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EN
Most methods used for the synthesis of functional nanomaterials contribute to the increasing amount of waste solvents. An environmentally friendly solution of this issue is the utilization of “green” procedures for a large-scale production of materials such as mechanochemical synthesis. Although, the beginnings of mechanochemistry date back to ancient times, it nowadays experiences a renaissance and attracts a lot of attention. Recently, mechanochemistry has been successfully implemented for the synthesis of diverse carbonaceous materials, i.e., activated carbons, ordered mesoporous carbons, graphene-based materials and carbon nanotubes, the usage of which ranges from adsorption, catalysis to environmental and energy storage applications. Undoubtedly, it becomes quite universal and powerful synthesis method. Hence, a review summarizing the current accomplishments in this field is needed.
EN
The paper investigates whether time and doses of powder activated carbon (PAC) effect adsorption rates of organic contaminants from water and proposes a new model of volume adsorption. Depending on the nature of the organic compounds present in water, a general description of the adsorption process may require a linear combination of adsorption models running at different rates and at different parameters of adsorption isotherms. The model showed a good fit with the measured data and could be used in designing adsorption units at water or wastewater treatment plants. The proposed set of model equations enables to predict the effects of PAC adsorption in both plug flow reactors and homogeneous reactors.
PL
Artykuł bada, w jaki sposób czas i dawki proszku węgla aktywnego (PAC) wpływają na szybkość adsorpcji zanieczyszczeń organicznych z wody, i proponuje nowy model adsorpcji objętościowej. W zależności od charakteru związków organicznych obecnych w wodzie ogólny opis procesu adsorpcji może wymagać liniowej kombinacji modeli adsorpcji działających z różnymi prędkościami i przy różnych parametrach izoterm adsorpcji. Model, na którym przeprowadzono badania, wpasował się w przykładowe dane, więc można go wykorzystać do projektowania jednostek adsorpcyjnych w oczyszczalniach wody lub ścieków. Proponowany zestaw równań modelowych pozwala przewidzieć skutki adsorpcji PAC zarówno w reaktorach z przepływem tłokowym, jak i reaktorach homogenicznych.
PL
Przedstawiono wyniki badań nad możliwością wykorzystania aktywowanych pirolizatów ze zużytych opon do adsorpcji z wody modelowych herbicydów: kwasu 2,4-dichlorofenoksyoctowego (2,4-D), kwasu 2-metylo-4-chlorofenoksyoctowego (MCPA) oraz kwasu 2-metylo-4-chlorofenoksypropionowego (MCPP, Mecoprop). Adsorbenty otrzymano w wyniku aktywacji pirolizatów w atmosferze CO₂ w temp. 1100°C, stosując różne czasy procesu. Wielkość adsorpcji wszystkich badanych adsorbatów była skorelowana z czasem aktywacji i stopniem rozwinięcia struktury porowatej adsorbentu. Najlepszy z adsorbentów (135 min long aktywacji) miał powierzchnię BET równą 255 m²/g i całkowitą objętość porów równą 0,447 cm³/g. Dla wszystkich adsorbentów i adsorbatów adsorpcja najefektywniej przebiegała przy pH 2-3. Z testowanych trzech modeli izoterm adsorpcji: Freundlicha, Langmuira i Sipsa najlepszą zgodność danych doświadczalnych i modelowych uzyskano dla równania Sipsa. Aktywowane pirolizaty są skutecznymi i jednocześnie obiecującymi adsorbentami do usuwania herbicydów z wody. Zwiększenie ich pojemności adsorpcyjnej jest potencjalnie możliwe wraz z większym rozwinięciem powierzchni właściwej za pomocą aktywacji chemicznej.
