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Proces utleniającego sprzęgania metanu w obecności różnych gazowych dodatków

Michorczyk B., Ogonowski J., Michorczyk P.

Przemysł Chemiczny

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2015

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T. 94, nr 4

572-575

PL

Przedstawiono informacje dotyczące wpływu dodatków gazowych na przebieg procesu utleniającego sprzęgania metanu. Porównano wpływ dodatku etanu, ditlenku węgla i wody do strumienia reagentów na stopień konwersji metanu, selektywność łączną do węglowodorów C₂₊ (C₂–C₄) i stosunek molowy etylen/etan. Przedstawiono też wyniki badań wpływu dodatków wprowadzanych w śladowych ilościach (chlor, chlorowodór i chlorki alkilowe) na przebieg tego procesu.

EN

A review, with 69 refs., of additives of EtH, CO₂, H₂O, halogens and Cl-contg.

2

2,2’-dihydroksy-1,1’-binaftyl (BINOL) i jego pochodne. Wybrane syntezy i zastosowanie. Część. II

Krasowska D.

Wiadomości Chemiczne

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2013

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[Z] 67, 1-2

55--92

EN

An invention of new catalytic strategies for stereoselective synthesis is of current interest to many laboratories worldwide . Over the past few decades a remark - able progress in the field of stereocontrolled synthesis has been achieved with chiral 1,1’-binaphthyl compounds. Optically active 1,1’-binaphthyl-2,2’-diol (BINOL) and its derivatives due to their axial dissymmetry and molecular flexibility have been widely utilized as chiral ligands and auxiliaries in stoichiometric or catalytic asymmetric reactions, such as metal-catalysed transformations and enantioselective organocatalysis. BINOL and its functionalized analogues have demonstrated remark - able chiral discrimination properties. Extensive studies on molecular recognition provided the successful results in the application of BINOL as a host for an optical resolution of racemic guests and as a chiral NMR shift reagent for the determination of chiral compounds. It has been found that the axial chirality of binaphthyl units in host molecules is crucial contribution to their stereoselctive complexation with chiral guests.

3

2,2'- Dihydroksy-1,1'-binaftyl (BINOL ) i jego pochodne. Wybrane syntezy i zastosowanie. Część I

Krasowska D.

Wiadomości Chemiczne

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2012

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[Z] 66, 5-6

485-528

EN

1,1’-Binaphthyl and its derivatives represent a particular class of chemical molecules which chirality results from the restricted rotation about single bond of the two naphthalene rings. This generates the chirality axis. Therefore 1,1’-binaphthyl derivatives exist as two enantiomeric forms called atropoisomers. Moreover, 1,1’- binaphthyls with substituents at 2,2’ position exhibit higher rotational barriers around the 1,1’-axis, which affect a very stable chiral configuration. The classical examples of such molecules is 2,2-dihydroxy-1,1’-binaphthyl (BINOL ), which has become one of the most utilized chiral ligand and auxiliary for diverse asymmetric syntheses. The unchallenged success of BINOL and its derivatives in the field of transition metal-catalyzed asymmetric reactions or C-C bond forming reactions promoted worldwide an advancement of organic synthesis. The first synthesis of BINOL as racemate was described in 1873. Since then there have been found numerous efficient methods of racemic or enantiomerically pure BINOL preparation and its derivatization. In order to present a brief overview of the most convenient and facile routes to obtain racemic and nonracemic symmetrically substituted 1,1’-binaphthyls based on stoichiometric and catalytic oxidative coupling, classical optical resolution, kinetic enzymatic resolution of racemic mixture or regioselective modification of the binaphthol scaffold the following article is presented.

4

Utleniająca konwersja metanu w obecności O2 i CO2 na wybranych katalizatorach tlenkowych

Litawa B., Michorczyk P., Ogonowski J., Vogt O.

