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Tytuł:
Activated bio-carbons prepared by physical activation of residues after supercritical extractionof raw plants
Autorzy:
Bazan-Woźniak, Aleksandra
Pietrzak, Robert
Powiązania:
https://bibliotekanauki.pl/articles/110368.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
bio-sorbents
physical activation
toxic gas removal
adsorption from liquid phase
Langmuir and Freundlich isotherm
Opis:
A series of activated bio-carbons has been obtained by physical activation of residues after supercritical extraction of blackberries, raspberries and blackcurrants. The effects of different temperatures of activation and different starting materials on the physicochemical and sorption properties of the bio-carbon samples obtained were evaluated. The physicochemical properties of the activated bio-carbons were characterized by elementary analysis, low-temperature nitrogen sorption and Boehm titration. All materials were tested as adsorbents of pollutants from gas (nitrogen dioxide) and liquid (iodine, methylene blue) phase. The sorption properties of the activated bio-carbons were tested at 23°C. The materials obtained were activated bio-carbons of surface area ranging between 303 and 442 m2/g and showing basic character of the surface. The content of elemental carbon in the obtained samples was in the range of 73.4-82.1 wt. %. The maximum adsorption capacities of the materials towards nitrogen dioxide were 65 mg/g, methylene blue -207 mg/g, and iodine 1001 mg/g. According to the adsorption tests towards nitrogen dioxide, the sorption capacities of the adsorbents studied were increased if a mixture of nitrogen dioxide and air had a humidity of 70 %. The mechanism of methylene blue adsorption involved the formation of adsorptive multilayer. The most effective adsorbent of organic and inorganic pollutants proved to be the activated bio-carbon obtained from the residues after supercritical extraction of blackcurrants.
Źródło:
Physicochemical Problems of Mineral Processing; 2019, 55, 6; 1357-1365
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Adsorpcja ołowiu na modyfikowanym węglu aktywnym ROW 08 Supra
Adsorption of Lead on ROW 08 Supra Modified Activated Carbon
Autorzy:
Lach, J.
Okoniewska, E.
Ociepa-Kubicka, A.
Szymonik, A.
Powiązania:
https://bibliotekanauki.pl/articles/1818532.pdf
Data publikacji:
2015
Wydawca:
Politechnika Koszalińska. Wydawnictwo Uczelniane
Tematy:
adsorpcja
ołów
izoterma Langmuira
adsorption
lead
Langmuir isotherm
Opis:
The presented work is aimed at comparing two types of gaseous modification: conventional with the use of external source of energy (heat) and originally developed method with Joule heat generated during the flow of electrical current through a carbon bed. Conventional modification of ROW 08 Supra activated carbon was conducted in a rotary furnace in the atmosphere of (1) steam and carbon dioxide at temperature of 400 and 800°C and (2) air at the temperature of 400°C. The modification of activated carbon in the electric heating experimental system (referred to as SEOW) occurred in the process of heating of activated carbon during the flow of electric current through the carbon bed up to 400°C, followed by cooling down with the air or carbon dioxide. Both methods for modification of activated carbons allowed for increasing adsorption capacity towards ions Pb(II). The advantage of heating the activated carbon with the electric heating experimental system (SEOW) required far less energy than in case of conventional method (up to many fold). In case of modified carbon ROW 08 Supra, the increased adsorption efficiency was obtained for coals modified at 800°C and the carbon modified at 400°C with the participation of water vapor. As a result of modification of the SEOW carbons for all analyzed activated carbons, the adsorption percentage increased. Among all the modified activated carbon, the highest adsorption capacity has been given to carbon modified to SEOW through heating it to 400°C and air cooling as well. The results are described by the means of Freundlich and Langmuir isotherm. In order to determine the coefficients of Langmuir isotherm, five different rectilinear forms were used. Among the analyzed issues the best fit to the experimental results obtained for the I Langmuir isotherms (the highest values of the coefficients R2). The impact of pH and temperature on the effectiveness within the adsorption solution of Pb (II) was also analyzed. The most effective adsorption of lead from solutions of pH 2, 4, and 6 occurred at the highest pH, but the differences between the adsorption solution at pH 6 and pH 8 has been low. Within the adsorption from solutions having a pH of 2 a very little adsorption of lead was observed. Furthermore the size of adsorption of solutions at 20, 30 and 40°C was analyzed as well. What has been found is that through increasing the temperature the efficiency of the adsorption process within Pb (II) is raised.
