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PL
Przegląd literaturowy dotyczący zastosowania materiałów mezoporowatych MCM-41 i MCM-48, także modyfikowanych organicznymi grupa mi funkcyjnymi, jako adsorbentów wybranych substancji o właściwościach przeciwutleniających. Dyskutowano zastosowanie adsorbentów jako nośników służących uwalnianiu wybranych kwasów fenolowych lub flawonoidów. Przedstawiono także adsorbenty o strukturze organicznej, dla substancji o charakterze flawonoidów.
EN
A review, with 22 refs., of the use of MCM-41 and MCM-48 mesoporous materials, also modified with org. functional groups, as adsorbents of selected substances with antioxidant properties. Adsorbents with org. structure applied to flavonoid compds. were also presented. The use of adsorbents as carriers for the release of selected phenolic acids or flavonoids was discussed.
PL
Porównano właściwości adsorpcyjne mezoporowatej krzemionki MCF oraz krzemionki koloidalnej (Aerosil®) wobec lidokainy jako modelowego leku miejscowo znieczulającego. Przeprowadzono matematyczną interpretację procesu adsorpcji, stosując modelowe izotermy Langmuira, Jovanovicia oraz Dubinina i Raduszkiewicza. Wykazano (izoterma Langmuira), że krzemionka MCF charakteryzuje się ponad dwukrotnie większą pojemnością adsorpcyjną (193,4 mg/g) wobec leku aniżeli krzemionka koloidalna (92,1 mg/g). Stosowane adsorbenty wykazały niewielką wydajność adsorpcji lidokainy w środowisku acetonitrylu, zaś dominującą siłą oddziaływania leku z powierzchnią krzemionek była adsorpcja fizyczna.
EN
Licodaine was adsorbed from its solns. in MeCN on a mesoporous MCF silica and colloidal Aerosil. A math. description of the adsorption process was performed using the Langmuir, Jovanovic and Dubinin-Radushkevich model isotherms. MCF silica was characterized by twice the adsorption capacity (193.4 mg/g) as compared to colloidal silica (92.1 mg/g). Used adsorbents revealed low adsorption capacity towards lidocaine in MeCN. Phys. adsorption was the main force of the drug-silica surface interactions.
3
Content available remote Symulacja adsorpcji Au na TS-1 z wykorzystaniem reakcji HOPO
PL
Obliczono energię adsorpcji atomów Au na sitach tytanowych wyko rzystywanych do epoksydacji propylenu do tlenku propylenu. War tości energii porównywano, wykorzystując moduły sorpcji i Forcite. Adsorpcja była głównie fizyczna, ale zaobserwowano również transfer elektronów na powierzchni styku Au-Ti, czyli adsorpcję chemiczną. Stanowiło to podstawę teoretyczną i kierunek dalszej optymalizacji struktury sita TS-1 z ładunkiem Au poprzez rozproszenie większej liczby cząstek Au w kanałach sita.
EN
Adsorption energy of Au atoms on Ti sieves used for HOPO reaction was calcd. and compared by using the sorption and Forcite modules. The adsorption was primarily phys. one, but some electron transfer at the Au-Ti contact surface was also obsd. as chem. adsorption. This provid ed a theor. basis and direction for further optimizing the Au-loaded TS-1 structure by dispersing more Au particles into the sieve channels.
PL
Przedstawiono wyniki badań dotyczących zastosowania mezoporowatej krzemionki SBA-15 jako adsorbentu lidokainy. Przeprowadzono modelowanie procesu adsorpcji z zastosowaniem wielu równań izoterm (Freundlicha, Langmuira, Jovanovicia oraz Dubinina i Raduszkiewicza). Wartości parametrów modeli matematycznych oszacowano metodą dopasowania nieliniowego. Izoterma Jovanovicia najlepiej opisywała adsorpcję lidokainy na krzemionce SBA-15. Wykazano (model Dubinina i Raduszkiewicza) fizyczny charakter odziaływań leku z powierzchnią adsorbentu SBA-15.
