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1
Content available Removal of Ni(II) ions from aqueous solutions using manganese oxide nanoparticles from buffelgrass, Cenchrus ciliaris L., as green adsorbent. Kinetics and thermodynamic studies
Kiruba Dunston Angeline, Muthukumaran Karpagasundaram, Thamarai Perumal
Environment Protection Engineering
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2022
|
Vol. 48, nr 1
135--149
EN
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.
2
Content available Removal of Heavy Metal by Ion Exchange Using Bentonite Clay
Hussain Shaymaa Talib, Ali Seroor Atalah Khaleefa
Journal of Ecological Engineering
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2021
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Vol. 22, nr 1
104--111
EN
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.
3
Content available Uptake of phosphates from water solutions on metallurgical sludge
Kostura Bruno, Huczala Radim, Klika Zdeněk, Ritz Michal, Bartoňová Lucie, Matýsek Dalibor
Environment Protection Engineering
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2021
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Vol. 47, nr 3
37--51
EN
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.
4
Content available Cooper removal and recovery from aqueous solutions by using selected synthetic ion exchange resins (part II)
Bożęcka Agnieszka, Orlof-Naturalna Monika
Inżynieria Mineralna
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2020
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no. 2, vol. 2
15--20
EN
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.
PL
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.
5
Content available Application of organic waste for adsorption of Zn(II) and Cd(II) ions
Bakalár Tomáš, Pavolová Henrieta
Environment Protection Engineering
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2019
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Vol. 45, nr 2
35--54
EN
Biosorption of Zn(II) and Cd(II) ions from aqueous solutions onto organic waste – orange peel, hazelnut shell, and walnut shell was studied using batch adsorption experiments. In the biosorption studies, equilibrium metal ion concentration was determined. Experimental data obtained were analysed in terms of Freundlich, Langmuir, Temkin, Dubinin–Radushkevich, Redlich–Peterson, Sips, Toth, and Khan isotherms. The results of the study showed that orange peel, hazelnut shell, and walnut shell can be adequately used as low-cost alternatives for the removal of Zn(II) and Cd(II) ions from aqueous solutions with maximum sorption capacities of 15.51 and 19.8 mg/g, 11.55 and 16.65 mg/g, and 26.60 and 21.10 mg/g, respectively. The highest removal efficiency of Zn(II) and Cd(II) ions was obtained for hazelnut shells. The process was fast and about 90% of metal ions were removed by all the studied biosorbents. The sorption process was possibly chemisorption occurring on a heterogeneous surface.
6
Content available Ferric hydroxide-based media for removal of toxic arsenic species. Kinetic, equilibrium and thermodynamic studies
Szlachta M., Wójtowicz P.
Environment Protection Engineering
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2018
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Vol. 44, nr 4
117--129
EN
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.
7
Content available Sorption process of Acid Yellow 36 on sludge-based activated carbon
Pieczykolan B., Płonka I.
Proceedings of ECOpole
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2016
|
Vol. 10, No. 1
67--73
EN
The study of sorption of dye Acid Yellow 36 on SAC (sludge-based activated carbon) was conducted. For this purpose, anaerobically digested and dewatered sewage sludge was dried at 105ºC to constant weight. Next this sludge was milled to a particle with a diameter of 0.5-1.0 mm and subjected to chemical activation by hydrogen peroxide. After oxidation process the sludge was subjected to thermal transformation in a muffle furnace at 600ºC. In this way obtained a powder activated carbon based on activated sludge (so-called SAC). Based on the results of the study the most favorable parameters of sorption process was achieved as follows: pH value equaled to 2.5 and reaction time equaled to 30 minutes. The linearized forms of Freundlich and Langmuir isotherms showed that the highest value of correlation factor was obtained in the case of Langmuir model. However, in this case, the negative value of constant isotherm was achieved. Therefore, it can be assumed that more accurately in this case is the Freundlich model or other model which was not examined during that studies.
PL
Przeprowadzono badania sorpcji barwnika Acid Yellow 36 z użyciem węgla aktywnego bazującego na osadzie ściekowym. W tym celu ustabilizowany beztlenowo i odwodniony osad czynny wysuszono w 105ºC do stałej masy. Następnie osad ten zmielono do ziaren o średnicy 0,5-1,0 mm i poddano chemicznej aktywacji za pomocą nadtlenku wodoru. Po tym procesie osad spalono w piecu muflowym w 600ºC, uzyskując w ten sposób pylisty węgiel aktywny bazujący na osadzie czynnym (tzw. SAC - czyli „sludge-based activated carbon”). Dla tak spreparowanego węgla aktywnego przeprowadzono badania procesu sorpcji statycznej względem barwnika Acid Yellow 36. Na podstawie przeprowadzonych eksperymentów stwierdzono, że najkorzystniejsza wartość pH wynosi 2,5, a czas kontaktu jest równy 30 minut. Natomiast bazując na graficznych formach zlinearyzowanych modelów sorpcji według Langmuira i Freundlicha, stwierdzono, że największą wartość współczynnika korelacji odnotowano w przypadku zlinearyzowanej formy równania Langmuira. Jednakże w tym przypadku uzyskano ujemne wartości stałych izotermy, dlatego można przypuszczać, że jednak bardziej prawidłowy jest model Freundlicha lub inny rodzaj izotermy, który nie był analizowany w toku tych badań.
