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1

Analiza wybranych konstrukcji wielozłożowego adsorpcyjnego układu chłodniczego

Neska Mirosław, Opara Tadeusz, Majcher Andrzej

Przemysł Chemiczny

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2024

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T. 103, nr 1

73--78

PL

Omówiono budowę i funkcjonowanie prostego, jednozłożowego adsorpcyjnego układu chłodniczego. Dokonano analizy wybranych konstrukcji układów wielozłożowych. Zweryfikowano opracowany prototyp własnego rozwiązania systemu adsorpcyjnego. Zaprezentowano przykładowe wyniki z weryfikacji układu, dla którego osiągnięto temperaturę w parowniku na poziomie ok. 6°C. Innowacyjnym elementem tego układu był kształt prototypowych adsorberów ze stali nierdzewnej, które są wykonane jako dwa różne rozwiązania konstrukcyjne: walcowo-krzyżowy i walcowo-rurowy. Prezentowane systemy adsorpcyjne, ze względu na swoje parametry pracy, mogą być wykorzystywane do zagospodarowania niskotemperaturowego ciepła odpadowego w przemyśle.

EN

The construction and operation of a simple single-bed adsorption refrigeration system were discussed. Selected designs of multi-bed systems were analyzed. A verified prototype of our own soln. of a threebed adsorption refrigeration system was presented. Examples of results from the verification of the system for which the temp. in the evaporator was reached at the level of approx. 6°C were presented. An innovative element of the system was the shape of the prototype stainless steel adsorbers, which were made in 2 different design solns.: cylindrical-cross and cylindrical-tube. Due to their operational parameters, the presented adsorption systems can be used for the management of low-temp. waste heat in industry.

2

Removal of textile dyes from water using cellulose aerogel

Liugė Monika, Paliulis Dainius, Kumpienė Jūratė, Paulauskienė Tatjana

Ecological Chemistry and Engineering. S

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2024

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Vol. 31, nr 1

49--62

EN

In this study, removal of textile dyes from artificially contaminated water was investigated using sorbent synthesised from cardboard waste. Aerogel - lightweight adsorbent - a material with a low density and large surface area. Aerogels obtained from cellulose, chitosan, lignin or pectin have good adsorption properties for removing organic pollutants from wastewater. The aim of this study was to determine the adsorption efficiency of naphthol green B, congo red, methylene blue and rhodamine B from artificially contaminated water using sorbent synthesised from cardboard waste. The mass of the cellulose aerogel (5 mas. %) adsorbents, that were used in the experiments varied from 1.6 g to 2.74 g. The optimal adsorption conditions were determined as pH = 6.0, concentration of dyes - 10 mg L–1 and 18.0 °C -19.0 °C temperature. Under the optimal conditions, the maximum removal efficiency of naphthol green B using aerogel was 16.45 %; congo red - 98.44 %; methylene blue 79.28 %; and rhodamine B - 52.44 %.

3

Skuteczność syntetycznych zeolitów w usuwaniu metali ciężkich i substancji organicznych z roztworów wodnych