EN
Three tire pyrolysis chars were activated in a CO₂ atm. at 1100oC and used as adsorbents for removal 2,4-dichlorophenoxyacetic acid, 2-methyl-4-chlorophenoxyacetic acid and 2-methyl-4-chlorophenoxypropionic acid from their aq. solns. The amt. of adsorbed acids was correlated with the activation time and the degree of adsorbent surface development. The best adsorbent had a sp. surface area of 255 m²/g and a total pore volume of 0.447 cm³/g after 135 min long activation. The best adsorption efficiency was achieved at pH 2-3. The best compatibility of exptl. and model data was obtained for the Sips model.
EN
In the process, inorganic complexes of amidoamines obtained from the interaction of natural petroleum acid and oleic acids with diethylenetriamine have been developed and their effectiveness as inhibitor-bactericides has been investigated. The effect of the synthesized reagents on the kinetics of the corrosion process of steel and the activity of sulphate-reducing bacteria in 3% NaCl solution saturated with CO2 and in the biphasic water–isopropyl alcohol medium with H2S dissolved has been analyzed. The thermodynamic and kinetic parameters of the corrosion process were calculated. The adsorption of the complexes was investigated using the Langmuir isotherm and the correlation constant was determined. State of the metal surface was investigated by SEM method in CO2 and H2S media, with and without inhibitors, and the metal surface contact of complexes was studied by computer molecular simulation.
PL
W artykule przedstawiono nowe podejście do interpretacji charakterystyki przestrzeni porowej, polegające na połączeniu pochodnych różnic objętości porowych – wyników porozymetrii rtęciowej i adsorpcji azotu na wspólnej skali, bez stosowania jakichkolwiek sztucznych przesunięć danych. To nowe podejście zastosowano wykorzystując wyniki pomiarów próbek łupków menilitowych pobranych z powierzchni terenu. Jest ono oparte na przyjętym założeniu, że w zakresie dowolnie wybranych średnic porowych istniejąca objętość porowa jest niezależna od użytego typu cieczy niezwilżającej (rtęć, ciekły azot, ciekły argon itp.). Jakiekolwiek różnice pomiarowe wynikające z tych dwóch pomiarów są konsekwencją mechanicznego pękania ścianek porów pod wpływem wysokich ciśnień rtęci lub też ich odkształceń elastycznych i\lub plastycznych oraz innych interakcji pomiędzy materiałem ścianek porów a zastosowaną cieczą niezwilżającą. Znaczące populacje porów w łupkach są zbyt małe, aby mierzyć je tylko za pomocą MICP (ang. Mercury Injection Capillary Pressure), co wyjaśniałoby niedoszacowanie całkowitej połączonej objętości porowej. Dlatego też do jej określenia zastosowano uzupełniającą metodę adsorpcji azotu. Struktura porowa próbek łupków menilitowych wygrzanych w 105°C była mierzona metodą porozymetrii rtęciowej w temperaturze otoczenia oraz metodą adsorpcji azotu w temperaturze wrzenia ciekłego azotu −195,8°C. Rozkłady pochodnych objętości względem średnicy porów otrzymanych z tych dwóch uzupełniających się metod zostały przedstawione w postaci wykresów zależności dV/dD. Na podstawie badań porozymetrycznych i piknometrii helowej obliczono porowatość całkowitą i otwartą, co pozwoliło na scharakteryzowanie własności filtracyjnych próbek skał. Na podstawie badań adsorpcyjnych obliczono powierzchnię właściwą BET, rozkład wielkości porów i zajmowaną przez nie objętość.
