Repositori URV

Identifier: TDX:1000

Handle: https://hdl.handle.net/20.500.11797/TDX1000

Authors:
González Candela, Mª Dolores

Abstract:
There is an increasing interest in searching new processes to transform glycerol (surplus in the biodiesel manufacture) into high-added value products. In addition, the use of microwaves for the synthesis and modification of materials is becoming an important tool to reduce the synthesis time (energy saving). In this thesis, we prepared, modified and characterized three zeolites, a zeolite with hierarchical porosity, an aerogel and a liogel of silica and ordered mesoporous materials to be tested as new heterogeneous catalysts for the glycerol etherification with tert-butanol or isobutene to obtain selectively di- and tri-ethers of glycerol (h-GTBE), which can be used as fuel additives. Other important objective of this thesis was to study the effect of using microwaves during dealumination of three zeolites on their resulting surface and acidic properties and during sulfonation of zeolites, montmorillonite K-10, aerogel, and liogel of silica and ordered mesoporous materials. The incorporation of sulfonic groups into these materials resulted in higher conversion (100 %) and higher selectivity (91 %) to desired products than non-functionalized materials.