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EN
This work presents studies on the recovery of platinum group metals (PGM), especially platinum and rhodium, from spent automotive converters using hydrometallurgical techniques such as leaching and liquid-liquid extraction. The XRD analysis confirmed the presence of indialite – the high temperature hexagonal form of cordierite (the main catalyst building material) in the solid samples. The influence of time and temperature on the leaching of PGM from spent automotive converters was investigated. The largest amounts of Pt(IV) and Rh(III) were leached with freshly prepared aqua regia and a mixture of HCl, HSO4 , and H2O2. Further, liquid-liquid extraction with quaternary phosphonium ionic liquid (Cyphos IL 101) was applied to recover PGM from the leach solutions (after leaching with a mixture of HCl, H2SO4, and H2 O2) and to separate Pt(IV) from Rh(III).
EN
The pretreatment is a key step in the processing of lignocellulosic biomass for its transformation into chemicals and materials of biorenewable origin. Ionic liquids, with their characteristic set of unique properties, have the potential to be the basis of novel pretreatment processes with higher effectiveness and improved sustainability as compared to the current state-of-the-art processes. In this opinion paper, the author provides a perspective on possible processing strategies for this pretreatment with ionic liquids, identifying different advantages as well as challenges to be overcome.
EN
Because of industrialization and modernization, phenomenal changes have taken place in almost all spheres of life. Consequently, the consumption of energy resources and the cases of environmental hazards have risen to an unprecedentedly high level. A development model with due consideration to nature and an efficient utilization of energy sources has become the need of the hour, in order to ensure a sustainable balance between the environmental and technological needs. Recent studies have identified the suitability of ionic liquids (ILs), often labeled as ‘green solvents’, in the efficient utilization of energy resources and activities such as bio-extraction, pollution control, CO2 capture, waste management etc. in an environmentally friendly manner. The advent of magnetic ionic liquids (MILs) and deep eutectic solvents (DESs) have opened possibilities for a circular economic approach in this filed. This review intends to analyze the environmental and energy wise consumption of a wide variety of ionic liquids and their potential towards future.
EN
Co@Co3O4@Nitrogen doped carbon (Co@Co3O4@NDC) composite is synthesized by high temperature carbonization of ionic liquids followed by low temperature thermal oxidation. In the process of high temperature carbonization, cobalt ions are reduced to metallic cobalt, producing Co@Nitrogen doped carbon (Co@NDC). Co@Co3O4 @NDC composite is obtained after low temperature oxidation, in which a part of the metallic cobalt is oxidized to Co3O4. The structural characterizations indicate that the composite is composed of three crystalline phases (carbon, Co and Co3O4). The results of transmission electron microscopy study show that the carbon materials not only coat the Co@Co3O4 nanoparticles, but also form carbon network that connects the Co@Co3O4 nanoparticles. This conductive carbon network is beneficial to improve the electrochemical performance of the composite. The electrochemical test results show that the Co@Co3O4 @NDC composite exhibits excellent electrochemical performance, delivering the discharge capacities of 790 and 304 mAh∙g-1 after 1500 cycles at 5 C and 10 C. This excellent electrochemical performance is due to synergistic effects of Co3O4, cobalt nanoparticles embedded in carbon which has high conductivity, and nitrogen functional groups.
EN
Chitin is the second most abundant polysaccharide on the Earth after cellulose, therefore there is a tangible need for finding new environmentally-friendly solvents for the manufacture of useful forms of that polymer. Ionic liquids have been recently proposed as a possible type of solvent for chitin and cellulose. The possibility of the dissolution of chitin of various origin in six selected ionic liquids was investigated. Chitin samples were characterised by the main characteristic properties: degree of N-acetylation (by FTIR spectroscopy), degree of crystallinity (by WAXS), average molecular weight (by the viscometric method) and physical form. The studies performed allowed to find the optimum chitin-ionic liquid system based on 1-btyl-3-methylimidazolium acetate for the manufacture of chitin fibres by the solution blow spinning method. Final products were characterized by the same set of parameters as the initial materials.
PL
Chityna jest drugim po celulozie polisacharydem na Ziemi, dlatego istnieje namacalna potrzeba znalezienia nowych i przyjaznych dla środowiska rozpuszczalników do produkcji użytecznych form tego polimeru. Niedawno ciecze jonowe zostały zaproponowane jako możliwe do zastosowania „zielone” rozpuszczalniki chityny i celulozy. W artykule oceniono możliwość rozpuszczania różnego pochodzenia chityny w sześciu wybranych cieczach jonowych. Próbki chityny zostały scharakteryzowane poprzez następujące właściwości: stopień N-acetylacji (spektroskopia FT IR), stopień krystaliczności (WAXS), średnia masa cząsteczkowa (metoda wiskometryczna). Przeprowadzone badania pozwoliły na znalezienie optymalnego systemu cieczy jonowej do wytworzenia włókien chitynowych metodą rozdmuchu. Produkty końcowe zostały scharakteryzowane poprzez ten sam zestaw parametrów, co początkowe polimery.
