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1

Wpływ surfaktantów na właściwości adsorpcyjne substancji organicznych i jonów metali ciężkich w układach koloidalnych

Chibowski Stanisław, Wiśniewska Małgorzata

Wiadomości Chemiczne

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2021

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[Z] 75, 9-10

1181--1202

EN

The main purpose of this paper is description of the mechanisms governing the adsorption process of organic substances (such as polymers and dyes soluble in water) and inorganic substances (i.e. heavy metal ions) on the solid surface in the presence of synthetic surfactants of various ionic nature (anionic SDS, cationic CTAB and nonionic Triton X-100). The following polymers were applied: polyacrylamide, poly(ethylene glycol), poly(vinyl alcohol) and poly(acrylic acid). Moreover, the mono-, di- and triazo dyes with acidic, reactive and direct characters were used. Metal oxides – both simple (alumina, zirconia, titania) and mixed (double: silica-alumina, silica-titania and triple: alumina-silica-titania), as well as activated carbons obtained from biomass and peat were applied in the role of adsorbents. The effects of solution pH, ionic character of adsorbate, its molecular weight, elemental composition of the solid, its acid-base properties and textural structure, were determined. The understanding of the phenomena occuring at this type of interface is extremaly important for the effective control of colloidal suspensions stability, which is essential for practical applications. The formation of mixed adsorption layers composed of polymer-surfactant, dye-surfactant or polymer-surfactant-metal ion complexes results in many cases in a significant modification of the surface properties of solids, which is manifested not only by the changes in amount of bound adsorbate, but also by the changes in the structure of electrical double layer. The analysis of the obtained results indicated two main mechanisms of the surfactants influence on the adsorption process of organic and inorganic substances in colloidal systems containing a highly dispersed solid. The first one is the formation of polymer-surfactant, dye-surfactant or polymer-surfactant-metal complexes through both hydrophobic and electrostatic interactions, which show different affinity to the adsorbent surface. In most of the examined systems, these complexes were effectively bound at the solid-liquidinterface, which resulted in the adsorption increase of polymer, dye and heavy metal ions. The second important mechanism is the competition of surfactant molecules and other adsorbates for the active sites of the solid surface (the components of mixed adsorbates had the same ionic character). As a result of these two processes, mixed adsorption layers with a specific structure were formed, which determined the stability of the colloidal suspension.

2

Nowoczesne metody usuwania barwników syntetycznych ze ścieków przemysłowych

Deska Małgorzata, Zawadzki Piotr

Przemysł Chemiczny

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2021

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T. 100, nr 7

664--667

PL

Konieczność spełniania coraz bardziej restrykcyjnych wymogów dotyczących parametrów ścieków przemysłowych odprowadzanych do środowiska sprawia, że badacze na całym świecie skupiają się na poszukiwaniu nowych, ulepszonych metod usuwania barwnych zanieczyszczeń. W pracy uwagę skupiono na zastosowaniu zaawansowanych procesów utleniania (AOPs) oraz wykorzystaniu immobilizowanych enzymów jako obiecujących technologii usuwania zanieczyszczeń barwnych ze ścieków przemysłowych, spełniających zasady „zielonej chemii”.

EN

A review, with 52 refs., of phys.-chem. and biological methods of removing synthetic dyes from wastewater. The advanced oxidn. processes (AOPs) and using of immobilized enzymes in decolorization processes were taken into consideration.

3

Zastosowanie sorbentu haloizytowego do usuwania syntetycznych barwników azowych Acid Red 27 i Reactive Black 5 z roztworów wodnych

Sakiewicz Piotr, Piotrowski Krzysztof, Boryń Dominika, Kruk Milena, Mścichecka Joanna, Korus Irena, Barbusiński Krzysztof

Przemysł Chemiczny

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2020

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T. 99, nr 8

1142--1148

PL

Badano proces adsorpcji syntetycznych barwników azowych Acid Red 27 i Reactive Black 5 z roztworów wodnych z zastosowaniem krajowego haloizytu ze złoża Dunino koło Legnicy, poddanego różnym procesom przygotowania wstępnego. Suszony haloizyt wykazywał lepsze zdolności adsorpcyjne w stosunku do obu barwników niż haloizyt kalcynowany. Możliwości usuwania barwników azowych z roztworu wodnego zależą od wstępnego przygotowania haloizytu (suszenie, kalcynacja, rozdrabnianie), jego klasy ziarnowej, jak również od początkowego stężenia barwnika w oczyszczanym roztworze. Określono wartości parametrów izoterm adsorpcji Langmuira i Freundlicha oraz modeli kinetyki pseudo-pierwszorzędowej i pseudo-drugorzędowej dla badanych układów procesowych.

