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1

Szkielety metalo-organiczne do zastosowań w zakresie ochrony środowiska

Baluk Mateusz Adam, Trzebiatowska Patrycja Jutrzenka, Pieczyńska Aleksandra

Wiadomości Chemiczne

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2024

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[Z] 78, 3-4

189--217

EN

Current challenges related to climate change, environmental degradation, and the increasing energy demand impose an urgent need for society to seek innovative solutions in environmental protection. In response to these issues, scientists have been developing areas related to novel functional nanomaterials for years. Among these materials, particular attention is drawn to metal-organic frameworks (MOFs), a new type of porous coordination polymers built from metal centers and organic ligands. The exceptional properties of MOFs come from their porous structure exhibiting high surface area, low density, large pore volume, also recyclability and the ability to regulate pore size and activity by selecting appropriate building blocks. MOFs can be synthesized by various routes and the most popular methods are the following: solvo-(hydro)thermal, mechanochemical, electrochemical, sonochemical or microwave-assisted synthesis. The type of synthesis influences the MOFs properties such as crystal size, specific surface area or possibility of scalable. Furthermore, MOFs activity in sorption or catalysis can be enhanced by postsynthetic modification (PSM), which enables the introduction of new functional groups or particles on/into MOF. Thanks to these properties and tunability, MOFs are finding increasingly broad applications in various processes that can serve different functions such as catalysts, photocatalysts, or sorbents. Due to the possibility of control of pore structure, their adsorption properties, and the nature of active sites, lately, MOFs and MOF-based materials have been investigated in gas adsorption and separation, hydrogen storage, CO2 capture, chemical sensing, electrochemical water splitting, biomass conversion, polymerization and drug delivery. This article will provide general information about the structure and key properties of MOFs, as well as methods of their synthesis and possibilities for modification. However, the focus will primarily be on indicating the various applications of MOFs in environmental applications (Figure 1). The use of MOFs in processes for removing organic and inorganic pollutants from water, air purification, gas separation, pollutant detection, and fuel generation and storage will be discussed. Additionally, the potential uses of MOFs as catalysts in transesterification processes, CO2 fixation, depolymerization, or biomass conversion will be highlighted.

2

Projektowanie efektywnego katalizatora reakcji uwodornienia acetylenu do etylenu poprzez dobór prekursora i nośnika

Plis Anna, Kleszcz Mateusz, Samardakiewicz Bartłomiej, Rutkowski Rafał, Połczyński Piotr, Lewera Adam, Jurczakowski Rafał

Przemysł Chemiczny

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2023

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T. 102, nr 11

1169--1176

PL

Przedstawiono wyniki badań selektywnego uwodornienia acetylenu w obecności katalizatorów zawierających pallad jako fazę aktywną. Jako nośniki zastosowano porowate matryce Al₂O₃ oraz mieszaniny Al₂O₃ i zeolitu Beta. W pracy zbadano także wpływ prekursora palladu, czyli kompleksów chlorkowych i azotanowych(III) palladu(II) na właściwości katalityczne otrzymanych materiałów. Badania katalityczne przeprowadzono w skali laboratoryjnej w reaktorze odzwierciedlającym proces przemysłowy. Najwyższą aktywność i selektywność katalizatora uzyskano w obecności katalizatora otrzymanego w wyniku adsorpcji kompleksów azotanowych(III) palladu(II) na nośniku Al₂O₃.

EN

Pd catalysts were obtained by impregnating chloride or nitrate(III) complexes of Pd(II) on Al₂O₃ or zeolite Beta or Al₂O₃ and zeolite Beta mixt. as supports. In a laboratory installation simulating an industrial process, catalytic tests were carried out in the reaction of selective hydrogenation of acetylene at a concn. of 4% vol. in ethylene. The highest activity and selectivity were achieved in the presence of a catalyst obtained by adsorption of Pd nitrate(III) complexes on an Al₂O₃ support.

3

Alkoholiza mocznika jako potencjalna metoda otrzymywania węglanu propylenu na skalę techniczną

Kotyrba Łukasz, Siewniak Agnieszka, Woszczyński Piotr, Nowakowska-Bogdana Ewa, Chrobok Anna

Przemysł Chemiczny

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2022

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T. 101, nr 12

1112--1117.