Medykowska Magdalena

Wiadomości Chemiczne

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2023

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[Z] 77, 1-2

97--117

EN

With constantly increasing ecological needs, it is necessary to look for suitable solutions aimed at purifying the water and soil environment. Synthetic zeolites, i.e. porous, ion-exchangeable, acid- and heat-resistant, sodium and calcium aluminosilicates, may be the answer to this demand. This paper presents the adsorption capabilities of two synthetic zeolites (Na-X, Na-P1) obtained via hydrothermal reaction of aqueous sodium hydroxide and high-carbon fly ash. For this purpose, the experiment was conducted with adsorbates from two groups: heavy metals (Pb(II), Zn(II)) and organic substances (polymer - poly(acrylic acid) (PAA), nonsteroidal anti-inflammatory drug – diclofenac (DCF)). Adsorption was carried out in single and mixed adsorbate systems (metal-metal; metal-organic substance; organic substance-organic substance). The adsorption capacity of the studied zeolites was determined relative to Pb(II), Zn(II) and DCF. Desorption processes were also carried out to illustrate the regeneration abilities of the examined porous materials. In addition, the structure of the electrical double layer was characterized using potentiometric titrations and electrophoretic mobility measurements. The highest adsorbed amounts of heavy metals in single systems are observed for Na-X, i.e. 322.1 mg/g Pb(II) and 332.5 mg/g of Zn(II). In the case of Na-P1 zeolite, these amounts were 332.9 mg/g and 103.6 mg/g for Pb(II) and Zn(II), respectively. In mixed adsorbate systems there is a decrease in heavy metal adsorption, after the addition of both another metal or organic substance. In the first case, the decrease is small - the adsorption of Pb(II) on Na-X drops to 309.36 mg/g. In contrast, in mixed systems in the presence of anionic organic substances, the decrease in the amount of adsorbed ions is much greater. In the presence of DCF, Pb(II) adsorption on Na-X decrease to 98.7 mg/g, whereas on Na-P1 to 99.7 mg/g. The main mechanisms of the adsorption process in such systems are: competition for the adsorbent's active sites and the formation of complexes between adsorbates of opposite ionic character. However, the addition of a heavy metal causes increase of the drug adsorption. In the case of Pb(II) ions, the amount of DCF adsorbed on Na-X increases from 6.68 mg/g to 12.86 mg/g, and a slight decrease is observed on Na-P1. On the other hand, in the presence of PAA, DCF adsorption on Na-X decreases to 5.86 mg/g. Moreover, the synthesized adsorbents can be successfully regenerated with hydrochloric acid (in the single and mixed systems containing heavy metals). The addition of Pb(II)/Zn(II) and PAA causes a decrease in the zeta potential of the examined zeolites, whereas the addition of DCF increases this parameter. In turn, the surface charge density decreases in the presence of each adsorbate. It was proved that both synthetic zeolites can be successfully used in soil and water purification processes in continuously improved procedures.

4

Od odpadów rolniczych do wysokowydajnego sorbentu : węgiel aktywny pochodzący z łupin orzechów laskowych do oczyszczania wody i ścieków

Barczak Beata, Klugmann-Radziemska Ewa, Januszewicz Katarzyna

Przemysł Chemiczny

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2023

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T. 102, nr 9

895--899

PL

Łupiny orzechów laskowych, produkt uboczny przemysłu spożywczego, mają znaczny potencjał jako prekursor do produkcji węgla aktywnego ze względu na ich dużą dostępność i dużą zawartość węgla. Przedstawiono badania możliwości przekształcenia łupin orzechów laskowych w węgiel aktywny, wykorzystany do oczyszczania ścieków z zanieczyszczeń organicznych. Porównano procesy aktywacji fizycznej i chemicznej otrzymanego węgla. Otrzymano wysoce porowaty materiał o powierzchni właściwej 1211 m²/g. Ponadto przedstawiono izotermy adsorpcji i oznaczono pojemność adsorpcyjną biowęgla względem rodaminy B.

EN

Hazelnut shells were pyrolyzed at 500°C for 1 h. The obtained biochar was activated phys. with CO₂ at 800°C or chem. with KOH at 850°C. A porous material with a sp. surface area of 1211 m²/g was obtained. The adsorption properties of activated C were tested in relation to the adsorption of rhodamine B. The adsorption capacity was 64.4 mg/g. The Langmuir, Freundlich, Sips and Toth adsorption equil. models were used to describe the rhodamine adsorption isotherm. The best fit to the exptl. data was observed for the Sips isotherm.

5

Effectiveness of polyethylene glycol-coated silica on ions adsorption in industrial wastewater

Maryudi Maryudi, Rahayu Aster, Hakika Dhias Cahya

Polimery

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2023

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Vol. 68, nr 5

259--263

EN

The effect of coating silica with polyethylene glycol on the adsorption of iron and phosphate ions in industrial wastewater was investigated. Variable factors were temperature and time of coating, PEG concentration, and PEG to silica ratio. Infrared spectroscopy and scanning electron microscopy were used to evaluate the chemical structure and morphology of PEG-coated silica. Optimum iron and phosphate ions removal efficiency was obtained using a coating temperature of 50°C, a coating time of 15 min, a PEG concentration of 20%, and a PEG to silica ratio of 1:3.

PL

Zbadano wpływ powlekania krzemionki glikolem polietylenowym na adsorpcję jonów żelaza i fosforanów ze ścieków przemysłowych. Czynnikami zmiennymi były temperatura i czas powlekania, stężenie PEG oraz stosunek PEG do krzemionki. Do oceny budowy chemicznej i struktury krzemionki powlekanej PEG stosowano spektroskopię w podczerwieni i skaningową mikroskopię elektronową. Optymalną skuteczność usuwania jonów żelaza i fosforanów uzyskano stosując temperaturę powlekania 50°C, czas powlekania 15 minut, stężenie PEG 20% oraz stosunek PEG do krzemionki 1:3.

