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1

Prekatalizatory oligomeryzacji olefin oparte na kationach chromu(III) oraz kobaltu(II) : właściwości fizykochemiczne oraz katalityczne

Malinowski Jacek, Drzeżdżon Joanna, Sikorski Artur, Jacewicz Dagmara Elżbieta

Wiadomości Chemiczne

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2022

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[Z] 76, 11-12

943--962

EN

The introduction describes the most important facts about the development of polyolefins. This is followed by a description of the role of polyolefins and the most important applications in industry and everyday life. The paper presents new, highly active precatalysts for oligomerization of olefins. These are coordination compounds based on chromium(III) cation, anions of various polycarboxylic acids and auxiliary ligands, such as 1,10-phenanthroline or 2,2'-bipyridyl. This review presents their crystallographic structures and basic parameters describing the elementary cell. The catalytic properties of the obtained oligomerization products using chromium(III) coordination compounds by MALDI-TOF MS are described. In conclusion, the presented precatalysts are compared with others described in the literature.

2

Wpływ dodatku palladu do perowskitu LaFeO3 na aktywność katalityczną w utlenianiu węglowodorów

Kucharczyk B., Szczygieł B., Winiarski J., Kokot vel Kokocińska P.

Przemysł Chemiczny

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2018

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T. 97, nr 10

1684--1688

PL

Perowskity La1-xPdxFeO3 (x = 0-0,25) wytworzono przez wysokotemperaturową kalcynację (750°C) mieszaniny azotanów lantanu, żelaza i palladu. Przedstawiono charakterystykę katalizatorów zawierających różne ilości Pd (powierzchnia właściwa BET, XRD, SEM). Otrzymane perowskity zastosowano jako warstwę aktywną katalizatorów monolitycznych do utleniania metanu i n-heksanu. Częściowe zastąpienie La w perowskicie przez Pd zwiększało aktywność katalizatora w procesie utleniania obydwu węglowodorów. W utlenianiu metanu i heksanu wzrost aktywności katalizatora z perowskitem LaFeO3 następował przy zastąpieniu 0,15 mola i 0,1 mola La przez Pd. Aktywność perowskitu La1-xPdxFeO3 rosła ze wzrostem zawartości Pd.

EN

La, Fe and Pd nitrates were mixed together in various proportions and calcinated at 750°C to obtain La1-xPdxFeO3 (x = 0-0.25) perovskites supported on a steel substrate and then used as an active catalyst layer for oxidn. of MeH and hexane. A partial replacement of La with Pd in the perovskite resulted in an increase in their catalytic activity. The activity increased with increasing Pd content in perovskite.

3

Struktura produktów pirolizy kwasów huminowych węgla brunatnego i katalityczne właściwości utlenionych karbonizatów

Czechowski F., Klimkiewicz R.

Górnictwo Odkrywkowe

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2018

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R. 59, nr 1

27--38

PL

Kwasy huminowe wydzielone z węgla brunatnego z kopalni Konin zostały scharakteryzowane w zakresie analizy technicznej i elementarnej oraz FTIR, 13C NMR jak też termograwimetrycznej i różnicowej analizy termicznej. Zostały one poddane procesowi konwencjonalnej pirolizy. Skład molekularny gazowych oraz lotnych ciekłych produktów pirolizy kwasów huminowych określono odpowiednio przy pomocy GC oraz GC-MS. Uwolnione składniki gazowe są reprezentowane przez ditlenek węgla, tlenek węgla, metan oraz wodór. Lotne produkty ciekłe stanowią mieszaninę struktur polialkilobenzenowych oraz pochodnych fenolu i metoksyfenoli, w tym głównie gwajakolu. Związki łańcuchowe są reprezentowane przez serię homologiczną kwasów tłuszczowych wykazujących dużą przewagę homologów parzystowęglowych w zakresie C22-C32 oraz serię homologiczną węglowodorów alifatycznych w postaci par n-alk-1-enów/n-alkanów w zakresie homologów C8-C36. Otrzymane wyniki wskazują na materię roślin naczyniowych wzbogaconych w biopolimer występujący w roślinnych kutykulach jako składnik przyczyniający się do budowy substancji humusowej kwasów huminowych. Ze wzrostem temperatury pirolizy następuje pogłębianie defunkcjonalizacji karbonizatu. Utlenione karbonizaty przez częściowe zgazowanie tlenem powietrza wykazują specyficzną aktywność w kierunku dehydratacji i dehydrogenacji w teście z udziałem alkoholu n-butylowego. Karbonizaty kwasów huminowych są obiecującym materiałem dla otrzymywania katalizatorów do niedestruktywnej transformacji oksygenatów.