PL

Przeprowadzono test katalizatorów w procesie syntezy węglanu propylenu metodą alkoholizy mocznika. Spośród katalizatorów cynkowych, cynowych, glinokrzemianowych i MgO największe wydajności reakcji uzyskano, stosując zasadowy węglan cynku (78,9%) i tlenek cynku (76,9%). Badania wykazały, że tlenek cynku nie traci swoich właściwości katalitycznych po kolejnych nawrotach, jednak jego straty po każdym cyklu reakcyjnym wynosiły 27,4 - 33,1%. Dowiedziono, że rozpuszczony w mieszaninie poreakcyjnej cynk może być z niej usunięty za pomocą wymieniaczy jonowych, takich jak ziemia bieląca TONSIL 570 FF lub kationit Purolite CT151.

EN

Propylene glycol, urea and catalyst (compds. of Zn, Mg, Sn or aluminosilicates) were mixed in the flow of N₂, at 150°C, for 4 h. The compn. of the reaction mixt. was detd. by means of GC with an internal standard. The Zn content of the liq. samples was quantified by X-ray fluorescence. The highest yields of propylene carbonate were obtained in the presence of basic ZnCO₃ (78.9%) and ZnO (76.9%). ZnO losses after each reaction cycle amounted to 27.4-33.1%. The Zn dissolved in the reaction mixt. was removed with the aid of ion exchangers.

4

Synteza i zastosowanie styrylopochodnych arenów, karbazolu i ferrocenu w projektowaniu e-stereoregularnych krzemoorganicznych materiałów hybrydowych

Majchrzak Mariusz

Wiadomości Chemiczne

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2021

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[Z] 75, 1-2

137--162

EN

The potential for expanding the variety of catalytic methods for carbon-carbon bond formation is being currently explored in many research centres all over the world. An increasing use of selected d-block metals as catalysts in the synthesis has brought new methods of functionalization of organic and organometallic compounds of great importance for development of polymer chemistry and organic chemical technology [5, 6]. This work describes very precise and controlled catalytic transformations as useful tools for the synthesis of new E-conjugated organic, organosilicon molecular and polymeric compounds. The combination of Suzuki-Miyaura coupling and silylative coupling reactions as a simple and efficient method is established for designing new E-stereoregular hybrid materials in the presence of well-defined transition metal (TM) catalysts. All presented compounds can be interesting precursors for a further functionalization that may significantly increase the possibility of their application in the design and synthesis of new functional materials.

5

CO2 zamiast CO : katalityczna konwersja CO2 w syntezie związków karbonylowych

Wójcik Ewelina, Trzeciak Anna M.

Wiadomości Chemiczne

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2021

|

[Z] 75, 3-4

395--422

EN

Modem industrial carbonylation processes, leading to functionalized carbonyl compounds, are based on the application of highly toxic and flammable carbon monoxide. Recently, carbon dioxide which is non-toxic and abundant, has attracted attention as a perfect C1 source to build new C-C and C-N bonds. From the standpoint of green and sustainable chemistry, it is appealing and challenging to combine the reduction of CO2 with subsequent carbonylation using in situ formed CO. Herein we present the application of CO2 as C1 building block for the carbonylation of different organic compounds in the presence of transition metal catalysts (e.g. Pd, Rh, Ru, Fe). Industrially important organic compounds has been obtained in hydroformylation, dehydrogenation, hydrogenation, aminocarbonylation and carboxylation reactions with CO2. On the other hand, rapid reduction of CO2 to CO could processed in the metal catalyst - free systems, using a catalytic amount of fluoride salt and stoichiometric amount of di- or hydrosilane. In these reactions silyl formate has been identified as an important intermediate formed from silane and carbon dioxide. Also hydrazine and sodium borohydrate have been used for CO2 reduction to formic acid or other products. Obviously, these reactions could be restricted because of their sensitivity to the applied conditions, high cost of reactants as well as the waste generated. The presented examples of catalytic carbonylation reactions with CO2 as a source of CO group illustrate a high technological potential of this strategy.