6

The conversıon of ethanol to acetone on a ZnO-CaO catalyst in the presence of water vapor

Baghirova Narqiz N., Mustafayeva Rena E.

Nafta-Gaz

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2023

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R. 79, nr 10

684--689

EN

The main product of the conversion of ethanol to acetone on a ZnO-CaO catalyst is acetone, the yield of which strongly depends on the composition of the reaction environment. When oxygen is present, the yield of products of destructive and complete oxidation increases greatly. In contrast, when water vapor is present, both the selectivity and conversion of ethanol increase. Therefore, the conversion of ethanol is the limiting step in the overall process, which determines the selectivity of the conversion of ethanol to acetone. In this regard, it appeared suitable to investigate the effect of introducing water to the contact zone. As experiments indicated, the addition of water caused a significant effect on the conversion, selectivity, and acetone yield on the ZnO-CaO catalyst. As the partial pressure of water vapor increases, the conversion of ethanol and the acetone yield increase, while the yield of carbon dioxide decreases. The decrease in carbon dioxide is associated not only with the inhibition of the conversion of ethanol to CO2. In this study, the adsorption of water vapor and ammonia on the surface of the ZnO-CaO catalyst was examined by infrared spectroscopy method. It has been shown that water vapor at low temperatures is adsorbed on the catalyst surface in the molecular form, while at higher temperatures it is adsorbed in the dissociative form. Co-transformation reactions of ethanol with acetic acid, acetaldehyde with ethylene, and acetaldehyde with acetic acid have been studied. The obtained results indicated that acetone is formed mainly through the stage of complexation of acetaldehyde with ethylene. The isomerization reaction of 1-butene to 2-butene has been investigated. It was found that the yield of cis-2-butene in the absence of water vapor is higher, likely attributed to the molecular adsorption of water on Lewis centers. Based on these findings, a scheme for the vapor-phase conversion of ethanol into acetone on the studied catalysts was formulated.

PL

Głównym produktem konwersji etanolu do acetonu na katalizatorze ZnO-CaO jest aceton, którego wydajność silnie zależy od składu środowiska reakcji. W obecności tlenu znacznie wzrasta wydajność produktów destrukcyjnego i całkowitego utlenienia. Natomiast w obecności pary wodnej wzrasta selektywność i konwersja etanolu. Dlatego konwersja etanolu jest etapem ograniczającym w całym procesie, który określa selektywność konwersji etanolu do acetonu. W związku z tym celowe wydawało się zbadanie wpływu domieszek wody do strefy kontaktu. Jak wykazały doświadczenia, dodatek wody miał istotny wpływ na konwersję, selektywność i wydajność acetonu na katalizatorze ZnO-CaO. Wraz ze wzrostem ciśnienia cząstkowego pary wodnej wzrasta konwersja etanolu i wydajność acetonu, podczas gdy wydajność dwutlenku węgla maleje. Spadek dwutlenku węgla jest związany nie tylko z hamowaniem konwersji etanolu do CO2. W niniejszej pracy metodą spektroskopii w podczerwieni badano adsorpcję pary wodnej i amoniaku na powierzchni katalizatora ZnO-CaO. Wykazano, że para wodna w niskich temperaturach jest adsorbowana na powierzchni katalizatora w postaci cząsteczkowej, natomiast w wyższych temperaturach jest adsorbowana w postaci dysocjacyjnej. Zbadano reakcje kotransformacji etanolu z kwasem octowym, aldehydu octowego z etylenem i aldehydu octowego z kwasem octowym. Uzyskane wyniki wykazały, że aceton powstaje głównie na etapie kompleksowania aldehydu octowego z etylenem. Zbadano reakcję izomeryzacji 1-butenu do 2-butenu. Stwierdzono, że wydajność cis-2-butenu w nieobecności pary wodnej jest większa, co prawdopodobnie wynika z molekularnej adsorpcji wody na centrach Lewisa. Na podstawie uzyskanych wyników zaproponowano schemat przemiany etanolu do acetonu w fazie gazowej na badanych katalizatorach.