EN
An aryl-substituted aromatic acid ionic liquid (M-X) was synthesized through hexadecyl trimethyl ammonium bromide and sodium salicylate, and it was employed as a flotation collector for the separation of quartz from magnetite. Laboratory flotation studies of magnetite and quartz were conducted using the M-X and dodecylamine (DDA) as collector. The results showed that the M-X has a stronger collecting ability and selectivity for quartz without starch. The adsorption mechanism of M-X on quartz and magnetite surfaces was studied by Fourier transform infrared spectroscopy (FTIR), zeta potential and X-ray photoelectron spectroscopy (XPS) analysis. Results indicated that the adsorption of M-X on the quartz surface was more efficient than that on the magnetite surface. And the salicylate anion in M-X was found to have depression effect to magnetite.
EN
Results of the investigations on electrodepositon of zinc, copper and copper-zinc alloy coatings from the galvanic baths based on 2-hydroxyethyl- trimethylammonium acetate have been presented in the paper. An influence of cathodic current density on structure of the deposits (SEM) was determined. Moreover, a chemical composition (EDS) as well as a phase composition (XRD) of the obtained alloy coatings were analysed. On the basis of the realized studies it was found that the current conditions influence on grain size of zinc coatings, however in the case of Cu and Cu-Zn coatings the effect is unessential. The electrodeposited brass alloys were solid solutions of zinc in copper.
PL
W pracy przedstawiono wyniki badań nad elektroosadzaniem powłok cynkowych, miedzianych i stopowych Cu-Zn z kąpieli galwanicznych opartych na octanie 2-hydroksyetylo-(trimetylo)amoniowym. W ramach pracy określono wpływ katodowej gęstości prądu na strukturę osadzonej powłoki (SEM). Ponadto wykonano analizę składu chemicznego (EDS) oraz składu fazowego (XRD) wytworzonych powłok stopowych. Na podstawie przeprowadzonych badań stwierdzono, że warunki prądowe wpływają na rozmiar ziaren powłok cynkowych, jednakże w przypadku powłok Cu i Cu-Zn wpływ ten jest nieznaczny. Powłoki mosiężne osadzone elektrolitycznie stanowiły roztwór stały cynku w miedzi.
PL
Technika mikroekstrakcji do pojedynczej kropli jest na etapie przygotowania próbki doskonałym rozwiązaniem technicznym, które spełnia wymagania stawiane przez ideę zielonej chemii analitycznej.
EN
In reversed-phase liquid chromatography, in case of the absence of additives, cationic basic compounds give rise to asymmetrical and broad peaks as a result of interactions of analyte cations with residual free silanols on silica-based stationary phases. Ionic liquids, added to the mobile phase, have been suggested as alternatives to amines to block the activity of free silanols. The different parameters affecting the retention behavior, symmetry of peak, system efficiency, and separation selectivity of selected psychotropic drugs, especially the effect of concentration of ionic liquid, kind and concentration of organic modifiers of mobile phases, and kind of stationary phases were investigated. The most selective and efficient systems are used for separations of psychotropic drug standards' mixture and for determination of selected psychotropic drugs in human serum.
EN
This article reports the results of the study of an a-C:H:Si coating doped with silicon and produced by chemical deposition (PACVD). The effect of the coating on the tribological behaviour of IL-lubricated friction pairs was evaluated. The properties of the 100Cr6 steel specimens with and without the coating were compared. Scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analysis were used for imaging the morphology of the coating surfaces and cross-sections and for identifying the elements in the coating composition. The contact angle of the investigated surfaces was measured with an optical tensiometer. Friction tests were performed on a ball-on-disc tribometer under dry friction and when lubricated with trihexyltetradecylphosphonium bis(trifluoromethylsulfonyl) amide ionic liquid. The geometrical structure of the surfaces before and after the tribological tests was measured using an optical profilometer. The ionic liquid used with the silicon-doped diamond-like coating under friction conditions reduced the coefficient of friction and wear. The results obtained from the tests and analysis allow for the conclusion that the use of DLC coatings a-C:H:Si lubricated with trihexyltetradecylphosphonium Bis(trifluoromethylsulfonyl) amide contributes towards the improvement of tribological properties of sliding surfaces under friction.
