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Wyszukujesz frazę "Adsorption" wg kryterium: Temat


Tytuł:
Adsorption effectiveness and adsorption efficiency of chosen surfactants
Autorzy:
Rekiel, Edyta Ada
Powiązania:
https://bibliotekanauki.pl/articles/2079921.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet Marii Curie-Skłodowskiej. Wydawnictwo Uniwersytetu Marii Curie-Skłodowskiej
Tematy:
surfactants
biosurfactants
adsorption
adsorption effectiveness
adsorption efficiency
Opis:
Surfactants are various types of chemical compounds that are present in almost every aspect of our life. They are used in many branches of industry, especially in food, cosmetics, pharmaceuticals and even in confectionery. They are considered one of the best solutions for oil residues, soil bioremediation and dealing with PAHs contaminations. Their versatility comes from their amphiphilic build – one part of the compound has hydrophilic properties (head), the other has hydrophobic properties (tail). This fact causes surfactants affinity both to polar and nonpolar compounds. Some of the classical surfactants still can affect fauna and flora by accumulating in ground waters or simply by causing allergies. In that case, many companies decide to limit their surfactant usage and reach for substances present in nature which have very similar, if not better, properties. Biosurfactants are surface active agents produced mainly by microorganisms such as bacteria, fungi and yeasts. There are many papers related to different properties (CMC, aggregation number, surface excess concentration) of various types of surfactants. However, it is difficult to find papers describing the same properties for different surfactants. In this study, adsorption effectiveness and adsorption efficiency at the water-air interface of chosen surfactants: sodium dodecylsulfate (SDDS), cationic: cetyltrimetylammonium bromide (CTAB), nonionic: Triton X-100 (TX-100) and biosurfactants: surfactin (SF) and monorhamnolipid (RL)  has been compared. Both efficiency and effectivenes decide about the practical surfactants application.
Źródło:
Annales Universitatis Mariae Curie-Skłodowska, sectio AA – Chemia; 2019, 74, 2; 25-39
2083-358X
Pojawia się w:
Annales Universitatis Mariae Curie-Skłodowska, sectio AA – Chemia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Adsorption Potential Theory for Description of n-Butane Adsorption on Activated Carbon
Autorzy:
Bałys, Mieczysław
Szczurowski, Jakub
Czepirski, Leszek A.
Kochel, Marek
Powiązania:
https://bibliotekanauki.pl/articles/764132.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Marii Curie-Skłodowskiej. Wydawnictwo Uniwersytetu Marii Curie-Skłodowskiej
Tematy:
adsorption
activated carbon
butane adsorption, adsorption potential therory
heat of adsorption
Opis:
Potential theory of adsorption was used for description of adsorption isotherms of n-butane on microporous active carbon. It was shown that characteristic curve of adsorption can be treated as specific form of thermal equation of adsorption giving the possibility to calculate and predict both equilibrium and thermodynamic characteristics of adsorption in wide range of temperature and relative pressure. The results can be used for the design of adsorption systems and for predicting adsorption equilibrium behavior of binary and/or multicomponent gaseous mixtures on active carbon under wide range of conditions, without time consuming and expensive experimental determination.
Źródło:
Annales Universitatis Mariae Curie-Skłodowska, sectio AA – Chemia; 2016, 71, 2
2083-358X
Pojawia się w:
Annales Universitatis Mariae Curie-Skłodowska, sectio AA – Chemia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental study on the adsorption refrigeration device built on a water-silica gel working pair
Autorzy:
Szelągowski, Adam
Trzcinkowski, Piotr
Powiązania:
https://bibliotekanauki.pl/articles/132051.pdf
Data publikacji:
2019
Wydawca:
Centrum Rzeczoznawstwa Budowlanego Sp. z o.o.
Tematy:
adsorption refrigeration
adsorption
water-silicagel
Opis:
Due to increasing restriction put on compressor based cooling, adsorption cooling has been increasing its popularity. Abovementioned restrictions forces usage of ecological refrigerants, such as water. Additional advantage of adsorption devices is possibility to use low-grade waste heat source or solar energy as the main driving energy instead of electricity. This trend has lead to significant development of adsorption based branch in cooling industry over past 30 years. The paper presents the results of experimental research for an adsorption refrigeration device built of two deposits. Water-silica gel was chosen as the working pair, because this solution allows to work at the lowest drive temperatures. As a result of the experiment, EER coefficients were obtained at the level of 0.57-0.82 and SCP coefficients in the range from 8 to 21 W/kg. The results allow to conclude that adsorption devices can, in many cases compete with compressor solutions.
Źródło:
Modern Engineering; 2019, 1; 42-54
2450-5501
Pojawia się w:
Modern Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Sorption of the acid dyes onto strongly basic anion exchanger: Kinetic and equilibrium studies
Autorzy:
Greluk, M.
Hubicki, Z.
Wołowicz, A.
Powiązania:
https://bibliotekanauki.pl/articles/115757.pdf
Data publikacji:
2011
Wydawca:
Fundacja na Rzecz Młodych Naukowców
Tematy:
adsorption isotherms
adsorption kinetics
acid dyes
resin
Opis:
The strong base acrylic anion exchangers, Amberlite IRA-458, was used as an adsorbent for the investigation of acid dyes (Acid Orange 7, Acid Orange 10 and Acid Red 88) adsorption kinetics and isotherms. The pseudo-fi rst order and pseudo-second order kinetic models were used to analyze the kinetic data and good agreement between the experimental and calculated amounts of dye adsorbed at equilibrium were obtained for the pseudo-second order kinetic models for the entire investigated concentrations domain in the case all three investigated dyes. The adsorption equilibrium data were analyzed by the Langmuir and Freundlich isotherm models with the best fitting being the first one.
