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1

Decolorization of Cationic Dye from Aqueous Solution by Multiwalled Carbon Nanotubes

Ahmed Salwa H., Rasheed Ekehwanh A., Rasheed Luma A., Abdulrahim Firas R.

Journal of Ecological Engineering

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2024

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Vol. 25, nr 2

72--84

EN

Methylene blue is a synthetic and cationic dye that finds utility in different fields including pharmaceutical, paper, textile, printing, carpet, and photography industries. Adsorption is a very effective technique to decolorize contaminated wastewater. This study aimed to determine the efficacy of Multiwalled Carbon Nanotubes (MWCNTs) as an adsorbent for decolorization of MB dye from aqueous solutions. The study examined various characteristics affecting adsorption, including concentration of dye, pH value, dosage of MWCNTs, and contact time. The results that growing the adsorbent dosage from (25 to 120) mg increased the dye efficiency rate from 62% to 98%, respectively, were shown. The study also evaluated pH, which is among the most critical factors influencing removal efficiency. The best pH for the removal efficiency was 6 at an initial concentration of MB dye 20 mgL-1, a contact time 60 min, and an MWCNT dosage 100 mg. Langmuir, Freundlich, and Temkin isotherms were used to describe the adsorption equilibrium. The Langmuir isotherm with an R2 value of 0.9968 and a maximum capacity for adsorption of 19.6 mgg-1 provided a suitable fit for the data of the experiment. In comparison between the suitability of kinetic models pseudo-first-order, pseudo-second order, and Weber–Morris, the kinetics model’s correlation value was shown to be greater than that of the pseudo-second order kinetic model with an R2 value of 0.9982.

2

Simultaneous adsorption of phenol derivatives from water onto spherical activated carbon

Kamiński Władysław, Kuśmierek Krzysztof, Świątkowski Andrzej, Tomczak Elwira

Ecological Chemistry and Engineering. S

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2020

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Vol. 27, nr 3

403--413

EN

The paper examines single- and multicomponent adsorption onto granular activated carbon. The quantities adsorbed in the study were determined using HPLC with UV detection. The experimental data were analysed using the Langmuir, the Freundlich and the Sips adsorption isotherms. With a single component being adsorbed, high coefficients of determination and low mean square errors indicated that the Sips isotherm fitted the adsorption equilibrium well. Further experiments were carried out using aqueous solutions containing two or three adsorbed components in different proportions. For these solutions, the literature methods of predicting multicomponent equilibrium using single-component data did not yield positive results. Assuming that in the investigated range of concentrations no competitive adsorption occurred, the authors propose a method for calculating the equilibrium concentrations in the liquid phase using the equations obtained for individual components. The results achieved correspond very well to the experimental data.

3

Influence of humidity on carbon dioxide adsorptionon zeolite 13X

Zabielska Kamila, Aleksandrzak Tomasz, Gabruś Elżbieta

Chemical and Process Engineering

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2020

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Vol. 41, nr 3

197-–208

EN

Greenhouse gases such as carbon dioxide and water vapour can be captured from gas streams ona zeolite 13X adsorbent. Experimental water vapour adsorption isotherms and kinetic curves weremeasured in the temperature range of 293–393 K and pressure up to 2100 Pa. The equilibrium datawere developed with Toth and Sips multi-temperature isotherm models. The results of the processrate studies were described using pseudo-first and pseudo-second order kinetic models. Findings werecompared with our own results of CO2adsorption studies on the same zeolite

4

Adsorption equilibrium of carbon dioxide on zeolite 1X at high pressures

Zabielska K., Aleksandrzak T., Gabruś E.

