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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.
PL
Stwierdzono ilościowe wytrącanie szczawianów kobaltu(II) i manganu(II) (stężenia metali poniżej LOD: Co < 0,35 ppm, Mn < 0,27 ppm) w stężonym roztworze kwasu octowego (90% mas.), powszechnie stosowanym jako rozpuszczalnik w przemysłowych procesach utleniania p-ksylenu do kwasu tereftalowego. Obecność zanieczyszczeń typowych dla procesu utleniania p-ksylenu, czyli kwasu benzoesowego, kwasu bromowodorowego oraz jonów sodu nie miała negatywnego wpływu na powstawanie osadów. Obecność stałego kwasu tereftalowego w mieszaninie reakcyjnej miała pozytywny wpływ na proces odzyskiwania katalizatora. Zaobserwowano, że szczawiany tworzą aglomeraty na powierzchni stałego kwasu tereftalowego, co ułatwia oddzielenie osadu od cieczy macierzystej. Ponadto potwierdzono wysoką efektywność wytrącania w szerokim zakresie stężeń metali (50-1600 ppm). Wyniki pokazują, że strącanie kwasem szczawiowym jest skuteczną metodą odzyskiwania katalizatorów homogenicznych zawierających związki kobaltu(II) i manganu(II).
EN
A 1% soln. of (COOH)₂ in 90% MeCOOH was added to a 90% MeCOOH soln. contg. Co and Mn ions at concns. of 500 and 300 ppm, resp., and impurities typical of the oxidn. of p-xylene to C₆H₄(COOH)₂ (BzOH, HBr and Na ions) in amts. simulating the mother liquor compn. of a real industrial process. After mixing, the Co and Mn contents of the decanted liq. were detd. by AAS. Presence of impurities had no neg. impact on the ppt. formation. The presence of solid C₆H₄(COOH)₂ in the reaction mixt. had a pos. impact on the catalyst recovery process. Oxalates formed agglomerates on the surface of the solid C₆H₄(COOH)₂ which facilitated the sepn. of the ppt. from the mother liquor. The pptn. with (COOH)₂ is an efficient recovery method of spend Co(II) and Mn(II) homogeneous catalysts.
EN
The main product of the conversion of ethanol to acetone on a ZnO-CaO catalyst is acetone, the yield of which strongly depends on the composition of the reaction environment. When oxygen is present, the yield of products of destructive and complete oxidation increases greatly. In contrast, when water vapor is present, both the selectivity and conversion of ethanol increase. Therefore, the conversion of ethanol is the limiting step in the overall process, which determines the selectivity of the conversion of ethanol to acetone. In this regard, it appeared suitable to investigate the effect of introducing water to the contact zone. As experiments indicated, the addition of water caused a significant effect on the conversion, selectivity, and acetone yield on the ZnO-CaO catalyst. As the partial pressure of water vapor increases, the conversion of ethanol and the acetone yield increase, while the yield of carbon dioxide decreases. The decrease in carbon dioxide is associated not only with the inhibition of the conversion of ethanol to CO2. In this study, the adsorption of water vapor and ammonia on the surface of the ZnO-CaO catalyst was examined by infrared spectroscopy method. It has been shown that water vapor at low temperatures is adsorbed on the catalyst surface in the molecular form, while at higher temperatures it is adsorbed in the dissociative form. Co-transformation reactions of ethanol with acetic acid, acetaldehyde with ethylene, and acetaldehyde with acetic acid have been studied. The obtained results indicated that acetone is formed mainly through the stage of complexation of acetaldehyde with ethylene. The isomerization reaction of 1-butene to 2-butene has been investigated. It was found that the yield of cis-2-butene in the absence of water vapor is higher, likely attributed to the molecular adsorption of water on Lewis centers. Based on these findings, a scheme for the vapor-phase conversion of ethanol into acetone on the studied catalysts was formulated.