EN
In this paper, a new approach has been shown for the interpretation of the pore space characteristics, consisting in combining pore space volumetric fractional derivatives of mercury intrusion and nitrogen adsorption on the same scale without using any artificial data transformation. This new approach was shown using obtained results of measurements of surface Menilite Shales. It is based on the assumption that for any selected pore diameters, the existing pore space volume is independent of the applied non-wetting liquid agent (mercury, liquid nitrogen, liquid argon etc.). Any recorded differences of these two methods are due to cracking of pore walls under high mercury pressure or their elastic and/or plastic deformations and other interactions between pore building material and the non-wetting liquid used. Significant populations of pores in shales are too small to be measured using only MICP (Mercury Injection Capillary Pressure), which would explain the underestimation of the total porous space. Therefore, for its proper estimation, the complementary method of nitrogen adsorption has been used. The porous structure of Menilite Shale samples preheated at 105°C was measured using the mercury intrusion method MICP at ambient temperature and using nitrogen adsorption at its boiling point temperature of −195.8°C. Volumetric fractional derivatives of pore diameters obtained by these 2 different complementary methods were shown in the form of graphs dV/dD. Based on the porosimetric and helium pycnometric tests both bulk and open porosity was calculated, which allowed to characterise the filtration properties of rock samples. Based on the adsorption testing, the specific surface BET was calculated, as well as the pore size distribution and its total porous volume.
EN
In this work, lightweight granules of zeolite Na-P1 based on expanded glass aggregates were synthesized for the application in oil products’ sorption. The sorption of gasoline, diesel and silicone oil tests were also conducted for raw expanded glass, zeolite A, clinoptilolite and mineral sorbent available at a fuel station. All sorbents were also characterized in terms of the phase composition (X-ray diffraction) and structure (infrared spectroscopy). The zeolite Na-P1 granules achieved the highest values of sorption capacities (1.8, 2.1 and 2.6 g/g, respectively), which makes them promising materials for oils’ removal.
EN
A new composite adsorbent was prepared by modifying low cost local adsorbent (LCL) using MgFe layered double hydroxide (LDH). This low cost local adsorbent was also prepared from the activation of date palm leaf derived from agricultural waste. In comparison to the low LCL, the adsorption capacity of the new composite adsorbent (LCL/MgFe-LDH) was improved. This was measured in terms of its ability to remove lead from wastewater. The Scanning electron microscope (SEM), Energy dispersive spectroscopy (EDS), Fourier-transform infrared spectroscopy (FTIR) and the specific surface area by the (Brunauer, Emmett and Teller) theory (BET) tests were conducted for the characterisation of LCL and LCL/MgFe-LDH. The behaviour of the lead adsorption processes by using LCL/MgFe-LDH as adsorbent was investigated in batch experiments by examining different values of solution pH, contact time, adsorbent dose and initial Pb2+ concentration. High removal efficiency was exhibited by LCL/MgFe-LDH, a value almost double that of LCL. This was attributed to the increase in surface area of LCL/MgFe-LDH (79.7 m2·g–1) in contrast to the surface area of LCL (24.5 m2·g–1). The Freundlich equations and pseudo-second-order kinetics model were appropriate for the provision of adsorption equilibrium data for Pb2+ on adsorbents. These results reveal the great potential of the new composite adsorbent (LCL/MgFe-LDH) if applied to the absorption of heavy metal ions.
EN
The possibilities of using a natural sorbent – peat for the wastewater treatment of ammonium ions and phosphates discharged from runoff into natural reservoirs at high concentrations were investigated. The peat of from the Vereshchytsya-Yanovske deposit of Ukraine of two depths: lowland and upland, was studied. It was established that the lowland samples of peat have higher sorption properties to the investigated pollutants from the aquatic environment than the upland ones. A greater moisture loss in the lowland peat species was observed, as well as the major part of the plant fibers in its structure, which explains its sorption properties. Due to the high content of humic substances, the extraction of cations from the water by peat can occur due to the ion exchange. The adsorption isotherms of both ammonium and phosphate ions on the top and lowland peat species of the Vereshchytsya-Yanovske deposit were constructed and presented. The adsorption isotherm obtained in the experimental studies was used to mathematically establish the isotherm equation, using the Langmuir and Freundlich models to describe the equilibrium of the sorption processes under study. The degree of appropriation of linear equations to the experimental data was evaluated on the basis of the deterministic coefficient, which enabled to determine that in each case the Langmuir equations describe the adsorption isotherms more adequately.