Źródło:
Rocznik Ochrona Środowiska; 2015, Tom 17, cz. 1; 692-709
1506-218X
Pojawia się w:
Rocznik Ochrona Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Adsorpcja wybranych barwników z roztworów wodnych na nanoporowatych materiałach węglowych otrzymanych z prekursorów polimerowych
Adsorption of dyes from aqueous solutions on nanoporous carbon materials obtained from polymeric precursors
Autorzy:
Czubaszek, M.
Choma, J.
Powiązania:
https://bibliotekanauki.pl/articles/237872.pdf
Data publikacji:
2017
Wydawca:
Polskie Zrzeszenie Inżynierów i Techników Sanitarnych
Tematy:
porous carbon materials
adsorption isotherm
dyes
orange II
methyl orange
methylene blue
Langmuir's equation
Freundlich equation
Langmuir-Freundlich equation
iodine number
methylene number
porowate materiały węglowe
izoterma adsorpcji
barwniki
oranż II
oranż metylowy
błękit metylenowy
równanie Langmuira
równanie Freundlicha
równanie Langmuira-Freundlicha
liczba metylenowa
Opis:
Adsorption of orange II, methyl orange and methylene blue from aqueous solutions on three carbon materials was studied. The first material for studies was the microporous activated carbon obtained from sulfonated styrene- divinylbenzene resin (AC-SDVB), the second – ordered mesoporous carbon obtained from phenol-formaldehyde resin (OMC-PF) and the third – commercial micro-mesoporous activated carbon from Chemviron Carbon (AC-F400). Adsorption isotherms of the above-mentioned dyes on the carbon materials were studied under laboratory conditions at 25 C. The experimental data was described using the well-known Langmuir, Freundlich and Langmuir-Freundlich adsorption isotherm equations. On the basis of the correlation coefficient (R2) value, it was demonstrated that the Langmuir equation best described this data. The maximum adsorbed amounts for the three dyes were determined. The highest value was obtained for AC-SDVB: 625 mg/g for orange II and about 500 mg/g for methyl orange and methylene blue. These values were approximately five times higher than the maximum adsorption values for individual dyes on OMC-PF and AC-F400 (maximum adsorption values were about 100 mg/g). The difference in the effectiveness of dye adsorption on the carbon materials tested was the result of a much more developed porous structure of carbon AC-SDVB, compared to other two carbons. The specific surface area of AC-SDVB was 2 480 m2/g, 660 m2/g – for OMC-PF and 1 260 m2/g – for AC-F400. In addition, the values of standard characteristic numbers for activated carbons, methylene number and iodine number, were also evaluated. The highest value of both the methylene number, equal to 30 cm3, and the iodine number of 1 900 mg/g were obtained for AC-SDVB. In conclusion, some of the porous carbon materials obtained from polymers, characterized by excellent structural parameters, are particularly efficient in adsorption of dyes from aqueous solutions.
