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1
Content available remote Badanie procesu ekstrakcji polisacharydów z Pleurotus geesteranus
PL
Sproszkowany Pleurotus geesteranus poddano ekstrakcji ultradźwiękowej z użyciem wody w celu odzyskania polisacharydów. Wpływ stosunku masy ciała stałego do masy cieczy (stosunek ciało stałe-ciecz), pH, temperatury i czasu działania ultradźwięków na wydajność ekstrakcji badano za pomocą testu jednoczynnikowego i ortogonalnego. Czynniki zostały uporządkowane wg malejącego wpływu na wydajność procesu w szeregu: temperatura > stosunek ciało stałe-ciecz > pH > czas. Optymalne warunki procesu to: stosunek ciało stałe-ciecz 1:20, pH 10, temp. 70°C i czas działania ultradźwięków 5 min. Niepewność powtarzalności wyników wynosiła 0,01301%, 0,0098% i 0,01386%. Współczynnik ekstrakcji polisacharydów z Pleurotus geesteranus wynosił ok. 0,012%.
EN
Pleurotus geesteranus powder was processed by ultrasonic extn. with water to recover polysaccharides. The effects of solid-liq. ratio, pH, temp. and ultrasonic time on the extn. efficiency were studied by single factor and orthogonal tests. The factors were ordered according of decreasing efficiency in series: temp. > solid-liq. ratio > pH > time. The optimum process conditions were: solid-liq. ratio 1:20, pH 10, temp. 70°C, and ultrasonic time 5 min. The repeatability uncertainties of this protocol were 0.01301%, 0.0098%, and 0.01386%. The extn. rate of polysaccharides from Pleurotus geesteranus was about 0.012%.
EN
Addition of organic acids to dilute hydrochloric acid solution can improve the extraction of rare earth elements by single cationic extractants. However, the correlation between the chemical structure of organic acids and the extraction of REEs as well as the variation in equilibrium pH has not been elucidated. In this study, we investigated the extraction of Tb(III) from dilute HCl solutions containing an organic acid like formic, lactic, fumaric, or maleic acid. As extractants, single Cyanex 272, a mixture of Cyanex 272 and Alamine 336 (Ala336-Cy272), and an ionic liquid (ALi-Cy272) synthesized by Cyanex 272 and Aliquat 336 were used. The speciation of Tb(III) in dilute HCl solutions containing organic acids was analyzed. In extraction of Tb(III), organic acids showed two roles as complexing and buffering agent, which depended on the chemical structure of the acids. There was some difference in the extraction of Tb(III) between single Cyanex 272 and ionic liquid, ALi-Cy272. During extraction with ALi-Cy272, formic and lactic acid negatively affected the extraction of Tb(III). The fact that the chemical structure of organic acids affected the extraction of Tb(III) from dilute HCl solution by the studied extractants can provide important information on the selection of suitable extraction systems.
EN
The extraction of light rare earths (Pr and Nd) from chloride medium was investigated using a mixture of di(2-ethylhexyl) phosphoric acid (P204) and bis(2,4,4-trimethylpentyl) phosphinic acid (Cyanex272) in sulfonated kerosene. The P204+Cyanex272 system exerted a synergistic effect on the separation of light rare earths, and the separation coefficient was higher than when P204 and Cyanex272 were used as extractants alone. The separation coefficient of Pr and Nd in the extraction system reached 1.75 when the pH of the aqueous phase material solution was approximately 2.5, and 1.5 mol/L hydrochloric acid as a stripping agent effectively eluted the rare earth ions in the loaded organic phase. Combining the slope method, infrared spectroscopy, and nuclear magnetic resonance spectroscopy, we explored the mechanism of the extracted Nd and Pr into the organic phase complex, and finally entered the organic phase with Re(HA2)2B. The P-O-H bond and P=O bond in the extractant P204 and Cyanex272 formed a coordination bond with Re3+. Therefore, this extraction method also provides a reference for a more environmentally friendly and efficient procedure for separation and purification of light rare earth elements Pr and Nd.
