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1

Wpływ sposobu aktywacji biowęgla na właściwości węgla aktywnego

Jurkiewicz Martyna, Bilewicz Paweł, Musik Marlena, Kucharska Edyta, Pełech Robert

Przemysł Chemiczny

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2023

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T. 102, nr 3

305--308

PL

Przeprowadzono badania właściwości adsorpcyjnych aktywowanego biowęgla względem adsorpcji błękitu metylenowego (MB) z roztworu wodnego. Przeprowadzono aktywację chemiczną za pomocą chlorku cynku, kwasu fosforowego(V), węglanów wapnia i sodu, wodorowęglanu sodu, wodorotlenków wapnia, sodu i potasu oraz aktywację fizyczną z wykorzystaniem pary wodnej. Uzyskane węgle aktywne charakteryzowały się powierzchnią właściwą w zakresie 180-1300 m²/g. Aktywacja KOH i NaOH umożliwiła uzyskanie węgla aktywnego o największych powierzchniach właściwych. W wyniku aktywacji parowej uzyskano mniejsze rozwinięcie powierzchni, jednak procedura ta znacznie ograniczała ilość powstających ścieków, wykonanych operacji, a także koszt procesu. Do opisu izoterm adsorpcji MB zastosowano model równowagi adsorpcji Langmuira. Obliczona na podstawie tego modelu powierzchnia zajmowana przez cząsteczki MB była zbieżna z wartościami powierzchni właściwej uzyskanymi metodą BET. Wartość stałej równowagi modelu Langmuira skorelowano zależnością wykładniczą z zawartością tlenu w uzyskanych węglach aktywnych.

EN

Biocarbon was chem. activated with ZnCl₂, H₃PO₄ , CaCO₃ , Na₂CO₃ , Ca(OH)₂, NaOH and KOH or phys. activated with steam. The adsorption properties of the activated biocarbon were studied in relation to the adsorption of methylene blue (MB) from aq. soln. The activated carbons had a sp. surface area in the range of 180-1300 m²/g. Activation with KOH and NaOH yielded carbons with the highest sp. surface area, while activation with steam resulted in less surface area development, but significantly reduced the amt. of generated wastewater. The Langmuir adsorption equil. model was used to describe the MB adsorption isotherm. The surface area occupied by MB molecules calculated from the model coincided with the sp. surface area values obtained by the BET method. The value of the equil. constant of the Langmuir model was exponentially correlated with the O content in the obtained activated carbons.

2

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

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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.

3

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

|

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

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

Surface modification of fly ash spheroidal particles and their application in the adsorption of phosphorus and chromium(VI) from single and competitive solute systems

Chen Chen, Cheng Ting, Zhang Xiao, Zhang Minte, Lv Ruiyang

Environment Protection Engineering

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2020

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Vol. 46, nr 3

39--59

EN

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.

6

Adsorption of reactive dyes and their mixtures on activated carbon. Kinetics, equilibrium and thermodynamic evaluation

Kouhail Meriem, Elahmadi Zakia, Benayada Abbes, Dewil Raf

Environment Protection Engineering

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2020

|

Vol. 46, nr 2

5--24

EN

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.

7

Removal of Cr(VI) using a novel adsorbent modification. Ultrasonic method with apricot kernel shells

Kalipci E., Namal O. O.

Environment Protection Engineering

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2018

|

Vol. 44, nr 3

79--93

EN

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.

8

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.

9

Simultaneous removal of NH4+ and PO43- from simulated reclaimed waters by modified natural zeolite. Preparation, characterization and thermodynamics

Alshameri A., He H., Dawood A. S., Zhu J.

Environment Protection Engineering

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2017

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Vol. 43, nr 4

73--92

EN

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.

10

Removal of 2,4,6-trichlorophenol from aqueous solutions using agricultural waste as low-cost adsorbents

Kuśmierek K., Świątkowski A., Dąbek L.

Environment Protection Engineering

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2017

|

Vol. 43, nr 4

149--163

EN

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.

11

Sorption process of Acid Yellow 36 on sludge-based activated carbon

Pieczykolan B., Płonka I.

Proceedings of ECOpole

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2016

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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.

12

Ocena właściwości sorpcyjnych Hottonia palustris L.

Fortalska E., Świsłowski P., Rajfur M.