EN

Humic acids extracted from Konin brown coal (Midland, Poland) were characterized by proximate and elemental analyses as well as FTIR, 13C NMR and thermogravimetric and differential thermal analyses. They were subjected to conventional pyrolysis. Molecular composition of gaseous and liquid pyrolysis products released during the process were determined by GC and GC-MS, respectively. Released gaseous products are composed of carbon dioxide, carbon monoxide, methane and hydrogen. The liquid volatile products constitute mixture of polyalkyl substituted benzene compounds as well as phenolic and methoxyphenolic mainly of guaiacol type derivatives. Chained compounds are represented by homological series of fatty acids with pronounced prevalence of even carbon numbered representatives in the C22-C32 range and aliphatic hydrocarbons represented by n-alk-1-enes/n-alkanes pairs in the range C8-C36. Obtained results indicate on vascular plant matter enriched in biopolymers encountered in plant cuticles as the constituent contributing to humic substance of humic acids. Pyrolysis leads to gradual defunctionalization of remaining solid carbonizates upon increasing heat treatment. Oxidized humic acids carbonizates with air oxygen revealed specific catalytic dehydration and dehydrogenation activity in n-butyl alcohol test. They are promising materials for obtaining catalysts for nondestructive transformations of oxygenates.

4

Propylene oxide polymerization in the presence of layered double hydroxides

Dan O., Butenko E., Kapustin A.

Chemistry-Didactics-Ecology-Metrology

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2018

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R. 23, NR 1-2

137--142

EN

Propylene oxide polymerization in the presence of layered double hydroxides with different concentration of basic sites on their surface has been studied. It is shown that the polymerization can be catalyzed by both basic and acidic sites. On the basis of kinetic experiments the mechanisms of reaction undergoing were proposed.

PL

W artykule badano polimeryzację tlenku propylenu w obecności warstwowych wodorotlenków podwójnych o różnej ilości centrów zasadowych na powierzchni. Wykazano, że kataliza polimeryzacji zachodzi zarówno w centrach zasadowych, jak i kwasowych. Na podstawie doświadczeń kinetycznych zaproponowano mechanizmy reakcji.

5

Electrocatalytical Properties of Palladium-Decorated Cobalt Coatings Obtained by Electrodeposition and Galvanic Displacment

Skibińska K., Kutyła D., Kołczyk K., Kwiecińska A., Kowalik R., Żabiński P.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 3

1517--1521

EN

This work presents the studies on the electrochemical process of thin palladium layers formation onto electrodeposited cobalt coatings. The suggested methodology consists of the preparation of thick and smooth cobalt substrate via galvanostatic electrodeposition. Cobalt coatings were prepared under different cathodic current density conditions from acidic bath containing cobalt sulphate and addition of boric acid. Obtained cobalt layers were analyzed by x-ray diffraction to determine their phase composition. Freshly prepared cobalt coatings were modificated by the galvanic displacement method in PdCl2 solution, to obtain smooth and compact Pd layer. The comparison of electrocatalytic properties of Co coatings with Co/Pd ones enabled to determine the influence of Palladium presence in cathodic deposits on the hydrogen evolution process.