Chemical and Process Engineering

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2018

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Vol. 39, nr 3

309–-321

EN

Carbon dioxide (CO2) is a compound responsible for the greenhouse effect. One of the methods of CO2 capture from the gas stream is adsorption process. In this paper, the adsorption equilibrium isotherms of CO2 on zeolite 13X were measured at different temperatures (293.15 K, 303.15 K, 313.15 K, 323.15 K, 333.15 K, 348.15 K, 373.15 K, 393.15 K) and under pressures up to 2 MPa. These data were obtained using an Intelligent Gravimetric Analyzer (IGA-002, Hiden Isochema, UK). Selected multitemperature adsorption isotherm equations, namely Toth, Langmuir–Freundlich, and, Langmuir were correlated with experimental data.

5

Waste Plant Material as a Potential Adsorbent of a Selected Azo Dye

Tomczak E., Tosik P.

Chemical and Process Engineering

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2017

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Vol. 38, nr 2

283--294

EN

This paper discusses the adsorption of Direct Orange 26 azo dye on sunflower husk - an agricultural waste product. During the study, sorption kinetics and equilibrium as well as sorption capacity of the husk were investigated. The adsorption kinetics was analyzed using pseudo-first and pseudo-second order equations, which indicated a chemical sorption mechanism. The sorption equilibrium was approximated with the two-parameter Freundlich and Langmuir equations and the three-parameter Redlich-Peterson equation. The main experiments were carried out in a laboratory adsorption column under different process conditions. Experimental data were interpreted with the Thomas model, based on the volumetric flow rate, initial composition of the feed solution and mass of the adsorbent. The results of modeling the adsorption equilibrium, adsorption kinetics and adsorption dynamics were evaluated statistically.

6

Równowaga adsorpcji izopropanolu na adsorbencie polimerowym Dowex Optipore V503

Ambrożek B., Kruczkowska E., Popiołek P, Ziętarska K

Inżynieria i Aparatura Chemiczna

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2014

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Nr 4

215--216

PL

Przeprowadzono badania równowagi adsorpcji izopropanolu na adsorbencie polimerowym Dowex Optipore V503 stosując metodę dynamiczną. Badania wykonano dla temperatur 293 K, 313 K, 333 K i 353 K oraz ciśnień cząstkowych par izopropanolu zawartych w przedziale 0÷4418 Pa. Do korelacji danych doświadczalnych zastosowano wielotemperaturowe modele Totha i Dubinina-Astachowa. Stosując równanie Clausiusa-Clapeyrona wyznaczono ciepło adsorpcji izopropanolu. Wyniki wykonanych badań wskazują na przydatność adsorbentu polimerowego Dowex Optipore V503 do usuwania izopropanolu z zanieczyszczonych strumieni powietrza.

EN

Adsorption eąuilibrium of isopropanol on Dowex Optipore V503 polymeric adsorbent was studied using a dynamic method. The eąuilibrium experiments were conducted at 293 K, 313 K, 333 K and 353 K, and partial pressures of isopropanol up to 4418 Pa. The experimental data were correlated using multitemperature models of Toth and Dubinin-Astakhov. The isosteric adsorption heat of isopropanol was calculated from the Clausius-Clapeyron equation. The values of isosteric adsorption heat varied with adsorbent-phase loading. It was found that Dowex Optipore V503 polymeric adsorbent is suitable for the isopropanol removal from polluted air streams.

7

Ocena przydatności torfu do usuwania chlorofenoli z roztworów wodnych

Kuśmierek K., Dąbek L., Kamiński W., Świątkowski A.

Ochrona Środowiska

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2013

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Vol. 35, nr 2

51--55

EN

Three chlorophenols of various number of chlorine atoms in the molecule (4-CP, 2,4-DCP and 2,4,6-TCP) were selected for experiments. Removal of these compounds from aqueous solutions has been studied using commercially available Spill-Sorb peat from Parland County (Alberta, Canada). To describe the kinetic data pseudo-first and pseudo-second order models were used. The results showed that the adsorption of chlorophenols on the peat fitted well the pseudo-second order kinetic model. The values of the rate constants k2 decreased with the increase in the initial concentration of chlorophenol and with the increase in the number of chlorine atoms in the molecule. Adsorption was analysed as a function of solution concentration at equilibrium. The experimental data received were found to be well described by the Freundlich isotherm equation. KF and n values increased in the order 4-CP<2,4-DCP<2,4,6-TCP. This suggests that the adsorption efficacy increases with increasing number of chlorine atoms in the chlorophenol molecule.