PL
Artykuł poświęcony jest badaniom powłoki diamentopodobnej domieszkowanej krzemem typu a-C:H:Si uzyskanej w procesie chemicznego osadzania z fazy gazowej wspomaganego plazmą PACVD. Ocenie poddano wpływ powłoki na właściwości tribologiczne węzłów tarcia smarowanych cieczą jonową (Ionic Liquid) IL. W analizie porównano próbki ze stali 100Cr6 bez powłoki oraz pokryte powłoką diamentopodobną. Przy użyciu skaningowego mikroskopu elektronowego SEM (Scanning Electron Microscopy) wyposażonego w mikroanalizator rentgenowski EDS (X-ray Energy Dispersive Spectroscopy), zobrazowano morfologię powierzchni powłok, ich przekroje poprzeczne oraz dokonano identyfikacji pierwiastków wchodzących w skład powłoki. Wykonano również pomiary kąta zwilżania badanych powierzchni na optycznym tensjometrze. Badania tarciowe przeprowadzono na tribotesterze pracującym w skojarzeniu trącym kula–tarcza w warunkach tarcia technicznie suchego oraz z zastosowaniem smarowania cieczą jonową triheksyltetradecylphosphonium bis(triffluoromethylsulfonyl) amide. Charakterystykę struktury geometrycznej próbek przed oraz po badaniach tribologicznych przeprowadzono na profilometrze optycznym. Wyniki badań wskazały, że użyta ciecz jonowa w skojarzeniu trącym z powłoką diamentopodobną domieszkowaną krzemem wpłynęła na zmniejszenie współczynnika tarcia oraz zużycia. Otrzymane wyniki wskazują, że zastosowanie powłok diamentopodobnych typu a-C:H:Si smarowanych triheksyltetradecylphosphonium bis(triffluoromethylsulfonyl) amidem sprzyja poprawie właściwości tribologicznych węzłów tarcia w ruchu ślizgowym.
PL
Celem badań było uzyskanie kompozytów z kauczuku butadienowo-styrenowego (SBR) o polepszonych właściwościach użytkowych, obniżonej temperaturze i skróconym czasie wulkanizacji. Jako aktywator wulkanizacji zastosowano nanometryczny tlenek cynku zmodyfikowany cieczą jonową w masie elastomeru lub w rozpuszczalniku. Aplikacja takiego układu aktywującego pozwoliła uzyskać wulkanizaty o zwiększonej wytrzymałości na rozciąganie, twardości i odporności na starzenie termo-oksydacyjne w stosunku do zawierających mikrometryczny ZnO. Czas wulkanizacji uległ skróceniu, a temperatura i entalpia procesu zmniejszyły się. Uzyskano wulkanizaty o 50% mniejszej zawartości ZnO, zgodnie z Dyrektywą Unii Europejskiej.
EN
The main aim of research was to obtain elastomer composites of styrene-butadiene rubber (SBR) with improved functional properties, reduced temperature and time of vulcanization. Nanosized zinc oxide modified with ionic liquid directly in the elastomer matrix or in the solution process was used as vulcanization activator. Application of this activating system resulted in vulcanizates with increased tensile strength, hardness and resistance to thermo-oxidative aging as compared with microsized ZnO activator. The vulcanization time of SBR, the temperature and enthalpy of this process were reduced. The vulcanizates with 50% lower content of ZnO were obtained, according to the EU Directive.
12
Content available Perspective polyionens with special properties
EN
New polyionens based on epoxy derivatives of 1,2-epoxy-4,7-dioxononen-8 and tetrahydro-1, 4-oxazine were synthesized. The basic regularities of polyionen synhthesis were established. Systematic study of the physico-chemical, optical, thermal and viscosimetric properties of new polyionens was carried out. It was found that the obtained polyionens are capable of operating in the range from -54 to 140°C. The ionic conductivity of synthesized polyionens are 10-2-10-4 Cm cm 2. Thus, the studied polyionens can be recommended for use as a component of liquid, polymeric lithium electrolytes, solar cells, condensers, as effective additives for cellulose triacetate compositions, as coagulants in the treatment of sewage.