6

Characteristics of the structure of natural zeolites and their potential application in catalysis and adsorption processes

Sobuś Natalia, Czekaj Izabela, Diichuk Volodymyr, Kobasa Igor M.

Technical Transactions

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2020

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Vol. 117, iss. 1

art. no. e2020043

EN

Authors present a short review of selected natural-origin zeolite materials. This article discusses the structure, classification and ability to modify natural zeolites, along with examples of their potential applications as adsorbents or catalysts.

PL

Autorzy przedstawili krótki przegląd wybranych materiałów zeolitowych pochodzenia naturalnego. W artykule omówiono strukturę, klasyfikację i możliwości modyfikacji naturalnych zeolitów, wraz z przykładami ich potencjalnych zastosowań jako adsorbentów lub katalizatorów.

7

Katalizatory palladowe immobilizowane w materiałach typu MOF aktywne w reakcjach uwodornienia

Augustyniak Adam W., Trzeciak Anna M.

Wiadomości Chemiczne

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2019

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[Z] 73, 3-4

221--241

EN

Palladium immobilized in metal-organic frameworks (MOF) exhibit promising catalytic properties in hydrogenation of different unsaturated substrates. Due to the specific porous and crystalline structure MOFs can contribute in bonding and activation of organic substrates, increasing catalytic efficiency of Pd@MOF composites. The superior tunability of MOFs structures enables to design highly selective catalysts for hydrogenation of different substrates, such as olefins, esters, ketones, alcohols or alkynes. Due to the synergistic effects of palladium and MOF not only high activity but also high selectivity can be achieved. The article presents representative examples of MOF-based palladium catalysts for hydrogenation to illustrate perspectives, also technological, of their application.

8

A study of ruthenium-based catalysts used in homogeneous transfer hydrogenation of acetophenone

Mikołajczyk Filip, Kamiński Kamil

Chemical and Process Engineering

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2019

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Vol. 40, nr 2

213–-222

EN

A detailed comparison of catalytic properties of two different ruthenium-based catalysts in the reaction of homogeneous hydrogenation of acetophenone was performed. Additionally, methods of synthesis of both catalysts were tested and optimized in order to achieve the best possible quality and purity of the final catalysts. NMR analysis was used to analyze and identify the composition of ruthenium compounds and gas chromatography was used to analyze the conversion rate of hydrogenation reactions. It was determined that RuCl2(PPh3)3 obtained with a modified method described by Shaw’s group (Shawet al., 2007) had the best catalytic properties in the reaction performed under conditions described in Liang Wang’s publication (Wang et al., 2014). It was also determined that for concentration ratio of substrate to RuCl2(PPh3)3 amounting to 250:1 the conversion rate was much higher than that of the reaction performed with a double dose of the catalyst. Results of experiments also show that samples of the post-reaction solution should be analyzed right after the reaction, because even if they are stored in low temperature the amount of product can change up to 3–5% compared to the base sample and this change is not predictable. These findings have significant implications for further research of the reaction of homogeneous transfer hydrogenation of ketones. With the right catalysts and methods of their synthesis other parameters of this reaction can be optimized. The most important one is a change of solvent from isopropyl alcohol to a less toxic substance like water. This may increase the value of the reaction in green chemistry and chemical industry.

9

Decomposition of hydrogen perodixe - kinetics and review of chosen catalysts

Pędziwiatr P., Mikołajczyk F., Zawadzki D., Mikołajczyk K., Bedka A.

Acta Innovations

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2018

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no. 26

45--52

EN

Hydrogen peroxide is a chemical used in oxidation reactions, treatment of various inorganic and organic pollutants, bleaching processes in pulp, paper and textile industries and for various disinfection applications. It is a monopropellant, which, when purified, is self-decomposing at high temperatures or when a catalyst is present. Decomposing to yield only oxygen and water(disproportionation), hydrogen peroxide is one of the cleanest, most versatile chemicals available. The catalytic decomposition of hydrogen peroxide allows the use of various catalysts that will increase the rate of decomposition. Comparison and description of the most commonly used catalysts were presented in this review.

10

Biomasa - źródło cennych związków organicznych

Retajczyk J., Wróblewska A.