7

Porównanie skuteczności usuwania WWA ze środowiska wodnego z wykorzystaniem biowęgli

Rosińska Agata

Instal

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2023

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nr 10

38--43

PL

Celem badań było porównanie skuteczności usuwania WWA ze środowiska wodnego w wyniku sorpcji na biowęglach otrzymanych z pomiotu kurzego oraz komunalnych osadów ściekowych. Proces sorpcji prowadzono dla dawek biowęgli 50 i 100 mg/l. Dla każdej dawki biowęgla czas kontaktu z WWA wynosił 90 i 120 minut. Najlepsze wyniki uzyskano dla dawki biowęgla 100 mg/l i czasu kontaktu 120 minut. Dla biowęgla z pomiotu kurzego i z osadu ściekowego stężenie benzo(a)pirenu obniżyło się odpowiednio o 87,2 i 78,7% natomiast dla czterech WWA normowanych w wodzie przeznaczonej do spożycia sumaryczne stężenie obniżyło się odpowiednio o 83,5 i 80,2%. Dla pozostałych WWA większą sorpcję zaobserwowano dla dibenzo(a,h)antracenu, stężenie tego związku obniżyło się o 83,2%. Najmniejsze zmiany wykazano dla naftalenu, którego stężenie zmniejszyło się o 68,5%. Nie wykazano istotnych statystycznie różnic pomiędzy sorpcją na biowęglu z pomiotu kurzego i osadu ściekowego.

EN

The aim of the study was to compare the effectiveness of removing PAHs from the aquatic environment as a result of adsorption on biochars obtained from chicken manure and municipal sewage sludge. The sorption process was carried out for doses of biochars of 50 and 100 mg/L. For each dose of biochar, the contact time with PAHs was 90 and 120 minutes. The best results were obtained for a biochar dose of 100 mg/L and a contact time of 120 minutes. For biochar from chicken manure and sewage sludge, the concentration of benzo(a)pyrene decreased by 87.2 and 78.7%, respectively, while for four PAHs standardized in drinking water, the total concentration decreased by 83.5 and 80.2%, respectively. For the remaining PAHs, higher sorption was observed for dibenzo(a,h)anthracene, the concentration of this compound decreased by 83.2%. The smallest changes were shown for naphthalene, the concentration of which decreased by 68.5%. There were no statistically significant differences between sorption on biochar from chicken manure and sewage sludge.

8

Study on the treatment of fluorine-containing wastewater by precipitation-adsorption process

Li Xiaochang, Lyu Xianjun

Environment Protection Engineering

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2023

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Vol. 49, nr 2

55--73

EN

Fluorine-containing wastewater from the Yuncheng Sewage Treatment Plant in Heze City, Shan-dong Province was treated by coagulation and precipitation with poly aluminum sulfate, and CaO chemical precipitation-activated carbon adsorption, with a view to reducing fluoride ions concentration in the wastewater to below the discharge standard. The results showed that the optimum conditions for the coagulation-sedimentation test of poly aluminum sulfate were as follows: the dosage of poly aluminum sulfate 0.3 g/dm3, initial pH value 4.0, the removal rate of fluoride ion in the fluorine-containing wastewater reached 98.46%, and the concentration of fluoride ion was 0.462 mg/ dm3, which reached the discharge standard (1.5 mg/ dm3); The optimum conditions for the CaO chemical precipitation, and lanthanum loaded activated carbon adsorption method were as follows: the amount of CaO 20 g/ dm3, initial pH of the chemical precipitation test 8.0, the dosage of lanthanum loaded activated carbon 10 g/ dm3, and the initial pH of the adsorption test 6.0. At this time, the removal rate of fluoride ions in the fluorine-containing wastewater reached 95.81%, and the concentration of fluoride ions was 1.26 mg/ dm3, which also met the discharge standard.

9

Assessment of the ozonation impact on adsorption efficiency in surface water treatment

Adamski Wojciech, Wisniewski Jacek, Wolska Malgorzata

Environment Protection Engineering

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2023

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Vol. 49, nr 3

95--107

EN

Organic substances in water, both of natural and synthetic origin, especially their share in water treatment by-products can pose a threat to drinkers. That is why adsorption, as a very effective process of dissolved organic compounds removal is commonly used in surface water treatment systems. For process design and optimization, mathematical models both mechanistic and statistics are created. The results of the investigation of granular activated carbon (GAC) bed adsorption in a pilot plant with a capacity of 3 m3/h have been presented. Two systems have been tested – without ozonation and with ozonation before GAC adsorption. The models of the kinetics of GAC adsorption capacity exhaustion, the model of minimal GAC bed depth (adsorption zone) for assumed process efficiency (C/CO), as well as the model of adsorption zone movement velocity to the bottom of GAC bed, have been created. For the state of adsorptive equilibrium, the first model enables the determination of the isotherm parameters of the Freundlich type, the two other models are used for the calculation of GAC bed run time for the certain bed depth and assumed efficiency. It has been shown that in this case (water pollution, GAC type, pretreatment) ozonation plays a minor role.