EN
The purpose of the research was to synthesize new effective and cheap coagulants from industrial wastes (red mud) and study their coagulation properties on model water of textile industries, as well as develop a closed scheme of local wastewater treatment using the synthesized coagulants. Liquid coagulants, synthesized with the simple method, have better performance than commercial FeCl3, since not only iron but also aluminum and titanium compounds are present in the synthesized liquid coagulants, which makes them more effective. For the synthesized coagulants with a dose of 10 mg/l, the removal efficiency of the dyes mixture from the water was 99.7%, while for the commercial FeCl3, with a 2.5 times higher dose – only 95.4%. In the case of creating closed scheme of treatment and usage of the treated water with the coagulation method, an additional sorption purification step from the trace concentrations of pollutants was proposed. The usage of the new coagulants, synthesized from the wastes of alumina production in the proposed scheme will not only help reduce the environmental burden by minimizing the wastewater discharges into sewerage, but also recycle the accumulated environmentally hazardous “red mud” waste into commercial products.
EN
Zn/Cr and Zn/Cr layered double hydroxides (LDHs) intercalated with Keggin ion [α-SiW12O40]4-were successfully synthesized at room temperature and pH value of 10. The synthesized materials were characterized by means of the XRD, BET, and FT-IR analyses and used as an adsorbent iron(II). The adsorption process was investigated by studying pH, the kinetics, and thermodynamic properties of the adsorption process. The results showed the interlayer Zn/Cr LDHs was 7.53 Å and increase to 10.26 Å on Zn/Cr LDHs intercalated with Keggin ion [α-SiW12O40]4-. The BET analysis showed that the pore volume of both materials increased from 0.063 cm3 g-1 to 0.163 cm3 g-1. The pH point zero charge measurement for the Zn/Cr LDHs material was 10 while LDHs Zn/Cr intercalated with Keggin ion [α-SiW12O40]4- was 8. Zn/Cr LDHs intercalated with Keggin ion [α-SiW12O40]4- has higher adsorption capacity than Zn/Cr LDHs without intercalation. Desorption of iron (III) was successfully conducted using HCl as reagent showing the involvement of ion exchange in the adsorption.
EN
In the paper, the assessment of the impact of heavy metals on water objects, namely copper and chromium was performed, and the methods for their neutralization were defined. A scientifically grounded method for the selection of natural zeolite for the purification of wastewater from heavy metals has been developed, provided that they are jointly present. The physicochemical characteristics of two metals related to heavy metals are presented: copper and chromium. The methods for determining the sorption capacity of natural zeolite for copper and chromium compounds, as well as the methods of analytical control of the wastewater components were presented. The results of the experimental studies on the combined adsorption of copper and chromium cations by natural zeolite under static conditions were presented. The changes in the chemical composition of the zeolite surface as a result of heavy metal sorption have been investigated. The influence of the nature of the ions and the pH of the adsorption medium on the selectivity of the heavy metal ions extraction by zeolite was analyzed. A diagram of the composition of the solution, depending on the pH values, was constructed. The pH of the beginning of deposition of the corresponding heavy metal hydroxides on the zeolite surface was calculated. While analyzing the results of experimental studies on the combined adsorption of copper and chromium ions, it was found that the copper ions are significantly better adsorbed by the sorbent than the chromium ions. Despite the same concentration of the chromium and copper ions in solution, Cu2+ is extracted selectively. As can be seen from the results of experimental studies, the concentration of copper on the surface of the sorbent increases from 0.628% mass at a concentration of 0.01 g/dm3 to 47.380% mass at a concentration of 1 g/dm3. The studies on the static activity of clinoptilolite for the copper and chromium ions indicate a simultaneous mechanism of the process, which involves ion exchange and physical adsorption. The concentration of the chromium ions on the surface of the sorbent after adsorption depends on the increase of the concentration of Cr3+ in the original solution to a lesser extent. The results of the studies on the combined adsorption of the Cu2+ and Cr3+ ions indicate the possibility of their chromatographic separation, which makes their further use possible.