6

Synthesis and activity evaluation of Ce-Mn-Cu mixed oxide catalyst for selective oxidation of co in automobile engine exhaust: effect of Ce/Mn loading content on catalytic activity

Bilal Yasir, Nasir Muhammad Ali, Nasreen Sadia, Akhter Niaz Ahmed, Pasha Riffat Asim, Noor Muhammad Farhan

Advances in Science and Technology. Research Journal

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2018

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Vol. 12, no 1

260--266

EN

A series of Mn-doped CeO2-CuO catalyst (CeO2-MnOx-CuO) (Ce/Mn molar ratio of 0.5, 1.0 2.0 and 3.0) were prepared using co-precipitation method for the selective oxidation of CO in automobile engine exhaust. The content of copper was 5.0 wt. % in each sample. Catalysts were installed on the automobile engine exhaust and CO amount was recorded with help of CO sensor, with and without the catalyst. The catalytic converter efficiency was estimated for each catalyst through efficiency formula. It was observed that Ce/Mn catalyst with a molar ratio of 2.0 shows the maximum efficiency (88.35%). Stability of conversion process was analyzed by plotting the CO amount with respect to time. The catalyst with Ce/Mn molar ratio of 2.0 performed the most streamline conversion process with least deviations.

7

Fabrication of Ag and Au nanoparticles in cross-linked polymer microgels for their comparative catalytic study

Shah L. A., Sayed M., Siddiq M.

Materials Science Poland

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2017

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Vol. 35, No. 3

651--659

EN

Three dimensional cross-linked polymer microgels with temperature responsive N-isopropyl acrylamide (NIPAM) and pH sensitive methacrylic acid (MAA) were successfully synthesized by free radical emulsion polymerization with different amounts of MAA. Silver and gold nanoparticles with the size of 6.5 nm and 3.5 nm (±0.5 nm), respectively were homogeneously reduced inside these materials by chemical reduction method at pH 2.78 and 8.36 for the preparation of hybrid materials. The samples were characterized by FT-IR, DLS and TEM techniques. The catalytic activity of the hybrid materials was investigated for the reduction of 4-nitrophenol (4-NP) using NaBH4 as reducing agent by UV-Vis spectroscopy. The hybrid polymer network synthesized at pH 8.36 showed enhanced catalytic efficiency compared to the catalysts synthesized at pH 2.78. In this study, it has been stated that the catalyst activity strongly depends on the amount of MAA, pH value during synthesis and the type of entrapped metal nanoparticles.

8

Katalityczne oczyszczanie spalin z kotłów małej mocy

Świątek Ł., Kułażyński M.

Przemysł Chemiczny

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2016

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T. 95, nr 8

1630--1633

PL

Przeprowadzono badania rozkładu temperatury na powierzchni deflektora w retortowym kotle małej mocy zasilanym peletem drzewnym. Spreparowano katalizatory wanadowe osadzone bezpośrednio na podłożu deflektora oraz na krzemionkowej warstwie pośredniej o zawartości wanadu 20,1 g/m² deflektora. Ponadto spreparowano katalizator platynowy o warstwie pośredniej z Al₂O₃ o zawartości platyny 0,08 g/m² deflektora. Oznaczono stężenia CO oraz NOx w spalinach emitowanych z kotła podczas rozruchu oraz pracy z mocą nominalną. Efektem działania katalizatorów było zmniejszenie zawartości NOx do ok. 8%.

EN

Temp. distribution on the surface of the deflector in a retort small power boiler supplied with wood pellet was studied. Two V₂O₅ catalysts were deposited directly on the deflector surface or intermediately on SiO₂ carrier and one Pt catalyst was deposited on an intermediate Al₂O₃ layer. The exhaust gases were studied for CO and NOx contents. Use of the catalysts resulted in redn. of NOx with CO or hydrocarbons present. The deflector-supported V₂O₅ catalyst was the most efficient.

9

Mössbauer study of a tetrakis (pentafl uorophenyl) porphyrin iron (III) chloride in comparison with the fluorine unsubstituted analogue

Kaczmarzyk T., Dziedzic-Kocurek K., Rutkowska I., Dziliński K.

Nukleonika

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2015

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Vol. 60, No. 1

57--61

EN

Mössbauer investigations, in association with density functional theory (DFT) calculations, have been conducted for the molecular and electronic structures of iron (III) [tetrakis (pentafl uorophenyl)] porphyrin chloride [(F20TPP)Fe:Cl], as a Fe(III)-tetraphenylporphyrin complex containing chloride axial ligand and substituted hydrogen atoms by fl uorine ones in the four phenyl rings, in comparison with its fl uorine unsubstituted analogue [(TPP)Fe:Cl]. It was found that the parameters of Mössbauer spectra of both complexes are close to one another, and correspond to the high-spin state of Fe(III) ions, but they show the different temperature dependence and the quadrupole doublets in Mössbauer spectra show different asymmetry at low temperatures. Results of DFT calculations are analyzed in the light of catalytic activity of the halogenated complex.

