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Tytuł:
A Change of Traditional Method of Treatment of Partial Thickness Burn with Hydrofibre Dressings
Autorzy:
Mitura, Kryspin
Osłowska, Jolanta
Mitura, Alicja
Powiązania:
https://bibliotekanauki.pl/articles/1395548.pdf
Data publikacji:
2015-02-01
Wydawca:
Index Copernicus International
Tematy:
skin burn wound
partial thickness burn
hydrofiber dressing
silver ions
Opis:
Nearly 1% of population is affected with burn trauma annually. Among patients seeking advanced medical care almost 8% require hospital stay. Most burns are superficial and do not cause full thickness damage to the skin. Standard topical treatment of burn wounds with creams and ointments requires frequent dressings’ changes. The healing process is long and expensive. The technological revolution, as occurred in the last decade in the field of dressing care allows us to introduce the use of advanced material solutions. Modern materials allow to shorten the treatment time, reduce the expenses and diminish the patient discomfort leading to good outcome. The study presented a case of four patients treated due to the partial thickness burn wound. Hydrofiber dressing with silver ions were introduced in the treatment. We observed good short and long term results
Źródło:
Polish Journal of Surgery; 2015, 87, 2; 91-96
0032-373X
2299-2847
Pojawia się w:
Polish Journal of Surgery
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A multi-analytical approach for the analysis of cation distribution in a aluminoceladonite structure
Autorzy:
Kądziołka-Gaweł, Mariola
Dulski, Mateusz
Czaja, Maria
Krzykawski, Tomasz
Szubka, Magdalena
Powiązania:
https://bibliotekanauki.pl/articles/2172615.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
aluminoceladonite
ions position characterization isomorphic substitutions
Fe bearing phyllosilicates
X-ray photoelectron spectroscopy
Mössbauer spectroscopy
Raman spectroscopy
glinokrzemiany
krzemiany warstwowe
rentgenowska spektrometria fotoelektronów
XPS
spektroskopia mössabuerowska
spektroskopia Ramana
Opis:
In this paper cation arrangement in two samples of aluminoceladonite, emerald green and dark-green were studied by Mössbauer, Raman and X-ray photoelectron spectroscopies. The X-ray photoelectron spectroscopy (XPS) spectra obtained in the region of the Si2p, Al2p, Fe2p, K2p, and O1s core levels provided information, for the first time highlighting a route to identify the position of Si, Al, K, and Fe cations in a structure of layered silicates. The XPS analysis showed the presence of Al in tetrahedral and octahedral coordination while the K2p line indicated the possibility of K+ substitution by other cations in interlayer sites. Mössbauer spectroscopy provided information about crystal chemistry with respect to the local electronic and geometric environment around the Fe atom and to distortions of the polyhedra. It turned out that iron was located mostly in the cis-octahedra position wherein about 75% of iron appeared in the form of Fe3+. The most preferred cation combinations around Fe corresponded to 3Fe3+ ions and MgFe2+Fe3+/2MgFe3+. Raman spectroscopy illustrated aluminium substitution in silicon and iron positions wherein the concentration of the aluminium determined the degree of structural distortion within the layered system. These isomorphic substitutions implied a typical band arrangement in the hydroxyl region, which has not been observed in celadonites so far.
Źródło:
Acta Geologica Polonica; 2022, 72, 3; 353--368
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new application of 2–benzoylpyridine – efficient removal of silver ions from acidic aqueous solutions via adsorption process on polymeric material and classic solvent extraction
Autorzy:
Kaczorowska, Małgorzata A.