EN
Every year, the production of industrial phosphoric acid generates more than 100 Tg of phosphogypsum (PG), leading to significant environmental damage and the occupation of a vast amount of land space. The urgent need to explore applications for PG has become increasingly apparent. However, impurities such as organic substances, slime, phosphorite, and SiO2 reduce the whiteness of PG, making it difficult to utilize for high-value applications. To address this issue, this study employed a two-stage flotation process to remove the majority of impurities, including SiO2, organic substances, and fine slime adhered to the surface of PG particles. The raw PG sample was first sieved to remove some SiO2 particles. After flotation, sulfuric acid and tributyl phosphate were introduced to decompose the PG particles and remove the impurities wrapped inside. Following this flotation combined extraction process, the whiteness of the PG sample improved from 54.1% to 92.9%, meeting the requirements for building walls and filters.
PL
Neonikotynoidy to insektycydy powszechnie występujące w środowisku oraz w żywności. W artykule opisano podstawowe metody ich ekstrakcji z różnych matryc oraz identyfikacji i analizy ilościowej przy użyciu techniki LC-MS/MS. Omówione zostały także podstawowe problemy w analizie obejmujące niskie stężenia związków, wpływ matrycy na wyniki, a także ograniczenia związane z jonizacją tych substancji.
EN
Neonicotinoids are insecticides commonly detected in the environment and in food samples. The article describes the most common methods of their extraction, identification and quantitative analysis using the LC-MS/MS approach. Difficulties in analytical procedures, including very low concentrations of analytes, matrix effects and limited ionisation in ESI-MS are also briefly discussed.
6
Content available remote Improving the technology of obtaining humic substances from peat
EN
The study of the extraction of humic substances from peat is considered in the work. During the studies of various mode parameters of extraction, the optimal one was determined, which obtained a higher yield of humic substances. For decades, the arguments of plant growers about which forms of fertilizers are more useful for soil fertility and more effective for plants - organic or mineral - have not subsided. Each of these types has its own disadvantages and advantages, and as it turned out later, it is possible to keep the soil healthy and get the maximum benefit only with a competent combination of them.
EN
The olive mill wastewater, effluents from the trituration of olives, are treated in most Mediterranean countries by natural evaporation. However, this method of treatment is a source of air and soil pollution by the generation of solid waste, called olive mill waste cake. This work focused on extracting of vegetable oil from this by-product for biodiesel production by transesterification. The extraction took place with a Soxhlet extractor, using hexane as solvent. The vegetable oil and biodiesel were characterized by measuring the physicochemical parameters that identify them according to AFNOR standards. The extraction results show that the oil yield is 21.28%. The oil obtained is characterized by density, water and ash content, acidity, saponification, peroxide and ester. The yield of the oil esterification reaction is 86.41% or about 185 Kg of biodiesel/ton of olive mill waste cake, and in terms of energy 2783.7 MJ or 2 GW.t-1. The biodiesel produced is comparable to petroleum diesel according to EN 14214, 2013.
EN
It is necessary to find innovative ways to improve the environmental performance of production processes and products. The technology of extracting valuable components from raw materials of plant origin is often used in technological processes of the food, pharmaceutical, chemical and other industries. Extraction is the most energy intensive step. The factors contributing to the extraction of humic acids from plant substrates under the action of electric discharge were studied. The purpose of the work was to study the efficiency of humic acids extraction from the biosubstrate under the action of electric discharges. The physical experiment showed that the main factor influencing the intensity of extraction is the degree of grinding of the solid phase of the biosubstrate-water suspension. The efficiency of electric discharge grinding depends on the pressure amplitude at the distance of the inner radius of the chamber and the number of discharge pulses. It was established that the number of chemical reagents (alkalis), usually used in the process of extracting humic acids from peat, can be reduced many times due to the appearance of radicals and peroxide compounds in the peat-water suspension resulting from the action of an electric discharge. The prospects of the non-thermal electric discharge method of intensification of the extraction of humic acids from biosubstrates were determined.