EN

Two com. azo dyes were removed from aq. solns. by adsorption on a Polish raw halloysite. The dried halloysite samples showed better adsorption efficiency in respect to both dyes than the calcined ones. Sepn. abilities of the azo dyes depended on the preliminary pretreatment of raw halloysite (drying, calcination, milling), size class of the adsorbent fraction used, as well as on the initial concn. of the dye in the soln. The parameters of Langmuir and Freundlich adsorption isotherms, as well as of pseudo-first-order and pseudo-second-order kinetic models for the systems were detd.

4

Chemically modified excessive sludge as an adsorbent of dyes

Pieczykolan Barbara, Płonka Izabela, Zając Robert

Proceedings of ECOpole

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2020

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Vol. 14, No. 1

29--37

EN

In the municipal wastewater treatment technology, the biological method based on the activated sludge process is most commonly used. The activated sludge consists of small flocs, which mainly include bacteria. During the purification process, the growth of microorganisms and their multiplication occurs. Whereby it is necessary to discharge the excess sludge outside the technological system to maintain the concentration of the activated sludge in bioreactor at the appropriate level. Currently, the excess sludge is subjected to the stabilization process (usually biologically) and then it is directed to e.g. agricultural use as fertilizer. In recent years, research is conducted on the use of excessive sludge in the sorption process as a waste sorbent. During the studies, experiments on the use of a chemically modified excess sludge (as an sorbent) to remove two dyes from aqueous solutions (Acid Red 18 and Acid Green 16) were conducted. Excessive activated sludge was thickened, dried at 105 °C and ground to a grain size < 0.49 mm. The sludge was then chemically treated using Fenton's reagent. Next, the adsorption process was carried out. The effect of pH, the effect of reaction time and sorption isotherm was determined. Parameters of three models of isotherms were calculated: Freundlich, Langmuir and Dubinin-Radushkevich.

PL

W technologii oczyszczania ścieków komunalnych najczęściej stosowana jest metoda biologiczna wykorzystująca osad czynny. Osad czynny składa się z małych kłaczków, które głównie zawierają bakterie. Podczas procesu oczyszczania ma miejsce wzrost mikroorganizmów i ich namnażanie. W związku z tym konieczne jest odprowadzenie nadmiaru osadu poza układ technologiczny w celu utrzymania na odpowiednim poziomie stężenia osadu czynnego w bioreaktorze. Obecnie osad nadmierny poddawany jest procesowi stabilizacji (zwykle biologicznej), a następnie kierowany np. do wykorzystania rolniczego jako nawóz. W ostatnich latach prowadzone są badania nad możliwością wykorzystania osadu nadmiernego jako sorbentu odpadowego w procesie sorpcji. Podczas badań przeprowadzono eksperymenty z użyciem chemicznie modyfikowanego osadu nadmiernego (jako sorbentu) do usuwania dwóch barwników z roztworów wodnych (Acid Red 18 oraz Acid Green 16). Nadmierny osad czynny zagęszczono, wysuszono w 105 °C i zmielono do wielkości ziarna < 0,49 mm. Następnie osad poddano obróbce chemicznej z użyciem odczynnika Fentona, po czym przeprowadzono proces adsorpcji. Określono wpływ pH, czas reakcji i wyznaczono izotermę sorpcji. Ponadto obliczono parametry trzech modeli izoterm: Freundlicha, Langmuira i Dubinina-Radushkevicha.

5

Isotherm studies of malachite green removal by yarn processing sludge-based activated carbon

Tang Shu Hui, Zaini Muhammad Abbas Ahmad

Chemistry-Didactics-Ecology-Metrology

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2019

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R. 24, NR 1-2

127--134

EN

Adsorption is an effective wastewater treatment technique which has been widely used in various industrial applications. However, the high operation cost involving commercial activated carbon in industrial processes is the main drawback. Sewage sludge is an auspicious precursor of activated carbon owing to its high carbon content, rich functional groups, low cost, high availability and abundance. This research was aimed to establish the feasibility of converting yarn processing sludge into activated carbon by KI + KOH activation and char at 700 °C for 1 h. The effect of preparation strategies on the properties of sludge-based adsorbents (SBA) was reviewed. The applications of SBAs in the removal of dyes and model pollutants were discussed. The results from this study proved that the preparation of yarn processing sludge-based activated carbon via KI + KOH activation is feasible and effective in the adsorption of dye. This paper provides further insight on the preparation methods of sludge-based adsorbents and dye wastewater treatment using these adsorbents.

6

Application of Spontaneous Oxidation Processes of Zero-valent Iron and Electrocoagulation for Reactive Black 5 Removal

Wysocka I., Filipkowska U., Jóźwiak T.