Bożejewicz, Daria
Witt, Katarzyna
Urbaniak, Włodzimierz
Powiązania:
https://bibliotekanauki.pl/articles/2202879.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
2–benzoylpyridine
adsorptive polymer materials
liquid–liquid extraction
silver(I) and copper(II) ions
mass spectrometry
2-benzoilopirydyna
adsorpcyjne materiały polimerowe
ekstrakcja ciecz-ciecz
jony srebra(I) i miedzi(II).
spekrtometria masy
Opis:
In this article, we present the results of the first application of 2–benzoylpyridine (2–BP) as a carrier in adsorptive polymeric materials dedicated for the removal of Ag(I) and Cu(II) ions from model acidic solutions. In the first stage of the research, the classical solvent extraction, in which 2–BP was used as an extractant, allowed to determine the proper conditions for conducting adsorptive processes. The stability constants of 2–BP complexes with analyzed metal ions were determined using the spectrophotometric method. The electrospray ionization (ESI) high-resolution mass spectrometry (HRMS) method was applied for the confirmation of the ability of 2–BP molecules to form complexes with Cu2 ̧ metal ions in a solution and to determine the elemental composition of generated complexes (to identify the ratio of the number of metal ions to the number of molecules of 2–BP). The obtained results indicate that both the adsorptive processes and solvent extraction strongly depend on the properties of metal ions and that the use of 2–BP as a carrier/extractant allows for efficient removal of silver(I) ions and much less effective removal of copper(II) ions. The utilization of adsorptive polymeric materials is in line with the contemporary research trends that focus on eco-friendly and cost-effective methods.
Źródło:
Chemical and Process Engineering; 2022, 43, 3; 369--382
0208-6425
2300-1925
Pojawia się w:
Chemical and Process Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new cyclotriveratrylene derivative as turn-off fluorescent probe with quinoline appended arm for the selective and sensitive determination of Cu2+ ions
Autorzy:
Fernandes, Patrick F.
Mishra, Divya R.
Powiązania:
https://bibliotekanauki.pl/articles/1030477.pdf
Data publikacji:
2020
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
8-quniolinesulfonyl chloride
Fluorescence studies
Sensors
copper ions
cyclotriveratrylene
Opis:
A novel supramolecular fluorescent molecular probe constructed on cyclotriveratrylene based derivative allied to 8-quinolinesulfonyl chloride (8QSC) was synthesized and used for the detection of copper ions among the various cations. Using 1H-NMR, 13C-NMR, and ESI-MS techniques the compound was successfully characterised. Furthermore the complexation behaviour of 8QSC-CTV with different cations were studied. A shift in the absorption spectra showed the detection of copper ion with the ligand 8QSC-CTV which concludes the strong binding interaction between the ligand and the cation. Furthermore the metal ion showed quenching in the emission spectra. The quantum yield of the metal complex was also studied. The stern volmer analysis concluded that the mechanism of fluorescence quenching is either purely dynamic or purely static.
Źródło:
World Scientific News; 2020, 144; 103-113
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A singular radially symmetric problem in electrolytes theory
Autorzy:
Nadzieja, Tadeusz
Raczyński, Andrzej
Powiązania:
https://bibliotekanauki.pl/articles/1339085.pdf
Data publikacji:
1998
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
radial solutions
electrodiffusion of ions
nonlinear parabolic equation
Opis:
Existence of radially symmetric solutions (both stationary and time dependent) for a parabolic-elliptic system describing the evolution of the spatial density of ions in an electrolyte is studied.
Źródło:
Applicationes Mathematicae; 1998-1999, 25, 1; 101-112
1233-7234
Pojawia się w:
Applicationes Mathematicae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A study of free radical chemistry: their role and pathophysiological significance
Autorzy:
Gutowski, Mariusz
Kowalczyk, Sławomir
Powiązania:
https://bibliotekanauki.pl/articles/1039594.pdf
Data publikacji:
2013
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
ascorbic acid
reactive nitrogen species
catalytic ions
reactive oxygen species
lipid peroxidation
Opis:
Oxygen is one of the most important molecules on Earth mainly because of the biochemical symmetry of oxygenic photosynthesis and aerobic respiration that can maintain homeostasis within our planet's biosphere. Oxygen can also produce toxic molecules, reactive oxygen species (ROS). ROS play a dual role in biological systems, since they can be either harmful or beneficial to living systems. They can be considered a double-edged sword because at moderate concentrations, nitric oxide (NO•), superoxide anion, and related reactive oxygen species play an important role as regulatory mediators in signalling processes. Many of the ROS-mediated responses actually protect the cells against oxidative stress and re-establish "redox homeostasis". On the other hand, overproduction of ROS has the potential to cause damage. In the recent decades, ROS has become a focus of interest in most biomedical disciplines and many types of clinical research. Increasing evidence from research on several diseases shows that oxidative stress is associated with the pathogenesis of diabetes mellitus, obesity, cancer, cardiovascular diseases, inflammation, ischaemia/reperfusion injury, obstructive sleep apnea, neurodegenerative disorders, hypertension and ageing.