PL

Do badań wybrano trzy chlorofenole o różnej liczbie atomów chloru w cząsteczce (4-CP, 2,4-DCP i 2,4,6-TCP). Usuwanie tych związków z roztworów wodnych badano używając komercyjnie dostępny torf Spill-Sorb z torfowiska Parland County, Alberta, Kanada. Do opisu danych kinetycznych zastosowano modele pseudo-pierwszego i pseudo-drugiego rzędu. Wyniki pokazały, że adsorpcja chlorofenoli na torfie przebiegała zgodnie z kinetycznym modelem pseudo-drugiego rzędu. Wartości stałych szybkości k2 zmniejszały się wraz ze wzrostem stężenia początkowego chlorofenolu oraz wraz ze wzrostem liczby atomów chloru w cząsteczce. Analizując adsorpcję w funkcji równowagowego stężenia roztworu stwierdzono, że uzyskane dane eksperymentalne dobrze opisywało równanie izotermy Freundlicha. Wartości parametrów KF i n wzrastały w kolejności 4-CP<2,4-DCP<2,4,6-TCP, co sugeruje, że skuteczność adsorpcji wzrastała wraz ze wzrostem liczby atomów chloru w cząsteczce chlorofenolu.

8

Zastosowanie SSN w modelowaniu równowagi sorpcyjnej jonów metali ciężkich na klinoptylolicie

Tomczak E., Kamiński W.

Proceedings of ECOpole

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2012

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Vol. 6, No. 2

664--669

PL

Zainteresowanie sztucznymi sieciami neuronowymi potwierdza wzrost publikacji z dziedziny inżynierii chemicznej, procesowej i ochrony środowiska. Po doborze odpowiedniej architektury sieci i metody uczenia można przystąpić do trenowania sieci na podstawie przeprowadzonych eksperymentów. W takim podejściu nie jest wymagana znajomość matematycznego opis procesu/obiektu. W pracy przedstawiono możliwość przewidywania izoterm sorpcji za pomocą perceptronu wielowarstwowego (MLP) w układach jedno-, dwui wieloskładnikowych. Obliczenia neuronowe oparto na badaniach eksperymentalnych przeprowadzonych dla układu klinoptylolit - mieszanina jonów metali ciężkich: Cu(II), Zn(II), i Ni(II). Jakość obliczeń sprawdzono za pomocą kwadratu współczynnika determinacji i średniego błędu kwadratowego, uzyskując wysoce zadowalające wyniki. Stwierdzono przydatność klinoptylolitu do usuwania jonów metali ciężkich z roztworu. Określono selektywność tego zeolitu zgodnie z szeregiem: Cu(II) > Zn(II) > Ni(II).

EN

The latest achievements in the field of mathematical modelling include the application of artificial neural networks (ANN). A recent dynamic development of ANN provided an efficient and universal tool that is used to solve many tasks, including modelling, approximation and identification of objects. The initial step of applying the network to a given process consists in the determination of weights of the proposed neural network structure. This is performed on the basis of training data. A network that is properly trained allows correct information to be obtained on the basis of other data which have not been used in the network training. In most cases the network training is performed on the basis of a known mathematical model. However, the training of a network can be also performed using experimental data. In the last decade a growing interest is observed in inexpensive and very cheap adsorbents to remove heavy metal ions. Clinoptilolite is the mineral sorbent extracted in Poland used to remove heavy metal ions from diluted solutions. Equilibrium experiments were carried out to estimate sorptivity of a clinoptilolite and its selectivity towards Cu(II), Zn(II) and Ni(II) ions in multicomponent solution. Calculations with the use of MLP enabled description of sorption isotherms for when one, two and three ions were present at the same time in the solution. The network also enabled an analysis of sorption of the selected ion, taking into account the effect of its concentration.