Fibres & Textiles in Eastern Europe

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2017

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Vol. 25, no. 4 (124)

121--128

EN

Two methods of Reactive Black 5 dye removal were compared in this work, namely electrocoagulation (EC) and one based on spontaneous electrochemical oxidation of zero-valent iron (ZVI). Both methods are based on electrode processes and the sorption process and allow to achieve a similar effectiveness of dye removal. In the case of ZVI, however, a longer contact time or a greater surface area of the electrodes applied is necessary. In turn, the ZVI enables to conduct the processes of dye removal with no requirement for an external source of electric current (lower exploitation inputs). The study demonstrated that the application of both the ZVI method and EC is especially advisable in the case of lower initial concentrations of dye in the solution, i.e. the higher the concentration, the lower the contribution of electrode processes in dye removal from the solution and the greater the contribution of sorption processes.

PL

W ramach niniejszej pracy porównano dwie metody usuwania barwnika Reactive Black 5. Metodę elektrokoagulacji (EC), oraz metodę opartą na samorzutnym elektrochemicznym utlenianiu żelaza na 0 stopniu utlenienia (ZVI). Obie metody wykorzystują procesy elektrodowe oraz procesy sorpcji, umożliwiając uzyskanie podobnej efektywność usuwania barwnika. W przypadku ZVI wymagany jest jednak dłuższy czas kontaktu, lub większa powierzchnia zastosowanych elektrod. ZVI umożliwia jednak przeprowadzenie procesów usuwania barwy, bez konieczności stosowania zewnętrznego źródła prądu (mniejsze nakłady eksploatacyjne). Badania wykazały, że zastosowanie zarówno metody ZVI i EC ma szczególne uzasadnienie w przypadku niższych stężeń początkowych barwnika w roztworze. Im wyższe stężenie, tym udział procesów elektrodowych w usuwaniu barwy roztworu jest mniejszy a przewagę zyskują procesy sorpcji.

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Sorpcja auraminy-0 na powierzchni mezoporowatych węgli utlenionych kwasem azotowym(V)

Marciniak M., Gościańska J., Pietrzak R.

Przemysł Chemiczny

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2016

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T. 95, nr 4

870--873

PL

Uporządkowane mezoporowate węgle otrzymane metodą twardego odwzorowania zostały poddane procesowi utlenienia oraz wykorzystane w procesie adsorpcji auraminy-0. Materiały modyfikowano za pomocą kwasu azotowego(V) w różnych warunkach w celu wygenerowania na ich powierzchni grup funkcyjnych zawierających tlen. Wykazano, że wprowadzenie na powierzchnię węgli tlenowych grup funkcyjnych prowadzi do zmiany właściwości fizykochemicznych materiałów oraz do wzrostu ich efektywności w procesie adsorpcji badanego barwnika. Największą pojemnością sorpcyjną względem auraminy-0 charakteryzuje się materiał utleniony 5 M roztworem HNO₃ w temp. 100°C.

EN

Ordered mesoporous C materials were prepd. by hard template method and treated with HNO₃ at 70 or 100°C under wet oxidn. conditions to study the structure changes and generated surface functionalities. The materials produced were used for removal of auramine-0 dye from aq. Solns. The highest adsorption capacity was obsd. for the material oxidized with 5M HNO₃ at 100°C.

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Removal of methylene blue and methyl blue from wastewater by electrochemical degradation

Samide A., Tutunaru B., Tigae C., Efrem R., Moanta A., Dragoi M.

Environment Protection Engineering

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2014

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Vol. 40, nr 4

93--104

EN

Electrochemical degradation of such dyes as methylene blue (BM-ylene) and methyl blue (BM-yl) was investigated using UV-Vis spectrophotometry, in order to be removed from the solutions, leading to discoloration of wastewater obtained under simulated laboratory conditions. The electrochemical degradation in the presence of SO4(-) ions, as well as in the presence of Cl(-) ions were compared for the synthetic waters containing BM-ylene and BM-yl. The results showed that the fastest degradation and discoloration of the BM-yl solution containing Cl(-) ions was achieved, with a high value for its color removal (CR) of 89.7% obtained after 10 min.

9

Zastosowanie kompostu jako taniego sorbentu do usuwania barwników z roztworów wodnych

Jóźwiak T., Filipkowska U., Rodziewicz J., Mielcarek A., Owczarkowska D.