Źródło:
Challenges of Modern Technology; 2011, 2, 1; 74-78
2082-2863
2353-4419
Pojawia się w:
Challenges of Modern Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Removal of quinoline from aqueous solutions by lignite, coking coal and anthracite. Adsorption isotherms and thermodynamics
Autorzy:
Xu, H.
Huagn, G.
Li, X.
Gao, L.
Wang, Y.
Powiązania:
https://bibliotekanauki.pl/articles/110016.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
quinoline adsorption
coking coal
adsorption isotherms
thermodynamics
Opis:
Based on the concept of circular economy, a novel method of industrial organic wastewater treatment by using adsorption on coal is introduced. Coal is used to adsorb organic pollutants from coking wastewaters. After adsorption, the coal would be used for its original purpose, its value is not reduced and the pollutant is thus recycled. Through systemic circulation of coking wastewater zero emissions can be achieved. Lignite, coking coal and anthracite were used as adsorbents in batch experiments. The quinoline removal efficiency of coal adsorption was investigated. The coking coal and anthracite exhibited properties well-suited for adsorption onto both adsorbents. The experimental data were fitted to Langmuir and Freundlich isotherms as well as Temkin, Redlich–Peterson (R-P) and Dubinin-Radushkevich (D-R) models. Both Freundlich Isotherm and D-R model provided reasonable models of the adsorption process. The thermodynamic parameters of quinoline adsorption on coking coal were calculated. The thermodynamic parameters indicated that the adsorption process is exothermic and is a physical adsorption. The △S° value indicated that the adsorption entropy decreased because the adsorbate molecule was under restrictions after it adsorption on the coal surface. The coal adsorption method for removing refractory organic pollutants is a great hope for achieving zero emission waste water for a coking plant.
Źródło:
Physicochemical Problems of Mineral Processing; 2016, 52, 1; 214-227
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Removal of quinoline from aqueous solutions by lignite, coking coal and anthracite. Adsorption kinetics
Autorzy:
Xu, H.
Wang, Y.
Huagn, G.
Fan, G.
Gao, L.
Li, X.
Powiązania:
https://bibliotekanauki.pl/articles/110664.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
quinoline adsorption
coking coal
kinetics
adsorption activation energy
coal adsorption
Opis:
Basing on the concept of circular economy, a novel method of industrial organic wastewater treatment by using adsorption on coal is introduced. Coal is used to adsorb organic pollutants from coking wastewaters. After adsorption, the coal would be used in its original purpose, as its value was not reduced and the pollutant was reused. Through the systemic circulation of coking wastewater zero emissions can be achieved. Lignite, coking coal and anthracite were used as adsorbents in batch experiments. The quinoline removal efficiency of coal adsorption was investigated. Both the coking coal and anthracite exhibited properties well-suited for quinoline adsorption removal. The experimental data were fitted to the pseudo-first- order and pseudo-second-order kinetic equations as well as intraparticle diffusion and Bangham models. An attempt was made to find the rate-limiting step involved in the adsorption processes. Both boundary-layer diffusion and intraparticle diffusion are likely involved in the rate-limiting mechanisms. Effect of pH on coal adsorptions by coking coal was investigated. The process of quinoline adsorption on coal was researched. The coal adsorption method for removing refractory organic pollutants is a great hope for achieving wastewater zero emission for coking plants.
Źródło:
Physicochemical Problems of Mineral Processing; 2016, 52, 1; 397-408
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Adsorption behaviors of typical aromatic pollutants in biologically treated coking wastewater on powdered coal
Autorzy:
Sun, H.
Wang, Y.
Bian, Y.
He, X.
Li, G.
Powiązania:
https://bibliotekanauki.pl/articles/110777.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
aromatic pollutants
wastewater treatment
adsorption affinity
competitive adsorption
Opis:
The raw coal was utilized as adsorbent based on its remarkable adsorption ability of coal slime to organic compounds in the flotation process. This paper mainly investigates adsorption behaviors of benzpyrole (BZP), pyrrole (PR) and benzoic acid (BA) on powdered coal (PC). In the monocomponent solution, the removal efficiencies of BZP, PR and BA reached 85.23%, 55.02% and 24.84% at PC dosage of 20 g/dm3. Adsorption behaviors of three pollutants fitted perfectly to the pseudo-second order kinetics model and liquid film diffusion occupied the largest proportion in rate-limiting step according to the diffusion rates. Furthermore, the influences of pH on adsorption behaviors and competitive adsorption mechanism of three pollutants were also reported.
Źródło:
Physicochemical Problems of Mineral Processing; 2018, 54, 2; 496-504
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Kinetics of marine surfactant adsorption at an air-water interface. Baltic Sea studies
Autorzy:
Pogorzelski, S.J.
Kogut, A.D.