Badano adsorpcję trzech wybranych barwników organicznych (oranż II, oranż metylowy i błękit metylenowy) z roztworów wodnych na trzech materiałach węglowych. Pierwszym był mikroporowaty węgiel aktywny otrzymany z żywicy styrenowo-dwuwinylobenzenowej (AC-SDVB), drugim – uporządkowany węgiel mezoporowaty otrzymany z żywicy fenolowo-formaldehydowej (OMC-PF), a trzecim – handlowy mikro-mezoporowaty węgiel aktywnym firmy Chemviron Carbon (AC-F400). W warunkach laboratoryjnych wyznaczono doświadczalne izotermy adsorpcji tych barwników na węglach aktywnych w temperaturze 25C. Otrzymane dane doświadczalne opisano za pomocą znanych równań izoterm adsorpcji – Langmuira, Freundlicha oraz Langmuira-Freundlicha. Na podstawie wartości współczynnika korelacji (R2) stwierdzono, że najlepiej dane doświadczalne opisywało równanie izotermy Langmuira. Na podstawie otrzymanych izoterm adsorpcji wyznaczono maksymalne wartości adsorpcji poszczególnych barwników na badanych materiałach węglowych. Największą wartość adsorpcji uzyskano na węglu AC-SDVB – 625 mg/g (w przypadku oranżu II) oraz około 500 mg/g (w przypadku oranżu metylowego i błękitu metylenowego). Wartości te były około pięciokrotnie większe od maksymalnych adsorpcji poszczególnych barwników na węglach OMC-PF i AC-F400 (węgle te charakteryzowały sie maksymalną wartością adsorpcji każdego barwnika wynoszącą około 100 mg/g). Różnica w skuteczności adsorpcji barwników na badanych węglach była efektem znacznie lepiej rozwiniętej struktury porowatej węgla AC-SDVB, w porównaniu z pozostałymi węglami. Powierzchnia właściwa węgla AC-SDVB wynosiła 2480 m2/g, węgla OMC-PF – 660 m2/g, a węgla AC-F400 – 1260 m2/g. Ponadto wyznaczono wartości standardowych liczb charakteryzujących węgle aktywne – liczbę metylenową i liczbę jodową. Największą wartość zarówno liczby metylenowej (30 cm3), jak i liczby jodowej (1900 mg/g) otrzymano w przypadku węgla AC-SDVB. Badania wykazały, że niektóre porowate materiały węglowe otrzymane z polimerów, charakteryzujące się bardzo dobrymi parametrami struktury porowatej, wyjątkowo dobrze nadają się do adsorpcji barwników z roztworów wodnych.
Źródło:
Ochrona Środowiska; 2017, 39, 2; 3-10
1230-6169
Pojawia się w:
Ochrona Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Adsorption of reactive dyes and their mixtures on activated carbon. Kinetics, equilibrium and thermodynamic evaluation
Autorzy:
Kouhail, Meriem
Elahmadi, Zakia
Benayada, Abbes
Dewil, Raf
Powiązania:
https://bibliotekanauki.pl/articles/206912.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
adsorption efficiency
adsorption kinetics
Langmuir isotherm
reactive dye
COD
efektywność adsorpcji
kinetyka adsorpcji
izoterma Langmuira
barwnik reaktywny
ChZT
Opis:
The adsorption of three reactive dyes (Reactive Bezactiv Yellow (RBY), Reactive Bezactiv Blue (RBB) and Reactive Bezactiv (RBR)) on a commercially available activated carbon (CAC) has been evaluated. It was shown that CAC is capable to effectively remove these dyes from a solution. The adsorption increased with higher contact time, adsorbent dose, and initial dye concentration. The data indicated that the adsorption kinetics of dyes on CAC followed a pseudo-second order model. The adsorption isotherms followed the Langmuir isotherm model. Evaluation of thermodynamic parameters revealed that the adsorption process is endothermic for all dyes and spontaneous in a single system and became spontaneous in mixture systems at high temperature, expect RBY and RBB in the ternary mixture. Adsorption was higher for RBY, followed by RBB, and was lowest for RBR. The total adsorption efficiency was confirmed by chemical oxygen demand (COD) measurements.