Rocznik Ochrona Środowiska

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2013

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Tom 15, cz. 3

2398--2411

EN

This study was aimed at determining the feasibility of using compost as an unconventional sorbent for dyes removal from aqueous solutions. Compost applied in the study was a product of sewage sludge composting with plant residues (birch wood chips and rapeseed straw). Experiments were conducted for two anionic reactive dyes: Reactive Yellow 84 [RY84] (1701 g/mol – λmax = 357.5 nm) and Reactive Black 5 [RB5] (991 g/mol – λmax = 600.0 nm), and for two cationic dyes: Basic Green 4 [BG4] (365 g/mol – λmax = 618.0 nm) and Basic Violet 10 [BV10] (479 g/mol – λmax = 547.5 nm). The scope of the study included: determination of the optimal pH value of dyes adsorption onto compost, determination of equilibrium time of dyes sorption onto compost, determination of the maximum sorption capacity of the analyzed dyes on compost. During each experiment, sorbent concentration in the solution was at 5 g d.m./dm3. The concentration of dye remaining in the solution was determined with the spectrophotometric method on a UV-VIS SP 2000 spectrophotometer. Analyses were conducted at a room temperature – T = 22°C. The pH value of solutions was adjusted with aqueous solutions of HCl and NaOH. Sorption of the anionic reactive dyes RY84 and RB5 was the most effective at pH = 3. The optimal pH value of cationic dyes sorption was established at pH = 5. At a high pH value (pH = 9), the sorption of each type of dye was impaired due to partial solubilization of the compost sorbent. The equilibrium time of dyes sorption on compost accounted for 180 min in the case of RY84, RB5 and BG4, and for 240 min in the case of BV10 – 240 min. Analyses of the maximum sorption capacity of the selected dyes on compost were carried out already after establishing the optimal pH value of the sorption process for each dye. Results obtained were described with the use of two sorption models: a heterogenous Langmuir 2 model (double Langmuir equation), and a heterogenousFreundlich model. The Langmuir 2 model showed the best fit to experimental data (R2> 0.99). Due to the presence of functional groups -COOH and -OH, compost is negatively charged in aqueous solutions owing to which it prefers compounds with a positive charge (cationic dyes) during sorption. Electrostatic repulsion significantly impairs the adsorption of anionic dyes. The maximum sorption capacity of compost in the case of RY84 and RB5 reached 2.15 mg/g d.m. and 4.79 mg/g d.m., whereas in the case of BG4 and BV10 – 26.41 mg/g d.m. and 27.20 mg/g d.m., respectively. Results of the maximum sorption capacity of dyes on compost were referred to results obtained with other unconventional and cheap sorbents.

10

Zastosowanie kiszonki z kukurydzy Zea Mays L. do usuwania barwników z roztworów wodnych

Filipkowska U., Jóźwiak T., Rodziewicz J., Kuciejewska J.

Rocznik Ochrona Środowiska

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2013

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Tom 15, cz. 3

2324--2338

EN

The aim of this study was to determine the effectiveness of synthetic dyes removal from aqueous solutions with the use of silage from common maize Zea mays L. as a biosorbent. Two dyes were used as adsorbates: cationic Basic Violet 10 (BV10) and anionic Reactive Black 5 (RB5). The silage from common maize Zea mays L. originated from the Department of Agrotechnology and Plant Production Management, University of Warmia and Mazury in Olsztyn. Before experiments, the silage was dried at a temp. of 60°C for 12 h and then sieved through a sieve with mesh diameter of 0.25 mm. The scope of analyses included determinations of: the effect of biosorbent dose on the course of adsorption process, optimal time of dyes adsorption, and correlation between type of dye and effectiveness of the adsorption process. The effectiveness of RB5 and BV10 adsorption from aqueous solutions onto silage was analyzed based on a correlation between the quantity of adsorbed dye Q (mg/g d.m.), and its equilibrium concentration C (mg/dm3). Results obtained were analyzed with the use of four sorption isotherms: Freundlich, Langmuir, double Langmuir, and Redlich-Peterson. Poorer fit of experimental results to the model was achieved only in the case of Freundlich isotherm. The remaining three models were very well describing the results. Owing to the presence of negative functional groups like e.g. –COOH and –OH in silage, it has a negative charge in aqueous solutions. This has a beneficial impact on the effectiveness of sorption of positively-charged cationic dyes. In turn, electrostatic repulsion of a negatively-charged surface of a biosorbent and anionic dyes exerts a negative effect on sorption effectiveness. The maximum sorption capacity of silage determined for the cationic dye BV10 was ca. 180 mg/g d.m. and was significantly higher than the sorption capacity assayed for the anionic dye RB5 - ca. 80 mg/g d.m. In comparing the achieved results for the sorption of the analyzed dyes RB5 and BV10 onto maize silage with the effectiveness of dyes sorption on other biosorbents, it may be concluded that the waste maize silage displays very good sorption properties and may be successively applied for dye removal.