Czasopismo Techniczne. Chemia

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2009

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R. 106, z. 1-Ch

37-42

PL

Zbadano proces utleniającej konwersji metanu wobec mieszanek O2 z CO2 o składzie molowym: CH4:O2:CO2 = 7.5:2:0, 7.5:1.5:0.5, 7.5:1:1 i 7.5:0.5:1.5 w temperaturze 850°C. Do badań wytypowano nośnikowe tlenkowe katalizatory 2Mn/SiO2, 2La/SiO2 lub 5Na2WO4/SiO2 oraz mieszane tlenkowe katalizatory o składzie: 2Mn5Na2WO4/SiO2, 2La5Na2WO4/SiO2, 2La2Mn5Na2WO4/SiO2 (gdzie liczby w zapisie katalizatorów oznaczają udział w % mas. odpowiedniego metalu lub Na2WO4). Stwierdzono, że we wszystkich otrzymanych katalizatorach stopniowe zmniejszanie zawartości O2 w surowcu przez zastępowanie go CO2 wpływa na zwiększenie selektywności do węglowodorów C2 oraz na obniżenie stopnia konwersji metanu. Najwyższy wzrost selektywności do węglowodorów C2 stwierdzono w obecności katalizatora o składzie 2La2Mn5Na2WO4/SiO2.

EN

The oxidative coupling of methane in the presence of O2 and CO2 using mixtures with the molar ratio of CH4:O2:CO2=7.5:2:0, 7.5:1.5:0.5, 7.5:1:1 and 7.5:0.5:1.5 at 850°C was investigated. In the catalytic tests, 2Mn/SiO2, 2La/SiO2 and 5Na2WO4/SiO2 catalysts as well as mixed oxide 2Mn5Na2WO4/SiO2, 2La5Na2WO4/SiO2, 2La2Mn5Na2WO4/SiO2 catalysts were studied (where: the number in the description of catalyst represents a content in wt% of metal or Na2WO4). It has been found that replacement of O2 by CO2 leads to conversion of methane decrease, while in the same time the selectivity to C2 gradually raised. Over the 2La2Mn5Na2WO4/SiO2 the highest increase of selectivity to hydrocarbons C2 were observed.

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Nitrogen-rich natural gases as direct feedstocks in some prospective methane conversion processes : studies with CH4-N2 model mixtures

Czechowicz D., Skutil K., Taniewski M.

Polish Journal of Applied Chemistry

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2008

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nr 3-4/07,1-2/08

55-70

EN

The possibility to use nitrogen-rich natural gases directly, without separation and nitrogen removal, as feedstocks in some prospective novel CH4 conversion processes has been investigated. Various CH4-N2 mixtures containing up to about 90 vol.% of N2 were used as models for nitrogen-rich natural gases. The possible effect of N2 content in the feed on the course of methane oxidative coupling to ethylene and ethane over Na2O/CaO, methane and toluene oxidative cross-coupling to ethylbenzene and styrene over Na2O/CaO, oxygen-free methane dehydroaromatization to hydrogen, benzene and naphthalene over Mo/HZSM-5 and oxygen-free methane catalytic decomposition to hydrogen and carbon over NiCu/MgO, has been studied. Some detailed results and observed regularities have been reported and discussed. It was shown that in the irreversible processes of methane oxidative coupling and cross-coupling, no effect of CH4 dilution on the reactants conversion and on the yields and selectivities of the main products formation was observed under experimental conditions, at least up to about 80% of the nitrogen content. In the reversible processes of methane dehydroaromatization and methane catalytic decomposition, proceeding with the increase in the number of moles, it was observed the beneficial rise in the CH4 conversion and in the products yields with the growing dilution. Thus, it was shown that non-separated nitrogen-rich natural gases could be used as direct feedstocks in the investigated novel processes.

6

Detector tube for the determination of chlorine in air

Pitschmann V., Kobliha Z., Halámek E., Tušarová I.