10

Adsorbent filters for removing polycyclic aromatic hydrocarbons from the atmosphere

Khan Abdul Muqeet, Imran Muhammad, Hashmi Abu Saeed, Shehzad Wasim, Abbas Mateen

Environment Protection Engineering

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2023

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Vol. 49, nr 2

19--27

EN

Indoor activities involving cooking and warming, outdoor sources, smoking, and candle and in-cense burning may introduce a massive portion of polycyclic fragrant hydrocarbons. These are well known for their mutagenicity and carcinogenicity and are omnipresent in urban situations as a result of the combustion of fuel. Due to small particle size, penetration has been suspected to be one major source of indoor polycyclic aromatic hydrocarbons. In the current study, the manufacturing of three types of filters (electrostatic charge-based, pomegranate peel biochar-based, and birds’ feathers-based) was carried out. Their efficiency was tested to remove molecules bounded PAHs and also other geno-toxic compounds associated with these particles. The electrostatic filter was more efficient (27.42%) than pomegranate peel-based and birds’ feathers-based filters (13.86% and 8.32%, respectively). The carcinogenetic effects of PAHs emitted from outdoor and indoor pollutants can be reduced using these kinds of filters.

11

Sustainable production of an iron-eggshell nanocomposite and investigating its catalytic potential for phenol removal

Mohammed Noor A., Saeed Liqaa I., Mhemid Rasha Khalid Sabri

Ecological Chemistry and Engineering. S

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2023

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Vol. 30, nr 3

387--403

EN

The research conducted here will hopefully lead to the creation of a practical, inexpensive method for purging aqueous solutions of contaminating phenolic chemicals. A biosorbent system comprised of eggshells and iron was studied for its potential to effectively detoxify phenol. Both the eggshell and the iron systems were used in the preparation of the adsorbents in order to achieve the desired result of having the properties of both systems. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) were used for characterisation. Batch tests were conducted to evaluate the adsorption capacity of eggshells and iron under the influence of different operating parameters (shaking speed, pH, initial phenol content, and contact time). In the design-expert modelling, the optimisation conditions were found to be a pollutant concentration = 30.0 mg . L–1, pH of 3.00, adsorbent dose = 0.11 mg . L–1, shaking speed = 150 rpm, and time = 120 min for an phenol reduction rate of 94.4 % which it was extremely near to the experimentally value (96.6 %). The CCD modelling that was performed in the RSM verified the findings that were predicted. On the basis of laboratory results, the prediction proved accurate.

12

Adsorption of Rhodamine B from water by activated char obtained from end-of-life tyre pyrolysis

Kuśmierek Krzysztof, Świątkowski Andrzej, Kotkowski Tomasz, Cherbański Robert, Molga Eugeniusz

Chemical and Process Engineering : New Frontiers

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2023

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Vol. 44, nr 1

art. no. e1

EN

Three activated chars obtained from end-of-life tyre pyrolysis differing in activation time (AC110 – 110 min, AC130 – 130 min, and AC150 – 150 min) were successfully used as adsorbents for the removal of model dye – Rhodamine B (RhB) from aqueous solutions. The effects of solution pH, adsorption kinetics, and equilibrium adsorption were investigated. The results showed that the adsorption was strongly pH-dependent; the highest percentage of RhB dye adsorbed was obtained at pH 2.0 and the removal efficiency decreased with an increase in solution pH. Adsorption kinetics was analyzed using pseudo-first-order, pseudo-second-order, Weber-Morris, and Boyd kinetic models. It was found that the pseudo-second-order kinetic equation was the most appropriate for describing the adsorption kinetics and that the RhB adsorption process was controlled by a film diffusion mechanism. Adsorption equilibrium data were fitted to the Langmuir, Freundlich, Temkin, and Elovich isotherm models. The equilibrium data were best represented by the Langmuir model with the monolayer adsorption capacities of 69.96, 94.34, and 133.3 μmol/g for AC110, AC130, and AC150, respectively. It was concluded that the adsorption of RhB was closely correlated with the specific surface area (and activation time) of the activated chars.