10

Aktywność katalityczna mieszanych tlenków metali La-Mn (La-Co) o strukturze perowskitu w spalaniu rozcieńczonego metanu

Miniajluk N., Trawczyński J., Zawadzki M., Chomiak M.

Przemysł Chemiczny

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2014

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T. 93, nr 6

873-877

PL

Badano aktywność katalityczną mieszanych tlenków La-Mn i La-Co o strukturze typu perowskitu w spalaniu rozcieńczonego metanu. Stwierdzono, że materiały nieosadzone charakteryzowały się wysoką aktywnością katalityczną, podczas gdy odpowiadające im próbki osadzone na La-Al22O3 wykazywały mniejszą aktywność w tym procesie. Materiały La-Mn wykazywały lepiej rozwiniętą powierzchnię właściwą oraz większą aktywność katalityczną niż materiały La-Co. Największą aktywność wykazywały materiały, w których część lantanu zastąpiono strontem. Określono korelację pomiędzy aktywnością katalityczną badanych materiałów a udziałem tlenu sieciowanego na ich powierzchni.

EN

Six perovskite type oxides (both bulk and supported) were synthesized by the citrate-assisted sol-gel method and examd. by X-ray diffraction anal., N adsorption at low temp., X-ray photoelectron spectroscopy and temp.-programmed redn. with H2, and then used as catalyst in dild. Methane combustion. All oxides showed surface area 7.3-79.3 m2/g and were catalytically active. The chem. compn. of the prepd. oxides and their oxidn. state showed the presence of the lattice, adsorbed and hydroxyl or carbonate oxygens. A correlation between the CH4 conversion at 520°C on the studied oxides and share of lattice oxygen on the surface was found.

11

Use of MgO to Promote the Oxyethylation Reaction of Lauryl Alcohol

Pilarska A., Lukosek M., Siwińska-Stefańska K., Pilarski K., Jesionowski T.

Polish Journal of Chemical Technology

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2014

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Vol. 16, nr 2

36--42

EN

Synthesis of magnesium hydroxide was performed by the precipitation method with the use of magnesium sulfate and sodium hydroxide. The infiuence of temperature and ratio of reagents was studied. Magnesium hydroxides, and the magnesium oxides obtained from them by thermal decomposition, were analyzed to determine their bulk density, polydispersity and particle size. The magnesium oxide with the largest surface area was tested as a catalyst in the oxyethylation of lauryl alcohol, and shown to be selective but poorly reactive in comparison with commercially available catalysts. Further studies are needed to improve its reactivity.

12

Catalytic oxidation of carbon monoxide on lithium-zinc ferrites with a spinel structure

Tatarchuk T.

Ekologia i Technika

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2014

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R. 22, nr 2

70--75

EN

The catalytic activity of Li-Zn ferrites with the chemical composition ZnyLi0,5-0,5yFe2,5-0,5yO4 (0.0 < y < 1.0) towards oxidation of CO has been investigated. The structures of the catalysts were characterized by X-ray diffraction, surface area, catalytic and saturation magnetization measurements. X-ray diffraction data shows that Li-Zn ferrite powders with a spinel structure have been formed successfully in all the samples. Saturation magnetization increases with the increase of zinc concentration up to y=0.4 and then it decreases with the increase of the zinc content. The catalytic oxidation of carbon monoxide was carried out at 673, 773, and 873 K using a flow system. The results obtained revealed that the activity of the catalysts are strongly affected by the structure of the ferrite spinel formed as a result of the solid-solid interaction between Fe2O3, ZnO and Li2O. Correlations between the composition, magnetic and catalytic properties of the catalysts are reported. The mechanism of interaction of CO with adsorbed oxygen was studied using antistructural model.