EN
The paper presents the results of research on the preparation and use of cellulose granules as carriers of nutrients in the cultivation of plants. The granules were prepared from a cellulose solution in 1-ethyl-3-methylimidazole acetate followed by coagulation in water and primary alcohols: methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol and 1-octanol. Modifications of granules were also carried out by hydrophobization at elevated temperature and by encapsulation in a polylactide solution. As a result of the research, cellulose granules were obtained, which were characterized by different porosity, depending on the type of coagulant used. The morphology of granules surface and cross-sections was examined by means of scanning electron microscopy (SEM). The cellulose granules exhibited good sorption/desorption properties which were investigated by conductometry and UV-Vis spectroscopy. The longest desorption time of NH4NO3 was characteristic of granules obtained as a result of thermal hydrophobization of the surface, which were used in the cultivation of the spider plant. As a result of the research, cellulose granules were obtained which may find potential application in crop production, as long-acting, non-dusting and fully biodegradable fertilizers.
EN
This paper presents the results of studies on the preparation of cellulosic membranes, from a solution in 1-ethyl-3- methylimidazolium acetate (EMIMAc), using the phase inversion method. Initially, the membranes were obtained by coagulation of the polymer film in water and primary alcohols (methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol), 1-hexanol, 1-octanol) resulting in membranes with significantly differing morphologies. Subsequently, composite membranes were produced, with the support layer being a membrane with the largest pores, and the skin layer a membrane with smaller pores. The resulting membranes were tested for physicochemical and transport properties. The morphology of the membrane surfaces and their cross-sections were investigated by using a scanning electron microscope (SEM). The structure of the membranes, on the other hand, was investigated by FTIR spectroscopy and WAXS structural analysis.
EN
The purpose of the study was to evaluate the properties of DLC coatings with ionic liquids used as lubricants. The type a-C: H DLC coatings were deposited onto the 100Cr6 steel substrate by PVD. The surface topography of the DLC coatings was studied with a Bruker's Dimension Icon® Atomic Force Microscope (AFM), and surface morphology testing, cross section and chemical composition analyses were performed using the Jeol JSM-7100F scanning electron microscope, equipped with an EDS microanalyzer. Surface geometry measurements prior to and after tribological tests were performed on a Taylor Hobson's Talysurf CCI contactless optical profilometer. The tribological tests were carried out on an Anton Paar TRB tribotester under technically dry and lubricated friction with an ionic liquid, 1-Butyl-3-methylimidazolium tetrafluoroborate. The results show that DLC coatings and ionic liquids can significantly reduce resistance to motion.
PL
Celem przeprowadzonych badań była ocena właściwości powłok diamentopodobnych DLC smarowanych cieczami jonowymi. Powłoki diamentopodobne typu a-C:H naniesione zostały na stal 100Cr6 za pomocą metody PVD. Wykonano badania topografii powierzchni powłok DLC na mikroskopie sił atomowych AFM – Dimension Icon – Brucker oraz badania morfologii powierzchni, przekrojów poprzecznych oraz analizy składu chemicznego przy użyciu elektronowego mikroskopu skaningowego Jeol JSM –7100F, wyposażonego w mikroanalizator EDS. Pomiary struktury geometrycznej powierzchni przed i po testach tribologicznych wykonano na bezstykowym profilometrze optycznym Talysurf CCI Firmy Taylor Hobson. Testy tribologiczne przeprowadzono na tribotesterze Anton Paar TRB w warunkach tarcia technicznie suchego i tarcia ze smarowaniem cieczą jonową – tetrafluoroboranem 1-butylo-3-metyloimidazoliowym. Przedstawione wyniki badań wykazały, że zastosowanie powłok DLC oraz cieczy jonowej znacznie obniża opory ruchu.
EN
The paper presents results of research on the preparation of cellulose membranes with graphite oxide addition (GO/CEL). Initially, a cellulose (CEL) solution in 1-ethyl-3-methylimidazole acetate (EMIMAc) was obtained, to which graphene oxide (GO) dispersed in N,N-dimethylformamide (DMF) was added. From this solution, composite membranes were formed using phase inversion method. It was observed that the GO addition influences the physico-chemical properties of GO/CEL composite membranes, resulting in an increase in their mass per unit area, thickness and density, and a decrease in sorption properties. In addition, the study of transport properties has shown that GO/CEL membranes do not absorb BSA particles on their surface, which prevents the unfavorable phenomenon of fouling. An important feature of the obtained membranes is the specific permeate flux which reaches high values (~124 L/m2 ×h) at 3.8% of the GO addition to the cellulose matrix.