PL
Głównym produktem konwersji etanolu do acetonu na katalizatorze ZnO-CaO jest aceton, którego wydajność silnie zależy od składu środowiska reakcji. W obecności tlenu znacznie wzrasta wydajność produktów destrukcyjnego i całkowitego utlenienia. Natomiast w obecności pary wodnej wzrasta selektywność i konwersja etanolu. Dlatego konwersja etanolu jest etapem ograniczającym w całym procesie, który określa selektywność konwersji etanolu do acetonu. W związku z tym celowe wydawało się zbadanie wpływu domieszek wody do strefy kontaktu. Jak wykazały doświadczenia, dodatek wody miał istotny wpływ na konwersję, selektywność i wydajność acetonu na katalizatorze ZnO-CaO. Wraz ze wzrostem ciśnienia cząstkowego pary wodnej wzrasta konwersja etanolu i wydajność acetonu, podczas gdy wydajność dwutlenku węgla maleje. Spadek dwutlenku węgla jest związany nie tylko z hamowaniem konwersji etanolu do CO2. W niniejszej pracy metodą spektroskopii w podczerwieni badano adsorpcję pary wodnej i amoniaku na powierzchni katalizatora ZnO-CaO. Wykazano, że para wodna w niskich temperaturach jest adsorbowana na powierzchni katalizatora w postaci cząsteczkowej, natomiast w wyższych temperaturach jest adsorbowana w postaci dysocjacyjnej. Zbadano reakcje kotransformacji etanolu z kwasem octowym, aldehydu octowego z etylenem i aldehydu octowego z kwasem octowym. Uzyskane wyniki wykazały, że aceton powstaje głównie na etapie kompleksowania aldehydu octowego z etylenem. Zbadano reakcję izomeryzacji 1-butenu do 2-butenu. Stwierdzono, że wydajność cis-2-butenu w nieobecności pary wodnej jest większa, co prawdopodobnie wynika z molekularnej adsorpcji wody na centrach Lewisa. Na podstawie uzyskanych wyników zaproponowano schemat przemiany etanolu do acetonu w fazie gazowej na badanych katalizatorach.
EN
Azo dye is widely used in the textile industry since it is cost effective and simple to use. However, it becomes a continuous source of environmental pollution due to its carcinogenicity and toxicity. Various methods had been used to remove the azo dye in solution. One of the famous and frequently used is the Fenton process. The Fenton process is one of the advanced oxidation processes where iron catalysed hydrogen peroxide to generate hydroxyl radical. Treating azo dyes in solution requires a catalyst to enhance the process of degradation. Herein, high entropy alloys (HEAs) have been proposed as a catalytic material to enhance the performance of Fenton process for azo dye degradation. HEAs have been reported as a promising catalyst due to its high surface area. The higher the number of active sites, the higher the rate of azo dye degradation as more active sites are available for adsorption of azo dyes. The results have shown that HEAs can be used as a catalyst to fasten the Fenton reaction since the degradation time is proven to be shorter in the presence of HEAs. The method derived from the result of this study will contribute in treating azo dyes for wastewater management in the Fenton process.
5
Content available Katalizatory wykorzystywane w syntezie biodiesla
EN
Rising prices of electricity, conventional fuels and heating require decisive steps in the further development of technologies based on renewable energy sources. These include geothermal- ; hydrothermal- ; aerothermal- ; and solar energy. Due to the fact that the petrochemical industry is one of the fastest growing branches of the economy, we would like to expand on the topic related to biofuels. Biodiesel is an alternative fuel similar to conventional diesel. It is usually made from animal fat, vegetable oil and waste cooking oil. Its biodegradability, nontoxicity and lack of sulfur and aroma content make it superior to conventional gasoline and diesel. During fuel consumption, it emits fewer air pollutants and greenhouse gases other than nitrogen oxides. In this literature review, we will discuss the latest trends in the world related to catalysts used in biodiesel synthesis.
EN
This article presents a comparative analysis of the properties of two boiler catalyst carriers made of two types of natural aluminosilicates. Both materials have been share by external companies, and daily are used for commercial purposes. In preparing the material for research, it was crushed, and then a grain size of 0.315-0.63 mm has been selected and dried in a laboratory dryer at 110℃ for 12 hours. Then, the water absorption of materials has been determined. The research also presents their porous structure by using the mercury porosimetry method. The manuscript also contains the results of measuring the content of individual elements (K, Na, Mg, Ca, P, Fe, Al, Zn, Cu, Ni, Cr, Ti, Si) in catalyst carriers made by the method of atomic emission spectrometry with induction plasma excitation conjugated (ICP-AES).