PL

Zbadano aktywność katalityczną ferrytów Li-Zn o składzie chemicznym ZnyLi0,5-0,5yFe2,5-0,5yO4 w utlenianiu monotlenku węgla. Katalizatory zostały scharakteryzowane przy pomocy dyfraktometrii rentgenowskiej, wartości powierzchni właściwej, aktywność katalityczną oraz pomiary saturacji magnetycznej . Dane XRD wykazały, że Li-Zn ferryty posiadające strukturę spinelową zostały uzyskane we wszystkich próbkach. Saturacja magnetyczna wzrasta wraz ze wzrostem zawartości cynku do y=0.4 a zatem maleje. Oksydację katalityczną monotlenku węgla przeprowadzono w temperaturach 673, 773 oraz 873 K w układzie przepływowym. Wyniki uzyskane wskazują, że aktywność katalizatorów w dużym stopniu zależy od struktury spinelowej, powstającej na skutek reakcji pomiędzy Fe2O3, ZnO oraz Li2O. Zbadano zależność aktywności katalitycznej od składu chemicznego katalizatorów. Mechanizm oddziaływania CO z adsorbowanym tlenem zbadano za pomocą modelu antystruktury.

13

Synthesis, characterization and catalytic properties of SAPO-11 molecular sieve synthesized in hydrothermal media using di-isopropylamine as template

Chellappa T., Costa M. J. F., Nascimento W. A., Ferreira De Lima L., Bassan I. A., Tavares M., Fernandes V. J., Menezes A., Guilherme Meira L., Telesforo Nóbrega De Medeiros J., Maribondo Do Nascimento R.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2014

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Vol. 62, nr 3

481--488

EN

A microporous SAPO-11 Molecular sieve was successfully synthesized by the hydrothermal method, using a single agent, as an organic template: di-isopropylamine (DIPA). The obtained solid was calcined at 550◦C for three hours, after which the flow of nitrogen was exchanged for that of synthetic air and submitted for another ten hours of calcination, so as to remove the single agent: di-isopropylamine, which after the removal of the template could be observed by the high crystallization of the sample. Furthermore, the molecular sieve was characterized by XRD, SEM, TG-DTG and N2 adsorption desorption (BET analysis). The obtained catalyst proved to have a high potential catalytic activity and selectivity, through the obtained characterization results, exhibiting good hydrothermal stability. The catalytic performance of SAPO-11 was tested by the deactivation/regenerability of the coked sample, furthered by cracking of n-hexane reaction and high olefins selectivity was obtained.

14

Synthesis, Characterization and Catalytic Activity of Resin-based Diiron(III) Interphase Catalysts: Model for Methane Monooxygenase

Shan C., Qian G. R., Zhang L., Luo Y. L.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 1

163-168

EN

Three resin-based m-oxo diiron(III) interface catalysts have been successfully prepared to model the functional properties of methane monooxygenase (MMO). The catalysts were characterized and exhibited the catalytic activities in the oxidation of alkanes to responding alcohols and ketones in acetonitrile at room temperature by 30% hydroperoxide (H2O2) or tert-butyl hydroperoxide (TBHP) as the oxidants. For 2,6-di-tert-butylphenol as the substrate, the C-C coupling was found in the two reaction systems. The reaction mechanisms were proposed with the predominant radical mechanism.

15

Synthesis of claw-like CuO and its catalytic activity in the thermal decomposition of ammonium perchlorate

Wang J., He S., Li Z., Jing X., Zhang M.

Materials Science Poland

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2009

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Vol. 27, No. 2

501--507

EN

Claw-like CuO was prepared by solution process at 100 °C simply by using copper nitrate and hexamethylenetetramine for 3 h. The structure and morphology of resulting CuO powders were characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. CuO nanocrystals were studied as an additive for promoting the thermal decomposition of ammonium perchlorate. With the addition of the claw-like CuO nanocrystals, thermal decomposition temperature of ammonium perchlorate decreased. CuO nanocrystals showed catalytic activity on the decomposition of ammonium perchlorate.

