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PL
W piątej i ostatniej części cyklu artykułów na temat identyfikacji włókien do celów konserwatorskich zaprezentowano włókna bawełny oraz włókna celulozowe przetwarzane chemicznie. Podjęta tematyka jest związana zarówno z przemysłem papierniczym, jak i tekstylnym, ponieważ obydwie gałęzie przemysłu wzajemnie korzystały z własnych osiągnięć. W artykule przypomniano ważne wydarzenie, jakim było odkrycie obecności celulozy w tkankach roślinnych. Stało się to przyczynkiem do opracowania metod jej przemysłowego wyodrębniania z drewna oraz opracowania szeregu chemicznych modyfikacji celulozy pozwalających na uzyskanie włókien o nowych cechach użytkowych. Zaprezentowano przykłady wyrobów używanych w przemyśle papierniczym oraz tekstylnym. Szczególne miejsce w artykule zajmuje omówienie bawełny, będącej znakomitym, czystym surowcem do chemicznych modyfikacji celulozy. Omawiając badania mikroskopowe włókien zwrócono uwagę na wygląd mikroskopowy włókien bawełny, bawełny merceryzowanej, wiskozy oraz fibry. Niniejsze opracowanie jest krótką syntezą własnych obszernych doświadczeń zawodowych autorów, jak również próbą streszczenia bardzo obszernych zagadnień historyczno-technologicznych wybranych włókien na bazie celulozy.
EN
In the fifth and final part of the series of articles on fibre identification for conservation purposes, cotton fibres and chemically processed cellulose ibres were presented. The subject matter is related to both the paper and textile industry, because both industries shared their achievements. The article recalls an important fact, which was the discovery of cellulose presence in plant tissues. This became a reason to develop methods for its industrial extraction from wood and to develop a number of chemical modifications of cellulose that allow obtaining fibres with new functional properties. Examples of products used in the paper and textile industry are presented. A special place in the article is dedicated to cotton, which is an excellent, pure raw material for chemical modifications of cellulose. Discussing the microscopic examination of fibres, the attention was paid to the microscopic appearance of cotton, mercerized cotton, viscose and fibre. This study is a brief synthesis of the authors’ own extensive professional experience, as well as an attempt to summarize very extensive historical and technological issues of selected cellulose-based fibres.
EN
Anatase, as an important titanium resource, is attracting more and more attention in research and application. In this study, an efficient process of comprehensively extracting the titanium and other valuable elements from the anatase mineral was proposed. The effect of particle size, stirring speed, initial sulphuric acid concentration, solid-to-liquid ratio, and reaction temperature on the leaching rate of titanium from anatase was investigated. Under appropriate two-stage countercurrent leaching conditions, with the first stage of the liquid-to-solid ratio of 1/3 g/cm3, reaction temperature of 120 °C, initial acid concentration of 11 mol/dm3, residence time of 30 min, stirring speed of 200 rpm, and the second stage of the liquid-to-solid ratio of 1/3 g/cm3, reaction temperature of 200 °C, initial acid concentration of 13 mol/dm3, residence time of 30 min, and stirring speed of 200 rpm, over 99% TiO2, 99% Al2O3, and 97% Sc2O3 were extracted respectively with quartz still remained in the residue. X-ray diffraction, X-ray fluorescence spectrometer, and scanning electron microscopy/energy-dispersive spectroscopy were used to characterize the anatase samples before and after the leaching. Additionally, the leaching kinetics analysis indicated that both acid concentration and temperature were the most significant parameters for the leaching process. And, the titanium leaching reaction rate was controlled by the diffusion of reactants through the residual layer.
EN
This work focuses on the hydrometallurgical processing of EAF steelmaking dust in laboratory conditions. The behavior of calcium under the influence of sulphuric acid as the leaching agent is discussed. Due to calcium presence the acid is continuously consumed, gradually leaching the calcium phase from EAF dust as well as other zinc- and iron-containing phases. A thorough composition analysis of the input sample of EAF dust was performed. A kinetic study of calcium showed that its leaching is a very fast process, but most of the calcium reacting with sulphuric acid is precipitated from the solution in the form of CaSO4∙2H2O. This causes greater sulphuric acid consumption, and therefore it is necessary to study the calcium behavior during processing of EAF dust. This work is narrowed with calcium behavior during leaching of EAF dust in sulphuric acid and effect of calcium to extraction other metals into solution.
5
Content available remote Renowacja żelbetowych konstrukcji komór kanalizacyjnych
PL
Ekspertyza stanu technicznego jednej z komór rozprężnych z pompowni oraz komory zasuw na kolektorze DN800 w Markach wykazała występowanie zjawiska zaawansowanej korozji siarczanowej. Stwierdzono również, że zbrojenie konstrukcyjne uległo odkryciu, a w konsekwencji postępowała jego degradacja. Niezbędne okazało się pilne przeprowadzenie prac naprawczych.