EN
Lidocaine was adsorbed from its solns. in MeCN on a SBA-15 mesoporous silica. The modeling of adsorption exptl. data was performed using several adsorption models such as Freundlich, Langmuir, Jovanovich and Dubinin-Radushkevich. The values of the math. model parameters were estimated using the nonlinear fitting method. The adsorption process onto SBA-15 silica was best described using Jovanovich isotherm. The phys. nature of the drug interactions with the SBA-15 adsorbent surface was demonstrated (Dubinin and Raduszkiewicz model).
PL
W badaniach właściwości adsorpcyjnych stosowano trzy adsorbenty (mech torfowy, polioctan celulozy i diatomit), dla których wyznaczono wielkość adsorpcji oleju napędowego. Do celów opisu kinetyki adsorpcji wykorzystano model izotermy Langmuira. Przeanalizowano strukturę zewnętrzną poszczególnych adsorbentów metodą mikroskopii skaningowej SEM i analizę pierwiastkową SEM-EDS. Adsorbenty charakteryzowały się znaczną zawartością węgla, tlenu i krzemu. Zauważalne były również śladowe ilości innych pierwiastków.
EN
Three adsorbents (peat moss, polycellulose acetate and diatomite) were used in the studies of adsorption of diesel oil at temp. of 293.15, 303.15 and 323.15 K. The Langmuir isotherm model was used to describe the adsorption kinetics. The anal. of the external structure of individual adsorbents was carried out using SEM, and the elemental anal. using SEM-EDS.
6
Content available remote Analiza wybranych konstrukcji wielozłożowego adsorpcyjnego układu chłodniczego
PL
Omówiono budowę i funkcjonowanie prostego, jednozłożowego adsorpcyjnego układu chłodniczego. Dokonano analizy wybranych konstrukcji układów wielozłożowych. Zweryfikowano opracowany prototyp własnego rozwiązania systemu adsorpcyjnego. Zaprezentowano przykładowe wyniki z weryfikacji układu, dla którego osiągnięto temperaturę w parowniku na poziomie ok. 6°C. Innowacyjnym elementem tego układu był kształt prototypowych adsorberów ze stali nierdzewnej, które są wykonane jako dwa różne rozwiązania konstrukcyjne: walcowo-krzyżowy i walcowo-rurowy. Prezentowane systemy adsorpcyjne, ze względu na swoje parametry pracy, mogą być wykorzystywane do zagospodarowania niskotemperaturowego ciepła odpadowego w przemyśle.
EN
The construction and operation of a simple single-bed adsorption refrigeration system were discussed. Selected designs of multi-bed systems were analyzed. A verified prototype of our own soln. of a threebed adsorption refrigeration system was presented. Examples of results from the verification of the system for which the temp. in the evaporator was reached at the level of approx. 6°C were presented. An innovative element of the system was the shape of the prototype stainless steel adsorbers, which were made in 2 different design solns.: cylindrical-cross and cylindrical-tube. Due to their operational parameters, the presented adsorption systems can be used for the management of low-temp. waste heat in industry.
EN
Wastewater generated during the production of pomace olive oil is complex and highly variable due to different cultivation and processing characteristics. It has a high toxic organic load, low pH, and high chemical and biological demands. To reduce the concentration of chemical oxygen demand (COD) and total phenolic compounds (TPh) in pomace olive oil wastewater, several treatment processes have been studied. These include: (i) coagulation/flocculation, (ii) electrocoagulation, (iii) peroxy-electrocoagulation, (iv) electrochemical peroxidation, (v) Fenton, (vi) electro-Fenton, (vii) photo-Fenton, and (viii) adsorption. Coagulation/flocculation and electrocoagulation resulted in a maximum COD removal of 16%, while techniques involving the addition of hydrogen peroxide (iii-vii) had an average of 78% TPh removal but only 20% COD removal. Adsorption resulted in a maximum of 29% COD and 75% TPh removal. None of the tested techniques were able to remove more than 50% of COD, indicating the difficulty of removing organic matter in this effluent. However, advanced oxidation techniques were effective in degrading phenolic compounds, although they required relatively high dosages of oxidant.