Chemia Analityczna

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2005

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Vol. 50, No. 4

729-734

EN

Brief information is given on a method of determination of chlorine in air using a detector tube. The detector tube contains silica gel with immobilized reagents 4-aminoantipyrine and N-(l-naphtyl)ethylenediamine dihydrochloride which are stabilized by sodium sulfite and triethylene glycol. Chlorine concentration in the range 15 to 150 mg m-3 is evaluated on the basis of the length of the blue-violet coloration of the indicator layer.

PL

Opracowano metodę oznaczania chloru w powietrzu przy zastosowaniu rurki wskaźnikowej. Rurka wskaźnikowa zawiera żel krzemionkowy z unieruchomionymi na nim odczynnikami: 4-aminoantypiryną. dichlorowodorkiem N-(I-naftylo)etylenodiaminy, stabilizowanymi siarczynem sodowym iglikolemtrietylenowym. Stężenie chloru w zakresie 15-150 mg m-3 ocenia się na podstawie długości niebiesko-fioletowego zabarwienia warstwy wskaźnika.

7

The challenges and recent advances in C1 chemistry and technology

Taniewski M.

Polish Journal of Applied Chemistry

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2004

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Vol. 48, nr 1-2

1-21

EN

The challenges and recent advances in the main areas of C1 chemistry and technology were discussed. The growing role of methane as a source of energy, of transportable liquid fuels and of petrochemicals was demonstrated. The state-of-the-art, the latest progress in research and development (2000-2004) and the chances of oxidative coupling of methane, its aromatization, selective oxidation, reforming, Fischer-Tropsch synthesis, conversion of methanol to hydrocarbons, decomposition of methane, plasma and plasma-catalytic conversion of methane, were presented and considered. It was concluded that the role of catalysis and technology in the further development of C1-based processes would be crucial (novel catalysts, novel reaction pathways, novel processes).

PL

Przedyskutowano współczesne wyzwania i postępy w głównych obszarach chemii i technologii C1. Przedstawiono rosnącą rolę metanu jako źródła energii, ciekłych i łatwych do transportu paliw oraz petrochemikaliów. Omówiono stan wiedzy i ostatnie osiągnięcia w dziedzinie badań i rozwoju (2000-2004) a także przyszłościowe szanse utleniającego sprzęgania metanu, jego aromatyzacji, selektywnego utleniania, reformingu, syntezy Fischera-Tropscha, konwersji metanolu do węglowodorów, rozkładu metanu oraz plazmowej i plazmowo-katalitycznej konwersji metanu. Ukazano kluczową rolę katalizy i technologii w dalszym rozwoju procesów C1 (nowe katalizatory, nowe ścieżki reakcji, nowe procesy).

8

New spectrophotometric method for determination of cefpodoxime protexil

Srinivasa Rao Y., Chowdary K. P. R., Seshagiri Rao J. V. L. N.

Chemia Analityczna

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2004

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Vol. 49, No. 1

111-116

EN

A simple spectrophotometric method for the determination of pure cefpodoxime proxetil and in its pharmaceutical formulations has been developed. It utilises the pink colour formation following the complexation of cefpodoxime proxetil with sodium metaperiodate and brucine. The maximum absorbance of the complex appears at 520 nm and the system obeys Beerís law in the concentration range: 5-30 mg mL-1. The proposed method is selective, simple and inexpensive for the quantitative determination of cefpodoxime proxetil. It has been statistically validated.

PL

Opracowano prostą metodę spektrofotometrycznego oznaczania cefpodoksymu w stanie wolnym i w postaciach leku. Metoda wykorzystuje powstający różowy kompleks cefpodoksymu z metanadjodancm sodu i bmcyną. Ten chromogen, posiadający maksimum absorpcji przy df. fali 520 nm, spełnia prawo Beera w zakresie stężeń 5-30 ugmL(-1). Metoda została zwalidowana statystycznie. Zaproponowana metoda pozwala na selektywne, proste i ekonomiczne, ilościowe oznaczanie cefpodoksymu.