Źródło:
Acta Biochimica Polonica; 2013, 60, 1; 1-16
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Superconducting Cyclotron as a primary accelerator for exotic beam facilities
Autorzy:
Maggiore, M.
Rifuggiato, D.
Calabretta, L.
Powiązania:
https://bibliotekanauki.pl/articles/146203.pdf
Data publikacji:
2003
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
cyclotron
ions
medical
superconducting
Opis:
A four sector compact superconducting cyclotron for light ion beams with a maximum energy of 250 MeV/amu has been studied. This cyclotron is mainly designed to accelerate H2 + ions to be extracted by stripping. Ions like C, O or Ne can also be accelerated and extracted by stripping. Extraction by stripping allows to overcome many problems, especially if a certain beam intensity is requested. The preliminary design model of the magnet circuit has been accomplished with the 3D electromagnetic code OPERA [4]. The design of the main coils and of the cryostat has been investigated, too. The features of beam dynamics of this cyclotron, including extraction trajectories, will be presented. Several fields of application have been envisaged for this cyclotron, namely nuclear physics, therapy treatment, interdisciplinary research and radioisotope production using low or medium intensity beams.
Źródło:
Nukleonika; 2003, 48,suppl.2; 165-167
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Acid mine drainage treatment by perlite nanomineral, batch and continuous systems
Oczyszczanie kwaśnych wód kopalnianych przy wykorzystaniu nanominerału perlitu – systemy działania ciągłego i okresowego
Autorzy:
Shabani, K. S.
Ardejani, F. D.
Badii, K.
Olya, M. E.
Powiązania:
https://bibliotekanauki.pl/articles/218773.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
nanocząsteczki perlitu
adsorpcja jonów Cu2+
adsorpcja jonów Fe2+  
adsorpcja jonów Mn2  
kopalnia miedzi i porfirów Sarcheshmeh
systemy działania ciągłego i okresowego
acid mine drainage
perlite nanoparticles
Cu2+, Fe2+ and Mn2+ ions adsorption
Sarcheshmeh porphyry copper mine
batch and continuous systems
Opis:
In this paper the adsorption activity of perlite nanoparticles for removal of Cu2+, Fe2+ and Mn2+ ions at Iran Sarcheshmeh copper acid mine drainage was discussed. Thus, raw perlite that provided from internal resource was modified and prepared via particles size reduction to nano scale and characterized by X-ray diffraction, X-ray fluorescence, scanning electron microscopy, transmission electron microscopy, Fourier transforms infrared and BET specific surface area analysis. The results of acid mine drainage show that pH of acid mine drainage is 5.1 and Cu2+, Fe2+ and Mn2+ ions are 10.5, 4.1 and 8.3 ppm, respectively. Firstly in the batch system the influence of adsorbent dose and temperature parameters were considered and then isothermal and kinetic models were investigated. According to the results the Langmuir isotherm and pseudo-second order kinetic model showed better correlation with the experimental data than other isotherm and kinetic models. Obtained thermodynamic parameters such as ΔG°, ΔH° and ΔS° show that the Cu2+, Fe2+ and Mn2+ ions adsorption from acid mine drainage is spontaneous and endothermic. Finally, perlite nanoparticles adsorbent was packed inside a glass column and used for the removal of heavy metals in 1, 3, 5 ml/min acid mine drainage flow rates, the breakthrough curves show that the column was saturated at 180, 240 and 315 min for different flow rates, respectively. According to the obtained results, this abundant, locally available and cheap silicate mineral showed a great efficiency for the removal of heavy metal pollutants from acid mine drainage and can be utilized for much volume of acid mine drainage or industrial scale.