Źródło:
Environment Protection Engineering; 2020, 46, 2; 5-24
0324-8828
Pojawia się w:
Environment Protection Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Adsorption of sodium/calcium poly(acrylic acid) salts on anatase: effect of the polyelectrolyte molecular weight and neutralization
Autorzy:
Jacquemet, Christian
Powiązania:
https://bibliotekanauki.pl/articles/1449765.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
adsorption
free energy
Langmuir isotherm
sodium-calcium poly(acrylic acid) salts
anatase
Opis:
Abstract: Interactions of poly(acrylic acid)s (PAAs) of two different molecular weights (Mw = 9,560 g×$mol^{-1}$ and 4,220 g×$mol^{-1}$) with surfaces of an untreated anatase $TiO_2$ were assessed through adsorption isotherm measurements. Those dispersants were tested under different sodium-calcium neutralization states (molar ratio $r = Ca^{2+}$ / $CO_{2-}$ varying from 0 to 0.35). Their behavior towards the $TiO_2$ surfaces can be described by the Langmuir adsorption model. For both polymers, surface coverage ($Γ_max$) evolves linearly with the molar ratio $r$. For a given r value, a lower surface coverage was observed with the polymer having the highest molecular weight. The free energy of adsorption ($/DeltaG_{ads}$) of PAAs was estimated from adsorption experiment data. This calculation indicates that sorption occurs spontaneously and is unlikely to be of chemical nature. The absolute values of $/DeltaG_{ads}$ are higher for the highest molecular weight polymers suggesting that they are more strongly adsorbed to anatase surfaces. The absolute values of $/DeltaG_{ads}$ per mole of sodium-calcium macromolecules are found to be lower than those calculated for their homologues 100% sodium neutralized suggesting that they are bound with the solid by a fewer number of segments.
Źródło:
Physicochemical Problems of Mineral Processing; 2020, 56, 1; 113-123
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Adsorption Studies of Nitrate by Geo-Physical Environment (Laterite soil) of the Study Area Bidar Urban & its Industrial Area, Karnataka State, India
Autorzy:
Shivasharanappa, ---
Padaki, S.
Kushtagi, S.
Powiązania:
https://bibliotekanauki.pl/articles/971327.pdf
Data publikacji:
2013
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Nitrate Adsorption
laterite
Batch Experiments
Freundlich isotherm
Langmuir isotherm
Opis:
In the present work, adsorption of Nitrate on Laterite soil has been studied using batch adsorption techniques. Main objectives of this study is to study the physical properties of Laterite soil, detection of Nitrate removal by adsorbent Laterite soil as a function of contact time, adsorbent dosage, pH, to study sorption kinetics, and to study isothermal pattern. The results of this study showed that the Optimum contact time, Optimum dosage and Optimum pH for adsorption of Nitrate on Laterite soil reached to equilibrium after 130 minutes, with removal efficiency of 68 %, 1400 mg as optimum dosage and at optimum pH of 6. The rate of adsorption of Nitrate obeys first order rate equation. The obtained results of the batch experiments are best fitted to Langmuir and Freundlich adsorption isotherms. From the experimental analysis it is concluded that Laterite soil shows good removal efficiency and hence can be used as adsorbent.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2013, 6; 66-76
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Applicability of different kinds of yeast biomass to lead removal from water
Możliwość wykorzystania różnych typów biomasy drożdży do usuwania ołowiu z wody
Autorzy:
Duda-Chodak, A.
Tarko, T.
Milotta, K.
Powiązania:
https://bibliotekanauki.pl/articles/1188062.pdf
Data publikacji:
2012
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie / Polskie Towarzystwo Magnezologiczne im. Prof. Juliana Aleksandrowicza
Tematy:
lead
toxicity
biosorption
waste treatment
yeasts
waste yeast
Langmuir isotherm
Opis:
Celem pracy była ocena możliwości wykorzystania biomasy drożdżowej do usuwania ołowiu z roztworów wodnych. Materiał badawczy stanowiły: drożdże piekarskie (BY), odpadowe drożdże browarnicze (WBY) oraz drożdże paszowe (FY), stanowiące łatwo dostępny odpad produkcyjny. Ilość biomasy drożdży (BY, WBY, FY) odpowiadającą 0,1 g suchej substancji zawieszano w 100 cm3 roztworu ołowiu (stężenie 200, 500 lub 1000 mg dm—3) i przeprowadzano biosorpcję przez 20, 40, 60, 90, 120, 240 i 300 minut. Stężenie ołowiu pozostałego w roztworze mierzono metodą adsorpcyjnej spektrometrii atomowej. Wielkość ładunku ołowiu usuniętego przez biomasę drożdży wyliczano na podstawie równania równowagi masowej biosorbenta, a wyniki dopasowywano do izotermy Langmuira. Testowane drożdże usuwały z roztworu ponad 90% ołowiu w ciągu 20 min procesu. Jednakże jedynie zastosowanie BY umożliwiało obniżenie poziomu Pb poniżej 1 mg dm—3 z roztworów o wyjściowym stężeniu 200 i 500 mg Pb dm—3. Wartość qmax oraz współczynnik powinowactwa b, wyznaczone dla drożdży piekarskich po 300 min biosorpcji, wynosify odpowiednio 1250 mg Pb g—1 s.s. i 0,363. Największą wydajność usuwania Pb wykazano stosując drożdże piekarskie (BY), gdy wyjściowe stężenie ołowiu wynosiło 500 mg dm—3. Stężenie równowagowe metalu po 300 min sorpcji wynosiło 0,66 mg dm—3, co odpowiada usunięciu przez biomasę drożdży piekarskich 99,86% ołowiu z roztworu.