Powiązania:
https://bibliotekanauki.pl/articles/48394.pdf
Data publikacji:
2001
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
coastal water
water interface
surface adsorption
marine film
kinetics
Baltic Sea
adsorption barrier
adsorption
Opis:
The paper contains the results of studies of natural surface film adsorption kinetics carried out in inland waters and in shallow offshore regions of the Baltic Sea during 2000–01 under calm sea conditions. The novel approach presented here for the adsorption dynamics is based on the mixed kinetic-diffusion model and analyses of the surface pressure-time plots at short (t → 0) and long (t→∞) adsorption time intervals. Values of the effective relative diffusion coefficient Deff/D (= 0.008 − 0.607) and energy barrier for adsorption Ea/RT (= 0.49 − 7.10) agree well with the data reported for model non-ionic surfactant solutions of pre-cmc concentrations. Wind speed is one of the factors affecting the adsorption barrier via the increased surface pressure of the natural film exposed to wind shear stress (∼ U10 2),a nd enters the relation Ea/RT = 1.70U10 1/3.
Źródło:
Oceanologia; 2001, 43, 4
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Kinetic studies on sorption of ni(ii) and cd(ii) from chloride solutions using selected acidic cation exchangers
Autorzy:
Otrembska, P.
Gega, J.
Powiązania:
https://bibliotekanauki.pl/articles/110403.pdf
Data publikacji:
2013
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
sorption
nickel
cadmium
adsorption kinetics
adsorption isotherm
Opis:
Sorption of nickel(II) and cadmium(II) ions from chloride solutions was tested. Three different strongly acidic cation exchangers, i.e. Lewatit MonoPlus SP 112, Amberlite 200C and Amberlyst 15, were used. Effects of phase contact time, pH and initial concentration of metal ions on equilibrium and kinetics of sorption by batch methods were studied. It was showed that sorption of Ni(II) and Cd(II) could be described by the pseudo-second order equation. Experimental results data were analyzed using the Langmuir and Freundlich isotherms. Sorption of Ni(II) and Cd(II) onto investigated resins followed the Langmuir isotherm.
Źródło:
Physicochemical Problems of Mineral Processing; 2013, 49, 1; 301-312
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Removal of methylene blue from aqueous solution by adsorption onto activated carbon prepared from animal bone and corncob – an agricultural waste
Autorzy:
Ezeugo, J. N. O.
Powiązania:
https://bibliotekanauki.pl/articles/1111953.pdf
Data publikacji:
2018
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Adsorbate
Adsorbent
Adsorption
Synthetic dye
adsorption isotherm
methylene blue
Opis:
Synthetic dyes are widely used in the rubber, textiles, plastics, paper and cosmetics industries to color their products. The effectiveness of adsorption for dye removal from wastewater has made it an ideal alternative to other expensive treatment methods. This study investigates the physicochemical properties of animal-bone- (AB) and corncob- (CC) derived activated carbon on the removal of methylene blue dye. The effects of condition variables such as initial dye concentration, adsorbent dose, pH and contact time were studied. The results show that animal-bone-derived activated carbon has better potential for dye removal than does the corn cob-derived equivalent. AB revealed a higher adsorption capacity of intensity (2.40) and is of higher surface area - 500 m2g–1, while CC has adsorptive capacity of 1.25, intensity of 2.80 and surface area of 420 m2/g–1. What is more, the removal efficiency increases as adsorbent dose increases. This makes it an interesting option for dye removal from aqueous solutions of dye.
Źródło:
World News of Natural Sciences; 2018, 19; 32-44
2543-5426
Pojawia się w:
World News of Natural Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Kinetics and isotherm modelling of Zn(II) ions adsorption onto mine soils
Autorzy:
Jalayeri, H.
Salarirad, M. M.
Ziaii, M.
Powiązania:
https://bibliotekanauki.pl/articles/110575.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
copper mine soil
Zn(II)
adsorption kinetic
adsorption isotherms
Opis:
The soils consist of various components that can play a significant role in control of heavy metals in the environment. Therefore, understanding of adsorption properties of soil is essential in solving pollution problems around mine sites. The goal of this paper is to study Zn(II) ions adsorption onto copper mine soil. Soils were examined via X-ray diffraction and scanning electron microscopy. The influence of various parameters such as effect of pH, adsorbent dose, and initial concentration of Zn(II) ions on adsorption was evaluated by batch method. The adsorption isotherms of Zn(II) ions such as Langmuir, Freundlich, and Temkin were studied. The Langmuir isotherm indicated an excellent fit for the experimental data in comparison with other isotherms that shown monolayer adsorption onto a homogenous surface. A number of kinetic models were tested to fit the kinetic data. The results show that soils can be more effective in decreasing heavy metals contamination specially Zn(II) ions from solution phase.
Źródło:
Physicochemical Problems of Mineral Processing; 2016, 52, 2; 767-779
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of Interactions Between Individual Phenolics of Aronia with Barley Beta-Glucan
Autorzy:
Jakobek, Lidija
Matić, Petra
Ištuk, Jozo
Barron, Andrew R.