9

Hydrolysis and oxidation of 3[alfa],12[alfa]-diacetoxy-24,24-diphenyl-5ß-chol-23-ene and its derivatives

Mazurkiewicz W., Bartusik D.

Polish Journal of Applied Chemistry

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2003

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Vol. 47, nr 4

231-238

EN

The paper presents the syntheses of six compounds obtained from 3a,12a-diacetoxy-24,24-diphenyl-5b-chol-23-ene substrate. The substrate and products of its hydrolysis were oxidized to nordeoxycholic acid and oxo derivatives. In all cases the reaction yields were above 60%. All the compounds, particularly the derivatives of nordeoxycholic acid, are suitable starting materials for further syntheses of steroid derivatives and are potential fungicides or sorption promotors.

PL

W pracy przedstawiono drogę syntezy sześciu związków opartych na wyjściowym substracie 3a,12a-diacetoksy-24,24-difenylo-5b-chol-23-enie Produkty hydrolizy oraz substrat wyjściowy poddano utlenianiu dwiema metodami pozwalającymi na uzyskanie pochodnych kwasu nordeoksycholowego oraz pochodnych okso. We wszystkich przypadkach wydajność reakcji przekraczała 60%. Wszystkie te związki mogą być potraktowane jako wstęp do dalszych syntez pochodnych steroidowych, lub też mogą być przetestowane (przede wszystkim pochodne kwasu nordeoksycholowego) w badaniach farmakologicznych jako środki przeciwgrzybiczne lub promotory sorpcji.

10

Some properties of MgO and catalytic performance in oxidative coupling of methane

Taniewski M., Kuś S.

Polish Journal of Applied Chemistry

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2000

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Vol. 44, nr 4

181-194

EN

The catalytic performance of unpromoted MgO in oxidative coupling of methane to C(2)+ hydrocarbons (OCM) and a controversial question of possible MgO properties/performance relationship were studied. The properties and structure of several MgO samples of different origin (BET surface area and pore size distribution, surface morphology by electron scanning microscopy, phase characteristics by thermo-gravimetry, identification of impurities by AAS) were determined. Tests carried out in the small-scale laboratory unit with silica tubular reactor at 760°C, demonstrated the diversity of catalytic performance of applied MgO samples in OCM C(2) selectivity, in particular). It was shown that the surface area and the structure of MgO were not the main factors responsible for the diversity of catalytic performance. The content or absence of Ca compounds in applied MgO samples appeared to be the main factor. The presence of Ca compounds led to the increase in C(2) selectivity and activity of MgO. Similar effects were achieved by introduction of various alkalies, water, etc. to MgO. It was concluded that the variation in the basicity could be a decisive factor responsible for observed differences between MgO samples regarding their selectivity and activity in OCM.

11

Migration of lithium along the fixed bed of Li/MgO and its consequences to the catalytic performance in oxidative coupling of methane

Taniewski M., Lachowicz A.

Polish Journal of Chemical Technology

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1999

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Vol. 1, nr 1

36-39

EN

The migration of lithium along the bed of Li/MgO catalyst in oxidative coupling of methane has been investigated. A scaled-up stainless-steel tubular reactor with a fixed catalyst bed formed from two layers with different Li content was applied. It was discovered by AAS determination that the emission of volatile lithium compounds from the lithium rich working catalyst layer observed during its ageing, was followed with binding of emitted lithium by the poorer in lithium catalyst layer located below. Its consequences to the catalytic performance were studied. Under applied conditions, the main effect of the ageing of the catalyst was the decrease in C2 selectivity and the increase in COx selectivity, with only weak effect on methane conversion. It was found that the aged catalyst layer of low selectivity after its contact with the emission from the working fresh catalyst layer became more selective towards C2 formation. The phenomenon of migration of lithium should be taken into account in the efforts to prolong the period of effective work of the whole catalyst bed.