W pracy omówiono zdolności adsorpcyjne nano-cząsteczek perlitu wykorzystywanych o usuwania jonów Cu2+, Fe2+ i Mn2+ z kwaśnych wód kopalniach w kopalni miedzi w Sarcheshmeh w Iranie. Surowy perlit pozyskiwany ze źródeł własnych został zmodyfikowany i odpowiednio spreparowany poprzez zre-dukowanie cząsteczek do rozmiarów rzędu nano- cząsteczek. Perlit poddany został następnie badaniom z wykorzystaniem dyfrakcji promieniowania rentgenowskiego, rentgenowskiej analizy fluorescencyjnej, skaningowej mikroskopii elektronowej, transmisyjnej mikroskopii elektronowej, spektroskopii w podczerwieni z transformatą Fouriera. Przeprowadzono także badania powierzchni właściwej w oparciu o równanie BET. Wyniki badań kwaśnych wód kopalnianych wykazują ich kwasowość na poziomie 5.1, a zawartość jonów Cu2+, Fe2+ i Mn2 wynosi odpowiednio 10.5, 4.1, 8.3 ppm. W pierwszym etapie analizowano system działania okresowego, zbadano wpływ następujących parametrów: ilości czynnika absorbującego i temperatury. Następnie przebadano modele izotermiczne i kinetyczne. Na podstawie uzyskanych wyników wykazano, że izoterma Langmuira oraz model pseudo-kinetycznego drugiego rzędu wykazują lepszą zgodność z danymi eksperymentalnymi niż pozostałe modele izotermiczne i kinetyczne. Uzyskane parametry termodynamiczne: ΔG°, ΔH° i ΔS° wskazują, że adsorpcja jonów Cu2+, Fe2+ i Mn2 z kwaśnych wód kopalnianych przebiega spontanicznie i jest procesem endotermicznym. W końcowym etapie badania nanocząsteczki perlitu- adsorbentu zostały umieszczone wewnątrz szklanej kolumny i wykorzystane do usuwania jonów metali ciężkich z kwaśnych wód kopalnianych podawanych z prędkością przepływu 1, 3, 5 ml/min. Krzywe przebicia wskazują, że kolumna została nasycona odpowiednio po 180, 240 i 315 dla odpowiednich prędkości przepływu. Uzyskane wyniki wskazują, że ten występujący lokalnie w dużych ilościach, tani i łatwo dostępny minerał krzemianowy wykazuje wysoką skuteczność w usuwaniu z kwaśnych wód kopalniach zanieczyszczeń w postaci metali ciężkich, dlatego też może być z powodzeniem wykorzystany do oczyszczania znacznych ilości wód a także na skalę przemysłową.
Źródło:
Archives of Mining Sciences; 2014, 59, 1; 107-122
0860-7001
Pojawia się w:
Archives of Mining Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Activation mechanism of tantalum niobium flotation by lead ions in a combined collector flotation system
Autorzy:
He, Mingfei
Li, Shuangke
Cao, Miao
Gao, Yude
Bu, Hao
Meng, Qingbo
Powiązania:
https://bibliotekanauki.pl/articles/1448361.pdf
Data publikacji:
2021
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
tantalum niobium ore
Pb2+ ions activation
ammonium dibutyl dithiophosphate
coadsorption
Opis:
The effect of lead ions on the flotation activation of tantalum niobium ore (TNO) was studied by micro-flotation, adsorption capacity experiments, solution chemical composition calculations, and infrared spectral analysis. The experimental demonstrated that the combined collector of salicylhydroxamic acid (SHA) and ammonium dibutyl dithiophosphate (ADDP) resulted in a strong collection capacity for TNO in the presence of lead ions. The solution chemistry calculations determined that the dominant source of lead ions in the aqueous solution was $Pb(OH)^+$ at a pH of 8, which was conducive to the adsorption and interaction of SHA and ADDP anions. In the lead ion activation system, the combined reagent co-adsorbed onto the TNO surface, causing a large negative shift in the zeta potential. The co-adsorption mechanism of the combined collector consisted of complex chemisorption between SHA and the TNO surface active particles, while the main adsorption of ADDP is physisorption.
