły na zatrzymanie barwników o dużej masie cząsteczkowej (>700 Da) w 95÷99%, niezależnie od wartości ciśnienia transmembranowego. Wykazano, że ekonomicznie uzasadnione jest stosowanie membran ceramicznych o granicznej rozdzielczości 50 kDa, gdyż membrany te zapewniają dużą wydajność przy dobrej skuteczności usuwania barwników o większych masach cząsteczkowych.

EN

Laboratory tests were conducted to determine the efficiency of anionic organic dye removal from aqueous solutions by ultrafiltration when use is made of ceramic membranes. The transport and separation properties of the membranes were evaluated by analyzing the volume flux of the permeate, and the efficiency of dye removal from the solution. The tests were performed with three single-channel CéRAM INSIDEŽ (Tami Industries) membrane modules differing in cut-off values (1 kDa, 15 kDa, and 50 kDa), with nine anionic organic dyes of molecular weights ranging from 327 to 1060 Da, and with a laboratory UF installation of ProFlux M12 (Millipore) type, at a transmembrane pressure of 0.03 MPa, 0.06 MPa and 0.09 MPa. The efficiency of the process was analyzed both in terms of the molecular weights of particular dyes and in terms of the pressure applied. The applicability of the ceramic membranes to the removal of organic dyes from aqueous solutions has been substantiated. The tests have produced the following findings. The ceramic membrane with the cut-off value of 15 kDa exhibited the best separation properties, whereas that with the cut-off value of 50 kDa was characterized by excellent permeability. All of the ceramic membranes under study provided 95-99% retention of high-molecular-weight organic dyes (>700 Da) irrespective of the transmembrane pressure applied. In economic terms, it is advisable to use 50 kDa cut-off ceramic membranes as they enable high removal efficiencies to be achieved for dyes of higher molecular weights.