EN
The adsorption effect of two modified kaolin-chitosan composites prepared by different modification methods (cross-linking method (GL-CS) and click reaction method (TGL-CS) on lead ion wastewater was studied. The structure of TGL-CS has a denser pore structure than that of GL-CS, and the distribution of adsorption sites is more uniform. At 25 °C, pH 4, the adsorbent dosage of 0.05 g/dm3, reaction time of 4 h, and initial mass concentration of 150 mg/dm3, TGL-CS had the best effect on Pb2+ wastewater treatment, and the adsorption capacity was 76.159 mg/g. The adsorption studies of kinetic, thermodynamic, and thermodynamic parameters showed that the adsorption on GL-CS and TGL-CS was best described by the Langmuir model. The adsorption mechanism is mainly chemical adsorption. The adsorption process is spontaneous. These results show that the adsorbent prepared by click reaction has obvious advantages, with more adsorption capacity and adsorption sites, faster adsorption rate, and better application potential.
9
Content available remote Removal of textile dyes from water using cellulose aerogel
EN
In this study, removal of textile dyes from artificially contaminated water was investigated using sorbent synthesised from cardboard waste. Aerogel - lightweight adsorbent - a material with a low density and large surface area. Aerogels obtained from cellulose, chitosan, lignin or pectin have good adsorption properties for removing organic pollutants from wastewater. The aim of this study was to determine the adsorption efficiency of naphthol green B, congo red, methylene blue and rhodamine B from artificially contaminated water using sorbent synthesised from cardboard waste. The mass of the cellulose aerogel (5 mas. %) adsorbents, that were used in the experiments varied from 1.6 g to 2.74 g. The optimal adsorption conditions were determined as pH = 6.0, concentration of dyes - 10 mg L–1 and 18.0 °C -19.0 °C temperature. Under the optimal conditions, the maximum removal efficiency of naphthol green B using aerogel was 16.45 %; congo red - 98.44 %; methylene blue 79.28 %; and rhodamine B - 52.44 %.
10
Content available remote Application of fly ash/chitosan composites for heavy metal adsorption
EN
The aim of this paper is to investigate the potential of modified fly ash (FA) as an adsorbent for the removal of heavy metal ions from polluted waters. The effectiveness of unmodified FA was compared to FA modified with chitosan. The FA and FA/chitosan particles were characterized by means of SEM, XRF and FTIR methods. The FA and FA/chitosan composites were investigated as adsorbents for Cu(II) and Pb(II) ions from aqueous solutions. Experiments were carried out in a previously optimized pH (pH = 6), at room temperature for 3 hours. Langmuir and Freundlich isotherms were used to determine the maximum adsorption capacities of the fly ash samples for Cu(II) and Pb(II) ions. The experimental data indicate that the Langmuir isotherm fits better than the Freundlich isotherm for all the investigated systems. The obtained values of the qm, maximum adsorption capacity for the removal of Cu(II) and Pb(II) with the FA/chitosan composites were (1.068, 1.00, 1.042, 1.369 mg/g), and (2.532, 2.063, 1.036, 2.146, 2.482 mg/g), respectively. The efficiency trend was Pb(II) > Cu(II). The results indicate that the removal efficiency for Cu(II) and Pb(II) ions was 91.1 % and 99.7 %, respectively.
