Tesis doctoral de Sonia Abello Cros
The research about the use of new solid brí¸nsted-type basic catalysts has been the focus of many recent studies because of their potential for aldol condensation reactions. Besides,these solid materials avoid the industrially use of koh and naoh reducing severalproblems such as waste production, corrosion and not recovery of the catalysts.In recent years, there has been a growing interest in layered double hydroxides (ldh) orhydrotalcite-like compounds to perform numerous catalytic reactions and otherapplications. in order to provide solid brí¸nsted-type basic catalysts, a thermally treatedmg-al ldh can be reconstructed due to its known memory effect, by rehydration in contactwith water vapour or immersed in liquid water under decarbonated atmosphere. Thecatalytic performance of a reconstructed mg-al ldh in relation to the rehydrationprocedure applied is not well understood. In this work, careful studies of rehydrationprocedures (gas or liquid phase) over decomposed mg-al ldh have been performed.Since the rehydration process leads to a meixnerite-like material, having brí¸nsted basicsites in the interlayer space, it is shown that accessibility towards these basic sites is a key factor determining the performance of the catalysts in aldol condensation reactions.The sensitivity of gas-phase reconstructed mg-al ldh to the addition of alkaline promotershas been also studied to assess their influence on the catalytic performance. The researchdescribed in this thesis has focussed on getting more insight in the activation/rehydrationprocedure and consequently, in the final morphology of hydrotalcite-like compounds. Thebasic properties have been characterised by several techniques such as temperatureprogrammed desorption of different probe molecules and by illustrative test reactions such as the liquid-phase aldol condensation between citral-ketones.Another interesting alternative is the use of ionic liquids, which have attracted a largeattent
Datos académicos de la tesis doctoral «Síntesi i caracterització de materials bÁ sics i la seva aplicació en reaccions d`interés industrial«
- Título de la tesis: Síntesi i caracterització de materials bÁ sics i la seva aplicació en reaccions d`interés industrial
- Autor: Sonia Abello Cros
- Universidad: Rovira i virgili
- Fecha de lectura de la tesis: 25/11/2005
Dirección y tribunal
- Director de la tesis
- Francesc Medina Cabello
- Tribunal
- Presidente del tribunal: Sueiras romero Jesús eduardo
- didier Tichit (vocal)
- vicente Rives arnau (vocal)
- vasile Hulea (vocal)