EN
Zeolites as a member of family of hydrated aluminosilicate minerals contains alkali and alkaline-earth metals. They are noted for their lability toward ion-exchange and reversible dehydration. Their framework structure encloses interconnected cavities occupied by large metal cations and water molecules. Bentonites are clays generated frequently from the alteration of volcanic ash, consisting predominantly of smectite minerals, usually montmorillonite. They present strong colloidal properties and its volume increases several times when coming into contact with water, creating a gelatinous and viscous fluid. The special properties of bentonite (hydration, swelling, water absorption, viscosity, thixotropy) make it a valuable material for a wide range of uses and applications. The purpose of this paper is to document an ability of a zeolite and bentonite to remove iron ions and various other pollutants from water. The surface analysis of zeolite and bentonite was performed by the very sensitive analytical device – XPS (X–ray photoelectron spectroscopy).
PL
Zeolity należą do rodziny uwodnionych minerałów glinowokrzemianowych, zawierających metale alkaliczne oraz alkaliczno-ziemne. Są zauważane ze względu na ich zdolność wymiany jonowej oraz odwrotnej dehydratacji. Ich struktura zawiera wewnętrznie połączone wgłębienia zajęte przez duże kationy metali oraz cząsteczki wody. Bentonity to iły tworzone często poprzez alterację popiołu wulkanicznego, zawierające głównie minerały smektytu a zazwyczaj montmorillonitu. Wykazują silne właściwości koloidalne a ich objętość wzrasta kilkukrotnie podczas wejścia w kontakt z wodą, tworząc w ten sposób galaretowatą i lepką ciecz. Specjalne właściwości bentonitu (hydratacja, puchnięcie, absorpcja wody, lepkość, tiksotropia) powodują, że jest to cenny materiał dla szerokiej gamy zastosowań. Celem tego artykułu jest udokumentowanie zdolności zeolitów oraz bentonitów do usuwania jonów żelaza oraz różnych innych zanieczyszczeń z wody. Analiza powierzchni zeolitu i bentonitu została wykonana za pomocą bardzo czułego urządzenia analitycznego – XPS (roentgenowska spektroskopia fotoelektronowa).
EN
The paper presents the results of experimental study of the adsorption characteristic of the IM-50 and tall oil fatty acids (TOFA) collector reagents on cassiterite. UV-spectrophotometric method, scanning electron and laser microscopy were applied to analyze the adsorption of the reagents. SHIMADZU UV 1800 was used to obtain the UV spectra of aqueous solutions of IM-50 reagents and saponified TOFA at varied concentrations. IM-50 has not got characteristic adsorption maxima in ultraviolet and visible spectrum. TOFA has a weakly pronounced maximum absorption in the range of 233-244 nm. Microscopic photographs of cassiterite sections were obtained with LEO 1420VP INCA equipped OXFORD ENERGY 350 analyzer. Reagent IM-50 and TOFA collector reagent, Newly formed organic matter phases of IM-50 and TOFA were detected. X-ray spectra characterized the increased carbon content indicating adsorption on the surface of cassiterite IM-5- and TOFA. By measuring the surface relief parameters of polished cassiterite, using KEYENCE VK-9700 scanning laser microscopy and VK-Analyzer software, a qualitative and quantitative assessment of the IM-50 and TOFA reagent layer on the cassiterite surface was performed. Measurements were performed in the several fields of view and showed the degree of IM-50 coating varied from 40.5 to 42.6% of the surface area, and TOFA average coating was 38.5%. Subsequent washing with water does not remove the reagents from the surface of the mineral and indicates a strong fixation of IM-50 and TOFA on cassiterite, which can have a positive effect on flotation extraction of sludge tin fractions. Qualitative and quantitative results of the reagent adsorption helped to make a forecast of their floatability by the studied collectors. This study is supported by the Russian Science Foundation (project No. 17-17-01292).