Powiązania:
https://bibliotekanauki.pl/articles/1363268.pdf
Data publikacji:
2021-05-11
Wydawca:
Instytut Rozrodu Zwierząt i Badań Żywności Polskiej Akademii Nauk w Olsztynie
Tematy:
adsorption isotherms
adsorption capacity
non-linear models
chokeberry
interactions
Opis:
Beneficial effects of aronia phenolics are determined by their interactions with dietary fibers, such as beta-glucan. The aim of this research was to study interactions between aronia phenolics and beta-glucan by investigating the adsorption process. Phenolic compounds were extracted from aronia, analyzed using high-performance liquid chromatography, and adsorbed onto beta-glucan at pH 1.5. The adsorption data were modeled by using Langmuir, Dubinin-Radushkevich, and Hill isotherms with a novel non-linear regression developed especially for adsorption isotherms. Aronia phenolics adsorbed onto beta-glucan in amounts 31-250 mg/g (individual anthocyanins), 44-123 mg/g (individual flavonols), and 51 mg/g (neochlorogenic acid). The correlation between adsorption capacities and phenolic content was high (r2=0.94), which suggested that the adsorption might be concentration dependent. Modeling with a novel non-linear regression allowed more precise determination of adsorption isotherm parameters. Furthermore, there was a correlation between maximum adsorption capacities predicted by models and measured adsorption capacities (r2 0.76, 0.81, and 0.34 for Langmuir, Dubinin-Radushevich, Hill isotherms, respectively). The suggested bonds involved in interactions are non-covalent bonds (H bonds, Van der Waals forces). Principal component analysis showed that anthocyanins, flavonols, and phenolic acids could differently behave in the adsorption process, which could be due to differences in the chemical structures (ionic nature of anthocyanins, nonionic nature of flavonols and phenolic acids at low pH). In conclusion, aronia phenolics interacted with beta-glucan by adsorbing onto its surface, and the novel modeling developed by our team was helpful in the interpretation of this process. Interactions should be further studied due to their importance for the beneficial effects of aronia.
Źródło:
Polish Journal of Food and Nutrition Sciences; 2021, 71, 2; 187-196
1230-0322
2083-6007
Pojawia się w:
Polish Journal of Food and Nutrition Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Methods of Dyes Removal from Aqueous Environment
Autorzy:
Bożęcka, Agnieszka
Orlof-Naturalna, Monika
Kopeć, Monika
Powiązania:
https://bibliotekanauki.pl/articles/1955552.pdf
Data publikacji:
2021
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
dye
adsorption
wastewater
Opis:
In this paper, selected methods of dyes removal from water environment were discussed, with particular attention to the adsorption method. A literature review of the latest scientific research on colour impurities removal with the use of various types of adsorbents was presented. The efficiency of the methylene blue removal process, with use of selected natural sorbents and activated carbons, was tested. The competitiveness of natural sorbents was shown. It was confirmed that these materials are efficient in removing coloured compounds from aqueous solutions.
Źródło:
Journal of Ecological Engineering; 2021, 22, 9; 111-118
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Atorvastatin adsorption studies on chitosans in an in vitro pharmaceutical model
Autorzy:
Meler, Jan
Grimling, Bożena
Szcześniak, Maria
Karolewicz, Bożena
Biernat, Paweł
Powiązania:
https://bibliotekanauki.pl/articles/1034415.pdf
Data publikacji:
2018
Wydawca:
Sieć Badawcza Łukasiewicz - Polskie Towarzystwo Chitynowe
Tematy:
Atorvastatin
adsorption
chitosan
Opis:
During the pharmacological therapy of specific diseases, drugs are used which, with other preparations or foods, can create connections, in many cases changing or even blocking their action. On the other hand, the use of unsuitable polymers as excipients may result in drug-polymer incompatibilities. Interactions consisting mainly of the occurrence of the adsorption phenomenon and on the formation of complex bonds that reduce the effect of the drugs are of particular importance. The aim of the study was to investigate whether the active substance atorvastatin is incompatible with dietary supplements containing chitosan. The phenomenon of the adsorption of the drug was examined using a static model of a pharmaceutical gastrointestinal tract, in the concentration range generally ingested in a single dose. Measurement results of the amount of bound drug were used to determine the average percentage of adsorbed drug dose. The results of the study prove that the anticholinesterase drug is adsorbed on chitosan in the pH ranges used, and that the binding capacity depends on the chitosan variety, which indirectly affects the reaction of the environment. It was observed that the average size of sorption depending on the chitosan variety ranged from 38% to 86%. The fact that the lowest value of adsorption was at pH 6.4 can be explained by the chemical properties of chitosan, which shows a charge only at pH >6.7. Under such conditions, the phenomenon of electrostatic adsorption may occur in relation to the healing substances of weak acids. At a pH above 7.6, corresponding to the intestinal fluid-filled intestine, the mean sorption for the highest dose of chitosan was from 38–86%. The increase in the adsorbed amount of anticholinesterase drugs on the polymer along with the increase in pH from 7.6 to 8.0 can be explained by the chitosan swelling properties, which increase with an increase in the pH. As a result, the specific surface area of the polymer and its sorption capacity increase. Based on the above considerations, it can be concluded that there is an antagonistic interaction between the drug and the polymer studied, which involves the adsorption of a drug from this group on the polymer (chitosan) and a decrease in its bioavailability
Źródło:
Progress on Chemistry and Application of Chitin and its Derivatives; 2018, 23; 140-148
1896-5644
Pojawia się w:
Progress on Chemistry and Application of Chitin and its Derivatives
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The adsorption of simvastatin on chitosans in an in vitro pharmaceutical model
Autorzy:
Meler, Jan
Grimling, Bożena
Szcześniak, Maria
Pluta, Janusz
Biernat, Paweł
Powiązania:
https://bibliotekanauki.pl/articles/1034541.pdf
Data publikacji:
2017
Wydawca:
Sieć Badawcza Łukasiewicz - Polskie Towarzystwo Chitynowe
Tematy:
adsorption
chitosan
simvastatin
Opis:
In clinical practice for the treatment of obesity, several natural macromolecular compounds are used, whose operation is based on supporting weight loss. During the use of dietary supplements containing chitosan, disease sometimes occurs and treatment for this often comprises different therapeutic agents and antibiotics. The aim of our study was to determine the binding capacity of simvastatin to chitosan, which is found in dietary supplements promoting weight loss, depending on variable physicochemical factors in the gastrointestinal tract model. The phenomenon of adsorption of simvastatin was investigated by a static and dynamic pharmaceutical model (according to the Modified method of Polish Pharmacopoeia IX) simulating the conditions in vitro. The amount of bound drug is used to calculate the average percentage of the adsorbed dose. The obtained results showed that simvastatin is adsorbed by chitosan in the used pH ranges, and the binding capacity is dependent on the environmental pH, viscosity, the concentration of the drug, the type of chitosan and additional substances present in the gastrointestinal tract. The average adsorption of simvastatin in the system of chitosan-nutrients, depending on the pH of the medium, was in the range of 27 to 95%. The highest amount of adsorption was noted above pH 7 (chitosan precipitated polymer forming the emulsion-gel system), when the bioavailability of dietary supplement using chitosan was almost zero.