Źródło:
Journal of Elementology; 2012, 17, 1; 7-18
1644-2296
Pojawia się w:
Journal of Elementology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Assessment of the sorption properties of materials proposed for the construction of insulation barriers
Autorzy:
Sobik-Szołtysek, J.
Bień, J.
Grosser, A.
Powiązania:
https://bibliotekanauki.pl/articles/207055.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
acid solution
batch methods
Insulation barriers
landfill site
Langmuir isotherm
Freundlich isotherm
mineral wastes
roztwor kwasu
metoda wsadowa
bariera izolacyjna
składowiska odpadów
izoterma Langmuira
izoterma Freundlicha
odpady mineralne
Opis:
Sorption properties of fine-grain mixtures of mineral waste proposed for construction of separation screens in landfill sites have been examined. The removal of heavy metals by the mixtures analysed was evaluated by the static batch method. It was found that they characterize by high ability to remove heavy metals at the level of over 99%, even with high contents of these elements. The sorption parameters have been determined based on the Langmuir and Freundlich isotherms. The alkaline character of some components of mixtures provides stabilization of pH, preventing removal of heavy metals to the environment in response to contact a barrier with acid solutions.
Źródło:
Environment Protection Engineering; 2016, 42, 1; 169-189
0324-8828
Pojawia się w:
Environment Protection Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dry Biosolids Reuse as Costless Biodegradable Adsorbent for Cadmium Removal from Water Systems
Autorzy:
Ammari, Tarek G.
Al-Hadidi, Majida
Al-Kharabsheh, Noor
Khater, Dima
Abu-Romman, Saeid
Powiązania:
https://bibliotekanauki.pl/articles/1838412.pdf
Data publikacji:
2021
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
adsorption
Cd-contaminated environment
untreated biosolids
intraparticle difusion model
Langmuir isotherm model
Opis:
The recycling of untreated dry biosolids, as costless biodegradable adsorbent for the removal of cadmium from aqueous phase was characterized. The adsorption of cadmium was reported to depend on initial pH, adsorbent dose, agitation time, and initial Cd concentration. The results of the batch experiments revealed that the maximum adsorption capacity of the untreated dry biosolids was 39.22 mg g-1 under optimum operating conditions (i.e. pH: 5, adsorbent dose: 2 g l-1, contact time: 16h). Adsorption reaches equilibrium after 16h, which can be attributed to both external surface adsorption (R2 = 0.86) and intraparticle dif usion (R2 = 0.98). The Langmuir isotherm model best described cadmium adsorption (R2 = 0.99) and the pseudo-second-order kinetic model was obeyed, suggesting that the mechanism involved was chemisorption. Biodegradability would make the recovery of adsorbed Cd an environmentally friendly process. Comparing the obtained findings with the related published results, it can be concluded that treating biosolids might be an unnecessary and costly procedure for recycling biosolids as an adsorbent for cadmium.
Źródło:
Journal of Ecological Engineering; 2021, 22, 5; 1-12
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Enhancing adsorption capacity of clay and application in dye removal from waste water
Autorzy:
Ogunmodede, O. T.