Proceedings of ECOpole

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2016

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Vol. 10, No. 1

129--136

PL

Zbadano w warunkach laboratoryjnych kinetykę i równowagę procesu sorpcji wybranych metali ciężkich: Cu i Zn w roślinie wodnej - okrężnicy bagiennej (Hottonia palustris L.). Wykazano, że stan równowagi w układzie roztwór soli metalu - okrężnica bagienna zostaje osiągnięty po około 60 minutach. W warunkach prowadzenia eksperymentu około 36% jonów miedzi i około 49% jonów cynku sorbowanych jest z roztworów początkowych w pierwszych 10 minutach. Do opisu równowag wykorzystano model izotermy Langmuira. Stwierdzono, że Hottonia palustris L. sorbuje jony metali ciężkich proporcjonalnie do ich zawartości w roztworze, w którym została zanurzona. Na podstawie przeprowadzonych badań można przypuszczać, że Hottonia palustris L. w przyszłości może być wykorzystywana np. w fitoremediacji wód powierzchniowych oraz jako biomonitor ekosystemów wodnych.

EN

In the laboratory conditions were studied the kinetics and sorption equilibrium of selected heavy metals: Cu and Zn in plant water - colon marsh (Hottonia palustris L.). It has been shown that the equilibrium state in the metal salt solution - marsh colon system is reached after about 60 minutes. Under the conditions of the experiment about 36% copper ions and about 49% zinc ions are sorbed from the initial solutions in the first 10 minutes. To describe the equilibriums was used the Langmuir isotherm model. It was found that Hottonia palustris L. sorbs heavy metal ions in proportion to their content in the solution in which it was submerged. Based on the study it can be assumed that Hottonia palustris L. may be used in the future eg in phytoremediation of surface waters and as biomonitoring of aquatic ecosystems.

13

Removal of reactive blue 29 dye by adsorption on modified chitosan in the presence of hydrogen peroxide

Naghizadeh A., Nabizadeh R.

Environment Protection Engineering

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2016

|

Vol. 42, nr 1

149--168

EN

Industrial effluents that carry dyestuff into natural water systems are serious environmental concern. Complex aromatic structures of dyes make them more stable and more difficult to remove from the effluents discharged into water bodies. In the present study, removal of reactive blue 29 dye with chitosan and modified chitosan with Cu complexes from aqueous solution was investigated in a batch adsorption system with respect to the changes in the contact time, pH of solution and chitosan dosage. Adsorption isotherms of the dye onto chitosan were also studied. The results revealed that the adsorption capacity of chitosan with Cu complexes is lower than that of chitosan without Cu complexes. Also effect of H2O2 on adsorption when we used chitosan without Cu complexes is more considerable. The results also demonstrated that adsorption capacity of reactive blue 29 dye on chitosan was higher at lower pHs. Finally, the Langmuir isotherm showed the best conformity to the equilibrium data.

14

Assessment of the sorption properties of materials proposed for the construction of insulation barriers

Sobik-Szołtysek J., Bień J., Grosser A.

Environment Protection Engineering

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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.

15

Przybliżony model kinetyki adsorpcji mieszaniny węglowodorów na bazie izotermy Langmuira

Pijarowski P. M.

Zeszyty Naukowe. Mechanika / Politechnika Opolska

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2015

|

z. 105

183-186

EN

Process of adsorption kinetics was described in this paper, based on pseudo 1 – row model and other model similar to Langmuir isotherm. To made research of isotherm kinetics adsorption was used inorganic mineral adsorbent applied to remove hazardous substances in chemical and ecological rescue. Heat oil was used as adsorptive.

16

Adsorpcja ołowiu na modyfikowanym węglu aktywnym ROW 08 Supra

Lach J., Okoniewska E., Ociepa-Kubicka A., Szymonik A.

Rocznik Ochrona Środowiska

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2015

|

Tom 17, cz. 1

692--709

EN

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.

17

Sorpcja miedzi w glonach morskich Laminaria ochroleuca Bachelot de la Pylaie

Owczarczak H., Rajfur M.

Proceedings of ECOpole

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2015

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Vol. 9, No. 2

657--665

PL

Zbadano w warunkach laboratoryjnych kinetykę i równowagę procesu sorpcji miedzi w glonach morskich Laminaria ochroleuca Bachelot de la Pylaie. Sorpcję z roztworów siarczanu miedzi prowadzono w warunkach statycznych przy zmniejszającym się stężeniu Cu2+ w roztworze. Zbadano również wpływ sposobu preparowania biomasy glonów na jej właściwości sorpcyjne. Wykazano, że stan równowagi zostaje osiągnięty po około 40 minutach. W warunkach prowadzenia eksperymentu 45-50% jonów miedzi z roztworu początkowego sorbowanych jest w pierwszych 10 min. Do opisu równowag wykorzystano model izotermy Langmuira. Stwierdzono, że glony sorbują jony Cu2+ proporcjonalnie do ich zawartości w roztworze, w którym zostały zanurzone. Można przypuszczać, że 40 min ekspozycja glonów mało zanieczyszczonych metalami ciężkimi, w wodach zanieczyszczonych, spowoduje przyrost stężenia tych analitów proporcjonalnie do ich stężenia w badanych wodach. Uzyskane wyniki porównano z wynikami badań właściwości sorpcyjnych glonów morskich Palmaria palmata oraz glonów słodkowodnych Spirogyra sp. Ze względu na dużą niepewność wyników badań nie podjęto próby wskazania, który z gatunków glonów jest lepszym sorbentem. Na podstawie przeprowadzonych badań można przypuszczać, że glony morskie Laminaria ochroleuca Bachelot de la Pylaie w przyszłości mogą być wykorzystywane np. w fitoremediacji wód powierzchniowych oraz jako bioczujnik w monitoringu ekosystemów wodnych.