13

Study of rational regime and technological parameters of the hydromechanical drilling method

Ihnatov Andrii, Haddad Jamil Sami, Koroviaka Yevhenii, Aziukovskyi Oleksandr, Rastsvietaiev Valerii, Dmytruk Olena

Archives of Mining Sciences

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2023

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Vol. 68, no. 2

285--299

EN

The function of breaking deformations within the rock mass in the bottomhole of a hydromechanical drilling well is dependent on various technological means and methods. A sequential analysis has been conducted to identify the most influential factors in this process. Positive features of hydromechanical drilling have been outlined from the viewpoint of effective intensification of basic technical and economic parameters of the process of well construction with different purposes. Complete operational similarity and technological interconnection of a mechanism of the formation of different parts of a hydromechanical drilling well have been shown in terms of their stipulation by the properties of rock formations and mode support of a well construction process. Top-priority of a hydromechanical drilling type has been proved to generate as many parameters of dynamic effect on rock mass, which results in the increasing scope of bottomhole breaking processes. Attention has been paid to the study of the problem of tool support for drilling operations from the viewpoint of tracing the nature of bottomhole processes running in terms of different technical and technological factors. The possibility and necessity of using surface-active substances (SAS) as the main activators of positive deformation interactions in the “metal pellets – rock” pair have been proved and substantiated; use will be based on the developed methodological approaches of rational selection of a component-concentration composition of a breaking medium. Originality. The efficiency of a hydromechanical drilling type is stipulated by the degree of dynamic effect on the rock bottomhole; depending on its geological-mineralogical and physicomechanical features, it can be intensified by increasing frequency of impacting, interpretation of the effecting mechanism, variation of the cleaning agent type as well as directed activation of the manifestation of surface and interphase interactions. Practical implications. The represented results of analytical and laboratory-experimental studies are the basis for the development of methodological foundations to elaborate the mode parameters of the technology of hydromechanical drilling for the construction of wells. They belong to the basic initial data applied while developing the design and working characteristics of the corresponding modernised operating members.

14

Kinetics models of hydrogen sulphide adsorption from hydrogel biochar derived from empty fruit bunch (EFB)

Alias A.B., Ariffin A.Y., Norain N.M.R., Rashid Z.A.

Archives of Materials Science and Engineering

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2023

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Vol. 120, nr 1

15--21

EN

Purpose: This research aims to investigate the detailed state of adsorption kinetics modelling and research on the application of hydrogen sulfide adsorption by hydrogel derived from empty fruit bunch (EFB), the determination of the kinetics parameters, and the comparison between models in a selection of the best-fit model. Design/methodology/approach: The kinetics modelling used are pseudo-first-order and pseudo-second-order models. The correlation coefficient was used to evaluate the suitability of the equation R2. After obtaining the results, the comparison was made by comparing the R2 of each model. The pseudo-second-order model has a higher value of correlation coefficient, R2, making it the most suitable kinetics model for adsorption systems. Findings: The R2 for pseudo-first-order on the effect of dry bed height was 0.8814, whereas its effect on powder bed height was 0.9537, and that of the wet bed height was 0.9607. Meanwhile, the R2 for pseudo-second-order on the effect of dry bed height was 0.89, on the effect of the powder bed height was 0.99, and on the effect of the bed height of wet was 0.99, the highest among kinetic models. Based on the results, the pseudo-second-order model best describes the adsorption of hydrogen sulfide (H2S) by hydrogel biochar. Research limitations/implications: The kinetics modelling used are pseudo-first-order, and pseudo-second-order models for hydrogen sulfide adsorption by hydrogel originating from empty fruit bunches (EFB). Practical implications: Based on the results, the pseudo-second-order model best describes the adsorption of hydrogen sulfide (H2S) by hydrogel biochar. Kinetic studies are important in understanding the reactions and design of the process. Originality/value: The authenticity results of this article were found to be 17% similar. The novelty of this paper is the kinetics study of the new adsorbent developed based on EFB to adsorb H2S.