Adebayo, O. L
Ojo, A. A.
Powiązania:
https://bibliotekanauki.pl/articles/412039.pdf
Data publikacji:
2014
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
snail shell
methylene blue
natural clay
langmuir
freundlich
temkin
Halsey and Harkins-Jura isotherm equations
Opis:
Natural clay has been considered as a potential absorbent for removing pollutants from water and waste water. Nonetheless, the effective application of clay for water treatment is limited due to small surface area and presence of net negative surface charge, leading to it low adsorption capacity. The absorption capacity was boosted via intercalation of CaO derived from snail shell (SS). The methylene blue sorption potential, PZC, and the surface area of unmodified clay sample were substantially enhanced by the intercalation process. The process of sorption of MB from solution was analyzed using five different isotherm models (Langmuir, Freundlich, Temkin, Harkins-Jura, and Halsey isotherm equations). The value of the Langmuir monolayer sorption capacity qm (mg/g) increased from 50.12 to 88.71, PZC values increased from 4.50 to 7.40, and the surface area (m2/g) value increased from 27 m2/g to 123 m2/g after the intercalation process. The experimental data were fitted into two kinetic models: Lagergren pseudo-first order and the chemisorptions pseudo-second order. It was observed that chemisorptions pseudo-second order kinetic model described the sorption process with high coefficients of determination (r2) better than pseudo first other kinetic models. The modification caused no change in the clay surficial microstructure but increased the lattice spacing of the clay framework.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2014, 20, 1; 35-51
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation of the corrosion inhibition effect of Ipomoea batatas leaves extract on mild steel in sulphuric acid
Autorzy:
Udowo, V. M.
Uwah, I. E.
Magu, T. O.
Thomas, U. E.
Powiązania:
https://bibliotekanauki.pl/articles/1178378.pdf
Data publikacji:
2017
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Ethanolic extract of Ipomoea batatas leaves (EEIBL)
Gasometry
Gravimetry
Ipomoea batatas
Langmuir Isotherm
Opis:
The inhibition of mild steel corrosion in 1 M sulphuric acid media by ethanolic extracts of Ipomoea batatas was investigated using the gravimetric and gasometric methods. The extracts recorded an inhibition efficiency of 61.1 % and 52.6 % at room temperature for the gravimetry and the gasometry respectively. The inhibition process was initiated by the physical adsorption of the inhibitor extracts to the metal surface and the data obtained fitted very well into the Langmuir adsorption isotherm.
Źródło:
World Scientific News; 2017, 77, 2; 354-361
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ferric hydroxide-based media for removal of toxic arsenic species. Kinetic, equilibrium and thermodynamic studies
Autorzy:
Szlachta, M.
Wójtowicz, P.
Powiązania:
https://bibliotekanauki.pl/articles/207931.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
Freundlich isotherm
Langmuir isotherm
arsenic
adsorption
sewage
izoterma Freundlicha
izoterma Langmuira
arsen
adsorpcja
ścieki
Opis:
Adsorption studies were conducted to assess the feasibility of ferric hydroxide-based material for treatment of highly arsenic-contaminated effluents. The experiments were performed in a batch adsorption regime using a synthetic aqueous solution. The contact time between arsenic ions and the adsorbent, initial concentration of arsenic in treated solution, temperature of solution and adsorbent dose had a significant effect on the adsorption performance in the system. Both the mechanism of the process involved and the rate of As(III) and As(V) adsorption were analyzed based on pseudo-firstand pseudo-second order kinetic models. The adsorption data at constant temperature were described by the Langmuir and Freundlich isotherm equation, and the theoretical adsorption capacity of ferric hydroxide was determined to be 43.75 mg/g and 44.04 mg/g for arsenic(III) and (V), respectively. The estimated thermodynamic parameters, including changes in free energy, enthalpy and entropy, revealed that the adsorption is spontaneous and endothermic under applied experimental conditions.