9

Application of ANN to the Sorption Equilibrium Modelling of Heavy Metal Ions on Clinoptilolite

Tomczak E., Kamiński W.

Ecological Chemistry and Engineering. S

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2012

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Vol. 19, nr 2

227-237

EN

The latest achievements in the field of mathematical modelling include the application of artificial neural networks (ANN). A growing interest in the ANN is confirmed by the number of publications devoted to the applicability of ANN in chemical, process and environmental engineering. A recent dynamic development of ANN provided an efficient and universal tool that is used to solve many tasks, including modelling, approximation and identification of objects. The initial step of applying the network to a given process consists in the determination of weights of the proposed neural network structure. This is performed on the basis of training data. A network that is properly trained allows correct information to be obtained on the basis of other data which have not been used in the network training. In most cases the network training is performed on the basis of a known mathematical model. However, the training of a network can be also performed using experimental data. In this paper, the sorption isotherms were predicted by means of a multilayer perceptron (MLP). Calculations were made using a training program written in Matlab, which took advantage of the Lavenberg-Marquardt procedure. In the last decade a growing interest is observed in inexpensive and very cheap adsorbents to remove heavy metal ions. Clinoptilolite is the mineral sorbent extracted in Poland used to remove heavy metal ions from diluted solutions. Equilibrium experiments were carried out to estimate sorptivity of a clinoptilolite and its selectivity towards Cu(II), Zn(II) and Ni(II) ions for multicomponent solution. Calculations with the use of MLP enabled description of sorption isotherms for one, two and three ions which were present at the same time in the solution. The network also enabled an analysis of sorption of the single ion, taking into account the effect of its concentration.

PL

W ostatnich dekadach obserwuje się rosnące zainteresowanie zastosowaniem tanich adsorbentów w celu usuwania zanieczyszczeń z roztworów wodnych. Klinoptylolit jest sorbentem mineralnym wydobywanym w Polsce, stosowanym do usuwania jonów metali ciężkich z rozcieńczonych roztworów. Eksperymenty równowagi przeprowadzono w celu oszacowania efektywności sorpcji klinoptylolitu i jego selektywności wobec Cu(II), Zn(II) i Ni(II) w roztworach wieloskładnikowych. SSN umożliwiają obliczenia izoterm sorpcji dla jednego, dwóch lub trzech jonów jednocześnie obecnych w roztworze. W pracy izotermy sorpcji przewidywano za pomocą wielowarstwowego perceptronu (MLP). Obliczenia prowadzono za pomocą własnych algorytmów zgodnie z procedurą Matlaba z zastosowaniem metody uczenia Lavenberga-Marquardta.

10

Wyznaczanie właściwości separacyjnych adsorbentów do procesów wydzielania ditlenku węgla ze strumieni spalin

Tańczyk M., Jaschik M., Warmuziński K., Janusz-Cygan A., Jaschik J.

Inżynieria i Aparatura Chemiczna

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2010

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Nr 4

82-83

PL

W pracy przedstawiono wyniki badań właściwości separacyjnych adsorbentów do procesu wydzielania CO2 ze strumieni spalin. Stwierdzono, że ZSM 13X są w tym przypadku bardziej odpowiednimi adsorbentami niż węgle aktywne. Najwyższe współczynniki selektywności oraz największe pojemności adsorpcyjne zaobserwowano w przypadku ZSM 13X Grace. Stwierdzono także, że publikowane w literaturze trójparametryczne równania izoterm adsorpcji z podobną, dobrą dokładnością opisują dane doświadczalne.

EN

Results are presented on the separation properties of adsorbents for the removal of CO2 from flue gas streams. It is found that ZMS 13X is, for this particular task, more suitable than activated carbons. The highest selectivity and adsorption capacity were found for ZMS 13X Grace. It is also concluded that the three-parameter isotherms proposed in the relevant literature describe the experimental data with satisfactory and comparable accuracy.