16

Effect of N,N'-Dimethylthiourea on the Electroreduction of In(III) Ions in Aqueous Perchlorate Solutions at the Mercury Drop Electrodes

Nosal-Wiercińska A., Dalmata G.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 7

1473-1473

EN

N,N'-Dimethylthiourea catalyzes electroreduction of In(III) ions on a mercury drop electrodes in an aqueous perchlorate solution in the range 0.5 < pH < 2. The catalytic activity in creases with the in crease of concentration of N,N'-dimethylthiourea. Electroreduction of In(III) ions in the presence of N,N'-dimethylthiourea is a multi-step reaction. The transfer of electrons is preceded by the hy drolysis of In(H2O)6 3+ ions and formation of In–N,N'-dimethylthiourea complexes. These complexes are formed on the electrode surface, because of the significant lo cal N,N'-dimethylthiourea concentration resulting from its adsorption on mercury. The active complexes participate in consecutive transfer of electrons.

17

Modification of TiO2 with W(VI) Ions: Photocatalytic Activity and Some Other Properties of Materials

Kobasa I. M., Wlodarczyk R. P.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 10

1785-1805

EN

New TiO2 based materials doped with W(VI) compounds have been synthesized.We recorded diffusion reflection and absorption spectra and determined phase composition of thematerials. It has been found that thematerials containing 0.01–5.0mass%of the dope exist in the crystalline form of anatase while 10 mass%of the dope leads to the rutile crystalline form.We determined parameters of both types of lattice and proposed explanation for difference in parameters of doped and not doped lattices. Dependence of photocatalytic activity (PA), catalytic activity (CA), electroconductivity sigma, and magnetic susceptibility chi of a sample on the dope content are similar and all of them have maximum at 0.01 mass % of the dope. It has been found that PA and CA linearly depend on sigma and chi . Character of such dependencies has also been explained. Our experimental results proved that the higher is PA of a sample, the higher CA it reveals. This correlation can be observed along the range of existence of anatase crystalline modification as long as formation of rutile lattice changes the basic factors governing PA and CA.

18

Synthesis, Characterization and Catalytic Activity of Salen-type Schiff Base Polychelates

Bansod A., Aswar A.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 10

1615-1622

EN

Polymeric complexes of Mn(II), Fe(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) with Schiff base derived from 4,4-bis-[(salicylaldehyde-5)azo]biphenyl and 1,3-diaminopropane have been synthesized and characterized by microanalysis, IR, and electronic spectra and magnetic moment data. All these complexes are dark coloured and insoluble in water and most of the common organic solvents. Thermogravimetric analysis indicated the presence of coordinated water in complexes. The solid-state conductivity of the ligand and its polychelates was studied in the temperature range 313–413 K and chelates were found to show semiconducting behaviour. The Mn(II), Fe(II), Co(II) and Ni(II) polychelates have also been assessed for the catalytic epoxidation of styrene.

19

Bioreaktory membranowe : aspekty wpływające na wybór rozwiązania

Trusek-Hołownia A., Noworyta A.

Inżynieria i Aparatura Chemiczna

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2005

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Nr 4s

109-110

EN

Basic factors characterizing technological-processing properties of membrane bioreactors with a passive and active role of membrane are presented. A quantitative analysis of these factors enables the rational choice of a kind of membrane bioreactor for a given application.

20

Synthesis and Catalytic Activity of Square-Planar Ni(II) Complexes of Bis-N,N'-disubstituted Oxamides and Related Ligands for Epoxidation of Olefins

Zheng G., Wang Q., Yan S.

Polish Journal of Chemistry

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2004

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Vol. 78 / nr 1

19-25

EN

Four new monomeric square-planar nickel(II) complexes of two bis-N,N'-disubstitute oxamides and related ligands have been prepared and characterized, namely [NMe4]2[Ni(L)]_xH2O, where L = dbopba = 3,5-dibromo-o-phenylenebis-(oxamate) and dbmeopba = 3,5-dibromo-o-phenylenebis-(N_-methyloxamidate), L = meopba = 4-methyl-o-phenylenebis-(oxamate) and memeopba = 4-methyl-o-phenylenebis-(N_- methyloxamidate).NMe4 is thetetramethylammonium cation. Based on elemental analyses, IR and UV spectroscopies and molar conductance data, the complexes are proposed to have a square-planar structure. Their catalytic activities for aerob