EN
The study was aimed to evaluate the impact of extraction solvent on the phenolic content, total flavonoids content, and the antioxidant activities of acetonic, methanolic, and aqueous extracts of two lichen species: Evernia prunastri and Ramalina lacera collected from trunks of Argania spinosa using the ultrasound assistance extraction. Various in vitro antioxidant assays were utilized such as 2,2-diphenly-picryly-hydroxyl free radical (DPPH) assay, and ferric reducing antioxidant power (FRAP) assay. All tested samples exhibited a good antioxidant activity, for the DPPH assay, the inhibition percentage ranged from 85±0.2% to 27±0.01%, the phenolic content ranged from 13.17±0.5 mgGAE/g DW to 3.31±0.3 mgGAW/g DW, and flavonoids ranged from 5.84±0.03 mgRE/g DW to 0.01±0.03 mgRE/g DW. This study demonstrates that the extraction solvent has a significant influence on lichens phenolic compounds and on their antioxidant activity, also showed that flavonoids contents are significantly correlated to antioxidant activity of studies lichens; moreover, it shows that ultrasound extraction in a good method to extract the lichens compound. This study suggests that lichens Ramalina lacera and Evernia prunastri could be utilized as natural antioxidant source.
EN
In this case study we compared the fertiliser properties of an industrial wastewater treatment sludge and a sludge ash to the requirements of the Finnish Fertiliser Product Decree. The sludge was obtained from the activated sludge wastewater treatment plant of a Finnish non-integrated pulp mill. The sludge was furthermore incinerated at a laboratory in a muffle furnace (850 °C) to obtain sludge ash. The total Cd (4.9 mg/kg d.m.) concentration in the pulp sludge exceeded the Finnish limit value (1.5 mg/kg d.m.) for fertiliser products used in agriculture. In the sludge ash, the total concentration of Cd (39 mg/kg; d.m.) exceeded the Finnish limit value (25 mg/kg d.m.) for ash fertilisers used in forestry. These results restrict the potential reuse options of these residues. However, from the utilisation point of view, the enrichment of essential plant macro-nutrients was most notable, resulting to the following total concentrations of these elements in the sludge ash: P (26,000 mg/kg d.m.), S (40,000 mg/kg d.m.), K (11,000 mg/kg d.m.), Ca (83,000 mg/kg d.m.) and Mg (10,000 mg/kg d.m.). Therefore, we conclude that, the converting of sludge into ash may promote the reuse of this wastewater treatment residue to a more value-adding fertiliser by-product to be used as a soil improver and growing medium in landscaping or landfills sites or other closed industrial areas, where heavy metal limit values for fertilisers are not applied in Finland.
PL
Pyły by-pass, są odpadami powstającymi w procesie produkcji klinkieru portlandzkiego. Ze względu na duże ilości chloru w pyłach by-pass nie mogą one być ponownie wykorzystywane w procesie produkcji cementu. Producenci nawozów mineralnych dysponują technologią odzyskiwania potasu z pyłu by-pass, podczas której następuje równoczesna ekstrakcja z niego niepożądanego chloru. Z uwagi na dużą zawartość CaO niewęglanowego w pozostałości po ekstrakcji potasu i chloru z pyłu by-pass, materiał ten może być bardzo cennym składnikiem w produkcji klinkieru portlandzkiego. Celem niniejszego artykułu jest przedstawienie możliwości produkcji niskoemisyjnego klinkieru portlandzkiego z wykorzystaniem pozostałości po ekstrakcji potasu i chloru z pyłu by-pass. Zastosowanie maksymalnej ilości pozostałości po ekstrakcji do namiarów surowcowych [zestawów surowcowych], z których produkuje się klinkier portlandzki, zmniejszyło emisję o 407,6 kg CO2 na Mg klinkieru portlandzkiego, w porównaniu do klinkieru portlandzkiego wyprodukowanego z naturalnych surowców węglanowych. Ponadto cementy wykonane z klinkierów wyprażonych z udziałem pozostałości po ekstrakcji wykazały lepsze przyrosty wytrzymałości po 2, 7, 28 i 90 dniach twardnienia, w porównaniu do cementu odniesienia, wykonanego z klinkieru portlandzkiego wyprażonego z udziałem naturalnych surowców węglanowych.