EN
Effects of sulphuric acid and ammonia chloride on muscovite dissolution were studied in acid leaching of vein quartz under elevated temperature and pressure. The leaching processes have been studied in detail by analyzing sources of impurity minerals, optimizing leaching process, analyzing leaching kinetics of Al in muscovite and charactering leaching mechanism of muscovite. The results showed that elements of Al and K mainly occurred in muscovite, and 98.10% or more of muscovite could be removed by acid leaching, while the process had limited influence on the particle size of quartz sand. Leaching of Al in the quartz ore was mainly controlled by chemical reaction. A calcination process and ammonia chloride were used for reducing chemical reaction resistance by damaging crystal structure of muscovite and providing stable acid leaching environment. Combined with the calcination process, muscovite, as a main gangue mineral, was effectively extracted during acid leaching of vein quartz at elevated temperature and pressure.
EN
Extraction times for selected metal cations (Mg2+, Al3+, Zn2+, Cd2+, Cu2+, Ni2+, Co2+, Mn2+, Fe2+ and Fe3+) have been measured using cation-exchanging extractants - Versatic 10 (neodecanoic acid), DEHPA (bis(2-ethylhexyl)phosphoric acid) and Cyanex 272 (bis(2,4,4-trimetylpentyl)phosphinic acid). Data was collected directly by measuring and recording pH of the two phase reaction mixture with maintaining continuity of the aqueous phase. Similarly, the stripping rate of selected cations (Mg2+, Al3+, Zn2+, Cu2+, Ni2+, Co2+) in a sulphuric acid solution was measured. Viscosities of organic phases, saturated with cations, were measured before their stripping. Additionally, the extraction dependence of Mg2+, Al3+, Fe2+ and Fe3+ on pH was measured using Versatic 10 at various concentrations (7.5, 15 and 30 %).
8
Content available remote Próby pozyskania potasu i fosforu z popiołu lotnego z biomasy
PL
W pracy zawarto wyniki badań popiołu lotnego ze spalania biomasy z Elektrowni Połaniec. Poprzednio (1) przedstawiono wyniki badań dotyczących odzysku potasu i fosforu z popiołu za pomocą ługowania wodą w różnych temperaturach i przy różnym czasie ługowania. W publikowanej części przedstawiono wyniki badań odzysku tych pierwiastków za pomocą roztworów kwasu azotowego oraz siarkowego. Przebadano otrzymany produkt i pozostałość po ługowaniu.
EN
Flay ash from industrial combustion of biomass was leached with dild. (10%) H₂SO₄ and HNO₃ to recover K and P. The leaching with HNO₃ was more efficient than with H₂SO₄ and resulted in recovering up to 70.2% K and up to 60.4% P contained in the flue ash.
EN
Copper smelter slag and copper smelter slag flotation tailings were leached using sulphuric acid solutions, without or with the addition of either ferric sulphate or hydrogen peroxide. Copper extraction from the slag was typically found to be twice as high as that from the slag flotation tailings. Hydrogen peroxide was determined to be the best lixiviant. Thus, copper and iron extractions were 63.4% and 48.6%, respectively, when leaching the slag with 3 M H2O2, after 120 minutes of reaction at room temperature. Copper dissolution was generally found to be the dominant process within the first 60 minutes of reaction, whereas iron dissolution dominated afterwards.
EN
An experimental study on leaching of cobalt and nickel from a Lubin (Poland) sulfide flotation copper concentrate with oxygenated sulphuric acid solution in the presence of iron(III) sulfate is presented. The effect of temperature, iron(III) concentration, initial sulphuric acid concentration, oxygen flow rate and chloride ions addition on cobalt and nickel leaching were examined. The obtained results show, that enhancing investigated leaching parameters increases both the rate and leaching recovery of nickel and cobalt. The effect of iron(III) ions concentration is particularly significant. Additionally, a significant correlation between copper and nickel/cobalt leaching recovery was observed. Due to the fine dissemination of nickel and cobalt, they were leached remarkably faster when copper leaching recovery exceeded 90%.
EN
The leaching kinetics and mechanism of priceite having the formula of 4CaO5B2O37H2O was investigated in sulphuric acid solutions. For the dissolution process, the effects of reaction temperature, sulphuric acid solution concentration, solid/liquid ratio, particle size, and stirring speed were investigated as effective parameters for the experiments. The experimental data indicated that the dissolution rate increased with the increasing reaction temperature, the decreasing particle size, and the solid/liquid ratio. The conversion rate increased up to 1.0 mol/dm3 with the increasing acid concentration, and then decreased with the increasing acid concentration over concentrations of 1 mol/dm3. It was also determined that the stirring speed had no significant effect on the dissolution rate. The dissolution process of priceite in sulphuric acid solution was tested with regard to heterogeneous and homogeneous reaction models, and it was found that the dissolution rate was controlled by first order pseudo-homogeneous reaction model. The activation energy of the dissolution process was determined as 26.07 kJmol-1. The results were evaluated graphically and statistically. The experimental data were found to fit well with the mathematical model.