Wiadomości Chemiczne

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2017

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[Z] 71, 3-4

241--262

EN

So far, much attention was paid to processes which allow to obtain biofuels from biomass and less important was receiving from biomass valuable chemical compounds. Biomass is a source of a variety of compounds, such as: hydrocarbons, triglycerides, glycerol, hydroksymetylofurfural, cellulose, hemicellulose and pentoses, lignin and lignocellulose. Taking into account the application of the mentioned above compounds, a large number of articles describing catalytic conversion of biomass to valuable chemical compounds has been written during last 10 years. The articles presented specific types of reactions for compounds contained in biomass, such as: hydrolysis, hydrogenation or isomerization, which allow to obtain valuable products. The reactions are catalyzed among others by: metals deposited on the activated carbon, metal oxides, alloys and zeolites. Researchers still improve processes, adapting them to the structure of highly functionalized particles contained in biomass and process needs. At the same time, scientist focused on cost reduction. Renewable raw materials are converted to the intermediates in physical, chemical and physicochemical processes. Next, obtained intermediates are used for receiving valuable chemicals, such as: lubricants, solvents and products that were previously obtained from petroleum. This work presents the conversion of biomass to compounds which have been already prepared by conventional synthetic methods. Besides chemical pure compounds, catalytic reactions with using metals, lead to obtain mixtures of compounds which can be used for the large volume production: additives for paper, paints, resins, foams, surfactants, lubricants and plasticizers. In the chemical industry for many years it has been placed emphasis on processes that are environmentally friendly. Scientists have also focused on improving the activity of used catalysts and the selectivity of products.

11

Możliwości katalitycznego zastosowania materiałów odpadowych

Książek S., Kida M., Koszelnik P.

Czasopismo Inżynierii Lądowej, Środowiska i Architektury / Journal of Civil Engineering, Environment and Architecture

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2017

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z. 64, nr 2/II

55--62

PL

Zrównoważona chemia stanowi jedną z form działań zmierzających do zmniejszenia zanieczyszczeń środowiska i jest ważnym elementem zrównoważonego rozwoju. Zielona chemia dostarcza rozwiązań do takich globalnych wyzwań jak zmiana klimatu, zrównoważone rolnictwo, energia, zatrucie środowiska i wyczerpywanie bogactw naturalnych. Zielone technologie nie tylko chronią środowisko naturalne, ale zazwyczaj są również korzystne z punktu widzenia ekonomicznego. Podstawowym problemem dla środowiska jest znaczne zmniejszenie się zapasu surowców naturalnych. Zatem, dążenie do większej rozmaitości źródeł surowcowych to ważny obszar działania zielonej chemii. Kataliza należy do podstawowych narzędzi realizowania wszystkich zasad zielonej, zrównoważonej chemii wychodząc od badań podstawowych do zastosowań przemysłowych. Według zasad zielonej chemii, gdzie tylko jest to możliwe, powinno dążyć się do stosowania surowców odnawialnych oraz odpadów, które nie tylko zapewniają alternatywne surowce odnawialne, ale także stanowią materiał do produkcji katalizatorów. Zastosowanie materiału naturalnego jako katalizatora lub substratu do wytwarzania katalizatora powoduje nie tylko obniżenie kosztów związanych z produkcją katalizatorów, ale sprawia, że stosowany proces jest przyjazny dla środowiska. Ponadto, wykorzystanie materiałów odpadowych zmniejsza problem unieszkodliwiania odpadów. Wśród najbardziej obfitych zasobów produktów ubocznych technologii są przede wszystkim odpady z rolnictwa, górnictwa i produkcji metali, a w szczególności przemysłu hutniczego. Celem pracy jest scharakteryzowanie właściwości katalitycznych wybranych materiałów odpadowych.