Źródło:
Progress on Chemistry and Application of Chitin and its Derivatives; 2017, 22; 151-158
1896-5644
Pojawia się w:
Progress on Chemistry and Application of Chitin and its Derivatives
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
In vitro studies of adsorption of erythromycin on chitosans from dietary supplements
Autorzy:
Meler, Jan
Grimling, Bożena
Szcześniak, Maria
Biernat, Paweł
Powiązania:
https://bibliotekanauki.pl/articles/1035189.pdf
Data publikacji:
2014
Wydawca:
Sieć Badawcza Łukasiewicz - Polskie Towarzystwo Chitynowe
Tematy:
Erythromycin
adsorption
chitosan
Opis:
In clinical practice, in the treatment of obesity, a plurality of natural high-molecular compounds are used, the activity of which supports weight loss. During the use of dietary supplements containing chitosan, illness sometimes develops and other therapeutic agents are applied as antibiotics The aim of our study was to determine the binding capacity of the antibiotic erythromycin depending on variable physicochemical factors, in the model of the gastrointestinal tract, by chitosans found in slimming dietary supplements Erythromycin adsorption phenomenon was studied by static and dynamic pharmaceutical model (according to the modified method of the Polish Pharmacopoeia) simulating in vitro conditions. The amount of bound drug was used to calculate the average percentage of the adsorbed dose. The results obtained show that erythromycin is adsorbed by chitosans at various pH ranges, and the binding capacity of the environment depends on the pH, viscosity and concentration of the antibiotic, as well as the chitosan and type and additional substances present in the gastrointestinal tract. The average level of the adsorption of erythromycin in the chitosan-nutrients system depends on the pH of the medium. The highest amount of adsorption was noted above pH 7 (chitosan precipitated polymer forming the emulsion-gel system).
Źródło:
Progress on Chemistry and Application of Chitin and its Derivatives; 2014, 19; 119-123
1896-5644
Pojawia się w:
Progress on Chemistry and Application of Chitin and its Derivatives
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis, Characterization and Cr(VI) Adsorption Properties of Modified Magnetite Nanoparticles
Autorzy:
Çıftçı, H.
Ersoy, B.
Evcın, A.
Powiązania:
https://bibliotekanauki.pl/articles/1031143.pdf
Data publikacji:
2017-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
nanomagnetite
adsorption
Cr(VI)
Langmuir
Freundlich
adsorption kinetics
Opis:
In this study, magnetite (Fe₃O₄) nanoparticles were synthesized by chemical co-precipitation method, coated with silica, and then the surface of silica coated magnetite (Fe₃O₄@SiO₂) nanoparticles was modified with (3-aminopropyl)triethoxysilane (APTES) at first. Secondly, attained nanoparticles were characterized by the Fourier transform infrared, X-ray diffraction, transmission electron microscopy, the Brunauer-Emmett-Teller, vibrating sample magnetometer, and zeta-sizer devices/methods. Finally, detailed adsorption experiments were performed to remove hexavalent chromium (Cr(VI)) from aqueous media by synthesized nanoparticles. Mean size and specific surface area of synthesized nanoparticles were about 15 nm and 89.5 m²/g, respectively. The highest adsorption capacity among used adsorbents (Fe₃O₄, Fe₃O₄@SiO₂, Fe₃O₄@SiO₂@L) was attained by Fe₃O₄ nanoparticles and it was determined that adsorption capacity of the other two adsorbents was too low when compared to the Fe₃O₄ nanoparticles. Optimum conditions for Cr(VI) adsorption by Fe₃O₄ nanoparticles were: pH, 3; temperature, 55°C; contact time, 90 min; adsorbent concentration, 0.5 g/l and initial Cr(VI) concentration 10 mg/l. Under these conditions, adsorption capacity and removal percentage of Cr(VI) were found to be 33.45 mg/g and 88%, respectively.