Źródło:
Physicochemical Problems of Mineral Processing; 2021, 57, 1; 29-38
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Activation of quartz flotation by Cu2+, Ni2+ in the sodium ethylxanthogenate (EX) system
Autorzy:
Liu, Yang
Tong, Xiong
Xie, Rui-Qi
Xie, Xian
Song, Qiang
Fan, Pei-Qiang
Powiązania:
https://bibliotekanauki.pl/articles/24085981.pdf
Data publikacji:
2023
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
quartz
flotation
ions activation
sodium ethylxanthogenate
adsorption mechanism
Opis:
During the flotation of metal sulfide minerals, due to the interference of unavoidable ions, the quartz also partially floats in some cases. The studies on the mechanism of quartz being activated and floating up are still insufficient. In this study, the influence of the Cu2+ and Ni2+ unavoidable ions on the floatation of quartz was studied by micro-flotation experiments, adsorption detection, zeta potential measurement, solution composition calculation, infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) analyses, and atomic force microscopy (AFM) observation. This provides a theoretical reference for further understanding the mechanism of sodium ethylxanthogenate and quartz surface, as well as the development of a new quartz depressant. The results of flotation showed that after activation by Cu2+ (1×10-4 mol/dm3) and Ni2+ (5×10-5 mol/dm3), the quartz was captured by sodium ethylxanthogenate (EX: 1.4×10-4 mol/dm3) under alkaline conditions (pH=10), while the best recoveries were obtained as 80% and 43%, respectively. The results of adsorption and zeta potential measurements showed that the precipitation rate of Cu2+ was greater than that of Ni2+ under alkaline conditions. Additionally, both Cu2+ and Ni2+ electrostatically adsorbed on the quartz surface and changed the zeta potential of quartz. The solution composition calculation further showed that Cu(OH)+, Cu(OH)2(s), and Ni(OH)+, Ni(OH)2(s) were the main components in the solution under alkaline conditions. The FT-IR and XPS analyses and AFM observations demonstrated that Cu and Ni species adsorbed on O atoms on the quartz surface, providing active sites for EX adsorption, and EX combines with Cu and Ni species on the quartz surface to generate -O-Cu-EX and -O-Ni-EX complexes. Finally, the quartz floated up due to the formation of hydrophobic products and firm adsorption.
Źródło:
Physicochemical Problems of Mineral Processing; 2023, 59, 2; art. no. 166368
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Adsorption behavior of calcium ions and its effect on cassiterite flotation
Autorzy:
Chen, Yumeng
Feng, Dongxia
Tong, Xiong
Powiązania:
https://bibliotekanauki.pl/articles/110731.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
cassiterite
calcium ions
adsorption
flotation
salicylhydroxamic acid
Opis:
Naturally, most of the cassiterite co-exists with sparingly soluble calcite, which makes it difficult to be fully utilized. Due to the adsorption of calcium ions dissolved from calcite, surface properties of cassiterite and its floatability can be influenced. Adsorption tests show calcium ions can adsorb on cassiterite surface. In the presence of Ca2+, the zeta potentials of cassiterite shift to more positive values and the isoelectric point of cassiterite increases from pH 4.4 to pH 4.9. XPS results show that after calcium ions treatment, a strong calcium spectral peak at 347.65 eV is detected on the cassiterite surface and the chemical circumstance of oxygen atoms is changed. The presence of Ca2+ can significantly depressed the flotation behavior of cassiterite with salicylhydroxamic acid (SHA) as collector. Its recovery is decreased by 26.03% compared to that without Ca2+ at SHA dosage of 8.0×10-4 mol/dm3. When increasing SHA concentration to 9.0×10-4 mol/dm3 and above, the depression effect is partly compensated and the recovery rises by about 20%. Contact angle values of cassiterite measured by the bubble method correspond well to the flotation performance. Hence the depression mechanism of Ca2+ in cassiterite flotation can be interpreted in two aspects: 1) the consumption of SHA due to complexation reactions in pulp; 2) a decrease of effective adsorption site for SHA on cassiterite because of the adsorption of Ca2+.
Źródło:
Physicochemical Problems of Mineral Processing; 2019, 55, 1; 258-267
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Adsorption kinetic, equilibrium and thermodynamic investigations of Zn(II) and Ni(II) ions removal by poly(azomethinethioamide) resin with pendent chlorobenzylidine ring
Autorzy:
Kumar, P. S.