Źródło:
Environment Protection Engineering; 2018, 44, 4; 117-129
0324-8828
Pojawia się w:
Environment Protection Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hydrocarbons removal from underground coal gasification water by organic adsorbents
Autorzy:
Lutynski, M.
Suponik, T.
Powiązania:
https://bibliotekanauki.pl/articles/110448.pdf
Data publikacji:
2014
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
underground coal gasification
permeable reactive barrier
Langmuir adsorption isotherm
Opis:
The main problems in the case of the undergorund coal gasificiation process is the possible pollution of surrounding aquifers. The underground gasification cavity is a source of both gaseous and liquid pollutants and these are mainly aromatic hydrocarbons, phenols, heavy metals and others. In order to prevent underground water from pollution a permeable reactive barrier was proposed. The filling was granulated activated carbon and SPILL-SORB (peat) – two commonly available sorbents adequate for hydrocarbons removal. The wastewater (synthetic solution which simulated groundwater contaminated with the UCG products) was prepared by mixing distilled water with desired amounts of substances such as phenols, benzene, toluene, xylene, naphthalene etc. Batch tests were performed in order to measure sorption of phenols and benzene from the post-UCG water on the mentioned sorbents. Experimental results were fitted with linear and non-linear Freundlich and Langmuir isotherm models. The obtained data showed that removal of phenols and benzene in case of GAC was much more efficient. However, sorption was lower than in the case of literature data and can be explained by complex composition of the solution and pre-treatment of the samples. The Langmuir model gave a better fit in the case of GAC, whereas Freundlich isotherm model was matching the data better in case of SPILL-SORB.
Źródło:
Physicochemical Problems of Mineral Processing; 2014, 50, 1; 289-298
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of coal particle size on coal adsorption and desorption characteristics
Wpływ wielkości ziaren węgla na charakterystyki adsorpcji i desorpcji na węglu
Autorzy:
Zhang, L.
Aziz, N.
Ren, T.
Nemcik, J.
Tu, S.
Powiązania:
https://bibliotekanauki.pl/articles/219328.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
adsorpcja na węglu
desorpcja na węglu
wymiary ziaren węgla
izoterma
objętość Langmuira
coal adsorption
desorption
coal particle size
isotherm
Langmuir volume
Opis:
Accurate testing coal isotherm can play a significant role in the areas of coal seam gas drainage, outburst control, CO2 geo-sequestration, coalbed methane (CBM) and enhanced coalbed methane recovery (ECBM) etc. The effect of particle size on the CO2 and CH4 sorption capacity of bituminous coal from Illawarra, Australia was investigated at 35°C and at pressure up to 4 MPa. A unique indirect gravimetric apparatus was used to measure the gas adsorption and desorption isotherms of coal of different particle sizes ranging from around 150 urn to 16 mm. Langmuir model was used to analysis the experimental results of all gases. Coal particle size was found to have an apparent effect on the coal ash content and helium density results. Coal with larger particle size had higher ash content and higher helium density. The sorption isotherm was found to be highly sensitive with helium density of coal which was determined in the procedure of testing the void volume of sample cell. Hence, coal particle size had a significant influence on the coal sorption characteristics including sorption capacity and desorption hysteresis for CO2 and CH4, especially calculated with dry basis of coal. In this study, the 150-212 um (150 um) coal samples achieved higher sorption capacity and followed by 2.36-3.35 mm (2.4 mm), 8-9.5 mm (8 mm) and 16-19 mm (16 mm) particle size samples. However, the differences between different coal particles were getting smaller when the sorption isotherms are calculated with dry ash free basis. Test with 150 um coal samples were also found to have relatively smaller desorption hysteresis compared with the other larger particle size samples. The different results including adsorption/desorption isotherm, Langmuir parameters and coal hysteresis were all analysed with the CO2 and CH4 gases.