Źródło:
Acta Physica Polonica A; 2017, 132, 3; 564-569
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analiza uproszczonych równań dynamiki adsorpcji
Analysis of simplified equations of adsorption dynamics
Autorzy:
Piekarski, J.
Dąbrowski, T.
Powiązania:
https://bibliotekanauki.pl/articles/400993.pdf
Data publikacji:
2011
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
adsorpcja
uproszczone równania adsorpcji
adsorption
simplified adsorption equations
Opis:
W zależności od układu, w jakim realizowany jest proces adsorpcji, do jego matematycznego opisu można zastosować równania kinetyki, statyki oraz dynamiki adsorpcji. Najbardziej ogólnym modelem do opisu przebiegu procesu adsorpcji w układzie porcjowym jest model oparty o równanie pola stężeń adsorbatu w wewnętrznej strukturze absorbentu. Dynamika adsorpcji rozpatruje czasowo-przestrzenny rozkład adsorbatu w złożu adsorpcyjnym. W niniejszej publikacji przedstawiono analizę oraz praktyczne wykorzystanie wybranych równań dynamiki procesu adsorpcji do obliczania czasu pracy złoża sorbentu w układzie przepływowym.
Depending on the system, in which the adsorption process is implemented, equations of kinetics, statics and dynamics of adsorption can be applied for its mathematical description. The most general model used for description of adsorption process in the batch system is a model based on field equation of adsorbate concentration in the internal structure of the absorbent. Dynamics of adsorption examines the time-spatial distribution of adsorbate in the adsorbent bed. This publication presents analysis and practical use of selected dynamics equations of adsorption process for calculation of working time of sorbent deposits of in a flow system.
Źródło:
Inżynieria Ekologiczna; 2011, 24; 164-173
2081-139X
2392-0629
Pojawia się w:
Inżynieria Ekologiczna
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Removal of quinoline using various particle sizes anthracite: adsorption kinetics and adsorption isotherms
Autorzy:
Xu, Hongxiang
Sun, Xianfeng
Yu, Yuexian
Liu, Guowei
Ma, Liqiang
Huang, Gen
Powiązania:
https://bibliotekanauki.pl/articles/109567.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
adsorption isotherm
anthracite
particle size
quinoline adsorption kinetics
Opis:
This work provided an adsorption method of the removal of quinoline by using anthracite of various particle sizes. The characteristics of the adsorbents were analyzed by Camsizer XT for particle size analysis, FT-IR for functional groups, X-ray diffusion for mineralogical composition, Brunauer-Emmett-Teller for specific surface area and Barrett-Joyner-Halenda for pore size distribution. The average particle size of AC1-AC4 were 0.0342 mm, 0.1015 mm, 0.2103 mm and 0.3815 mm, respectively. The specific surface of the AC1-AC4 were 3.5 m2·g-1, 1.5 m2·g-1, 0.7 m2·g-1 and 0.1 m2·g-1 respectively. The adsorption capacity present a linear increase with the specific surface area increasing. To reveal the process of the adsorption, the adsorption kinetics and isotherms were performed. The kinetics data were analyzed by pseudo-first-order, pseudo-second-order and intra-particle diffusion equation using linearized correlation coefficient. Pseudo-second-order was found to best represent the kinetics data, which indicated that the adsorption of quinoline onto anthracite belongs to chemisorption. The equilibrium isotherms data were analyzed by Langmuir model and Freundlich model, the results indicated that the Freundlich model fit well for all the adsorption processes, which showed that the adsorption of quinoline onto anthracite belongs to endothermic reaction.
Źródło:
Physicochemical Problems of Mineral Processing; 2019, 55, 1; 196-207
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Adsorption behavior and XPS analysis of nonylphenol ethoxylate on low rank coal
Autorzy:
You, Xiaofang
Ma, Chuandong
Li, Zhihao
Lyu, Xianjun
Li, Lin
Powiązania:
https://bibliotekanauki.pl/articles/109627.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
low rank coal
nonylphenol ethoxylate
adsorption isotherm
adsorption kinetics
XPS
Opis:
In this work, low rank coal was used for the removal of nonylphenol ethoxylate with fifteen ethylene oxide groups (NPEO15) from aqueous solutions at different contact times, temperatures, and initial adsorbent concentrations. The adsorption isotherms showed good fit with the Langmuir equation. Maximum adsorption capacities calculated at 308, 318, and 328 K were 23.64, 29.41, and 35.71 mg g–1, respectively. The changes in the free energy of adsorption (ΔG°), enthalpy (ΔH°), and entropy (ΔS°) were calculated in order to predict the nature of adsorption. The results of the thermodynamic analysis indicated that a spontaneous process took place, driven synergistically by both enthalpy and entropy. The adsorption kinetics of NPEO15 were consistent with a pseudo-second order reaction model. XPS results showed that the oxygen functional groups on the low rank coal surface were significantly covered by NPEO15. Furthermore, while the content of C–C/C–H functional groups increased significantly, that of C–O functional groups decreased after absorption. These results clearly indicate that low rank coal is more hydrophobic and displays better floatability.