Ethiraj, H.
Venkat, A.
Deepika, N.
Nivedha, S.
Vidhyadevi, T.
Ravikumar, L.
Sivanesan, S.
Powiązania:
https://bibliotekanauki.pl/articles/780002.pdf
Data publikacji:
2015
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
adsorption
models
Ni(II) ions
poly(azomethinethioamide)
Zn(II) ions
Opis:
This paper reports the application of poly(azomethinethioamide) (PATA) resin having the pendent chlorobenzylidine ring for the removal of heavy metal ions such as Zn(II) and Ni(II) ions from the aqueous solutions by adsorption technology. Kinetic, equilibrium and thermodynamic models for Zn(II) and Ni(II) ions adsorption were applied by considering the effect of contact time, initial metal ion concentration and temperature data, respectively. The adsorption influencing parameters for the maximum removal of metal ions were optimized. Adsorption kinetic results followed the pseudo-second order kinetic model based on the correlation coefficient (R2) values and closed approach of experimental and calculated equilibrium adsorption capacity values. The removal mechanism of metal ions by PATA was explained with the Boyd kinetic model, Weber and Morris intraparticle diffusion model and Shrinking Core Model (SCM). Adsorption equilibrium results followed the Freundlich model based on the R2 values and error functions. The maximum monolayer adsorption capacity of PATA for Zn(II) and Ni(II) ions removal were found to be 105.4 mg/g and 97.3 mg/g, respectively. Thermodynamic study showed the adsorption process was feasible, spontaneous, and exothermic in nature.
Źródło:
Polish Journal of Chemical Technology; 2015, 17, 3; 100-109
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Adsorption kinetics of fluoride on bone char and its regeneration
Autorzy:
Hu, J.
Wu, D.
Rao, R.
Liu, R.
Lai, W.
Powiązania:
https://bibliotekanauki.pl/articles/206892.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
chlorine compounds
fluorine compounds
ions
sodium compounds
sulfur compounds
adsorption kinetics
chemical reaction equilibrium
correlation coefficient
Freundlich equation
optimal conditions
layered double hydroxides
aqueous-solution
drinking water
equilibrium
adsorbent
związki chloru
związki fluoru
jod
związki sodu
związki siarki
kinetyka adsorpcji
równowaga reakcji chemicznej
współczynnik korelacji
równanie Freundlicha
woda pitna
równanie Langmuira
Opis:
The adsorbent of bone char (BC), produced from the pyrolysis of crushed animal bones, was dominated by the mesopores of the Brunauer Emmett Teller (BET) surface area. The optimal condition for defluoridation with BC was a pH level near 5.0. Chloride and nitrate ions could increase fluoride adsorption capacity in contrast with the effect of sulfate and carbonate ions. The interchangeability between fluoride and hydroxyl groups on BC sorbent was proved by the Fourier transform infrared spectroscopy. Langmuir equation had a better correlation coefficient than the Freundlich equation at various temperatures. Thermodynamic parameters such as Delta G degrees, Delta H degrees, Delta S degrees, Ea and S*, have been calculated to describe the nature of fluoride adsorption onto BC. Negative Delta G degrees and Delta H degrees values at various temperatures indicate a spontaneous process, and its exothermic effect, respectively. However, a positive Delta S degrees value represents an increasing process for entropy. The E-a and S* values ranging from 5 to 40 kj.mol-1 and 0 to 1, respectively, demonstrated that the adsorption is dominated by physical process, although the adsorption kinetic process was involved external diffusion, intraparticle diffusion and chemical reaction equilibrium stage. A high concentration of NaOH solution increases efficiency of removing adsorbed F- ions from the BC surface.