11

Adsorption equilibrium and fixed-bed dynamics for toluene and water vapor mixture on Sorbonorit 4 activated carbon

Nastaj J.F., Ambrożek B., Chybowska M.

Polish Journal of Chemical Technology

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2006

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Vol. 8, nr 1

61-66

EN

A novel method was used to describe adsorption equilibria of nonideal mixtures. The two-dimensional virial equation of state was used for the prediction and correlation of binary adsorption equilibrium of toluene and water vapor on activated carbon at 313.15 K. In this method contributions of single components were separated from those of mixed components. A predictive approach was proposed to calculate cross virial coefficients by using semi-empirical mixing rules. Experimental results were reported from a series of isothermal, fixed bed adsorption dynamics experiments involving mixtures of water and toluene. Breakthrough curves were measured for pure water, toluene, toluene - water mixture and from the mass balance adequate equilibrium points were determined. The experiments were conducted at constant relative humidity (phi(Win} = 0.5). A comparison of the computed results with experimental data for the system toluene - water - activated carbon at 313.15 K was done and fairly good agreement was stated.

12

Wpływ dyspersji wzdłużnej na krzywe przebicia dla układów adsorpcyjnych z nieliniową równowagą

Kupiec K., Zieliński Ł.

Inżynieria Chemiczna i Procesowa

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2001

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T. 22, z. 3C

843--848

PL

W pracy porównano krzywe przebicia wyznaczone na podstawie modelu matematycznego adsorpcji w kolumnie, z krzywymi wyznaczonymi eksperymentalnie. Zgodność krzywych występuje dla Pe = 7. Stosowany model matematyczny uwzględnia opory dyfuzyjne w obu fazach układu oraz nieliniowość równowagi adsorpcyjnej.

EN

This paper presents a comparison between the breakthrough curves obtained by a mathematical model of adsorption in a column and experimental curves. The results are satisfactory for Pe = 7. The considered model takes into account mass transfer resistances in both phases and a non-linear equilibrium.

13

Przewidywanie równowagi adsorpcji mieszaniny rozpuszczalników organicznych na węglu aktywnym

Ambrożek B., Nastaj J.

Inżynieria i Ochrona Środowiska

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2000

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T. 3, nr 3/4

257-286

PL

Przedstawiono wyniki weryfikacji doświadczalnej wybranych modeli równowagi adsorpcji mieszanin gazowych. Badania wykonano dla następujących układów dwuskładnikowych: n-butanol-tetrachlorometan-węgiel aktywny typu N, dichlorometan-benzen-węgiel aktywny typu A32/4 Supersorbon EK, dichlorometan-benzen-węgiel aktywny typu G-BAC Kontisorbon. Do korelacji danych doświadczalnych dla czystych składników badanych mieszanin wykorzystano równania Langmuira, Freundlicha, Freundlicha-Langmuira, Totha oraz Dubinina-Astachowa. Równowagę adsorpcji mieszanin przewidywano, stosując zmodyfikowane modele Langmuira, Freundlicha-Langmuira, Dubinina-Astachowa oraz teorię idealnego roztworu adsorpcyjnego (IAS).

EN

The results of experimental verification of various models of the mixed-gas adsorption equilibrium were presented in this work. Investigations were performed for following two-component adsorption systems: n-butanol-tetrachloromethane-activated carbon type N; di-chloromethane-benzene-A 32/4 Supersorbon EK activated carbon; dichloromethane-benzene-G-BAC Kontisorbon activated carbon. The equations of Langmuir, Freundlich, Freundlich-Langmuir, Toth and Dubinin-Astakhov were used for correlation of the experimental data for pure components. Multicomponent adsorption equilibrium was predicted applying modified Langmuir, Freundlich-Langmuir, Dubinin-Astakhov models and ideal adsorbed solution (IAS) theory.