PL
W niniejszym artykule przedstawiono analizę porównawczą właściwości wybranych nośników katalizatorów kotłowych wykonanych z dwóch rodzajów naturalnych glinokrzemianów. Oba materiały zostały udostępnione przez firmy zewnętrzne i na co dzień wykorzystywane są w celach komercyjnych. W procesie przygotowania materiału do badań dokonano jego rozdrobnienia, a następnie wyselekcjonowano ziarno o rozmiarze 0,315-0,63 mm, które to poddano suszeniu w suszarce laboratoryjnej w temperaturze 110℃ przez 12h. Kolejno wyznaczono chłonność wodną obu materiałów. W badaniach określono także ich strukturę porowatą przy pomocy metody porozymetrii rtęciowej. W manuskrypcie przedstawiono takżę rezultaty pomiaru zawartości poszczególnych pierwiastków (K, Na, Mg, Ca, P, Fe, Al., Zn, Cu, Ni, Cr, Ti, Si) w nośnikach katalizatorów wykonanego metodą emisyjnej spektrometrii atomowej ze wzbudzeniem w plazmie indukcyjnie sprzężonej (ICPAES).
EN
The article presents an innovative technology of fire prevention in goaves, based on injection of nitrogen and carbon dioxide inert gases mixture from treatment of exhaust gases from a methane combusting gas engine. The developed innovative technology and the constructed prototype of the installation producing inert gases are the final result of the research project entitled "Innovative and effective technology of inerting the goaf active or dammed longwall in an underground mining plant, extracting hard coal, using mixtures of inert gases obtained from the purification of exhaust gases from a gas engine and preventing the formation of endogenous fires", co-financed by the National Center for Research and Development (NCBR). The prototype installation was demonstrated in real conditions at the “Borynia” part of "Borynia-Zofiówka" mine, where, at the end of the research project, the prototype and the developed fire prevention technology with the use of gas engine exhaust gases were optimized and validated. Until now, under normal conditions in a hard coal mine, the fumes generated as a result of methane combustion in gas engines were emitted directly to the atmosphere. Innovative inerting technology, processing and reusing the exhaust gases produced by methane-fueled gas engines, in ecological context will contribute to the reduction of pollutant emissions in the mining sector, and, with mixing at the same time the carbon dioxide and nitrogen in the proper ratio in the mixture, it will fully utilize the advantages of each of these gases, as known when used in separate form. As a result, considering the possibility of generating a much higher amount of inert gases per time unit compared to the available technologies, and combining the physicochemical properties of nitrogen and carbon dioxide in one mixture, the innovative technological solution significantly increases the effectiveness of fire prevention, thus reducing the possibility of an endogenous fire.
8
Content available remote Optimization of the form of the catalyst intake system in the exhaust system
EN
The goal of the article was to optimize the geometric form of the converter intake system in order to improve the distribution of exhaust gas flow on the surface of the catalyst. The article describes the process of designing the converter inlet cone and the connection pipe, as well as optimizing their shape.
PL
Celem artykułu była optymalizacja kształtu geometrycznego układu dolotowego konwertera w celu poprawy rozkładu przepływu spalin na powierzchni katalizatora. Opisano proces konstrukcji stożka wlotowego konwertera i rury przyłączeniowej, a także optymalizację ich kształtu.
EN
The catalytic conversion of a model tar compound, namely: naphthalene contained in a simulated producer gas from wood gasification process was investigated. The sol-gel approach was used to create a mesoporous Cepromoted Ni/alumina catalyst with high surface area. A surface area of 333 m2g was achieved by calcination of the mesoporous catalyst (17 wt% Ni and 2.8 wt% Ce) under air conditions at 1123 K. The catalysts were characterized using the N2 adsorption-desorption, XRD, and SEM techniques, and their promotion effect on producer gas reforming and tar removal was studied under dry, steam, and partial oxidation conditions. The Ni-based catalysts effectively converted naphthalene and increased the proportion of H2 and CO in the reformed gas. Incorporating Ce into the catalyst increased the proportion of H2 and CO in the reformed gas, while lowering the amount of CH4 and CO2. In the absence of oxygen, catalytic reforming of the producer gas resulted in 79.6% naphthalene conversion, whereas catalytic partial oxidation conditions resulted in 99.1% naphthalene conversion.