EN
With constantly increasing ecological needs, it is necessary to look for suitable solutions aimed at purifying the water and soil environment. Synthetic zeolites, i.e. porous, ion-exchangeable, acid- and heat-resistant, sodium and calcium aluminosilicates, may be the answer to this demand. This paper presents the adsorption capabilities of two synthetic zeolites (Na-X, Na-P1) obtained via hydrothermal reaction of aqueous sodium hydroxide and high-carbon fly ash. For this purpose, the experiment was conducted with adsorbates from two groups: heavy metals (Pb(II), Zn(II)) and organic substances (polymer - poly(acrylic acid) (PAA), nonsteroidal anti-inflammatory drug – diclofenac (DCF)). Adsorption was carried out in single and mixed adsorbate systems (metal-metal; metal-organic substance; organic substance-organic substance). The adsorption capacity of the studied zeolites was determined relative to Pb(II), Zn(II) and DCF. Desorption processes were also carried out to illustrate the regeneration abilities of the examined porous materials. In addition, the structure of the electrical double layer was characterized using potentiometric titrations and electrophoretic mobility measurements. The highest adsorbed amounts of heavy metals in single systems are observed for Na-X, i.e. 322.1 mg/g Pb(II) and 332.5 mg/g of Zn(II). In the case of Na-P1 zeolite, these amounts were 332.9 mg/g and 103.6 mg/g for Pb(II) and Zn(II), respectively. In mixed adsorbate systems there is a decrease in heavy metal adsorption, after the addition of both another metal or organic substance. In the first case, the decrease is small - the adsorption of Pb(II) on Na-X drops to 309.36 mg/g. In contrast, in mixed systems in the presence of anionic organic substances, the decrease in the amount of adsorbed ions is much greater. In the presence of DCF, Pb(II) adsorption on Na-X decrease to 98.7 mg/g, whereas on Na-P1 to 99.7 mg/g. The main mechanisms of the adsorption process in such systems are: competition for the adsorbent's active sites and the formation of complexes between adsorbates of opposite ionic character. However, the addition of a heavy metal causes increase of the drug adsorption. In the case of Pb(II) ions, the amount of DCF adsorbed on Na-X increases from 6.68 mg/g to 12.86 mg/g, and a slight decrease is observed on Na-P1. On the other hand, in the presence of PAA, DCF adsorption on Na-X decreases to 5.86 mg/g. Moreover, the synthesized adsorbents can be successfully regenerated with hydrochloric acid (in the single and mixed systems containing heavy metals). The addition of Pb(II)/Zn(II) and PAA causes a decrease in the zeta potential of the examined zeolites, whereas the addition of DCF increases this parameter. In turn, the surface charge density decreases in the presence of each adsorbate. It was proved that both synthetic zeolites can be successfully used in soil and water purification processes in continuously improved procedures.
PL
Celem pracy było określenie skuteczności zintegrowanej koagulacji i sorpcji na poprawę podstawowych wskaźników wody takich jak: mętność, barwa i absorbancja UV254nm. W artykule przedstawiono wyniki badań wody podczas procesu koagulacji i zintegrowanego procesu koagulacji i sorpcji. Do analizy wybrano koagulanty wstępnie zhydrolizowane - FLOKOR1ASW, FLOKOR1,2A oraz FLOKOR15 oraz pylisty węgiel aktywny CWZ-22. Próbki wody poddane koagulacji oraz koagulacji i sorpcji pobrano z rzeki Wisty. Koagulanty w zintegrowanym procesie dozowano w optymalnej dawce wynoszącej 3,5 mg Al/dm3, a pylisty węgiel aktywny w dawkach od 20 do 100 mg/dm3. Podczas procesu najwyższe efektywności usunięcia mętności, barwy i absorbancji UV2M wynosiły odpowiednio 99,5 i 93,2 oraz 70,4%.
EN
The aim of the study was was to determine the effectiveness of integrated coagulation and sorption on the improvement of basie water indicators such as: turbidity, color and absorbance UV254nm. The article presents the results of water tests during the coagulation process and the integrated process of coagulation and sorption. Pre-hydrolyzed coagulants - FLOKOR1ASW, FLOKORB1,2A and FLOKOR1S and powder-activated carbon CWZ-22 were selected for the analysis. Water samples subjected to coagulation as well as coagulation and sorption were collected from the Vistula river. Coagulants in the integrated process were dosed in the optimal dose of 3.5 mgAI/dm3, and powder-activated carbon in doses from 20 to 100 mg/dm3. During the process, the highest turbidity, color and absorbance UV2H removal efficiencies were 99.5, 93.2 and 70.4%, respectively.