EN
By-pass dusts are waste products formed during the production of Portland clinker. Due to the high amounts of chlorine in by-pass dust, they cannot be reused in cement production. Mineral fertilizer producers have the technology to recover potassium from by-pass dust, during which unwanted chlorine is simultaneously extracted. Due to the high content of non-carbonated CaO in the residue after extracting potassium and chlorine from by-pass dust, this material can be a very valuable ingredient in the production of Portland clinker. This paper aims to present the possibility of producing low-emission Portland clinker using the residue after extracting potassium and chlorine from by-pass dust. Using the maximum amount of extraction residue in the raw material sets from which Portland clinker is produced reduced emissions by 407.6 kg CO2 per Mg of Portland clinker, compared to Portland clinker produced from natural carbonate raw materials. Additionally, cements made from clinkers calcined with extraction residue showed better strength increases after 2, 7, 28, and 90 days of curing compared to reference cement made from Portland clinker calcined with natural carbonate raw materials.
EN
The natural environment is suffering greatly from population growth, industrialization, and waste production. When pavements are to be repaired or reconstructed, the waste material poses a threat as it is landfilled and not used up to its potential. Reclaimed asphalt pavement (RAP) has been gaining importance as there is a depletion of natural resources as well as its potential to perform well if reused or recycled. The extraction and recovery process is carried out to evaluate the properties of the aged binder in RAP. Extraction and recovery need to be coupled with gravitational sedimentation and filtration for the removal of mineral fillers from the aged binder + solvent solution. This study uses Centrifuge extraction and a rotary evaporator for extraction and recovery, respectively. In this study, three different solvents, namely tri-chloroethylene (TCE), toluene, and n-propyl bromide (nPB) are used for the centrifuge extraction. Extraction was followed by gravitational sedimentation and filtration. The results were evaluated by Fourier Transform Infrared spectroscopy (FTIR). Gravitational sedimentation is carried out and samples are tested after 0, 30, 60, 120, 240, and 1440 min by FTIR followed by filtration. In order to assess the properties of aged binder accurately, it should be free from mineral fines. Based on the properties of aged asphalt, percentages of RAP binder and rejuvenator by virgin binder can be evaluated. The results demonstrated that the removal efficiencies were affected by the type of solvent used for extraction.
EN
Wild edible plants (WEPs) can be widely found in the world and defined as native species that grow naturally in their natural habitat. They have become part of the traditional food as human diet and used in folk medicine to treat diseases. They are very rich in terms of nutraceuticals. Melatonin is a natural hormone providing several benefits for human health. It has functions such as regulating growth and development and increasing tolerance to environmental stress factors in plants. It is stated that the serum melatonin level in humans increases after intake of foods containing melatonin. This study examined the presence of melatonin in wild grown cornelian cherry fruits by UFLC-FD and determined suitable extraction and chromatographic conditions. The optimum mobile phase, excitation/emission wavelength, and extraction solvent were determined as methanol: water: acetic acid, 275/345 nm, and methanol: water: HCl, respectively. Melatonin content in fruits ranged from 130.82 to 201.84 ng g⁻¹ in fresh fruit.
EN
Fruits, vegetables and yeast contain numerous biologically active compounds called "phytonutrients". The phytonutrients can include phenolic compounds, minerals and vitamins. Conventional techniques used to extract these nutrients suffer from several disadvantages. These methods are characterized by poor efficiency of the extraction process, high energy and solvent consumption, long processing times and the formation of thermal decomposition by products. For this reason, scientists together with food engineers are looking for a safe and efficient extraction of bioactive compounds. In recent years, several modern techniques to support the extraction process have been proposed. One of them is the pulsed electric field (PEF). Pulsed electric field is one of the non-thermal methods used to control microbiological safety and change the properties (nutritional, sensory and physicochemical) of food products. The principle of operation of PEF is based on the formation of pores in the cell membrane under the influence of short bursts of electricity, which increases its permeability. Due to the formation of pores, various components, such as ions, molecules and other more complex compounds, such as vitamins or lipids, can flow freely through the cell membrane. The use of PEF for extraction reduces the process time, increases the efficiency of the process and is characterized by a low processing temperature. This review shows the use of a pulsed electric field as a process supporting the extraction of biological compounds from algae, vegetables, fruits and in the brewing industry. The optimal conditions of the pulsed electric field, which may affect the extraction efficiency, e.g. electric field strength, number of pulses and pulse width, are also discussed. Based on the collected literature data, it was found that the pulsed electric field contributes to the increase of the extraction efficiency.