EN
Combustion engines are the main driving force of passenger cars, trucks or buses. Engines burn fuels, and as a side effect, release many pollutions to the atmosphere. Car manufacturers had been aware of a need of lowering the amount of exhaust fumes. This brought on the market the first catalytic converters. Nowadays automobile catalyst manufacturing is the largest sector of demand of PGMs (mainly platinum, palladium and rhodium), and unfortunately consumption and future demand of there critical metals is getting higher. Over the past two decades, most countries around the world have developed and implement solutions that would minimize the impact of the growing number of cars on the environment. One solution contributing to this is the organisation of an end-of-life car collection and recycling network, which is now an integral part of automotive industry. The main drivers for the development of such network were stricter environmental regulations and economic conditions. The development of recycling is also becoming more popular in Poland. However, catalyst recycling system is still not transparent to all stakeholders. Due to the huge variety of catalysts and their different structure and composition of elements from the PGMs group, the valuation of their price before they are recycled is not obvious. This raises a lot of controversy and does not inspire trust among those who recycle their catalysts. The aim of this work is to show how the management of used catalytic converters looks like in Poland and how developed is network of catalysts recycling in Poland. At the same time this will show how important it is in terms of a circular economy and the recovery of valuable raw materials from a group of PGMs.
EN
This article presents an analysis of the validity of using catalytic additives for combustion with wood pellets in a low-power boiler. Five different catalytic additives have been used in the research, the chemical composition of which based on TiO2, MnO2, aqueous H2PtCl6 solution and 99.5% pure aqueous urea solution. The carrier for the active substance has been sodium aluminosilicate. The catalytic additive has been applied until the appropriate concentration in the pellet structure has been obtained, corresponding to 0.1% in relation to the weight of the fuel burned. Based on the results of the measurements, the percentage reduction of pollutant emissions into the atmosphere (CO, NOx, SO2 and particulate matter) and fuel consumption resulting from the use of individual active substances have been determined. The manuscript also showed the effect of the savings in fuel consumption and the unit cost of the catalytic additive on the amount of annual avoided costs for heating and domestic hot water preparation.
PL
W niniejszym artykule przedstawiano analizę zasadności zastosowania dodatków katalitycznych do spalania z pelletem drzewnym w kotle małej mocy. W badaniach zastosowano pięć różnych dodatków katalitycznych, których skład chemiczny bazował na TiO 2 , MnO 2 , wodnym roztworze H 2 PtCl 6 i 99.5% czystym wodnym roztworze mocznika. Za nośnik dla substancji aktywnej posłużył glinokrzemian sodu. Dodatek katalityczny nakładany był do momentu uzyskania odpowiedniego stężenia w strukturze pelletu, odpowiadającego 0.1% w stosunku do masy spalanego paliwa. W oparciu o wyniki przeprowadzonych pomiarów określono procentową redukcję emisji zanieczyszczeń do atmosfery (CO, NO x , SO 2 i pyłu zawieszonego) oraz zużycia paliwa wynikającego ze stosowania poszczególnych substancji aktywnych. W manuskrypcie wykazano także wpływ wielkości oszczędności w zużyciu paliwa i kosztu jednostkowego dodatku katalitycznego na wysokość rocznych kosztów unikniętych dla ogrzewania i przygotowaniu ciepłej wody użytkowej.
EN
To make clear the feasibility and influence factors of diesel fuel autothermal reforming to hydrogen, PdCeCr-FeCu/Al2O3 catalyst was prepared by equivalent-volume impregnation method. Experimental facility based on an adiabatic tubular reactor with preheating section was designed and set up, the behaviors of diesel reforming to hydrogen with straight-run diesel as a raw material according to the analysis of the components were studied. Diesel oil reforming over a catalyst for hydrogen production was analyzed using an adiabatic tubular reactor with a preheating section that was designed and built in-house. The operating conditions were optimized. Under the suitable operating conditions, viz., catalyst bed inlet temperature of 700°C, diesel liquid space velocity of 0.24 h–1, water-carbon ratio of 20, and oxygen-carbon ratio of 0.6, the hydrogen yield reached 28.3 (mol/mol).