EN

Sustainable chemistry is one of the forms of action to reduce pollution of the environment and it is an important element of sustainable development. Green chemistry provides solutions to such global challenges as climate change, sustainable agriculture, energy, toxics in the environment and the depletion of natural resources. Green technology will not only protect the environment, but they are usually also preferable from the economic point of view. The main concern for the environment is a significant reduction in the supply of natural materials. Therefore, the pursuit of a greater variety of sources of natural materials is an important area of activity of green chemistry. Catalysis is one of the basic tools of implementation of all principles of green, sustainable chemistry, from basic research to industrial applications. According to the seventh principle of green chemistry, where possible, should seek to use renewable raw materials and waste, which not only provide alternative renewable raw materials, but also provide the material for the production of catalysts. The use of natural material or waste material as catalyst or a substrate for the preparation of the catalyst will not only reduce the costs associated with the production of catalysts, but makes the used process is environmentally friendly. Waste materials also are valuable materials for the production of catalysts or are themselves active catalysts. In addition, the use of waste materials reduces the problem of waste disposal. Among the most abundant resources of technology products are primarily agricultural, mining and metals, and in particular the steel industry. The aim of the work is to characterize the catalytic properties of selected waste materials.

12

Improving the environmental performance of the internal combustion engine by the use of in-cylinder catalyst

Andrych-Zalewska M.

Combustion Engines

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2017

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R. 56, nr 1

129--132

EN

The problems of using the inner surfaces of a combustion chamber as catalytic converters in order to reduce the harmful exhaust emissions were discussed in this paper. The proper choice of the catalyst is one of the most important issues. The interaction between the burned mixture and the catalyst is not limited by the kinetics of the chemical reactions but depends primarily on the flow rate of the reactants to the catalyst surface during combustion. The lifespan of a catalytic layer is determined by the application technique, where plasma spraying is the most popular and most accessible method. However, when it comes to the catalytic coating durability, it is not an efficient option, as ion implantation is indicated shows greater potential in this respect. In this research the coating of aluminum titanium and chromium-nickel have been applied to the engine head and the piston crown. Then the modified catalytic parts were used in a CI combustion engine and the obtained emission results were compared with the reference results. Another set of tests was performed for an SI engine, powered with gasoline and methane, where the piston crown was covered with a thermal layer of zirconium oxide and a catalytic layer of platinum. The beneficial effects of these in-cylinder catalysts on exhaust emissions and the possible problems in the wide spread use of such solutions have been presented.

13

Zastosowanie związków renu w katalizie

Malarz J., Leszczyńska-Sejda K., Benke G., Ciszewski M.

Rudy i Metale Nieżelazne Recykling

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2016

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R. 61, nr 10

429--434

PL

W artykule przedstawiono przykłady katalizatorów renowych stosowanych w reakcjach epoksydacji, metatezy olefin oraz innych reakcjach pozwalających na utworzenie nowych wiązań węgiel-węgiel, węgiel-heteroatom (C-N, C-O, C-S), a także w reakcjach utleniania czy redukcji. Stosowane w tych reakcjach związki renu to nie tylko proste katalizatory organiczne (np. MTO), ale również złożone związki kompleksowe zawierające rozbudowane ligandy, a także heterogeniczne katalizatory osadzone na stałych nośnikach. Najbardziej znanym katalizatorem renowym jest MTO (metylotrioksoren(VII), CH3ReO3), który wykazuje aktywność w reakcjach metatezy olefin i epoksydacji, ale również w reakcjach utleniania alkoholi oraz eterów. Z punktu widzenia katalizy heterogenicznej, ważnym katalizatorem jest tlenek renu(VII) osadzony na stałym nośniku (np. Al2O3, SiO2 czy Al2O3-SiO2). Tego typu katalizatory stosowane są przede wszystkim w reakcjach metatezy olefin. Ponadto bimetaliczne katalizatory renowo- platynowe osadzone na stałych nośnikach, są stosowane w procesie reformingu surowej benzyny.

EN

Rhenium catalysts are widely applied in various chemical reactions in an industrial scale. Owing to produced catalysts complex organic compounds, which synthesis is impossible or impeded by other methods, maybe obtained. This work exemplifies application of rhenium catalysts in epoxidation and metathesis reactions of olefins as well as other react/on types al¬lowing formation of new carbon-carbon and carbon-heteroatom (C-N, C-0, C-S! bonds and also in oxidation and reduction reactions. Rhenium compounds used in these reactions are not only simple organic catalysts such as MTO but complex compounds containing well-developed //-gands and heterogeneous catalysts embedded on solid matrices too. MTO (methyltrioxorheniumlVlll CH3ReO}) is probably the most known rhenium catalyst that is active in olefins metathesis and epoxidation reactions and in alcohols and ethers oxidation reactions too. Based on heterogeneous catalysis rhenium(VII) oxide deposited on a solid matrix e.g. Alfl^ 5i02 or Alfl3-5i02 is an important catalyst's type that is mainly used in metathesis reactions. In addition bimetallic rhenium-platinum catalysts deposited on solid matrices are used in raw gasoline reforming.

