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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:
Thermodynamics and adsorption studies of dye (rhodamine-b) onto natural diatomite
Autorzy:
Koyuncu, M.
Kul, A. R.
Powiązania:
https://bibliotekanauki.pl/articles/110287.pdf
Data publikacji:
2014
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
diatomite
rhodamine B
adsorption
thermodynamics
Langmuir isotherm
Freundlich isotherm
Opis:
Thermodynamics and adsorption studies were conducted with a dye of rhodamine-B on natural diatomite. Adsorption of the dye was investigated with an initial dye concentration at pH 8±0.2, 303, 313 and 323 K. The adsorption experiments were carried out isothermally at three different temperatures. The Langmuir and Freundlich isotherm models were used to describe the equilibrium data and the results were discussed in details. The kinetic data agreed with the pseudo-first order model with rate constants (k2) in the range of 3.05–1.59.10–1 g/mg min. The thermodynamic parameters such as standard free energy, entropy change and enthalpy were calculated for natural diatomite. These values showed that adsorption of rhodamine-B on natural diatomite was a spontaneous and endothermic process.
Źródło:
Physicochemical Problems of Mineral Processing; 2014, 50, 2; 631-643
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:
Removal of Heavy Metal by Ion Exchange Using Bentonite Clay
Autorzy:
Hussain, Shaymaa Talib
Ali, Seroor Atalah Khaleefa
Powiązania:
https://bibliotekanauki.pl/articles/1839579.pdf
Data publikacji:
2021
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
bentonite
lead ion
copper ion
adsorption
wastewater
Freundlich isotherm
Langmuir isotherm
Opis:
Bentonite clay was utilized in this research as adsorbent element to remove the lead and copper ions from wastewater. Series of tests were performed at multiple parameters, such as pH solution, initial concentration of lead and copper ions, adsorbent mass, and contact time. The greatest removal was attained at pH 5, adsorbent weight of 0.5 g, initial heavy metal concentration of 10 mg/l, and a contact time of 60 minutes. The results revealed that bentonite clay is suitable in the removal of metal ions from polluted water. The ion exchange rate of lead was faster than that of copper. The isotherm for the adsorption of the lead and copper ions on bentonite clay was confirmed by the Freundlich and Langmuir isotherms which offered good consequences. The results indicated that bentonite was utilized as an efficient ion exchange element for the removal of heavy metal ions from polluted water. Fourier Transformed Infrared Spectrophotometer (FTIR) images of bentonite clay before and after adsorption showed the imbibition of metal ions by bentonite clay.
Źródło:
Journal of Ecological Engineering; 2021, 22, 1; 104-111
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simultaneous removal of NH4+ and PO43- from simulated reclaimed waters by modified natural zeolite. Preparation, characterization and thermodynamics
Autorzy:
Alshameri, A.
He, H.
Dawood, A. S.
Zhu, J.
Powiązania:
https://bibliotekanauki.pl/articles/207387.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
Langmuir isotherm
struvite crystallization
nitrogen
izoterma Langmuira
krystalizacja struwitu
azot
Opis:
Natural zeolite was modified by NaCl, AlCl3 and thermal treatment for the removal of NH4+ and PO43− ions. The characteristics of the modified zeolite (AlZ) and its mechanism for the NH4 + and PO43− removal were studied and compared. The results showed that the surface area and the Na+ and Al3+ content increased whereas the content of Ca2+, K+ and Mg2+ decreased after zeolite modification. On natural zeolite when activated with the 1 M NaCl and 10 cm3 /g of pillaring dosage, high adsorption efficiencies for the NH4 + (97.80%) PO43− (98.60%) were obtained. The results of various analyses indicated that the Na+ exchange is the main mechanism for NH4 + removal whereas the adsorption mechanism for PO43− followed the complexation with Al–OH groups present in the AlZ. In addition, the kinetics study showed that the adsorption of NH4+ and PO43− followed pseudo-second order model while the adsorption isotherm of NH4 + and PO43− is consistent with the Langmuir isotherm model. Moreover, the Gibbs free energy change for the simultaneous removal of the ions indicates that NH4 + is adsorbed faster compared to PO43−. The simultaneous removal of NH4 + and PO43− by AlZ adsorbent is cost effective in water treatment at low ion concentrations.