15

The influence of chlorine substitution on the adsorption of chlorophenols on HDTMA-modified halloysite in aqueous solutions

Szczepanik Beata, Kołbus Anna, Słomkiewicz Piotr, Czaplicka Marianna

Archives of Environmental Protection

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2023

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Vol. 49, no 2

66--75

EN

This article focuses on discussing the adsorption process of phenol and its chloro-derivatives on the HDTMA-modified halloysite. Optimized chemical structures of phenol, 2-, 3-, 4-chlorophenol, 2,4-dichloro-, and 2,4,6-trichlorophenol were obtained with computational calculation (the Scigress program). Charge distributions and the hypothetical structure of the system HDTMA-modified halloysite are among their key features. The above-mentioned calculations are applied in order to explain adsorption mechanism details of chlorophenols on the HDTMA-modified halloysite in aqueous solutions. The results of electron density distribution and solvent accessible surface area calculations for phenol and chlorophenols molecules illustrate the impact of chlorine substitution position in a phenol molecule, both on the mechanism and the kinetics of their adsorption in aqueous solutions. Experimental adsorption data were sufficiently represented using the Langmuir multi-center adsorption model for all adsorbates. In addition, the relations between adsorption isotherm parameters and the adsorbate properties were discussed. This study also targets at explaining the role of meta position as a chlorine substituent for mono-chloro derivatives. Given the above findings, two possible mechanisms were utilized as regards chlorophenol adsorption on the HDTMA-modified halloysite, i.e., electrostatic and partition interactions when the chlorophenols exist in a molecular form.

16

Sludge-derived biochar : a review on the influence of synthesis conditions on environmental risk reduction and removal mechanism of wastewater pollutants

Lv Ming Yi, Yu Hui Xin, Shang Xiao Yuan

Archives of Environmental Protection

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2023

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Vol. 49, no 2

3--15

EN

In the context of resource utilization, the applications of waste biomass have attracted increasing attention. Previous studies have shown that forming biochar by heat treatment of sludge could replace the traditional sludge disposal methods, and sludge biochar is proved to be efficient in wastewater treatment. In this work, the pyrolysis, hydrothermal carbonization and microwave pyrolysis methods for preparing sludge biochar were reviewed, and the effects of different modification methods on the performance of sludge biochar in the synthesis process were comprehensively analyzed. This review also summarized the risk control of heavy metal leaching in sludge biochar, increasing the pyrolysis temperature and use of the fractional pyrolysis or co-pyrolysis were usually effectively meathods to reduce the leaching risk of heavy metal in the system, which is crucial for the wide application of sludge biochar in sewage treatment. At the same time, the adsorption mechanism of sludge biochar and the catalytic mechanism as the catalytic material in AOPs reaction, the process of radical and non-radical pathway and the possible impacts in the sludge biochar catalytic process were also analyzed in this paper.

17

Removal of Direct Orange 26 azo dye from water using natural carbonaceous materials

Kuśmierek Krzysztof, Dąbek Lidia, Świątkowski Andrzej

Archives of Environmental Protection

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2023

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Vol. 49, no 1

47--56

EN

The aim of the study was to assess the possibility of using natural carbonaceous materials such as peat, lignite, and hard coal as low-cost sorbents for the removal of Direct Orange 26 azo dye from an aqueous solution. The adsorption kinetics and the influence of experimental conditions were investigated. The following materials were used in the research: azo dye Direct Orange 26, Spill-Sorb “Fison” peat (Alberta, Canada), lignite (Bełchatów, Poland), and hard coal (“Zofiówka” mine, Poland). The morphology and porous structure of the absorbents were tested. Dye sorption was carried out under static conditions, with different doses of sorbents, pH of the solution, and ionic strength. It was observed that the adsorption of Direct Orange 26 dye on all three adsorbents was strongly dependent on the pH of the solution, while the ionic strength of the solution did not affect the adsorption efficiency. The adsorption kinetics were consistent with the pseudo-second-order reaction model. The stage which determines the rate of adsorption is the diffusion of the dye in the near-surface layer. The process of equilibrium adsorption of Direct Orange 26 dye on all tested adsorbents is best described by the Langmuir isotherm. The maximum adsorption capacity for peat, brown coal and hard coal was 17.7, 15.1 and 13.8 mg/g, respectively. The results indicate that peat, lignite, and hard coal can be considered as alternative adsorbents for removing azo dyes from aqueous solutions.