EN
The necessity of development of technical solutions that will allow to reduce carbon monoxide emissions of flue gases of industrial productions is substantiated. It is shown that the most rational design solution to the problem of carbon monoxide pollution during the firing of electrode blanks is the use of aerated concrete blocks with a catalyst, which can be quickly and conveniently located directly on the carbon material of the “green” electrodes pouring in the subfloor space of the firing furnaces. Modified by oxides of Mn4+, Fe2+, Fe3+, Cu2+, Cr3+ -catalysts based on aerated concrete were obtained. It is shown that in an empty reactor in the temperature range 200–400 °С the degree of conversion of carbon monoxide in the absence of a catalyst is zero. It is established that on the investigated catalysts based on aerated concrete 100% oxidation of carbon monoxide is achieved at a temperature of 390 °C in the case of using a mixture of catalyst powders 30% CuO + 70% MnO2, 40% CuO + 60% MnO2, 50% Fe (FexCr1-x) 2O4 + 50% MnO2; 50% Fe3O4 + 50 % MnO2. It is determined that the addition of ferrite catalyst powder in aerated concrete in a mixture or without manganese dioxide does not critically affect the mechanical properties of the products.
EN
The processes of manganese (II) ions removal from water using sorbent catalysts and ion exchange materials modified with iron oxides were studied. It was shown that manganese ions oxidize very slowly in artesian water, even when the pH is adjusted to 9.0. Intensive aeration of solutions due to stirring also does not promote the oxidation of manganese (II) ions. The degree of manganese extraction due to oxidation is reduced from 20–30% for solutions with a concentration of manganese ions of 1 and 5 mg/dm3 to 11–15% for solutions with a concentration of 15 and 30 mg/dm3. A significant increase in the oxidation efficiency of manganese ions was achieved by using magnetite as a sorbent catalyst. The efficiency of water demanganization increases along with the intensity of water aeration when mixing solutions. It was established that strongly acid cation exchangers provide efficient extraction of manganese ions from water. At the same time, a high exchange capacity of strong acid cation exchange resin KU-2–8 in acid and salt form was noted. It was shown that the capacity of manganese ions of this cation exchange resin in the Ca2+-form is slightly lower. When using the KU-2–8 in Ca2+-form of cation exchange resin to remove manganese ions from the solution already in the first samples, the leakage of manganese ions at the level of 10 mg/dm3 and above was observed. This indicates that this form of ion exchanger is not suitable for deep purification of water from manganese (II) ions. In order to increase the efficiency of manganese ion extraction from water, increase the duration of the filter cycle, magnetite and magnetite-modified KU-2–8 cation exchange resin were used as a sorbent-catalyst. It was shown that the cation exchange resin modified with magnetite provides the removal of a significant part of manganese ions due to catalytic oxidation on magnetite. The conditions of effective manganese extraction under static and dynamic conditions are determined.
EN
In this work, the process of water deironing by using magnetite as a catalyst to accelerate the oxidation of iron ions in an aqueous medium was investigated. It was shown that the efficiency of iron ion extraction depends on the solution concentration, sorbent dose and contact time. In all cases, the use of magnetite accelerated the process of extraction of iron by more than an order of magnitude in comparison with similar experiments on the oxidation of iron without the addition of a catalyst. At the pH values greater than 6, the use of magnetite as a catalyst contributes to the deep purification of water from iron ions.