Źródło:
Environment Protection Engineering; 2017, 43, 4; 73-92
0324-8828
Pojawia się w:
Environment Protection Engineering
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:
Uptake of phosphates from water solutions on metallurgical sludge
Autorzy:
Kostura, Bruno
Huczala, Radim
Klika, Zdeněk
Ritz, Michal
Bartoňová, Lucie
Matýsek, Dalibor
Powiązania:
https://bibliotekanauki.pl/articles/2032862.pdf
Data publikacji:
2021
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
phosphates
heavy metals
Langmuir isotherm
Freundlich isotherm
fosforany
metale ciężkie
izoterma Langmuira
izoterma Freundlicha
Opis:
Steel-making dust slurry (SS) and convertor dust slurry (CS) were tested for uptake of phosphates from aqueous solutions. The adsorption of phosphates on SS and CS corresponded well with both Langmuir and Freundlich adsorption isotherms, which indicated the combination of physical and chemical processes. The maximum adsorbed amount of phosphates on both dust slurry samples was ca. 11 mg P/g. The study evaluates also the effect of acidic leaching on the retention characteristics of both dust slurry samples. From the slurry samples prepared by acidic leaching, the leached convertor dust slurry (CSL) was the only sample capable to retain phosphates. To reveal the retention mechanisms of phosphates, the original and leached dust slurry samples were analyzed by IR and Raman spectroscopy. Co-precipitation of Ca and Fe phosphates, or surface complexation of phosphates were evaluated as the retention mechanisms of CS and CSL while the retention of phosphates by zincite in the case of SS is probably based on their adsorption.
Źródło:
Environment Protection Engineering; 2021, 47, 3; 37-51
0324-8828
Pojawia się w:
Environment Protection Engineering
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:
Removal of Cr(VI) using a novel adsorbent modification. Ultrasonic method with apricot kernel shells
Autorzy:
Kalipci, E.
Namal, O. O.
Powiązania:
https://bibliotekanauki.pl/articles/207440.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
adsorption
isotherms
ultrasonics
Langmuir adsorption
Langmuir isotherm
adsorpcja
izotermy
ultradźwięki
adsorpcja Langmuira
izoterma Langmuira
Opis:
Raw apricot kernel shells (AKS) and ultrasound-modified apricot kernel shells were used as adsorbents for the removal of Cr(VI) from aqueous solutions. For raw and modified AKS, the experimental data well fitted to the Langmuir isotherm and adsorption kinetics was suited to pseudo-second order kinetic model indicating chemisorption as the rate-limiting step. For raw and modified AKS, maximum adsorption capacities obtained from the Langmuir adsorption model were 6.5 mg/g and 9.9 mg/g, respectively. Maximum Cr(VI) adsorption was obtained at a pH 2 and optimum stirring speed was determined as 250 rpm. After ultrasound modification, an increase for Cr(VI) adsorption was observed. Raw AKS as low-cost natural biomaterial can be preferred for the removal of Cr(VI) when compared to other adsorbents. Ultrasonic modification can be used to improve the efficiency of Cr(VI) removal.