EN
The article presents the effect of the addition of polymer to mortars with CEMI and its influence on durability under conditions of sulfuric acid or nitric and sulphur bacteria or nitrogen (nitrification and denitrification). Both acids corresponds to the products of metabolism of bacteria Acidithiobacillus thiooxidans and Thiobacillus denitrificans, Paracoccus denitrificans by the literature is about 0.15 mmol/dm3. The changes in tightness materials studied by determining moisture mass and absorption. Corrosion processes were identified by examination in a scanning microscope equipped with an X-ray microanalyzer and a mercury porosimeter. The research results presented showed that the solution has a significantly weaker effect on the composite cement and cement-polymer compared with the action of bacteria. The action of both environments caused two opposing processes: unsealing the structure and deposition of corrosion products.
PL
Metoda polega na wyodrębnieniu frakcji torakalnej mgły kwasu siarkowego(VI) na filtrze celulozowym z zastosowaniem próbnika umożliwiającego rozdzielenie cząstek frakcji toraklanej, zgodnie z konwencją tej frakcji określonej w normie PN EN 481, następnie ekstrakcji analitu wodą i analizie otrzymanego roztworu metodą chromatografii jonowymiennej. Oznaczalność metody wynosi 0,01 mg/m3.
EN
This method is based on separation thoracic fraction of sulphuric acid on membrane filter fiber placed in PPI sampler. Sulphuric acid is eluted using 30 ml of destillated water. The obtained solution is analyzed with IC with conductometry detection. The working range is 0.01 to 0.1 mg/m3 for a 480 l air sample.
14
Content available remote Otrzymywanie kryształów gipsowych i anhydrytowych o pokroju iglastym
PL
Znana metoda celowego pozyskiwania włókien gipsowych, opierająca się na zasadzie krystalizacji w roztworze schładzanego kwasu solnego, może zostać zastąpiona metodami lepiej uzasadnionymi technologicznie. Kwas solny może zostać zastąpiony kwasem siarkowym, tworzącym typowe środowisko przy pozyskiwaniu gipsów chemicznych. Alternatywnie metodę krystalizacji można zastąpić wymagającymi mniejszych nakładów energetycznych metodami rekrystalizacyjnymi, z udziałem domieszek modyfikujących. Dodatkową zaletą metody rekrystalizacji w roztworze kwasu siarkowego jest możliwość pozyskiwania również iglastych kryształów anhydrytowych.
EN
Well-known method of gypsum fibres obtaining based on crystallisation in cooled hydrochloric acid solution can be replaced with better technologically reasonable methods. Hydrochloric acid can be substituted by sulphuric acid creating typical environment for chemical gypsum obtaining. Alternatively, crystallisation method can be replaced with requiring less energy consumption recrystallisation methods with addition of modifying additives. Further advantage of recrystallisation in sulphuric acid solution method is possibility of receiving also needle-shaped anhydrite crystals.
EN
Results of atmospheric leaching of copper sulphide concentrate from Lubin Concentrator (ZWR Lubin) with oxygenated aqueous H2SO4 and in the presence of Fe(III) have been presented. It was found that oxidative atmospheric leaching performed in acidified and oxygenated iron(III) solutions has to be preceded by a controlled, non-oxidative decomposition of acid-consuming carbonate components in order to further liberate finely disseminated metal-bearing minerals. Atmospheric leaching appeared to be a very efficient process for recovering Cu, Zn, Co and Ni from the Lubin concentrate due to favorable mineralogical composition and fine size of leached particles. A maximum recovery of Cu (95%), Zn (90%), Ni (40%) and Co (50%) was observed after 5-7 hours of leaching at 90C in the oxygenated solutions containing 20-30 g/dm3 of Fe(III). The solid residue after atmospheric leaching will be further processed by flotation or chloride leaching to recover Ag, Pb and precious metals.
PL
Scharakteryzowano odpady przemysłowe powstające w produkcji kwasu siarkowego, omówiono negatywny ich wptyw na środowisko, wskazano kierunki i metody skutecznego ograniczania wielkości tych odpadów i eliminowania ich niekorzystnego wpływu na ekosystem.
EN
Industry wastes from sulfuric acid production were characterized, negative influence on environment, directions and methods ol wastes dimension effective limitation and elimination of theirs unfavorably influence on ecosystem were pointed.
