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2
Content available remote Chemia gazu syntezowego i ditlenku węgla : zarys współczesnych możliwości
PL
Przedstawiono rolę oraz znaczenie chemii tlenków węgla w rozwoju przemysłu syntezy chemicznej.
EN
The role and importance of C oxides in the development of chem. synthesis industry was presented.
PL
Omówiono rozwój i cechy współczesnej chemii, a także jej poznawczą i cywilizacyjną misję. Zwrócono uwagę, że po erze rolniczej, przemysłowej i naukowo-technicznej, świat wkracza w Wiek Środowiska (a także informatyki), w którym cywilizacja podąży drogami opartymi nie tylko na potrzebie opanowywania przyrody, ale także umiejętności harmonijnego z nią współżycia. Będzie to okres realizacji tzw. proekologicznej strategii zrównoważonego trwałego rozwoju (sustainable development), w którym wprowadzane będą zrównoważone technologie podporządkowane pokonywaniu barier rozwojowych (materiałowej, surowcowej, ekologicznej). W odniesieniu do chemii identyfikowana jest dodatkowo bariera psychologiczna - objawy niechęci społecznej i strachu przed chemią. Wspomniano o działaniach branży chemicznej na rzecz samodoskonalenia poprzez inicjowanie i realizację wielu prośrodowiskowych programów. Omówiono pojęcie "interdyscyplinarna chemia" oraz rolę chemii w rozwiązywaniu globalnych problemów świata. Konstatując, że chemia w istocie współkształtuje przyszłość, Autor wyraża opinię, że w interesie ludzkości jest rozkwit i słoneczna przyszłość chemii.
EN
This paper presents the development and features of contemporary chemistry, its cognitive and civilisation mission. It was noted that after the eras of agriculture, industry, science and technology, the world entered the "Age of Environment" (also informatics), where civilisation is to follow not only the roads of harnessing the nature, but also those of harmonious coexistence with it. This age, therefore, should be a period of implementing the strategy of sustainable development, when sustainable technologies, aimed at overcoming growth barriers (material, energy and environmental barriers), will be introduced. In the case of chemistry, one more barrier has been identified: a psychological barrier - manifested by social aversion to and fear of chemistry. Mention is made of "self-improvement" activities of the chemical sector consisting in initiating and carrying out a number of environmental programmes. The concept of "interdisciplinary chemistry" is discussed along with the role of chemistry in solving global problems of the world. Concluding that chemistry does, in fact, shape the future, the author expresses the opinion that the growth and sunny future of chemistry is in the interest of humankind.
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.
EN
Some opinions and discussions are presented concerning the following subjects: 1) the concept of sustainable development, interpretations and current status, 2) sustainable technologies, sustainable chemical technologies and their environmental aspects, 3) sustainable technologies in petrochemical industry and their general development trends, 4) recent advances in sustainable petrochemical technologies; some examples
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).
11
Content available remote Chemia i technologia C1 : badania w Polsce i w świecie
13
Content available remote Alternatywne technologie petrochemiczne
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.
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.
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