Źródło:
Environment Protection Engineering; 2018, 44, 3; 79-93
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:
Surface modification of fly ash spheroidal particles and their application in the adsorption of phosphorus and chromium(VI) from single and competitive solute systems
Autorzy:
Chen, Chen
Cheng, Ting
Zhang, Xiao
Zhang, Minte
Lv, Ruiyang
Powiązania:
https://bibliotekanauki.pl/articles/2032957.pdf
Data publikacji:
2021
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
fly ash
Langmuir isotherm
adsorption phosphorus
popiół lotny
izoterma Langmuira
adsorpcja fosforu
Opis:
This work focuses on the surface modification of fly ash spheroidal particles and their application in phosphorus and chromium(VI) adsorption. The results show that through surface modification, amorphous silica-alumina gels precipitated on the spheroidal particle surface (by which the microsurface area of the reaction products is effectively enlarged) and the surface zeta potential was changed to fit for adsorbing anions. During the adsorption experiment (single and competitive solute systems), chromium(VI) was easier to adsorb. The surface zeta potential and the existence of competitive ions should be recognized as two important factors affecting adsorption efficiency. A higher temperature could improve the adsorption efficiencies of the two solute systems. The fitting results of the pseudo-second-order model (single and competitive solute systems) show better agreement than those of the pseudo-first-order model at every temperature. The Langmuir adsorption isotherm equation can better simulate the adsorption process in single solute sy039stems, but only the chromium(VI) adsorption process can be fitted by the competitive Langmuir adsorption isotherm in competitive solute systems.
Źródło:
Environment Protection Engineering; 2020, 46, 3; 39-59
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:
Phosphorus sorption capacity of different types of opoka
Zdolnosc wchlaniania fosforu przez rozne rodzaje opoki
Autorzy:
Cucarella, V.
Zaleski, T.
Mazurek, R.
Powiązania:
https://bibliotekanauki.pl/articles/81895.pdf
Data publikacji:
2007
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
Tematy:
calcium
Freundlich adsorption model
Freundlich isotherm
langmuir isotherm
opoka
phosphorus removal
silica
sorption
phosphorus sorption
Opis:
The bedrock opoka has been lately reported as an appropriate reactive media for onsite wastewater treatment systems due to its high phosphorus (P) sorption capacity. However, variations on its chemical composition may affect its reactivity with P, therefore leading to a variable P removal effi ciency. In this paper, the P-sorption capacity of three different types of opoka from the region of Miechów, Poland, is reported. According to the silica and carbonate content, opoka samples were classifi ed as light--weight and heavy-weight opoka. When heated over 900°C, opoka showed a very high P-sorption capacity that was well correlated to its Ca content. P-sorption isotherms from batch experiments with an artifi cial P solution were plotted and fi tted to the Langmuir and Freundlich adsorption models. The Freundlich isotherm appeared to model better the P-sorption of light opoka and the Langmuir isotherm of heavy opoka, suggesting different dominating mechanisms of P-sorption by light and heavy opoka.
Według ostatnich badań opoka jest uważana za sorbent, który ze względu na wysoką zdolność wiązania fosforu, może mieć zastosowanie w przydomowych oczyszczalniach ścieków. Jednakże różnorodność składu chemicznego opoki wpływa na intensywność wiązania P i prowadzi do różnej efektywności procesu oczyszczania ścieków. W pracy przedstawiono zdolność wiązania P przez trzy rodzaje opok pobranych w rejonie Miechowa (woj. małopolskie). Na podstawie zawartości krzemionki i węglanów próbki zostały podzielone na opokę lekką i ciężką. Po wypaleniu w temperaturze ponad 900°C opoka charakteryzowała się bardzo wysoką zdolnością wiązania P, silnie skorelowaną z zawartością Ca. Krzywe sorpcji P, otrzymane podczas doświadczenia ze sztucznie sporządzonym roztworem zawierającym rozpuszczony P, porównano z modelami absorpcji opracowanymi przez Langmuira i Freundlicha. Izoterma Freundlicha była bardziej zbliżona do krzywej wiązania P przez opokę lekką, z kolei model Langmuira okazał się bliższy krzywej sorpcji opoki ciężkiej.