PL
W polskim górnictwie węgla kamiennego obserwowana jest od lat 90. XX w. stała tendencja zmniejszania się rocznego wydobycia. Maleje również liczba eksploatowanych ścian, a zawężający się poziom zasobów bilansowych powoduje konieczność sięgania po złoże zalegające w coraz trudniejszych warunkach geologicznych i górniczych. Oznacza to wielokrotnie konieczność projektowania eksploatacji w zasięgu: oddziaływania zaszłości eksploatacyjnych (krawędzi, resztek, filarów) oraz na coraz większych głębokościach. Uwarunkowania te wpływają na poziom aktywności sejsmicznej związanej z prowadzoną eksploatacją. W artykule przedstawiono analizę głębokości eksploatacji prowadzonej w polskich kopalniach węgla kamiennego na tle ogólnego poziomu wydobycia węgla oraz aktywności sejsmicznej generowanej eksploatacją, w obszarach Górnośląskiego i Lubelskiego Zagłębia Węglowego w latach 2005-2020, z interwałem 5-letnim. Wydzielono cztery rejony w GZW, uwzględniając strukturę geologiczną tego obszaru, oraz jeden rejon dla LZW. Poziom zagrożenia sejsmicznego, obrazowany głównie liczbą wysokoenergetycznych wstrząsów górotworu, pomimo spadającego systematycznie wydobycia oraz zmniejszającej się liczby wyrobisk eksploatacyjnych, ma od roku 2005 wyraźną tendencję rosnącą. Ma to swoje uzasadnienie w sięganiu po złoża w trudniejszych warunkach geomechanicznych, w tym przede wszystkim, zalegające na coraz większych głębokościach.
EN
Since the 1990s, the Polish hard coal mining industry has witnessed a steady trend of decreasing annual mining outputs. The number of exploited longwalls is also decreasing, and diminishing balance-sheet resources make it necessary to use deposits that are in increasingly difficult geological and mining conditions. This often means that it is necessary to design mining operations aimed to exploit mining remains (edges, remains, pillars) and go to greater depths for mining. These conditions affect the seismic activity level associated with exploitation. The article presents an analysis of the depth of exploitation conducted by the longwall system against the background of the overall level of coal extraction and seismic activity generated by exploitation, in the areas of Upper Silesian Coal Basin and Lublin Coal Basin in 2005-2020, with 5-year intervals. 4 areas were distinguished, considering the geological structure of Upper Silesian Coal Basin and 1 area for Lublin Coal Basin. The level of seismic hazard, illustrated mainly by the number of high-energy of tremors, despite the systematically declining extraction and the decreasing number of mining excavations, has had a clear growing tendency since 2005. This is justified in reaching for deposits in more difficult geomechanically conditions, including those located at ever greater depths.
EN
The extraction of total Cr(VI) from commercially available cements, based on DTPA + 0.2 mol dm-3 (NH4)2SO4/NH4OH mixture solution and subsequent selective determination of Cr(VI) has been proposed. The determination was carried out using the adsorptive voltammetric stripping method. The study was conducted using three different commercially available cement samples. It has been checked that the proposed extraction procedure guaranteed no changes of chromium speciation during cement analysis. For comparison extraction was also carried out with the use of recommended by United States Environmental Protection Agency (EPA) Method 3060A, based on 0.28 mol dm-3 Na2CO3 + 0.5 mol dm-3 NaOH). Additionally, the extraction process was carried out using only distilled water as an extraction mixture which allows to evaluate concentration of only soluble Cr(VI) forms contained in cement. In all three cements, the content of soluble Cr(VI) was below 2 ppm, i.e. the limit value by European Union Directive 2003/53/EC.