PL
W pracy przedstawiono wyniki badań eksperymentalnych charakterystyki adsorpcji odczynników kolektorowych IM-50 i kwasów tłuszczowych oleju talowego (TOFA) na kasyterycie. Do analizy adsorpcji odczynników zastosowano metodę spektrofotometryczną UV, skaningową mikroskopię elektronową i laserową. SHIMADZU UV 1800 zastosowano do uzyskania widm UV wodnych roztworów odczynników IM-50 i zmydlonego TOFA w różnych stężeniach. IM-50 nie ma charakterystycznych maksimów adsorpcji w widmie ultrafioletowym i widzialnym. TOFA ma słabo wyraźną maksymalną absorpcję w zakresie 233–244 nm. Zdjęcia mikroskopowe przekrojów kasyterytów uzyskano za pomocą analizatora OXFORD ENERGY 350 wyposażonego w LEO 1420VP INCA. Wykryto nowo powstałe fazy materii organicznej IM-50 i TOFA. Widma rentgenowskie charakteryzowały zwiększoną zawartość węgla wskazującą na adsorpcję na powierzchni kasyterytów IM-5- i TOFA. Mierząc parametry wypukłości powierzchni polerowanego kasyterytu, stosując skaningową mikroskopię laserową KEYENCE VK-9700 i oprogramowanie VK-Analyzer, przeprowadzono jakościową i ilościową ocenę warstwy odczynnika IM-50 i TOFA na powierzchni kasyterytu. Pomiary przeprowadzono w kilku polach widzenia i stwierdzono no stopień pokrycia IM-50 wahający się od 40,5 do 42,6% pola powierzchni, a średnie pokrycie TOFA wynosiło 38,5%. Późniejsze przemycie wodą nie usuwa odczynników z powierzchni minerału i wskazuje na silne utrwalenie IM-50 i TOFA na kasyterycie, co może mieć pozytywny wpływ na ekstrakcję flotacyjną frakcji szlamu i cyny. Jakościowe i ilościowe wyniki adsorpcji odczynników pomogły w opracowaniu prognozy ich flotowalności za pomocą badanych kolektorów. Badanie jest wspierane przez Russian Science Foundation (projekt nr 17-17-01292).
PL
W artykule przedstawiono jednowymiarowy model analityczny adsorpcyjnej pompy ciepła, porównując uzyskane wyniki przy zastosowaniu opisu równowagi adsorpcji równaniem Dubinina-Astachowa i równaniem równowagi Totha. Rozpatrywana jest jednostopniowa adsorpcyjna pompa ciepła silikażel – woda. Przyjęto, że adsorber zbudowany jest z rurek, na których osadzony jest adsorbent (silikażel). Opracowany model może posłużyć do określania charakteru pracy urządzenia oraz zmian temperatur, stężeń i strumieni ciepła w adsorberze/desorberze. Model został rozwiązany przy użyciu arkusza kalkulacyjnego. W obliczeniach prowadzonych z uwzględnieniem równania równowagi Totha zaobserwowano wyższe współczynniki SHP i SCP oraz wzrost ilości ciepła dostarczonego/ odprowadzonego do adsorbera, co wpłynęło na wzrost współczynników COP.
EN
In the presented paper the adsorber analytical modeling results based on Dubinin-Astakhov adsorption equilibrium and Toth adsorption equilibrium of water vapour on silica gel were compared. The adsorption heat pump with silica gel adsorbent and water adsorbate was discussed. A conventional single stage cycle adsorption heat pump is modeled. The design of the adsorber/desorber considered element is the tube with deposited silica gel bed. The analytical model was created to describe the temperature and concentration changes in the adsorber/desorber and consequently to describe the performance of the adsorption heat pump. The mathematical model was solved using common spreadsheet. A considerable increase in the calculated SHP and SCP in the model based on the Toth equilibrium equation as well as slight increase in the heat supplied or released from adsorbent influenced the increase in the COP.
