RT Conference Proceedings
T1 Role of oxygen in the dehydration of methanol and ethanol  on carbon-based acid catalysts
A1 Valero-Romero, María José
A1 Calvo-Muñoz, Elisa Maria
A1 Rodrigues-Gómes, Marilucía
A1 Serrano-Pérez de Gracia, Marta
A1 Rodríguez-Mirasol, José
A1 Cordero-Alcántara, Tomás
K1 Carbón activado
K1 Catálisis
AB Activated carbons are receiving great attention in the last decades as catalysts and catalyst supports due to some advantages, such as, their very high specific surface area, high thermal and chemical stability and the presence of stable basic and acid surface sites as oxygen surface groups. We havepreviou sly reported the preparation and characterization of activated carbons by chemical activation of different lignocelullosic waste and by-products with phosphoric acid [1,2]. The carbons obtained showed a particular surface chemistry due to acid surface phosphorus groups of high thermal stability that remain over the carbon surface, providing the carbons a high oxidation resistance and surface acidity.In this work, we study the catalytic conversion of ethanol and methanol over an acid carbon-basedcatalyst obtained by chemical activation of olive stone with H3PO4. The carbon catalyst is active for both reactions, yielding mainly dehydration products, that is, dimethyl ether (SDME>82% at 350ºC) and ethylene (Sethylene>91% at 325ºC), with lower amounts of diethyl ether, for methanol and ethanol decomposition, respectively. The activated carbon catalytic activity and stability, under inert and oxidant atmospheres, as well as, different regeneration procedures were analyzed. Results evidence that catalytic performance strongly depends on the type of atmosphere in which the reaction proceeds and suggest that oxygen would play a key role on theses catalytic processes. In the absence of oxygen, catalyst suffers a progressive deactivation by coke deposition on the active acid sites, being faster and more pronounced for methanol decomposition (Fig. 1). However, in the presence of air, the carbon surface chemistry is modified, probably through oxygen spillover on the catalyst surface, where the availability of labile oxygen would inhibit catalyst deactivation and allow steady state conditions to be reached. Furthermore, the presence of oxygen leads to significant enhancements of both alcohol conversions and could even partially regenerate the catalyst.
YR 2014
FD 2014-07-28
LK http://hdl.handle.net/10630/7939
UL http://hdl.handle.net/10630/7939
LA eng
NO Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
DS RIUMA. Repositorio Institucional de la Universidad de Málaga
RD 21 ene 2026