Źródło:
Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation; 2007, 38; 11-18
0208-5771
Pojawia się w:
Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Usuwanie i odzysk miedzi z roztworów wodnych przy użyciu wybranych syntetycznych żywic jonowymiennych (część II)
Cooper removal and recovery from aqueous solutions by using selected synthetic ion exchange resins (part II)
Autorzy:
Bożęcka, Agnieszka
Orlof-Naturalna, Monika
Powiązania:
https://bibliotekanauki.pl/articles/1841493.pdf
Data publikacji:
2020
Wydawca:
Polskie Towarzystwo Przeróbki Kopalin
Tematy:
copper
ion exchange resins
Langmuir isotherm
Freundlich isotherm
miedź
żywice jonowymienne
izoterma Langmuira
izoterma Freundlicha
Opis:
In paper the possibility of Cu2+ ions removing from aqueous solutions on selected synthetic ion exchange resins (Purolite S 910, S 930, S 940, S 950, C 160) was studied. These processes were described by the Langmuir and Freundlich adsorption models. It was found that the process of Cu2+ ions removing on S 910 and S 930 ion exchangers were the best described by linear equation form of Langmuir isotherm. The fit quality of the Freundlich isotherm is the best for S 940, C 160 and S 950 ion exchangers, which is confirmed by the obtained values of correlation coefficients R. The highest value of the maximum sorption capacity (about 69 mg/g) was obtained for C 160 cation exchange resin with sulfonic groups. For others ion exchange resins the monolayer capacity was decreasing in following order S 940 > S 930 > S 950 > S 910. The S 940 and S 930 ion exchangers were characterized by the highest affinity for Cu2+ ions. The amidoxime polyacrylic chelating resin S 910 was the least efficient. The differences in the affinity of the studied resins towards to Cu2+ ions can be explained by their different chemical or physical structure and particles size. In case of the studied ion exchange resins, the 1/n parameter values of the Freundlich isotherm were in range of 0.21–0.32. Therefore, it can be concluded that energy heterogeneity of the studied sorption system and intensity of Cu2+ ion removal on above ion exchangers are moderate. The K parameter value of the Freundlich equation was also highest for ion exchangers S 930 and S 940.
Wykorzystanie modeli izoterm adsorpcji do opisu procesów usuwania jonów Cu2+ z roztworów wodnych na wybranych syntetycz¬nych żywicach jonowymiennych W pracy zbadano możliwość usuwania jonów Cu2+ z roztworów wodnych za pomocą syntetycznych żywic jonowymiennych firmy Purolite. Do badań wytypowano jonity chelatujące S 910, S 930, S 940, S 950 oraz kationit C 160. Badane procesy opisano za pomocą modelu adsorpcji Langmuira i Freundlicha. Stwierdzono, że liniowa forma równania izotermy Langmuira najlepiej opisuje proces usuwania jonów Cu2+ na jonicie S 910 i S 930. Jakość dopasowania izotermy Freundlicha jest najlepsza w przypadku jonitów S 940; C 160 i S 950 o czym świadczą uzyskane war-tości współczynników korelacji R. Największą wartość maksymalnej pojemności sorpcyjnej (ok. 69 mg/g) uzyskano dla kationitu C 160 z grupami sulfonowymi. Pojemność monowarstwy wyznaczona dla pozostałych jonitów chelatujących malała w szeregu S 940 > S 930 > S 950 > S 910. Największym powinowactwem do jonów Cu2+ cechował się jonit S 940 i S 930. Najmniej skuteczna okazała się amidoksymowa poliakrylowa żywica chelatująca S 910. Zaistniałe różnice w powinowactwie badanych żywic względem jonów Cu2+ można tłumaczyć ich odmienną budową chemiczną, strukturą fizyczną oraz wielkością cząstek. W przypadku badanych żywic jonowymiennych, wartości stałej 1/n izotermy Freundlicha znajdowały się w zakresie 0,21–0,32. Moż¬na zatem stwierdzić, że niejednorodność energetyczna badanego układu sorpcyjnego i intensywność procesu usuwania jonów Cu2+ na ww. jonitach jest umiarkowana. Wartość parametru K równania Freundlicha była najwyższa również dla jonitów S 930 i S 940.
Źródło:
Inżynieria Mineralna; 2020, 2, 2; 15-20
1640-4920
Pojawia się w:
Inżynieria Mineralna
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
Wyświetlanie 1-15 z 33

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