PL
Łupiny orzechów laskowych, produkt uboczny przemysłu spożywczego, mają znaczny potencjał jako prekursor do produkcji węgla aktywnego ze względu na ich dużą dostępność i dużą zawartość węgla. Przedstawiono badania możliwości przekształcenia łupin orzechów laskowych w węgiel aktywny, wykorzystany do oczyszczania ścieków z zanieczyszczeń organicznych. Porównano procesy aktywacji fizycznej i chemicznej otrzymanego węgla. Otrzymano wysoce porowaty materiał o powierzchni właściwej 1211 m²/g. Ponadto przedstawiono izotermy adsorpcji i oznaczono pojemność adsorpcyjną biowęgla względem rodaminy B.
EN
Hazelnut shells were pyrolyzed at 500°C for 1 h. The obtained biochar was activated phys. with CO₂ at 800°C or chem. with KOH at 850°C. A porous material with a sp. surface area of 1211 m²/g was obtained. The adsorption properties of activated C were tested in relation to the adsorption of rhodamine B. The adsorption capacity was 64.4 mg/g. The Langmuir, Freundlich, Sips and Toth adsorption equil. models were used to describe the rhodamine adsorption isotherm. The best fit to the exptl. data was observed for the Sips isotherm.
EN
The effect of coating silica with polyethylene glycol on the adsorption of iron and phosphate ions in industrial wastewater was investigated. Variable factors were temperature and time of coating, PEG concentration, and PEG to silica ratio. Infrared spectroscopy and scanning electron microscopy were used to evaluate the chemical structure and morphology of PEG-coated silica. Optimum iron and phosphate ions removal efficiency was obtained using a coating temperature of 50°C, a coating time of 15 min, a PEG concentration of 20%, and a PEG to silica ratio of 1:3.
PL
Zbadano wpływ powlekania krzemionki glikolem polietylenowym na adsorpcję jonów żelaza i fosforanów ze ścieków przemysłowych. Czynnikami zmiennymi były temperatura i czas powlekania, stężenie PEG oraz stosunek PEG do krzemionki. Do oceny budowy chemicznej i struktury krzemionki powlekanej PEG stosowano spektroskopię w podczerwieni i skaningową mikroskopię elektronową. Optymalną skuteczność usuwania jonów żelaza i fosforanów uzyskano stosując temperaturę powlekania 50°C, czas powlekania 15 minut, stężenie PEG 20% oraz stosunek PEG do krzemionki 1:3.
EN
The main product of the conversion of ethanol to acetone on a ZnO-CaO catalyst is acetone, the yield of which strongly depends on the composition of the reaction environment. When oxygen is present, the yield of products of destructive and complete oxidation increases greatly. In contrast, when water vapor is present, both the selectivity and conversion of ethanol increase. Therefore, the conversion of ethanol is the limiting step in the overall process, which determines the selectivity of the conversion of ethanol to acetone. In this regard, it appeared suitable to investigate the effect of introducing water to the contact zone. As experiments indicated, the addition of water caused a significant effect on the conversion, selectivity, and acetone yield on the ZnO-CaO catalyst. As the partial pressure of water vapor increases, the conversion of ethanol and the acetone yield increase, while the yield of carbon dioxide decreases. The decrease in carbon dioxide is associated not only with the inhibition of the conversion of ethanol to CO2. In this study, the adsorption of water vapor and ammonia on the surface of the ZnO-CaO catalyst was examined by infrared spectroscopy method. It has been shown that water vapor at low temperatures is adsorbed on the catalyst surface in the molecular form, while at higher temperatures it is adsorbed in the dissociative form. Co-transformation reactions of ethanol with acetic acid, acetaldehyde with ethylene, and acetaldehyde with acetic acid have been studied. The obtained results indicated that acetone is formed mainly through the stage of complexation of acetaldehyde with ethylene. The isomerization reaction of 1-butene to 2-butene has been investigated. It was found that the yield of cis-2-butene in the absence of water vapor is higher, likely attributed to the molecular adsorption of water on Lewis centers. Based on these findings, a scheme for the vapor-phase conversion of ethanol into acetone on the studied catalysts was formulated.