Źródło:
Physicochemical Problems of Mineral Processing; 2019, 55, 3; 721-731
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Studies of gentamycin adsorption on chitosan
Autorzy:
Meler, Jan
Grimling, Bożena
Pluta, Janusz
Powiązania:
https://bibliotekanauki.pl/articles/1035211.pdf
Data publikacji:
2013
Wydawca:
Sieć Badawcza Łukasiewicz - Polskie Towarzystwo Chitynowe
Tematy:
Gentamycin
adsorption
chitosan
Opis:
Chitosan as a dietary supplement has been used in the treatment of obesity due to its capability of binding bioactive compounds. A molecule of a cationic polymer, such as chitosan, may bind gentamycin. The aim of the study was to determine the binding capability of Gentamycin by chitosan’s contained in weight-loss supplements. The Gentamycin absorption was investigated by means of a dynamic method in a biopharmaceutical model imitating in vitro conditions including the required level of nutrients. Mean absorption of gentamycin by chitosan ranged from 2,1% to 34,1% depending on the environmental pH. The highest absorption rate was observed at above pH 6,8. Concluding, the studies confirmed that the investigated gentamycin interact with chitosan, what leads to decrease in their amount and affects the bioavailability of the drugs.
Źródło:
Progress on Chemistry and Application of Chitin and its Derivatives; 2013, 18, 18; 175-179
1896-5644
Pojawia się w:
Progress on Chemistry and Application of Chitin and its Derivatives
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Studies on adsorption chloramfenicol on chitosans in pharmaceutical “in vitro” model
Autorzy:
Meler, Jan
Grimling, Bożena
Biernat, Paweł
Pluta, Janusz
Powiązania:
https://bibliotekanauki.pl/articles/1035338.pdf
Data publikacji:
2013
Wydawca:
Sieć Badawcza Łukasiewicz - Polskie Towarzystwo Chitynowe
Tematy:
Chloramphenicol
adsorption
chitosan
Opis:
In clinical practice in the treatment of obesity, uses several natural macromolecular compounds, whose functioning is based on supporting the weight loss. In use of dietary supplements containing chitosan, sometimes reaches the illness and in the treatment, which the other therapeutic agents are chemotherapeutic drugs. The aim of our study was to determine the binding capacity of chloramphenicol chemotherapeutic depending on variable factors physico-chemical properties, present in the intestinal tract model of chitosans present in the drugs. The phenomenon of adsorption of chloramphenicol was examined by a dynamic model simulating the conditions of the pharmaceutical in vitro. the amount of adsorbed chemotherapy. The obtained results show that chloramphenicol is adsorbed by chitosans at pH ranges used, and the binding capacity depends on the pH of the environment and the viscosity and concentration of the chemotherapeutic agent as well as the type of chitosan and the additional substances present in the gastrointestinal tract. The average size of the adsorption system chemotherapeutic chitosan-nutrients depending on the pH of the medium ranged from 22.3 to 100.0%. Maximum number of adsorption points above pH 7 (chitosan precipitated polymer forming the emulsion-gel system).
Źródło:
Progress on Chemistry and Application of Chitin and its Derivatives; 2013, 18, 18; 187-191
1896-5644
Pojawia się w:
Progress on Chemistry and Application of Chitin and its Derivatives
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Studies of norfloxacin adsorption on chitosan
Autorzy:
Meler, Jan
Grimling, Bożena
Pluta, Janusz
Powiązania:
https://bibliotekanauki.pl/articles/1035394.pdf
Data publikacji:
2012
Wydawca:
Sieć Badawcza Łukasiewicz - Polskie Towarzystwo Chitynowe
Tematy:
adsorption
chitosan
norfloxacin
Opis:
In clinical practice a lot of natural macromolecular compounds which operation is based on assisting weight loss are used in the obesity treatment. These measures swell in the digestive tract and form the polymer gel system, which has the ability to adsorb up to 5 times more lipids relative to its own weight. When using dietary supplements containing chitosan, sometimes it comes to illness and in the therapy other agents such as chemotherapeutics are used. The aim of our study was to determine the binding capacity of chemotherapeutic norfloxacin present in the digestive tract model by chitosans found in slimming medicines, depending on variable physico-chemical factors. Phenomenon of norrfloxacin adsorption was studied by a dynamic pharmaceutical model simulating in vitro conditions. The amount of adsorbed chemotherapeutic agent by chitosan was calculated by the difference in concentrations of study drug before and after sorption. The results of measurements of quantities bounded norfloxacin were used to calculate the average percentage of adsorbed dose. The results show that norfloxacin is adsorbed by the chitosans in the applicable pH ranges, and the binding capacity depends on the pH, viscosity and concentration of chemotherapeutics, as well as the type of chitosan and additional substances in the gastrointestinal tract. The average amount of chemotherapeutic adsorption in the system chitosan-nutrients, depending on the pH ranged from 80 to 98%. The highest number of adsorption points above pH 7. In conclusion, the addition of dietary supplement such as chitosan reduces the amount of administered uniformly chemotherapeutic and simultaneously has a large impact on the bioavailability. The observed dependence may require changes in therapeutic process.
Źródło:
Progress on Chemistry and Application of Chitin and its Derivatives; 2012, 17; 103-110
1896-5644
Pojawia się w:
Progress on Chemistry and Application of Chitin and its Derivatives
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fuzzy logic approach in the analysis of heat transfer in a porous sorbent bed of the adsorption chiller
Autorzy:
Grabowska, K.
Krzywański, J.
Sztekler, K.
Kalawa, W.
Nowak, W.