PL
W artykule przedstawione zostały zagadnienia związane z opracowaniem metodyki chromatograficznego oznaczania wielopierścieniowych węglowodorów aromatycznych w próbkach gleb. Do tego celu stosowano chromatograf cieczowy serii Vanquish Core firmy Thermo Scientific wyposażony w detektor fluorescencyjny (FLD) i detektor UV-ViS. W ramach prowadzonych badań określono optymalne parametry pracy chromatografu, takie jak: objętość próbki, rodzaj eluentów, szybkość przepływu eluentów, gradient eluentów w trakcie analizy chromatograficznej i czas analizy, oraz dobrano kolumnę chromatograficzną umożliwiającą selektywny rozdział analitów. Następnie wykonano kalibrację układu chromatograficznego i walidację metody analitycznej oznaczania WWA, stosując roztwory kalibracyjne opracowane na podstawie roztworu wzorcowego PAH-Mix nr ref. 722393 firmy Macherey-Nagel. Walidacja metody analitycznej obejmowała wyznaczenie liniowości, odchylenia standardowego, względnego odchylenia standardowego, granicy wykrywalności (LOD) i granicy oznaczalności (LOQ) badanych WWA. Chromatograficzna metoda identyfikacji WWA w próbkach gleb wymaga przeprowadzenia analitów z matrycy stałej do matrycy ciekłej (etap izolacji), oczyszczenia próbki z substancji przeszkadzających oraz zagęszczenia ekstraktu (etap wzbogacania). W celu opracowania metody oznaczania WWA w próbkach gleb sprawdzono 3 metody przygotowania próbek do analizy chromatograficznej HPLC: metodę A (metoda QuEChERS), metodę B (ekstrakcja rozpuszczalnikiem w aparacie Soxhleta) i metodę C (ekstrakcja rozpuszczalnikiem wspomagana wytrząsaniem). Otrzymane ekstrakty były następnie oczyszczane na wybranym materiale sorpcyjnym: MgSO4 i PSA (metoda A), CN/SiOH (metoda B) i Al2O3 (metoda C). Do przetestowania wybranych metod przygotowania próbek gleby do analizy chromatograficznej HPLC wykorzystano glebę wzorcową PAHs by HPLC40g (SQC017-40G) firmy Sigma Aldrich, o znanych stężeniach analitów. Oczyszczone ekstrakty poddano analizie chromatograficznej HPLC, obejmującej identyfikację oraz ilościowe oznaczenie poszczególnych WWA, oraz obliczono stopnie odzysku analitów. Na podstawie analiz chromatograficznych i stopni odzysku wytypowano optymalną metodykę przygotowania próbek gleb do analizy chromatograficznej pod kątem oznaczania wielopierścieniowych węglowodorów aromatycznych. Opracowaną metodykę oznaczania WWA w próbkach gleb przetestowano na rzeczywistych próbkach gruntu pobranych z 2 otworów badawczych zlokalizowanych na terenie kopalni ropy naftowej usytuowanej w południowo-wschodniej Polsce.
EN
The article presents issues related to the development of a methodology for the chromatographic determination of polycyclic aromatic hydrocarbons in soil samples. For this purpose, a Vanquish Core series liquid chromatograph by Thermo Scientific equipped with a fluores­cence detector (FLD) und UV-ViS detector was used. As part of the research, the optimal parameters of the chromatograph work were determined, such as sample volume, type of eluents, eluent flow rate, eluent gradient during the chromatographic analysis and analysis time, and the chromatographic column was selected to enable selective separation of analytes. Then, the chromatographic system was calibrated and the analytical method for PAH determination was validated using calibration solutions prepared on the basis of the PAH-Mix standard solution ref. 722393 from Macherey-Nagel. The validation of the analytical method included the determination of results linearity, standard deviation and relative standard deviation, as well as limit of detection (LOD) and limit of quantification (LOQ) of the tested method. The chromatographic method of identifying PAHs in soil samples requires the transfer analytes from a solid matrix to a liquid matrix (isolation stage), removal of interfering substances from the sample and concentration of extracts (enrichment stage). Soil samples were tested with 3 methods of sample preparation for HPLC analysis: method A (QuEChERS method), method B (solvent extraction in a Soxhlet apparatus), method C (solvent extraction with shaking). The obtained extracts were then purified on the selected sorption material: MgSO4 and PSA (method A), CN/SiOH (method B) and Al2O3 (method C). Standard soil PAHs by HPLC40g (SQCo17-40g) from Sigma Aldrich with known analyte concentrations was used to test selected methods of preparing soil samples for HPLC chromatographic analysis. The purified extracts were subjected to HPLC chromatographic analysis including identification and quantification of individual PAHs, and the recovery rates of the analytes were calculated. On the basis of chromatographic analyzes and degrees of recovery, the most optimal methodology for preparing soil samples for chromatographic analysis for the determination of polycyclic aromatic hydrocarbons was selected. The developed methodology for determination of PAHs in soil samples was tested on real soil samples collected from 2 boreholes located in an oil mine site in south-eastern Poland.
