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Öğe Adsorption capacity of biocarbons from residue of supercritical extraction of raw plants(De Gruyter Open Ltd, 2023) Bazan-Wozniak, Aleksandra; Yılmaz, Selahattin; Nosal-Wiercinska, Agnieszka; Pietrzak, RobertBioadsorbents prepared by chemical activation (H3PO4) of the residue of supercritical extraction of green tea leaves and marigold flowers were characterized by elemental analysis, Boehm titration, adsorption/desorption isotherm and scanning electron microscopy (SEM). The adsorption performance aimed at the removal of malachite green, nitrogen oxide and hydrogen sulfide was investigated. The impacts of various influential parameters of malachite green adsorption such as: contact time (8h), initial dye concentration (20-140mg/L), temperature (25-65°C) and adsorbent mass (0.015-0.025g) were investigated. The adsorption kinetic follows pseudo second-order reaction kinetics (R2 > 0.99). The adsorption process was best described by the Langmuir isotherm and the maximum capacity of the monolayer was from 126.58mg/g to 333.33mg/g for the biocarbons obtained. The negative values of Gibbs free energy indicate the spontaneous character of the process. The presence of steam in the stream of the mixture of gases had a positive effect on adsorption of nitrogen oxide and hydrogen sulfide by the bioadsorbents obtained. The most effective adsorbent of malachite green and toxic gas pollutants proved to be the biocarbon obtained from the residues of supercritical extraction of green tea leaves.Öğe Adsorption of Nitrogen Dioxide on Nitrogen-Enriched Activated Carbons(Mdpi, 2024) Bazan-Wozniak, Aleksandra; Nosal-Wiercinska, Agnieszka; Cielecka-Piontek, Judyta; Yilmaz, Selehattin; Pietrzak, RobertThe aim of this study was to obtain nitrogen-enriched activated carbons from orthocoking coal. The initial material was subjected to a demineralisation process. The demineralised precursor was pyrolysed at 500 degrees C and then activated with sodium hydroxide at 800 degrees C. Activated carbon adsorbents were subjected to the process of ammoxidation using a mixture of ammonia and air at two different temperature variants (300 and 350 degrees C). Nitrogen introduction was carried out on stages of demineralised precursor, pyrolysis product, and oxidising activator. The elemental composition, acid-base properties, and textural parameters of the obtained carbon adsorbents were determined. The activated carbons were investigated for their ability to remove nitrogen dioxide. The results demonstrated that the ammoxidation process incorporates new nitrogen-based functional groups into the activated carbon structure. Simultaneously, the ammoxidation process modified the acid-base characteristics of the surface and negatively affected the textural parameters of the resulting adsorbents. Furthermore, the study showed that all of the obtained carbon adsorbents exhibited a distinct microporous texture. Adsorption tests were carried out against NO2 and showed that the carbon adsorbents obtained were highly effective in removing this gaseous pollutant. The best sorption capacity towards NO2 was 23.5 mg/g under dry conditions and 75.0 mg/g under wet conditions.Öğe Chitin-based porous carbons from Hermetia illucens fly with large surface area for efficient adsorption of methylene blue; adsorption mechanism, kinetics and equilibrium studies(Elsevier B.V., 2024) Bazan-Wozniak, Aleksandra; Nosal-Wiercińska, Agnieszka; Yılmaz, Selehattin; Pietrzak, RobertPrecursor of activated carbon were empty casings of pupas of Hermetia illucens fly. The precursor was subjected either to physical activation (CO2) or chemical activation (H3PO4, K2CO3, Na2CO3). Impregnation with potassium carbonate provided the adsorbent characterized by the best parameters, its surface area was 1167 m2/g, while the maximum sorption capacity towards methylene blue in water solution, according to the Langmuir model was 641.03 mg/g. The best fit to the experimental data was obtained for the pseudo second-order model, which indicated that the process was driven by chemisorption. Moreover, the sorption capacity of the activated carbons increased when pH of the dye solution was higher than pHpzc. The adsorbents obtained by impregnation with K2CO3 may be reused. The study conducted on the thermodynamics of dye adsorption on adsorbents revealed that it was endothermic in nature. The highest efficiency of desorption (80 %) was obtained for 0.5 mol/L of hydrochloric acid.