Powiązania:
https://bibliotekanauki.pl/articles/297943.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie
Tematy:
adsorption chiller
porous media
fuzzy logic
thermal conductivity
coated adsorption bed
Opis:
Thermal conductivity in the boundary layer of heat exchange surface is the crucial parameter of adsorption process efficiency which occurs in the adsorption bed. In order to improve heat transfer conditions in the adsorption chiller, novel constructions of adsorption beds are currently investigated. The porous structure of the sorbent layer causes low thermal conductivity in the adsorption bed. One of the methods to improve heat transfer conditions is a modification of porous media bed structure with glue which is characterized with higher thermal conductivity. The optimum parameters of sorbents and glues to build the novel coated construction, in terms of improving the chiller Coefficient of Performance (COP) were defined in (Grabowska et al. 2018a). The paper implements fuzzy logic approach for predicting thermal conductivity of modified porous media layers. The developed model allows determination of the sorbent layer thermal conductivity based on various input parameters: arithmetic average of particle distribution d, density ρ and thermal diffusivity k. The data from empirical research was used to build up the model by fuzzy logic methods.
Źródło:
Technical Sciences / University of Warmia and Mazury in Olsztyn; 2018, 21(4); 281-290
1505-4675
2083-4527
Pojawia się w:
Technical Sciences / University of Warmia and Mazury in Olsztyn
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The influence of alkali concentration and temperature on chemical activation of halloysite
Autorzy:
Maziarz, P.
Powiązania:
https://bibliotekanauki.pl/articles/184280.pdf
Data publikacji:
2016
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
clay mineral
adsorption
structure
Opis:
The influence of alkali activation on clay minerals is not thoroughly investigated, particularly in terms of its impact on adsorption possibilities of clay minerals. One of the studied applications of base treated clay minerals was to control sustained drug release (Wang et al. 2013). Based on the recent studies, the base treatment can cause changes in structure, texture, and morphology of clay minerals. These changes are related to partial dissolution of layered structure and subsequent release of Si and Al to the solution (White et al. 2012, Yuan et al. 2015). This modification can be especially promising in case of halloysite, which is a clay mineral revealing unique nanoscale tubular morphology. Previous studies indicate that selective dissolution of halloysite’s aluminosilicate layers can lead to opening of the tubes interior (lumen) (Wang et al. 2013). This type of structural alteration can influence utilization possibilities of halloysite. Therefore, the aim of this work is to investigate the influence of alkali concentration and reaction temperature on the halloysite structure. The halloysite used in the studies came from Polish deposit located in Dunino, near Legnica (SW Poland) which is constantly exploited. The base activation was carried out using sodium hydroxide (NaOH). Firstly, the effect of NaOH concentration on activation efficiency was investigated. The experiments were carried out for the concentration range from 0.01 to 5.0 mol/L at room temperature. Additionally, for the 1.0 mol/L concentration the experiments were performed at temperatures of 50°C, 60°C, 70°C, 80°C and 90°C. the suspensions consisting of 2 g of halloysite and 50 mL of appropriate solution were mixed for 24 h using magnetic stirrer. Subsequently, the samples were washed with water and dried at 60°C. The prepared materials were characterized using XRD and FTIR methods. The IR results revealed that the concentrations of NaOH below 5 mol/L at room temperature did not cause significant changes in spectra of the tested samples. However, the results of experiments carried out in the temperature range from 60°C to 90°C showed that the temperature of the suspension can significantly affect the alkali activation. Based on the IR spectra the reaction at 50°C did not alter the structure of halloysite, in contrast to 60°C, 70°C, 80°C and 90°C temperatures. The changes of relative intensities of the bands associated with inner surface hydroxyls were observed in the 3700–3600 cm −1 region. These results suggest a gradual removal of inner surface hydroxyls, with the temperature increase. The results also indicated a gradual increase of intensity and broadening of the band with the maximum at 3430 cm −1 and 1647 cm −1 which were attributed to H–O–H stretching and bending vibrations of adsorbed water, respectively. It can be also observed that base treatment at higher temperature also caused structural changes within the aluminosilicate framework of halloysite. The frequency shift and broadening of bands assigned to Si-O-Si stretching (1033 cm −1 , 1008 cm −1 ) and bending (54 0 cm −1 ) vibrations were observed. The perturbations and/or removal of Al-O-H was confirmed by the decrease of bands intensity assigned to bending vibrations at 936 cm −1 and 914 cm −1 The higher temperatures resulted in an appearance of new bands at 1470 cm −1 and 1400 cm −1 associated with carbonates. These bands become more evident with the increase in temperature. The XRD results indicated the formation of additional crystalline phases: sodium aluminum silicate, hydrated sodium carbonates and sodium aluminum carbonate silicate. The presence of carbonates in the samples was confirmed also by FTIR spectra. It was suspected that the presence of carbonate may be related to uptake of atmospheric CO 2 and its reaction with NaOH in accordance with earlier reports by Slaty et al. (2013) and Aldabsheh et al. (2015). The results of this work suggest that different variations of the activation conditions should be examined, to find the optimal temperature for alkaline treatment that leads to an increase in the lumen diameter of halloysite, but does not affect the mineral morphology.
Źródło:
Geology, Geophysics and Environment; 2016, 42, 1; 97-98
2299-8004
2353-0790
Pojawia się w:
Geology, Geophysics and Environment
Dostawca treści:
Biblioteka Nauki
Artykuł

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