8
Content available Removal of methylene blue from aqueous solutions with natural olive pomace modified with ultrasounds and acid
Kalipci E.
Environment Protection Engineering
|
2016
|
Vol. 42, nr 3
5--17
EN
Removal of methylene blue (MB) from aqueous solution by raw olive pomace (ROP) which is a waste of industrial olive oil and olive pomace modified with ultrasounds and acid (MOP) has been investigated. It was found that the data for ROP and MOP were well fit to the Freundlich isotherm model (R2 equal to 0.864 and 0.834, respectively). As a result; it was determined that raw olive pomace can be used for the removal of methylene blue dye (KF = 10.08 mg/g(dm3/mg)1/n) and modified olive pomace had high adsorption capacity for MB (KF = 73.08 mg/g(dm3/mg)1/n).
9
Content available Assessment of the sorption properties of materials proposed for the construction of insulation barriers
Sobik-Szołtysek J., Bień J., Grosser A.
Environment Protection Engineering
|
2016
|
Vol. 42, nr 1
169--189
EN
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.
10
Content available Thermodynamics and adsorption studies of dye (rhodamine-b) onto natural diatomite
Koyuncu M., Kul A. R.
Physicochemical Problems of Mineral Processing
|
2014
|
Vol. 50, iss. 2
631--643
EN
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.
11
Content available Adsorption Studies of Nitrate by Geo-Physical Environment (Laterite soil) of the Study Area Bidar Urban & its Industrial Area, Karnataka State, India
Shivasharanappa, Padaki S., Kushtagi S.
International Letters of Chemistry, Physics and Astronomy
|
2013
|
Vol. 6
66-76
EN
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.
12
Content available Utilization of agricultural and industrial wastes for metal removal from aqueous solutions
Biegańska M., Cierpiszewski R.
Polish Journal of Chemical Technology
|
2011
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Vol. 13, nr 1
20-22
EN
In this study a possibility of obtaining sorbents from basketry wastes has been investigated. Therefore, adsorption of cadmium ions on wicker bark of Salix americana has been studied. The obtained experimental results were described by the Freundlich equation and adsorption kinetics by the pseudo-second order equation. The effect of pH on cadmium ions adsorption by S. americana was also investigated. It has been found that for the pH values ranging from 2 to 7 cadmium removal from the solution was held at almost constant level.
13
Określanie stopnia regeneracji zeolitowych sit molekularnych
Gabruś E.
Inżynieria i Aparatura Chemiczna
|
2003
|
Nr 2
13-16
PL
W publikacji przedstawiono metodykę obliczania stopnia regeneracji adsorbentu SR na podstawie badań równowag adsorpcji wody z n—butanolu w układzie ciekłym na zeolitowych sitach molekularnych typu 4A. Do weryfikacji obliczeń symulacyjnych wykorzystano własne dane eksperymentalne dla cyklicznego procesu adsorpcji prowadzonego w kolumnie z nieruchomym złożem.
EN
A method for calculating the adsorbent regeneration ratio, SR, based on batch equilibrium adsorption tests in A4 zeolite molecular sieves and for the water—n—butanol system is presented. The simulation results have been verified employing the experimental data obtained from cyclic adsorption process performed in a fixed bed column.
14
Content available remote Zależność sorpcji pestycydów fenoksyoctowych na węglu AG-5 od ich własności fizyczno-chemicznych
Ignatowicz-Owsieniuk K.
Zeszyty Naukowe Politechniki Białostockiej. Inżynieria Środowiska
|
2001
|
Z. 14
45-54
PL
W opracowaniu przedstawiono wyniki badań dotyczących usuwania herbicydów fenoksyoctowych z wody na węglu AG-5 metodą sorpcji. Doświadczenia miały na celu ustalenie stopnia eliminowania związku w zależności od budowy tego związku i jego własności fizyczno-chemicznych. Wyniki przedstawiono za pomocą izoterm i równań adsorpcji Freundlicha. Stężenie równowagowe pestycydu oznaczano metodami chromatograficznymi - TLC i HPLC.
EN
The purpose of the project was to assess the efficiency of removal of phenoxyacetic pesticides from water by means of activated carbon sorption. The sorbents AG-5 used in this research were domestic products. It was produced by GRYFSKAND, Ltd., Hajnowka. The static research was conducted according to the Chemviron Carbon methodology. Its aim was to determine the Freundlich isotherm and sorption capacity. The residual concentration of the contaminant in the filtrate was determined by the relevant analytical techniques. Also the concentration of phenoxyacetic acid was identified by TLC and HPLC methods.
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