Obiettivo
The objective of this work has been the development of a highly selective and temperature tolerant catalyst for the synthesis of dimethyl ether (DME). The key steps in DME synthesis are methanol synthesis, partial methanol dehydration and the water gas shift reaction. This combination results in a synergistic effect which relieves the unfavourable thermodynamics which apply to methanol synthesis. Almost full conversion of synthesis gas to DME is achieved in a single pass at moderate pressures. However, the reaction is strongly exothermic and large amounts of heat have to be removed.
The relationships between the catalytic properties of HZSM-5 type zeolites and their degree of dealumination have been investigated. An optimum range of acidity and site density has been identified leading to the preparation of zeolites with a higher temperature tolerance while still preserving sufficient activity to make them suitable as dehydration catalysts. The most promising zeolites were mixed with standard methanol catalysts and were tested. Byproduct selectivity is highly dependent on the way in which the 2 catalysts are mixed.
Long terms catalyst stability has been demonstrated and a 450-hour pilot plant test has been conducted.
Dimethyl ether (DME) and water, rather than methanol, can be reacted with carbon monoxide using a rhodium catalyst to produce acetic acid, which can be derivatised to yield methyl acetate and acetic anhydride. The DME itself can be synthesised directly from synthesis gas much more efficiently, and at lower pressures, than can methanol.
The advantages of using this process are:
the separate synthesis of methanol at high pressure can be avoided;
synthesis gas recycling, which is necessary in the methanol synthesis reactor, is avoided;
separate synthesis of carbon monoxide is avoided since it can be provided by selecting reaction conditions and synthesis gas composition so as to leave over sufficient carbon monoxide in the effluent from the dimethyl ether reactor.
Calculations have shown that this process is much more economical than the conventional methanol carbonylation route.
An improved process has been developed for the conversion of methanol, or preferably dimethyl ether (DME), into liquid hydrocarbons for use as high octane motor fuel.
DME is preferred as feedstock since:
less water is generated and so the catalyst lifetime is increased;
approximately 20% of the heat of reaction can be released before entering the adiabatic reactor, thereby reducing the exit temperature.
One of the achievements of the research programme has been the generation of a comprehensive set of data linking the zeolite catalyst's degree and rate of dealumination to process parameters such as temperature, steam partial pressure and time. The ultimate catalyst lifetime can be extended by applying steam modified zeolites. The concept is based on the application of a ZSM-5 zeolite with an initially high aluminium concentration which is exposed to steam under selected conditions to reduce its activity to a suitable level. The zeolite is then in a state where it suffers only very slow dealumination ensuring a more stable catalytic performance leading to a more uniform product composition.
Similar considerations apply in the production of light olefins for use as diesel or jet fuel.
Steam treatments - mainly of medium pore and, in particular, ZSM-5 type zeolites - were varied systematically by applying different contact times, temperatures and steam partial pressures. Selected zeolites were subjected to additional modifications either before or after steam treatment. All samples were characterised by physical, physico-chemical and chemical (catalytic) techniques. The development of these techniques was initiated at an early stage of the project and methods were refined throughout the research period.
TO OBTAIN AN IMPROVED UNDERSTANDING AT A FUNDAMENTAL LEVEL, OF THE PHENOMENA RELATING TO ZEOLITE STEAM DEALUMINATION AND TO STUDY THE ASSOCIATED CHANGES IN CATALYTIC PROPERTIES.
FURTHER OBJECTIVES COMPRISE THE USE OF ZEOLITE DEALUMINATION AS A MEANS OF TAILORING THE ACIDIC PROPERTIES OF ZEOLITES AND TO SEEK NEW APPLICATIONS OF DEALUMINATED ZEOLITES IN CATALYSIS.
WITHIN THE SCOPE OF THE PROJECT IS THE ESTABLISHMENT OF RELIABLE CHARACTERIZATION METHODS.
Campo scientifico (EuroSciVoc)
CORDIS classifica i progetti con EuroSciVoc, una tassonomia multilingue dei campi scientifici, attraverso un processo semi-automatico basato su tecniche NLP. Cfr.: Il Vocabolario Scientifico Europeo.
CORDIS classifica i progetti con EuroSciVoc, una tassonomia multilingue dei campi scientifici, attraverso un processo semi-automatico basato su tecniche NLP. Cfr.: Il Vocabolario Scientifico Europeo.
- ingegneria e tecnologia ingegneria ambientale gestione dei rifiuti processi di trattamento dei rifiuti riciclaggio
- scienze naturali scienze chimiche chimica inorganica composti inorganici
- scienze naturali scienze chimiche chimica organica alcoli
- scienze naturali scienze chimiche catalisi
- ingegneria e tecnologia ingegneria ambientale energia e carburanti
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Programma(i)
Programmi di finanziamento pluriennali che definiscono le priorità dell’UE in materia di ricerca e innovazione.
Programmi di finanziamento pluriennali che definiscono le priorità dell’UE in materia di ricerca e innovazione.
Argomento(i)
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Dati non disponibili
Gli inviti a presentare proposte sono suddivisi per argomenti. Un argomento definisce un’area o un tema specifico per il quale i candidati possono presentare proposte. La descrizione di un argomento comprende il suo ambito specifico e l’impatto previsto del progetto finanziato.
Invito a presentare proposte
Procedura per invitare i candidati a presentare proposte di progetti, con l’obiettivo di ricevere finanziamenti dall’UE.
Dati non disponibili
Procedura per invitare i candidati a presentare proposte di progetti, con l’obiettivo di ricevere finanziamenti dall’UE.
Meccanismo di finanziamento
Meccanismo di finanziamento (o «Tipo di azione») all’interno di un programma con caratteristiche comuni. Specifica: l’ambito di ciò che viene finanziato; il tasso di rimborso; i criteri di valutazione specifici per qualificarsi per il finanziamento; l’uso di forme semplificate di costi come gli importi forfettari.
Meccanismo di finanziamento (o «Tipo di azione») all’interno di un programma con caratteristiche comuni. Specifica: l’ambito di ciò che viene finanziato; il tasso di rimborso; i criteri di valutazione specifici per qualificarsi per il finanziamento; l’uso di forme semplificate di costi come gli importi forfettari.
Coordinatore
NAMUR / NAMEN
Belgio
I costi totali sostenuti dall’organizzazione per partecipare al progetto, compresi i costi diretti e indiretti. Questo importo è un sottoinsieme del bilancio complessivo del progetto.