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Tytuł:
Removal of Ni(II) ions from aqueous solutions using manganese oxide nanoparticles from buffelgrass, Cenchrus ciliaris L., as green adsorbent. Kinetics and thermodynamic studies
Autorzy:
Kiruba, Dunston Angeline
Muthukumaran, Karpagasundaram
Thamarai, Perumal
Powiązania:
https://bibliotekanauki.pl/articles/2057616.pdf
Data publikacji:
2022
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
Cenchrus ciliaris L.
ecosystem
Langmuir isotherm
Freundlich isotherm
heavy metals
ekosystem
izoterma Langmuira
izoterma Freundlicha
metale ciężkie
Opis:
Manganese oxide nanoparticles (MnONPs) synthesized from buffelgrass, Cenchrus ciliaris (L.), an invasive weed posing threats to ecosystems, are used in this study to remove nickel(II) ions from aqueous solutions. As a biosorbent, the synthesized MnONPs were put to the test. MnONPs were studied for their surface morphology and functional properties. A variety of adsorbent dosages and contact times were tested in batch experiments to see how they affected adsorption rates. At pH 6.0 and room temperature, MnONPs had an 87.1% removal efficiency for Ni(II) ions. Pseudo-second order correlations had a higher R2 value (0.988). In the Langmuir plot, a maximum adsorption capacity of 4.78 mg/g was observed. However, the experimental data fitted well with both Langmuir and Freundlich isotherm models (R2 = 0.99). Spontaneous and exothermic was the nature of the adsorption process. To remove heavy metal ions contaminants from aqueous solutions, these results suggested that MnONPs synthesized from buffelgrass extract could be used.
Źródło:
Environment Protection Engineering; 2022, 48, 1; 135--149
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:
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
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:
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:
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:
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:
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:
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:
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:
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:
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:
Removal of 2,4,6-trichlorophenol from aqueous solutions using agricultural waste as low-cost adsorbents
Autorzy:
Kuśmierek, K.
Świątkowski, A.
Dąbek, L.
Powiązania:
https://bibliotekanauki.pl/articles/207901.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
activated carbon
heavy metals
Langmuir isotherm
Freundlich models
węgiel aktywny
metale ciężkie
odpady rolnicze
izoterma Langmuira
Opis:
Agricultural waste products including sunflower seed hulls, pumpkin seed shells, walnut shells and peanut shells were used as low-cost adsorbents for the removal of 2,4,6-trichlorophenol (TCP) from aqueous solutions. The effects of adsorbent dosage, pH and ionic strength on the adsorption of TCP were investigated. The results showed that the adsorption of TCP was pH dependent and increased upon increasing the ionic strength of the solution. The adsorption kinetics was found to follow a pseudo-second order kinetics. The equilibrium adsorption data were fitted to the Langmuir, Freundlich and Sips isotherms and the best results were achieved with the Freundlich model. The desorption of TCP using deionized water, water/methanol mixture or 5% sodium hydroxide was also studied. The results suggest that the tested materials may be used as an effective adsorbents without any treatment or any other modification for removal of TCP from the aqueous medium.
Źródło:
Environment Protection Engineering; 2017, 43, 4; 149-163
0324-8828
Pojawia się w:
Environment Protection Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
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