EN
The catalysts based on natural zeolite-clinoptilolite of Sokyrnytsia deposit modified with oxides of Mn4+, Fe2+, Fe3+, Cu2+, Cr3+ were synthesized. It was determined that 100% conversion of carbon monoxide was achieved at a temperature of 390°C when using the copper-manganese-oxide catalyst (30% CuO + 70% MnO2). It was shown that although the use of the manganese-oxide catalyst provided 92.8% of CO conversion degree, this catalyst had the most advantages for application compared to the other studied solids. The structural parameters of the manganese-oxide catalyst were determined using XRD, SEM, and nitrogen adsorption. The composition of the main elements of the catalyst samples was determined by micro-X-ray spectral analysis. It was shown that using the catalyst containers in chambers heated by flue gases in the fire channels of a multi-chamber furnace for baking of electrode blanks can be one of the constructive solutions to the problem of flue gas purification from carbon monoxide. The environmental safety of the copper-manganese-oxide catalyst application for the treatment of the flue gases of electrode production is justified by obtaining a catalyst from spent sorbents for purification of the manganese-containing natural water and its non-toxicity in the case of burial or storage in landfills.
EN
In this study, pyrolysis of shredded waste tire was carried out thermally and catalytically in a fixed bed reactor. Thermal pyrolysis was performed at temperatures of 330 °C, 430 °C, 530 °C, and 630 °C under Ar. flow rate of 0.5 L/min as a carrier gas and retention time of 15 min catalytic pyrolysis was carried out at temperature of 530 °C. The effects of temperature and two types of catalysts (CaCO3 and SiO2/Al2O3) were studied on the yield of pyrolysis products. Fourier transform infrared spectroscopy (FTIR) and Gas chromatography mass spectrometry (GC-MS) analysis for the oil products that were obtained by thermal and catalytic pyrolysis at 530 °C for chemical characterization. Oil, solid, and gas products yield by thermal pyrolysis at 530 °C were 50 wt. %, 35.6 wt. %, and 14.4 wt. % respectively, when the CaCO3 catalyst was used, the products distribution was 52 wt. %, 38.5 wt. %, and 9.5 wt. % respectively. While using SiO2 /Al2O3 the pyro oil, and char, and gas were decreased to 47 wt. %, 38 wt. %, and 15 wt. % respectively. The chemical composition of pyrolysis oil mainly included hydrocarbons compounds, predominantly Limonene which was represented by Cyclohexene, 1-methyl-4-(1-methylethenyl).
18
Content available remote Metody otrzymywania nadkwasów karboksylowych
PL
Dokonano przeglądu prac naukowych związanych z wytwarzaniem nadkwasów organicznych przez katalityczne utlenianie kwasów organicznych nadtlenkiem wodoru.
EN
A review, with 29 refs., of catalysts used and conditions for oxidn. of org. acids with H₂O₂ to resp. peracids.
EN
A green procedure for the one-pot three-component synthesis of 1-amidoalkyl-2-naphthol and 3-amino-1-phenyl-1H benzo[f]chromene-2-carbonitrile derivatives from the reaction of 2-naphtol, aldehydes, and malononitrile/acetamide in the presence of a catalytic amount of Fe3O4@enamine-B(OSO3H)2 as an efficient and novel heterogeneous magnetic nanostructure catalyst is described. The catalyst was characterized using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), vibrating sample magnetometry (VSM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). These strategies possess some merits such as simple work-up method, easy preparation of the catalyst, short reaction times, good-to-high yields, and non-use of hazardous solvents during all steps of the reactions. Moreover, due to the magnetic nature of the catalyst, it was readily recovered by magnetic decantation and can be recycled at least six runs with no considerable decrease in catalytic activity.
EN
Activated carbon was oxidised with concentrated nitric acid and impregnated with urea to form nitrogen-containing groups. Such a support was impregnated with cobalt, copper or silver nitrates to obtain catalysts for the selective catalytic reduction of nitrogen oxides with ammonia. Infrared spectra confirmed the formation of carboxylic and other organic oxygen-containing groups during oxidation. Nitrogen-containing species resulted from urea thermal decomposition. The metal-containing samples were hydrophilic. Cobalt and copper were present in the samples as small Co3O4 and CuO crystallites, while silver occurred in the form of large metallic crystallites, as seen from the X-ray diffraction patterns. Low temperature N2 sorption revealed that all samples were microporous solids, and the chemical and thermal treatment did not change their textural properties. The copper admixture caused the highest NO conversion, but worsened the selectivity and thermal stability of functionalised carbon support.
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