EN
An ionic liquid-based cloud-point extraction (IL-CPE) method was developed for the extraction of quercetin in juice samples before its determination by high-performance liquid chromatography (HPLC). 1-Butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]) was used as the ionic liquid. The cloud-point extraction parameters such as sample pH, extraction temperature, extraction time, amount of ionic liquid, extraction volume, and salt concentration were carefully studied and optimized for the achievement of maximum extraction recovery. Under the optimized conditions, i.e., 20 min heating at 40 °C, 100 μL IL volume, pH 2.0, and no salt addition, a mean recovery of 92.5% and an enrichment factor of 20 were obtained for quercetin. Relative standard deviation of the method was 3.76% for 6 replicates, and the calculated detection limit (3σ) of quercetin was 0.002 mg L−1. The method, coupled to HPLC was successfully applied to the sensitive determination of quercetin in apple and gapes juice samples with quantitative recoveries.
18
Content available remote Pochłanianie ditlenku węgla w kolumnie wypełnionej zraszanej cieczą jonową
PL
Przedstawiono wyniki badań pochłaniania CO2 w cieczach jonowych [Emim][Ac] i [Bmim][Ac] pod ciśnieniem atmosferycznym, w kolumnie wypełnionej. W badaniach eksperymentalnych określono wpływ zawartości CO2 w gazie wlotowym i temperatury absorpcji na sprawność usuwania CO2 z gazu. Wyniki doświadczalne porównano z obliczeniami wykonanymi na podstawie zaprezentowanego modelu procesu. Badania pokazały, że pojemności sorpcyjne CO2 zastosowanych cieczy jonowych i roztworów amin są porównywalne, jednak w przypadku cieczy jonowych potrzebny jest znacznie dłuższy czas kontaktu (większa powierzchnia wymiany masy) do usunięcia tej samej ilości CO2.
EN
CO2 was absorbed from its mixt. with N2 in 1-ethyl – and 1-butyl-3-methylimidazilium acetates in a lab. Sprinkled column packed with Rashig rings. The applicability of both ionic liqs. for sepn. of CO2 from flue gases instead of NH2(CH2)2OH was confirmed.
EN
In this research work, thermal decomposition and kinetic analysis of pure and contaminated imidazolium based ionic liquid (IL) has been investigated. As thermal decomposition and kinetics evaluation plays a pivotal role in effective process design. Therefore, thermal stability of pure 1-butyl-2,3-dimethylimidazolium chloride (BDMIMCl) was found to be higher than the sample of IL with the addition of 20% (wt.) NH4Cl as an impurity. The activation energy of thermal degradation of IL and other kinetic parameters were determined using Coats Redfern method. The activation energy for pure IL was reduced in the presence of NH4Cl as contaminant i.e., from 58.7 kJ/mol to 46.4 kJ/mol.
PL
W pracy przedstawiono wyniki badań wpływu dodatku wybranych cieczy jonowych do kąpieli stanowiącej roztwór wodorotlenku sodu na strukturę anodowo utlenianych powłok stopowych Zn-Co. Do badań wykorzystano cztery ciecze jonowe zbudowane z tego samego kationu 2-metylopirydyniowego i różnych anionów, tj.: octanowego, trifluorooctanowego, ortofosforanowego(V) i siarczanowego(VI). Do określenia struktury powstających powłok tlenkowych wykorzystano skaningową mikroskopię elektronową. W celu określenia składu chemicznego powierzchni zmodyfikowanej powłoki wykorzystano metodę spektroskopii fotoelektronów (XPS) oraz spektroskopię fluorescencji rentgenowskiej (XRF). Określono także odporność korozyjną metodą potencjodynamiczną (LSV). Na podstawie przeprowadzonych badań stwierdzono, że dodatek wszystkich zastosowanych cieczy jonowych powoduje powstawanie powłok tlenkowych bez widocznych pęknięć. Ponadto, powłoki te wykazują lepszą odporność korozyjną niż te, utlenianie w kąpieli bez dodatku cieczy jonowych.
EN
Results of investigations on effect of selected ionic liquids addition to the baths being solution of sodium hydroxide on a structure of anodically oxidized Zn-Co alloy coatings. Four ionic liquids consisted of the same 2-methylopyridinium cation and different anions, i.e.: acetate, trifluoroacetate, orthophosphate and sulfate were applied in the study. The X-ray photoelectron spectroscopy (XPS) and X-ray fluorescence spectroscopy (XRF) were used in order to determination of a chemical composition of the modified surface. A corrosion resistance by LSV potentiodynamic method was also determined. On the basis of the realized study it was found that the addition of ionic liquids results in formation the oxide coatings without cracks. Moreover, the coatings are characterized by better corrosion resistance that the ones oxidized in the bath without ionic liquid addition.
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