14

Mezoporowate materiały węglowe jako obiecujące katalizatory utleniającego odwodornienia alkanów

Jarczewski S., Kuśtrowski P.

Chemik

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2016

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Vol. 70, nr 6

298--309

PL

Atrakcyjne właściwości, do których zaliczyć można rozwiniętą powierzchnię właściwą, uporządkowany układ szerokich kanałów wewnątrz ziarnowych oraz obecność względnie dużej liczby powierzchniowych grup tlenowych, sprawiają, że mezoporowate materiały węglowe cieszą się ogromnym zainteresowaniem licznych grup badawczych związanych z chemią materiałów oraz katalizą. W pracy przedstawiono krótki przegląd dotyczący możliwości użycia materiałów węglowych o kontrolowanej mezostrukturze jako katalizatorów reakcji utleniającego odwodornienia alkanów.

EN

Peculiar properties, such as a high specific surface area, an ordered arrangement of wide intraparticle pores as well as a relatively high concentration of surface oxygen-containing functional groups, make mesoporous carbons interesting materials for various research groups working in the field of materials chemistry and catalysis. In this work, a short review concerning the possibility of application of carbon materials with controlled mesostructure as catalysts for the oxidative dehydrogenation of alkanes is presented.

15

A Mechanistic Model of a Passive Autocatalytic Hydrogen Recombiner

Rożeń A.

Chemical and Process Engineering

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2015

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Vol. 36, nr 1

3--19

EN

A passive autocatalytic hydrogen recombiner (PAR) is a self-starting device, without operator action or external power input, installed in nuclear power plants to remove hydrogen from the containment building of a nuclear reactor. A new mechanistic model of PAR has been presented and validated by experimental data and results of Computational Fluid Dynamics (CFD) simulations. The model allows to quickly and accurately predict gas temperature and composition, catalyst temperature and hydrogen recombination rate. It is assumed in the model that an exothermic recombination reaction of hydrogen and oxygen proceeds at the catalyst surface only, while processes of heat and mass transport occur by assisted natural and forced convection in non-isothermal and laminar gas flow conditions in vertical channels between catalyst plates. The model accounts for heat radiation from a hot catalyst surface and has no adjustable parameters. It can be combined with an equation of chimney draft and become a useful engineering tool for selection and optimisation of catalytic recombiner geometry.

16

W pogoni za sadzą

Kopacz A.

Wiadomości Chemiczne

|

2014

|

[Z] 68, 9-10

919--939

EN

Soot is produced simultaneously by the incomplete combustion of fossil fuels. Investigations of soot elemination methods are currently focused on light fuel oil boilers. The overview of various transition metal properties points at iron as the most promising cation. The technology of existing oil burners excludes modifications necessary to install additional catalytic conversters. The most feasible way to eliminate soot is to introduce the catalyst in the form of fuel additive. Iron iron oxides and/or hydroxides are suggested as base for production of fuel-borne-catalyst.

17

Polimery z odciskiem molekularnym jako biomimetyki metaloenzymów

Czulak J., Trochimczuk A., Marcinkowska A.

Wiadomości Chemiczne

|

2014

|

[Z] 68, 9-10

783--809

EN

This paper presents methods of the synthesis and applications of biomimetic catalytic systems produced from molecularly imprinted polymers (MIP). MIPs contain cavities, which are complementary to the imprinted template, thus possess high selectivity and affinity for the molecules resembling template. MIPs have various applications such as: sorption, chromatography, solid phase extraction, drugs transport and catalysis. However, this article is a review of catalytic systems containing in their active sides one of the selected metal ions: copper(II), cobalt(II), zinc(II), iron(III) or nickel(II). Presented catalytic systems are used in hydrolysis, oxidations, hydrogenations and aldol condensation reactions. This review deals with papers published till 2013.