Dokładne zbadanie izoterm sorpcji na węglu odgrywa kluczową rolę w takich dziedzinach jak odgazowanie pokładów węgla, zapobieganie wybuchom, sekwestracja geologiczna CO2, odzysk metanu ze złoża. Wpływ wielkości ziaren na pojemność sorpcyjną bitumicznego węgla z Illawara (Australia) względem CO2 i CH4 zbadano w temperaturze 35°C przy ciśnieniu do 4 MPa. Wykorzystano oryginalną aparaturę do badań grawimetrycznych do zmierzenia izoterm adsorpcji i desorpcji na węglu w którym rozmiar ziaren wahał się od 150 μm do 16 mm. Analizę wyników doświadczalnych dla wszystkich gazów przeprowadzono w oparciu o model Langmuira. Stwierdzono, że rozmiary ziaren węglowych w znacznym stopniu warunkują zawartość popiołu i gęstość helową. Węgiel grubiej uziarniony charakteryzował się wyższą zawartością popiołu i większą gęstością helową. Wykazano, że izoterma sorpcji wykazuje wysoką wrażliwość na zmiany gęstości helowej, co stwierdzono na podstawie badania martwej przestrzeni ampułki w której umieszczono próbkę. Wnioskować stąd można, że rozmiar ziaren węgla w dużym stopniu wpływa na charakterystyki sorpcyjne węgla, w tym także na chłonność sorpcyjną i histerezy desorpcji dla CO2 i CH4, zwłaszcza w badaniach na węglu suchym. W trakcie badań próbki węgla z ziarnami o wymiarach 150-212 μm (150 μm) wykazywały wyższą chłonność sorpcyjną, w dalszej kolejności plasowały się próbki o wymiarach ziaren: 2.36-3.35 mm (2.4 mm), 8-9.5 mm (8 mm) i 16-19 (16 mm). Jednakże różnice pomiędzy różnymi ziarnami węgla stawały się mniej wyraźne gdy izotermy sorpcji obliczane były w odniesieniu do próbki suchej, pozbawionej popiołu. Badania próbek o wymiarach ziaren 150 μm wykazały, że w ich przypadku histereza desorpcji jest stosunkowo mniejsza w porównaniu z próbkami gruboziarnistymi. Wszystkie wyniki: izotermy adsorpcji i desorpcji, parametry Langmuira oraz histerezy węgla badano przy użyciu dwóch gazów: CO2 i CH4.
Źródło:
Archives of Mining Sciences; 2014, 59, 3; 807-820
0860-7001
Pojawia się w:
Archives of Mining Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigation of nickel adsorption onto low Jordanian zeolite dose: efficiency and Langmuir – Freundlich behaviour
Autorzy:
Al-Ghazawi, Ziad
Qasaimeh, Ahmad
Al-Bataina, Bilal
Powiązania:
https://bibliotekanauki.pl/articles/1841957.pdf
Data publikacji:
2021
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
batch reactor
Freundlich
isotherm
Langmuir
low dose
metals
nickel
wastewater
zeolite
Opis:
In this work, nickel adsorption onto low Jordanian zeolite dose is being investigated. Natural zeolite doses were stirred continuously with nickel solutions in batch reactors at 180 RPM for 24 hours, where the temperature was set to 20°C. The pH was initially 4.5 and reached 5.2 at equilibrium. The removal efficiency of nickel reaches maximum value when the initial nickel concentration is around 1 ppm and then tends to decrease when the initial nickel concentration increases above 1 ppm. The optimal nickel removal reaches 65% when the initial nickel concentration is 1 ppm and the zeolite dose is 26 mg∙dm–3. This study investigates the behaviour of nickel removal and modelling isotherms below and above this critical peak point. At this level of zeolite dose, the adsorption does not follow either Freundlich or Langmuir isotherms, but rather, it follows Freundlich for the data plot just below the peak point with the highest coefficient of determination (R2) equals (0.98) when the zeolite dose is (26 mg∙dm–3), whereas it follows Langmuir for the data plot just above the peak point with the highest coefficient of determination (R2) equals (0.99) when the zeolite dose is (10 mg∙dm–3). These findings clarify the theory behind each isotherm and can be used to find new information for efficient treatment techniques.
Źródło:
Journal of Water and Land Development; 2021, 50; 150-157
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł
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