PL

Celem pracy była ocena możliwości wykorzystania naturalnych materiałów węglowych takich jak torf, węgiel brunatny i węgiel kamienny jako niskokosztowych sorbentów do w usuwaniu barwnika azowego Direct Orange 26 z roztworu wodnego. Zbadano kinetykę adsorpcji oraz wpływ dawki sorbentu, pH roztworu oraz siły jonowej na skuteczność sorpcji. W badaniach wykorzystano barwnik azowy Direct Orange 26, torf Spill-Sorb „Fison” (Alberta, Kanada), węgiel brunatny (Bełchatów,Polska) oraz węgiel kamienny („Zofiówka”, Polska). Wykonano badania morfologii oraz struktury porowatej absorbentów. Sorpcję barwnika prowadzono w warunkach statycznych, przy różnych dawkach sorbentów, pH roztworu i sile jonowej. Zaobserwowano, że adsorpcja barwnika Direct Orange 26 na wszystkich trzech adsorbentach była silnie zależna od pH roztworu, natomiast siła jonowa roztworu nie wpływała na efektywność adsorpcji. Kinetyka adsorpcji była zgodna z modelem reakcji pseudo-drugiego rzędu. Etapem decydującym o szybkości adsorpcji jest dyfuzja barwnika w warstwie przypowierzchniowej. Proces adsorpcji równowagowej barwnika Direct Orange 26 na wszystkich badanych adsorbentach najlepiej opisuje izoterma Langmuira. Maksymalne zdolności adsorpcyjne dla torfu, węgla brunatnego i węgla kamiennego wynosiły odpowiednio 17,7, 15,1 i 13,8 mg/g. Wyniki wskazują, że torf, węgiel brunatny i węgiel kamienny mogą być rozważane jako alternatywne adsorbenty do usuwania barwników azowych z roztworów wodnych.

18

Układy hybrydowe na bazie krzemionki i haloizytu do zastosowań środowiskowych i biomedycznych

Kurczewska Joanna

Wiadomości Chemiczne

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2022

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[Z] 76, 7-8

529--550

EN

Silica and halloysite are inorganic materials of great importance in various areas of industry. Inorganic-organic hybrid systems obtained on their basis allow for the expansion of potential applications to new directions and improve their properties in the context of possible applications. Silica is characterized by good selectivity and mechanical stability. It consists of siloxane and silanol functional groups that can be functionalized with different organic units. Halloysite is an aluminosilicate clay mineral with silica and alumina sheets. It is often characterized by tubular structure, and its internal and external surfaces can be easily functionalized. Two large areas of application for hybrid materials based on silica and halloysite are environmental protection and medicine. Herein, the exemplary materials dedicated to the adsorption of impurities and drug delivery systems are presented.

19

Polimery funkcjonalne jako unikalne materiały stosowane w selektywnej adsorpcji

Nazim Tomasz, Cegłowski Michał

Wiadomości Chemiczne

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2022

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[Z] 76, 7-8

509--527

EN

Functional polymers are increasingly being used as materials with a range of unique properties. Due to their structure and relatively high flexibility in a synthetic context, they are becoming highly relevant in a variety of applications. One of the numerous examples of the use of functional polymers is water treatment. Using the adsorption phenomenon, it is possible to remove or reduce the amount of harmful organic compounds and heavy metal ions in the water. This review provides information on both the synthesis methods and characterization of functional polymers in terms of their adsorption properties. Among others, this paper presents the results of research on functional polymers carried out by Professor Schroeder's research group. The research was mainly focused on the selective adsorption of dyes and heavy metal ions, which are significant water pollutants. The overall results show that the adsorption of the synthesized polymer materials is high influenced by parameters such as pH, temperature, contact time of the adsorbent with the adsorbate and the initial adsorbate concentration. In the case of the adsorption phenomenon, the Langmuir or Freundlich isotherm turned out to be the most appropriate model for the tested materials, while in the case of kinetic models, the highest R2 coefficient was usually obtained using the pseudo-second-order equation.

20

Grzyby i odpady grzybowe jako nowe prekursory do otrzymywania adsorbentów węglowych

Koźlarek Natalia, Bazan-Woźniak Aleksandra, Pietrzak Robert

Wiadomości Chemiczne

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2022

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[Z] 76, 3-4

221--236

EN

Undesirable changes in the bacteriological, physical and chemical properties of water are a consequence of introduction of excessive amounts of inorganic and organic materials to it. These pollutants limit or prevent the use of water for drinking, food production and household purposes. The greatest amounts of pollutants enter the watersystem with sewage. Also the pesticides,surfactants, organic dyes, artificial fertilizers along with municipal and industrial waste can easily enter water system and threaten the organisms living there. Another, equally important problem is the pollution of atmospheric air. Emission of solid liquid or gas pollutants to the atmosphere has been proved to have significant impact on human health, climate and nature. That is why the search for new and more effective technologies for the environment purification is a continuous challenge. Recently, increasingly often carbon materials are used as effective adsorbents of pollutants from liquid and gas phases.