18

Termokatalityczna konwersja związków smołowych w gazie ze zgazowania węgla

Babiński P., Łabojko G., Krztoń A., Łamacz A.

Karbo

|

2014

|

Nr 4

228--236

PL

Scharakteryzowano rodzaje smół otrzymywanych w różnych typach zgazowania węgla. Omówiono główne metody usuwania składników smołowych z gazów procesowych. Przetestowano katalizator niklowy w formie wytłoczek i pastylek osadzony na tlenku ceru i cyrkonu w skali laboratoryjnej oraz wielkolaboratoryjnej. Testy katalityczne reakcji reformingu parowego toluenu i 1-metylonaftalenu katalizatorów kondycjonowanych w gazie rzeczywistym ze zgazowania węgla wykazały że ich aktywność jest zachowana, badania termograwimetryczne pokazały niewielką ilość depozytów węglowych ulegających spaleniu w temperaturze do 350°C. Badania wykazały, że optymalna temperatura dla rozkładu związków smołowych wynosi 800°C, a stosunek nadmiaru pary wodnej H2O/C powinien wynosić 2,4. Eksperymenty w skali wielkolaboratoryjnej potwierdziły skuteczność termokatalitycznego usuwania związków smołowych z modelowego gazu syntezowego w temperaturze 900°C przy czasie przebywania wynoszącym 3s. Obecność katalizatora podnosi również wydajność H2 i CO będących pożądanymi składnikami gazu syntezowego.

EN

Types of tars obtained in different types of coal gasification were characterized. Main removal methods of tar compounds in process gas were discussed. Nickel catalyst in the form of pellets and pills supported on zinc and cerium oxides was tested in lab and big lab scale. Tests of toluene and 1-methylnaphtalene steam reforming with catalysts conditioned in real gas from coal gasification showed that its activity is preserved, thermogravimetric studies indicated only small amount of carbon deposits undergoing combustion up to 350°C. Studies showed that optimal temperature for decomposition of tar compounds is 800°C, a ratio of steam excess should be 2.4. Big laboratory scale experiments confirmed effectiveness of thermo catalytic removal of tar compounds from model synthesis gas at 900 °C and residence time of 3 s. Presence of catalyst increases yield of H2 and CO which are desirable compounds of synthesis gas.

19

Xylose substrate as the only nutrient in the operation of microbial fuel cells

Vajda B., Nemestothy N., Bakonyi P., Bélafi-Bakó K.

Environment Protection Engineering

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2014

|

Vol. 40, nr 2

131--141

EN

Microbial fuel cells are bioelectrochemical devices converting chemical energy of organic compounds (i.e. biomass) into electrical energy by catalytic reactions of microbes under anaerobic conditions. The operation of two-chamber microbial fuel cells by Shewanella putrefaciens and mesophilic anaerobic sludge was studied comparatively, using xylose and glucose as solo substrates during the experiments. It was found that higher electric power was generated by the multicultural system than by the monoculture.

20

Oktakarboksyftalocyjaniny – związki o interesujących właściwościach spektralnych, fotochemicznych i katalitycznych

Nackiewicz J., Suchan J., Kliber M.

Chemik

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2014

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Vol. 68, nr 4

369--376

PL

Przedstawiono metody syntezy oktakarboksyftalocyjanin, MPcOC. Omówiono ich widma absorpcyjne UV-Vis, asocjację oraz wybrane właściwości fotochemiczne i katalityczne. Opisano wpływ czwartorzędowych soli amoniowych na widma UV-Vis i asocjację CuPcOC, fluorescencję roztworów wodnych ZnPcOC oraz aktywność katalityczną CoPcOC w homogenicznym aerobowym utlenianiu L-cysteiny.

EN

The article presents synthesis methods of octacarboxyphthalocyanines, MPcOC. Their UV-Vis absorption spectra, their association and selected photochemical and catalytic properties are also discussed. Moreover, the article describes the impact of quaternary ammonium salts on UV-Vis spectra and CuPcOC association, fluorescence of aqueous solutions of ZnPcOC and catalytic activity of CoPcOC in homogeneous aerobic oxidation of L-cysteine.