PL
Głównym produktem konwersji etanolu do acetonu na katalizatorze ZnO-CaO jest aceton, którego wydajność silnie zależy od składu środowiska reakcji. W obecności tlenu znacznie wzrasta wydajność produktów destrukcyjnego i całkowitego utlenienia. Natomiast w obecności pary wodnej wzrasta selektywność i konwersja etanolu. Dlatego konwersja etanolu jest etapem ograniczającym w całym procesie, który określa selektywność konwersji etanolu do acetonu. W związku z tym celowe wydawało się zbadanie wpływu domieszek wody do strefy kontaktu. Jak wykazały doświadczenia, dodatek wody miał istotny wpływ na konwersję, selektywność i wydajność acetonu na katalizatorze ZnO-CaO. Wraz ze wzrostem ciśnienia cząstkowego pary wodnej wzrasta konwersja etanolu i wydajność acetonu, podczas gdy wydajność dwutlenku węgla maleje. Spadek dwutlenku węgla jest związany nie tylko z hamowaniem konwersji etanolu do CO2. W niniejszej pracy metodą spektroskopii w podczerwieni badano adsorpcję pary wodnej i amoniaku na powierzchni katalizatora ZnO-CaO. Wykazano, że para wodna w niskich temperaturach jest adsorbowana na powierzchni katalizatora w postaci cząsteczkowej, natomiast w wyższych temperaturach jest adsorbowana w postaci dysocjacyjnej. Zbadano reakcje kotransformacji etanolu z kwasem octowym, aldehydu octowego z etylenem i aldehydu octowego z kwasem octowym. Uzyskane wyniki wykazały, że aceton powstaje głównie na etapie kompleksowania aldehydu octowego z etylenem. Zbadano reakcję izomeryzacji 1-butenu do 2-butenu. Stwierdzono, że wydajność cis-2-butenu w nieobecności pary wodnej jest większa, co prawdopodobnie wynika z molekularnej adsorpcji wody na centrach Lewisa. Na podstawie uzyskanych wyników zaproponowano schemat przemiany etanolu do acetonu w fazie gazowej na badanych katalizatorach.
PL
Celem badań było porównanie skuteczności usuwania WWA ze środowiska wodnego w wyniku sorpcji na biowęglach otrzymanych z pomiotu kurzego oraz komunalnych osadów ściekowych. Proces sorpcji prowadzono dla dawek biowęgli 50 i 100 mg/l. Dla każdej dawki biowęgla czas kontaktu z WWA wynosił 90 i 120 minut. Najlepsze wyniki uzyskano dla dawki biowęgla 100 mg/l i czasu kontaktu 120 minut. Dla biowęgla z pomiotu kurzego i z osadu ściekowego stężenie benzo(a)pirenu obniżyło się odpowiednio o 87,2 i 78,7% natomiast dla czterech WWA normowanych w wodzie przeznaczonej do spożycia sumaryczne stężenie obniżyło się odpowiednio o 83,5 i 80,2%. Dla pozostałych WWA większą sorpcję zaobserwowano dla dibenzo(a,h)antracenu, stężenie tego związku obniżyło się o 83,2%. Najmniejsze zmiany wykazano dla naftalenu, którego stężenie zmniejszyło się o 68,5%. Nie wykazano istotnych statystycznie różnic pomiędzy sorpcją na biowęglu z pomiotu kurzego i osadu ściekowego.
EN
The aim of the study was to compare the effectiveness of removing PAHs from the aquatic environment as a result of adsorption on biochars obtained from chicken manure and municipal sewage sludge. The sorption process was carried out for doses of biochars of 50 and 100 mg/L. For each dose of biochar, the contact time with PAHs was 90 and 120 minutes. The best results were obtained for a biochar dose of 100 mg/L and a contact time of 120 minutes. For biochar from chicken manure and sewage sludge, the concentration of benzo(a)pyrene decreased by 87.2 and 78.7%, respectively, while for four PAHs standardized in drinking water, the total concentration decreased by 83.5 and 80.2%, respectively. For the remaining PAHs, higher sorption was observed for dibenzo(a,h)anthracene, the concentration of this compound decreased by 83.2%. The smallest changes were shown for naphthalene, the concentration of which decreased by 68.5%. There were no statistically significant differences between sorption on biochar from chicken manure and sewage sludge.