EN

The kinetics and equilibrium of sorption process of copper in marine algae Laminaria ochroleuca Bachelot de la Pylaia was examined under laboratory conditions. The sorption from the solution of copper sulfate was performed under static conditions, by decreasing the concentration of Cu2+ in solution. The impact of algal biomass preparation method on its sorption properties was also examined. It has been shown that equilibrium is reached after about 40 minutes. Under the conditions of the experiment 45-50% of copper ions from the initial solution are being sorbed in the first 10 minutes. To describe the equilibriums was used the Langmuir isotherm model. It has been found that algae sorb Cu2+ ions in proportion to their content in the solution in which they are immersed. One can assume that 40 mins exposure of algae contaminated with heavy metals in polluted waters, will increase the concentration of these analytes in proportion to their concentration in the studied waters. The results were compared with the results of the sorption properties of marine algae Palmaria palmata and freshwater algae Spirogyra sp. Due to the high uncertainty of study results no attempt was made to indicate which species of algae is a better sorbent. Based on the study it can be assumed that the seaweed Laminaria ochroleuca Bachelot de la Pylaia may be used in the future eg. in phytoremediation of surface waters and as a biosensor for monitoring of aquatic ecosystems.

18

Biosorption of cationic dyes by beech sawdust. Part I, Kinetics and equilibrium modeling

Witek-Krowiak A., Mitek M., Pokomeda K., Szafran R., Modelski S.

Chemical and Process Engineering

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2010

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Vol. 31, z. 3

409-420

EN

Removal of cationic dyes, rhodamine B and methylene blue, from aqueous solutions by unmodified beech sawdust was investigated. The adsorption kinetics and equilibrium data were fitted by various models. The pseudosecond order kinetics and the Langmuir model described biosorption data reasonably well. The maximum adsorption capacity was 70.40 mg.dm.3 and 52.66 mg.dm.3 for rhodamine B and methylene blue, respectively. The study shows that beech sawdust has the potential off application as an efficient sorbent for removal of cationic dyes.

PL

Sprawdzono skuteczność zastosowania niemodyfikowanych trocin bukowych do usuwania barwników kationowych . rodaminy B i błękitu metylenowego - z roztworów wodnych. Kinetykę i równowagę biosorpcji opisano za pomocą różnych modeli. Najlepszy opis procesu uzyskano, stosując model pseudodrugorzędowy oraz izotermę Langmuira. Pojemność sorpcyjna trocin względem rodaminy i błękitu metylenowego wynosiła odpowiednio 70,40 i 52,66 mg.dm.3. Trociny bukowe okazały się efektywnym sorbentem w usuwaniu barwników kationowych z roztworów wodnych.

19

Wykorzystanie adsorpcji na pylistym węglu aktywnym do usuwania rozpuszczonych substancji organicznych z wody

Szlachta M., Adamski W.

Ochrona Środowiska

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2009

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Vol. 31, nr 2

61-66

PL

Określono skuteczność adsorpcji na pylistym węglu aktywnym (PWA) w usuwaniu rozpuszczonych naturalnych substancji organicznych z wody powierzchniowej. Stwierdzono, że substancje organiczne obecne w badanej wodzie miały duże powinowactwo do adsorbentu, o czym świadczył kształt otrzymanych izoterm adsorpcji. Adsorpcję tych zanieczyszczeń bardzo dobrze opisywał model Langmuira. Badano wydajność adsorpcji w zależności od dawki PWA i czasu kontaktu adsorbentu z wodą naturalną. Sprawność adsorpcji zmieniała się w funkcji czasu kontaktu PWA z wodą, przy czym wykazano, że w pierwszych minutach proces przebiegał bardzo szybko i wówczas sorbowała się większość cząsteczek o mniejszych rozmiarach. Wykazano również, że skuteczność adsorpcji w zmniejszeniu zawartości rozpuszczonego węgla organicznego (RWO) i absorbancji w UV ( =254 nm) rosła z dawką adsorbentu, przy czym większy stopień usunięcia uzyskano w przypadku substancji organicznych o charakterze aromatycznym. Znaczne różnice w skuteczności poszczególnych dawek świadczyły o dobrym wykorzystaniu powierzchni wewnętrznej struktury węgla aktywnego. Ponadto analizowano wpływ jakości wody na skuteczność procesu adsorpcji. W tym celu badano adsorpcję rozpuszczonych związków organicznych z wody surowej bez wstępnego oczyszczania i wody po koagulacji. Odnotowano wzrost adsorpcji substancji organicznych z wody wstępnie oczyszczonej, co mogło być spowodowane usunięciem z wody wielkocząsteczkowych cząstek koloidalnych blokujących dostęp mniejszym frakcjom substancji organicznych do wewnętrznej struktury porowatej węgla aktywnego.