15
Content available remote Study of methylene blue adsorption by modified kaolinite by dimethyl sulfoxide
EN
Tamazert kaolin was modified with dimethyl sulfoxide (DMSO). The starting material and resulting from the intercalation were characterized by X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy (SEM). Intercalation caused considerable changes in our clay by increasing the basal spacing to 11.22 Å, an intercalation rate of 98 %. The adsorption of methylene blue was studied as a function of pH, contact time, temperature, dye concentrations and adsorbents. Kinetic data have been adequately described by the pseudo-second order and intraparticle scattering model. The adsorption isotherm is in good agreement with the Redlich-Peterson model. A change in thermodynamic values (ΔH°, ΔS° and ΔG°) was observed after intercalation. Adsorption became non-spontaneous exothermic and ordered.
16
Content available remote Recycling of oil fly ash in the adsorption of dyes from industrial wastewater
EN
The use of oil fly ash after the recovery of heavy valuable metals was investigated. More specifically, its use, as an adsorbent of dyes from industrial wastewater, was evaluated. Methylene blue was used as a model compound to study the adsorption capacity of the proposed carbonaceous residue from metal recovery treatments. The effects of contact time, initial dye concentration, and absorbent dose were investigated. The maximum amount of dye was adsorbed after one hour. Moreover, 1-3 g of residues were necessary for the removal of 200-1000 mg dm–3 from 0.050 dm3 of contacted solution. The Langmuir isotherm model was in good agreement with the adsorption equilibrium data, indicating a maximum monolayer saturation capacity of approximately 40 mg/g at 25 °C. High abatement efficiencies (up to 99 %) were obtained, and the adsorbed dye was released almost immediately by re-contacting with water. The adsorption capacity was at least four times lower than that of commercially available active carbon. The double treatment of oil fly ash with deionised water and hydrochloric acid allows for the extraction of over 85 % of the vanadium, iron, and nickel content in the ash. However, the negligible or zero cost of solid residues, otherwise disposed in landfills, indicates their potential as a valid alternative. The use of oil fly ash for both recovery of heavy valuable metals and the subsequent removal of dyes from wastewater suggest a zero-waste process.
17
Content available remote Investigation of lead removal from drinking water using different sorbents
EN
Lead is a heavy metal with strong toxic properties. This chemical element is found in wastewater and sometimes in drinking water. The article deals with the removal of lead(II) ions from polluted water using a sorption process to determine the most effective sorbent for the removal of lead(II) ions. Three sorbents were used in the research: clay, sapropel, and iron sludge. All three sorbents investigated reduce the concentration of lead(II) ions in water: clay efficiency was of 65.7-90 %, sapropel of 94.3-100 %, and iron sludge of 84.3-97 %, depending on sorbent type and contact duration. The research has shown that the most effective way to remove lead(II) ions from the test water is sapropel. Using different amounts of sapropel (1, 2, 3, 4, 5, 6 g/dm3 and 0.1, 0.2, 0.4, 0.5, 0.6, 0.8 g/dm3) and different duration of contact (30, 60, 90, 120 and 150 minutes), the concentration of lead(II) ions in the test water after purification did not exceed the permissible values for drinking water (10 mg/dm3), so that the lowest sapropel content of 0.1 g/dm3 can be used for sorption. Lead(II) ions are most effectively removed when contact time is 30 min.
PL
Czynniki środowiskowe i ekonomiczne mają bardzo silny wpływ na rozwój technologiczny. Efektywność energetyczna jest jednym z najważniejszych tematów związanych z nowymi technologiami. Według prognoz długoterminowych zużycie energii elektrycznej z ok. 150 TWh obecnego zużycia, ma wzrosnąć do blisko 230 TWh około 2040 roku, co przekłada się na wzrost energii zużycia paliw oraz wzrost emisji szkodliwych zanieczyszczeń do atmosfery. Produkcja energii elektrycznej wiążę się z dużymi stratami w tym w postaci ciepła, które to można wykorzystać do produkcji chłodu przy użyciu chłodziarek adsorpcyjnych, które mogą być napędzane ciepłem niskotemperaturowym. Zastosowanie tego rodzaju systemów ma jeszcze jedną zaletę: umożliwia odsalanie wody morskiej do picia i wody użytkowej. W pracy przedstawiono przegląd zastosowania agregatów adsorpcyjnych w poligeneracji z wykorzystaniem ciepła odpadowego w niskiej temperaturze. Omówiono najnowsze systemy, ich parametry i warunki pracy. Przedstawiono również przegląd dostępnych technologii, materiałów i przykładowych instalacji badawczych w technice adsorpcyjnej.