EN
Fluorine-containing wastewater from the Yuncheng Sewage Treatment Plant in Heze City, Shan-dong Province was treated by coagulation and precipitation with poly aluminum sulfate, and CaO chemical precipitation-activated carbon adsorption, with a view to reducing fluoride ions concentration in the wastewater to below the discharge standard. The results showed that the optimum conditions for the coagulation-sedimentation test of poly aluminum sulfate were as follows: the dosage of poly aluminum sulfate 0.3 g/dm3, initial pH value 4.0, the removal rate of fluoride ion in the fluorine-containing wastewater reached 98.46%, and the concentration of fluoride ion was 0.462 mg/ dm3, which reached the discharge standard (1.5 mg/ dm3); The optimum conditions for the CaO chemical precipitation, and lanthanum loaded activated carbon adsorption method were as follows: the amount of CaO 20 g/ dm3, initial pH of the chemical precipitation test 8.0, the dosage of lanthanum loaded activated carbon 10 g/ dm3, and the initial pH of the adsorption test 6.0. At this time, the removal rate of fluoride ions in the fluorine-containing wastewater reached 95.81%, and the concentration of fluoride ions was 1.26 mg/ dm3, which also met the discharge standard.
EN
Organic substances in water, both of natural and synthetic origin, especially their share in water treatment by-products can pose a threat to drinkers. That is why adsorption, as a very effective process of dissolved organic compounds removal is commonly used in surface water treatment systems. For process design and optimization, mathematical models both mechanistic and statistics are created. The results of the investigation of granular activated carbon (GAC) bed adsorption in a pilot plant with a capacity of 3 m3/h have been presented. Two systems have been tested – without ozonation and with ozonation before GAC adsorption. The models of the kinetics of GAC adsorption capacity exhaustion, the model of minimal GAC bed depth (adsorption zone) for assumed process efficiency (C/CO), as well as the model of adsorption zone movement velocity to the bottom of GAC bed, have been created. For the state of adsorptive equilibrium, the first model enables the determination of the isotherm parameters of the Freundlich type, the two other models are used for the calculation of GAC bed run time for the certain bed depth and assumed efficiency. It has been shown that in this case (water pollution, GAC type, pretreatment) ozonation plays a minor role.
EN
Indoor activities involving cooking and warming, outdoor sources, smoking, and candle and in-cense burning may introduce a massive portion of polycyclic fragrant hydrocarbons. These are well known for their mutagenicity and carcinogenicity and are omnipresent in urban situations as a result of the combustion of fuel. Due to small particle size, penetration has been suspected to be one major source of indoor polycyclic aromatic hydrocarbons. In the current study, the manufacturing of three types of filters (electrostatic charge-based, pomegranate peel biochar-based, and birds’ feathers-based) was carried out. Their efficiency was tested to remove molecules bounded PAHs and also other geno-toxic compounds associated with these particles. The electrostatic filter was more efficient (27.42%) than pomegranate peel-based and birds’ feathers-based filters (13.86% and 8.32%, respectively). The carcinogenetic effects of PAHs emitted from outdoor and indoor pollutants can be reduced using these kinds of filters.
EN
The research conducted here will hopefully lead to the creation of a practical, inexpensive method for purging aqueous solutions of contaminating phenolic chemicals. A biosorbent system comprised of eggshells and iron was studied for its potential to effectively detoxify phenol. Both the eggshell and the iron systems were used in the preparation of the adsorbents in order to achieve the desired result of having the properties of both systems. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) were used for characterisation. Batch tests were conducted to evaluate the adsorption capacity of eggshells and iron under the influence of different operating parameters (shaking speed, pH, initial phenol content, and contact time). In the design-expert modelling, the optimisation conditions were found to be a pollutant concentration = 30.0 mg . L–1, pH of 3.00, adsorbent dose = 0.11 mg . L–1, shaking speed = 150 rpm, and time = 120 min for an phenol reduction rate of 94.4 % which it was extremely near to the experimentally value (96.6 %). The CCD modelling that was performed in the RSM verified the findings that were predicted. On the basis of laboratory results, the prediction proved accurate.
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