EN

The efficiency of adsorption onto powdered active carbon (PAC) when used for the removal of dissolved organic matter (DOM) from surface water was determined. The DOM that was present in the investigated water showed a high affinity for the adsorbent, as could be inferred from the shape of the adsorption isotherms. The adsorption of these pollutants was well described by the Langmuir model. The efficiency of the adsorption process (which was analyzed in terms of PAC dose and time of contact between the adsorbent and natural water) was found to vary as a function of PAC-water contact time. During the first minutes the process ran at a very fast rate, and at that stage the majority of small-sized particles were subject to sorption. Adsorption efficiency in reducing dissolved organic carbon (DOC) concentration and UV absorbance ( =254 nm) increased with the increase in the adsorbent dose, the extent of removal being higher when the organic substances were of an aromatic nature. The substantial differences in efficiency between particular PAC doses suggested an effective utilization of the internal surface of the carbon's porous structure. Consideration was also given to the influence of water quality on the efficiency of the adsorption process. For this purpose experiments were conducted to determine the extent of DOC adsorption before and after coagulation, and they revealed an increase in the adsorption of DOM from pretreated water. This seems to be attributable to the removal of high-molecular-weight colloids, which may have prevented low-molecular-weight DOM fractions from entering the internal surface of the porous structure of the PAC.

20

Usuwanie zanieczyszczeń organicznych z odcieków składowiskowych metodą adsorpcji na pylistym węglu aktywnym. Część I, Efektywność procesu

Kulikowska D., Sułek P.

Czasopismo Techniczne. Środowisko

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2008

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R. 105, z. 1-Ś

89-98

PL

W niniejszym artykule badano efektywność usuwania zanieczyszczeń organicznych z odcieków składowiskowych metodą adsorpcji na pylistym węglu aktywnym Norit SX2. Odcieki pochodziły z wysypiska ustabilizowanego, o czym świadczą wysoki odczyn (8,34) oraz niska zawartość związków organicznych wyrażonych ChZT (1007 mg/dm[^3]), BZT[5] (108 mg/dm[^3]) i OWO (300 mg/dm[^3]). Indeks zawartości substancji humusowych mierzony na podstawie absorbancji przy długości fali [lambda] = 254 nm i [lambda] = 280 nm wyniósł - odpowiednio - 10,04 i 8,0. Efektywność usuwania zanieczyszczeń organicznych wyrażonych ChZT i RWO zmieniała się w zakresie odpowiednio 30,9-83,3% oraz 29,3-80,5% przy zwiększaniu dawki węgla z 2 g/dm[^3] do 10 g/dm[^3], a w przypadku substancji humusowych mieściła się w przedziale 44.85%. Wyznaczona na podstawie izotermy Langmuira maksymalna pojemność adsorpcyjna węgla Norit SX2 wynosiła 263,2 mg ChZT/g oraz 107,5 mg RWO/g.

EN

In this study the adsorption of organic substances from municipal landfill leachate onto commercial powdered activated carbon Norit SX2 was investigated. The leachate originated from mature landfill, that was confirmed by high pH (8,34) and low concentration of organics expressed as COD (1007 mg/dm[^3]), BOD5 (108 mg/dm[^3]) and DOC (300 mg/dm[^3]). UV[254] and UV[280] as the index of humic substances concentration were 10,04 and 8,0, respectively. The efficiency of organics removal expressed as COD and DOC was in the range of 30,9-83,3% and 29,3-80.5% at the dosage changed from 2 g/dm[^3] to 10 g/dm[^3], respectively. However, in case of humic substances, was in the range from 44 to 85%. The maximum adsorption capacity of Norit SX2 appointed from Langmuir isotherm was 263,2 mg COD/g and 107,5 mg DOC/g.