Öğe Kinetics and Mechanism of In(III) Ions Electroreduction on Cyclically Renewable Liquid Silver Amalgam Film Electrode: Significance of the Active Complexes of In(III)-Acetazolamide(MDPI, 2023) Nosal-Wiercinska, Agnieszka; Martyna, Marlena; Pawlak, Alicja; Bazan-Wozniak, Aleksandra; Pietrzak, Robert; Yılmaz, Selehatin; Yağmur Kabaş, SultanThe results of kinetic measurements revealed an accelerating effect of acetazolamide (ACT) on the multistep In(III) ions electroreduction in chlorates(VII) on a novel, cyclically renewable liquid silver amalgam film electrode (R–AgLAFE). The kinetic and thermodynamic parameters were determined by applying the DC polarography, square-wave (SWV) and cyclic voltammetry (CV), as well as electrochemical impedance spectroscopy (EIS). It was shown that ACT catalyzed the electrode reaction (“cap-pair” effect) by adsorbing on the surface of the R–AgLAFE electrode. The catalytic activity of ACT was explained as related to its ability to form active In(III)- acetazolamide complexes on the electrode surface, facilitating the electron transfer process. The active complexes constitute a substrate in the electroreduction process and their different structures and properties are responsible for differences in the catalytic activity. The determined values of the activation energy (Formula presented.) point to the catalytic activity of ACT in the In(III) ions electroreduction process in chlorates(VII). Analysis of the standard entropy values (Formula presented.) confirm changes in the dynamics of the electrode process.Öğe Low-rank coals as precursors of effective carbonaceous adsorbents for the removal of Rhodamine B(Elsevier, 2023) Bazan-Wozniak, Aleksandra; Nosal-Wiercinska, Agnieszka; Yilmaz, Selehattin; Pietrzak, RobertThis article presents the potential of two activated carbons obtained through the chemical activation of low-rank coals from the collieries Labin and Spitsbergen using potassium hydroxide for the adsorption of Rhodamine B dye. The results showed that the obtained adsorbents exhibit a mesoporous texture, and the acidic-basic character of the synthesized adsorbents depends on the starting material. The pseudo-second order kinetic model provided the best fit to the experimental results, indicating that the adsorption process occurred following a chemical process. On the other hand, the Langmuir adsorption isotherm showed the best fit, indicating monolayer adsorption. The Langmuir adsorption isotherm exhibited a high maximum adsorption capacity, which was 175 mg/g and 82 mg/g. Negative values of the Gibbs free energy indicating that the removal of Rhodamine B could be thermodynamically favorable due to the spontaneous nature of the adsorption. The efficiency of Rhodamine B removal by the obtained activated carbons depends on the functional groups present on the surface of the synthesized adsorbents, as well as their porous structure. In turn, desorption studies showed that the most effective eluent was the 0.1 M hydrochloric acid solution.Öğe Microwave-Assisted Fabrication of Fugus-Based Biocarbons for Malachite Green and NO2 Removal(Mdpi, 2023) Bazan-Wozniak, Aleksandra; Yagmur-Kabas, Sultan; Nosal-Wiercinska, Agnieszka; Pietrzak, RobertThe aim of the current study was to produce biocarbons through the activation of carbon dioxide with the extraction residues of the fungus Inonotus obliquus. To achieve this goal, a microwave oven was used to apply three different activation temperatures: 500, 600, and 700 degrees C. Low-temperature nitrogen adsorption/desorption was employed to determine the elemental composition, acid-base properties, and textural parameters of the resulting carbon adsorbents. Subsequently, the produced biocarbons were evaluated for their efficiency in removing malachite green and NO2. The adsorbent obtained by activation of the precursor in 700 degrees C had a specific surface area of 743 m(2)/g. In the aqueous malachite green solution, the highest measured sorption capacity was 176 mg/g. Conversely, under dry conditions, the sorption capacity for NO2 on this biocarbon was 21.4 mg/g, and under wet conditions, it was 40.9 mg/g. According to the experimental findings, surface biocarbons had equal-energy active sites that interacted with the dye molecules. A pseudo-second-order kinetics model yielded the most accurate results, indicating that the adsorption of malachite green was driven by chemisorption. Additionally, the study demonstrates a clear correlation between the adsorption capacity of the biocarbons and the pH level of the solution, as it increases proportionately.