EN
Environmental and economic factors have a very strong influence on technological development. Energy efficiency is one of the most important topics related to new technologies. According to long-term forecasts, the consumption of electricity from about 150 TWh of current consumption is to increase to nearly 230 TWh around 2040, which translates into an increase in the energy of fuel consumption and an increase in the emission of harmful pollutants into the atmosphere. The production of electricity is associated with large losses, including in the form of heat, which can be used to produce cold with the use of adsorption chillers, which can be driven by low-temperature heat. The use of such systems has another advantage: it allows desalination of seawater for drinking and drinking water. This paper gives an overview of the application of adsorption chillers in low-temperature waste heat polygeneration. The latest systems, their parameters and operating conditions were discussed. There is also a review of available technologies, materials and sample research installations in the adsorption technique.
EN
There is general agreement that primary pyrolysis products of end-of-life tyres should be valorised toimprove the economics of pyrolysis. In this work, tyre pyrolysis char (TPC) is produced in a pyrolysispilot plant designed and built at our home university. The produced TPC was upgraded to tyre-derivedactivated carbon (TDAC) by activation with CO2, and then characterised using stereological analysis(SA) and nitrogen adsorption at 77 K. SA showed that the grains of TPC and TDAC were quasi-spherical and slightly elongated with a 25% increase in the mean particle cross-section surface area forTDAC. The textural properties of TDAC demonstrated the BET and micropore surface areas of 259 and70 m2/g, respectively. Micropore volume and micropore surface area were 5.8 and 6.7 times higher forTDAC than TPC at2nm, respectively. Then-hexane adsorption was investigated using experimentsand modelling. Eight adsorption isotherms along with three error functions were tested to model theadsorption equilibrium. The optimum sets of isotherm parameters were chosen by comparing sum ofthe normalized errors. The analysis indicated that the Freundlich isotherm gave the best agreementwith the equilibrium experiments. In relation to different activated carbons, the adsorption capacityof TDAC forn-hexane is about 16.2 times higher than that of the worst reference material and 4.3times lower than that of the best reference material. In addition, stereological analysis showed thatactivation with CO2did not change the grain’s shape factors. However, a 25% increase in the meanparticle cross-section surface area for TDAC was observed.
EN
This paper aims to show the effect of activation method of tyre pyrolysis char (TPC) on adsorptionof bisphenol A (BPA) from aqueous solutions. The TPC was produced from end-of-life-tyres (ELT)feedstock in a pilot plant at 773 K. Activation was accomplished using two classical methods: physicalactivation with CO2and chemical activation with KOH. The two produced adsorbents had pores rangingfrom micro- to macropores. Distinct differences in the BET surface areas and pore volumes betweenthe adsorbents were displayed showing better performance of the chemically activated adsorbent foradsorption of BPA from water.The results of the kinetic studies showed that the adsorption of BPA followed pseudo-second-orderkinetic model. The Freundlich, Langmuir, Langmuir–Freundlich and Redlich–Peterson isotherm equa-tions were used for description of the adsorption data. The Langmuir–Freundlich isotherm model bestfits the experimental data for the BPA adsorption on both adsorbents. The Langmuir–Freundlichmonolayer adsorption capacity,qmLF, obtained for the CO2-activated tyre pyrolysis char (AP-CO2)and KOH-activated tyre pyrolysis char (AP-KOH) were 0.473 and 0.969 mmol g
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