EN
In this work, the process of the subsequent intercalation of HSO4H2SO4 into CrO3-GIC examined. CrO3GICICs are prepared with two different chemical methods: this is, intercalation from the CrO3/CH3COOH solution according to the Platzcr and de la Martiniere procedure and intercalation of CrO3 from Cr03/HCl solution. Furthermore, the preparation of graphite multiintercalation compound consisted with two different intercalates CrO3 and ZnCl2 from the mixture of graph ite/CrO32 HC1 was performed. The intercalation process of both intercalates CrO3 and ZnCl2 into graphite has been confirmed by cyclic voltammetric technique. Upon the successive intercalation of HSO4/H2S04 the anodic and cathodic effects characteristic for the presence of ZnCl2 and CrO3 have been served in the voltammogram. This suggests the formation of quaternary CrO3/ZnCI2-H2SO4-GIC.
PL
Przedstawiono proces biinterkalacji Hsub>2S04 zachodzący w CrO3IZG. Interkalacja CrO3 w grafit była prowadzona z dwóch mieszanin: grafit/Cr03/HCl oraz grafit/CrO3CH3COOH. Ponadto przeprowadzono próbę jednoczesnej interkalacji dwóch interkalatów CrO3 oraz ZnCl2 celem otrzymania układu multiinterkalacyjnego. Aby stwierdzić czy zaszedł proces interkalacji CrO3 oraz ZnCl2 w grafit, produkt reakcji był badany metodą cyklicznej woltamperometrii w 95 % H2SO4. Na podstawie otrzymanych krzywych woltamperometrycznych stwierdzono obecność obu interkalatów (CrO3 oraz ZnCL2 w matrycy grafitowej. Ponadto, w wyniku anodowego utleniania CrOI3ZnCI2-IZG w 95% H2SO4 otrzymano układ poczwórny CrO3/ZnCl2H2SO4- grafit.
EN
The intercalation processes of CrO3 and H2SO4 into ZnCl2-GIC have been confirmed by X-ray diffraction analysis and voltammetric technique. The proposed mechanism of the intercalation of ZnCl2-GIC with CrO3 assumes the formation of co-intercalation domains within the interlayer spacings of the graphite structure. Upon the successive intercalation of the graphite compound with H2SO4, the peaks characteristic of ZnCl2 and CrO3 have been observed in the voltammogram. This is an evidence of the formation of quaternary ZnCl2-CrO3-H2SO4-GIC.
PL
Przedstawiono wyniki badań kinetyki reakcji estryfikacji bezwodnika ftalowego alkoholem etylowym w izotermicznym reaktorze stalowym w obecności kwasu siarkowego jako katalizatora. Doświadczenia przeprowadzono w trzech różnych temperaturach: 373 K, 393 K i 413 K, dla tej samej wartości początkowego stosunku molowego substratów reakcji (bezwodnik-alkohol) równego 1:6. Wartości szybkości reakcji zostały wyznaczone w oparciu o równanie empiryczne aproksymujące dane doświadczalne. Wyznaczone wartości szybkości reakcji po wprowadzeniu do równania kinetycznego pozwoliły określić parametry kinetyczne reakcji. Na podstawie zależności Arrheniusa oraz van't Hoffa wyznaczono energię aktywacji reakcji oraz jej entalpię.
EN
Te esterification kinetics of phthalic anhydride with ethanol was investigated in the isothermal reactor in the presence of sulphuric acid as a catalyst. The investigations were carried out for three different temperatures: 373 K, 393 K and 413 K, within one initial substrate molar ratio (phthalic anhydride-ethanol) equal 1:6. The values of reaction rate have been determined on the basis of empirical equation describing experimental data. The calculated values of reaction rate were introduced into kinetic equation to estimate appropriate parameters. On the basis of Arrhenius and van't Hoff relations activation energy of the reaction and its enthalpy was calculated.
PL
Niezależnie od tego, że produkcja kwasu siarkowego z gazów powstałych po wyprażeniu rud metali nieżelaznych jest ekologiczną koniecznością, należy pamiętać, że proces ten posiada ograniczenia. W artykule przedstawiono uwarunkowania produkcji kwasu siarkowego w Hucie Miedzi LEGNICA wynikające ze specyfiki produkcyjnej, wymogów BAT oraz opisano oddziaływanie emisji przemysłowych na ekosystem.
EN
Although sulphuric acid production from gases released during roasting of non-ferrous metals ores is a must from ecological point of view, some limitations of the process should be emphasised The paper discusses some aspects of sulphuric acid production at the LEGNICA Copper Smelter resulting from specific production conditions and BAT requirements. An impact of the industrial emissions on a local eco-system has been described.
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