Źródło:
Environment Protection Engineering; 2017, 43, 3; 93-112
0324-8828
Pojawia się w:
Environment Protection Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Adsorption method of purification of stocks from chromium(III) ions by bentonite clays
Autorzy:
Soloviy, Christina
Malovanyy, Myroslav
Palamarchuk, Olga
Trach, Iryna
Petruk, Halyna
Sakalova, Halyna
Vasylinych, Tamara
Vronska, Nataliya
Powiązania:
https://bibliotekanauki.pl/articles/1844378.pdf
Data publikacji:
2021
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
adsorption
bentonite
chromium ions
environmental safety
natural clay sorbents
wastewater purification
Opis:
The process of sorption of chromium(III) ions with a stationary sorbent layer of bentonite clays was investigated. The main advantages of using bentonites in water purification technologies are described: powerful geological reserves, cheap process of rock extraction, easy preparation for transportation and use, possibility of using waste sorbents in other technologies that is why there is no need in costly regeneration. The influence of various factors (process duration, an adsorbent layer) on the degree of wastewater purification from chromium ions, the effect of pumping speed on the dynamic capacity of the sorbent was studied and the effective volume was determined. The adsorption efficacy increases with the increase of the adsorbent layer, what can be explained by the development of the active sorption surface. As the initial concentration of chromium ions increases, the time of appearance of the first traces of the contaminant at the exit of the column increases, as well as the total time to channeling. The results of the studies indicate a higher adsorption capacity of modified bentonite with respect to Cr3+ ions compared to its natural formula. The cleaning efficacy of the solution with a concentration of chromium ions of 0.5 g∙dm–3 is increased by 5% when using 15 g of modified bentonite and 6,5% in the case one uses 20 g compared to the natural form.
Źródło:
Journal of Water and Land Development; 2021, 48; 99-104
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Adsorptive purification of aqueous solution from fluoride ions by carbonaceous materials
Autorzy:
Gąsior, D.
Powiązania:
https://bibliotekanauki.pl/articles/297619.pdf
Data publikacji:
2016
Wydawca:
Politechnika Częstochowska. Wydawnictwo Politechniki Częstochowskiej
Tematy:
water treatment
adsorption
fluoride ions
carbonaceous sorption materials
uzdatnianie wody
adsorpcja
jony fluorkowe
sorpcyjne materiały węglowe
Opis:
Fluoride is a widely available element and is the 13th on the list of most common elements in nature. Fluorides are present in all environmental components: water, soil, air and living organisms. It finds its way into water as a result of rocks weathering and leaching, as well as precipitation along with gas and dust pollution of anthropogenic origin. In more and more areas of Poland exceedances are observed, relative to the maximum permitted levels established for fluoride concentration. The level of environmental pollution by fluoride ions increases along with the development of industrial activity of humans and the widespread use of fluorine compounds in agriculture and dental prophylaxis. Currently fluorine compounds are recognized as one of the most dangerous pollutants, contributing to environmental contamination. Fluoride ions can be removed from aqueous mediums using membrane techniques, adsorption, chemical precipitation, coagulation, electrocoagulation or ion exchange. Using adsorption processes is a very good method for water purification from fluoride ions due to its high effectiveness and simple application. The aim of this paper was to research fluoride ion adsorption statics and kinetics for two commercially available carbon materials: activated carbon (W1) and charcoal (W2). Adsorption tests were conducted in static conditions. Concentrations of fluoride ions in the samples were analyzed using the ion chromatography method. The adsorption kinetic occurred according to the pseudo-secondorder kinetic model. Process equilibrium was achieved after 40 minutes of contact between the adsorbent and the adsorbtive when using W1 and after an hour when using W2. Equilibrium adsorption was described using Freundlich’s equations. Freundlich isotherms were characterized by large correlation coefficients (R2 > 0.92). Adsorption capacities of both materials strongly depended on the pH solution. The highest adsorption capacities for both activated carbon (0.199 mg/g) and charcoal (0.169 mg/g) was observed where the initial pH = 2 and the 20 mg/L fluoride concentration. The efficiency of fluoride ions removal from aqueous solutions depended on the process conditions, the initial fluoride concentration, pH, companion ions presence, for example OH‒. The greatest adsorption efficiency (51.9% for a 5 mg/L initial concentration) was exhibited by charcoal.
Źródło:
Inżynieria i Ochrona Środowiska; 2016, 19, 3; 307-318
1505-3695
2391-7253
Pojawia się w:
Inżynieria i Ochrona Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 250

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