EN
The principles of sustainable development and green chemistry are priorities in the development of new technologies for the extraction of useful biologically active substances, for example, in the manufacture of medicines. The processes of extracting substances from plant raw materials have many applications. Intensification of such processes, reducing their duration, energy consumption and consumption of the extractant is urgent. The object of the reseach is the green approach to intensify the extraction processes of polysaccharide substances from plant materials. The research methodology was experimental with statistical data processing. In the field of experimental research was the process of the influence of pulsed, alternating and direct current on the intensity of aqueous extraction of polysaccharides from plant materials. The high efficiency of intensification of extraction by a pulsed electric field was studied. The process can reduce the time for obtaining water-soluble polysaccharides by 3 times in comparison with traditional pharmacopoeial convection methods and reduce energy consumption by 20 times. The significance of the pulse current parameters for effective extraction was determined: the referred pulse shape, the frequency of the pulse current for extracting the maximum amount of water-soluble polysaccharides, the pulse duration, and the optimal processing time. The green approach to the use of a moderate electric field of pulsed current to accelerate the extraction of biologically active substances is the basis of the method of intensification of other traditional mass transfer processes for the sustainable development of technology.
EN
Emulsion Liquid Membrane (ELM) has garnered much attention, for its simple operation and high selectivity for the target solute. For an ELM process to be successful, emulsion stability and formulation of liquid membrane are the two main criteria. This study investigated an ELM formulation to identify a suitable green surfactant over the ordinary ones to reduce the utilization of chemicals. The stability of water-in-oil-in-water (w/o/w) was assessed in the following ways, by altering the concentrations of the egg yolk and NaOH, homogenizer speed, and emulsification time. To ascertain the favorable conditions for phenol extraction, several experiments were performed, adopting the batch process, which included many parameters, like the influence exerted by the pH of the external feed, concentration of surfactant, concentration of the internal phase, time of emulsification, homogenization speed and mixing time. Lower breakage and greater extraction efficiency (0.83% and 82.06%, respectively) were attained at 3.5 pH of the external feed, 4% (v/v) of the surfactant, 0.1 M of NaOH, 7 min of emulsification time, 5800 rpm of homogenizer speed and 3 minutes of mixing time. From the results of this study, egg yolk emerged as a good green surfactant. Thus, the ELM process holds promise as an effective technology for stripping phenol from aqueous solutions.
EN
The present study describes a method for the determination of As (III) and As (V) in copper electrolytes. The method is based on the separation of As (III) from a copper electrolyte by triple liquid-liquid extraction using a non-polar organic solvent in a medium of 10-12 mol L-1 HCl. The extract contains As (III) and the raffinate-As (V), respectively. As(III) specie can be re-extracted from the organic solvent through the water. Analyzes of the concentration of As in the re-extract and raffinate were performed by ICP-OES spectroscopic method. The average recovery of arsenic by the proposed method is about 99%. Repeatability was estimated with RSD (n = 6). Selectivity and accuracy were proven by the standard addition method. The relative error for restoring the standard addition of As (III) is about 0.3%. The speciation method analysis could be applied for determination of the arsenic species in the analytical quality control of refined copper in copper tanks in the production of copper cathodes.
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