Synthesis and characterization of metal acid catalysts

Namen diplomske naloge je bil sintetizirati kovinsko kislinski katalizator s postopkom mokre impregnacije, ki bo skupaj s kovinskimi ioni funkcionaliziran mezoporozni silikatni nosilec. Učinkovitost katalizatorja smo preverjali z reakcijo esterifikacije miristinske kisline z metanolom. V začetku je bila kot nosilec kovinskih ionov predvidena mezoporozna silika SBA-15, kasneje smo sintetizirali mezoporozni nosilec MCM-41, ki se je z vezanimi kovinskimi Al3+ ioni izkazal za učinkovitega pri esterifikaciji. Z rezultati, dobljenimi z analizo vzorcev s HPLC, smo izračunali presnovo kisline v ester. Sledila je karakterizacija katalizatorja z metodami DLS, DSC, TGA, BET, FTIR in kemisorpcijo z NH3. Iz rezultatov karakterizacije Al-MCM-41 ugotavljamo, da je največja zastopanost delcev z velikostjo 642,2 nm, medtem ko je povprečna velikost 596,4 nm. Material ima specifično površino 828,17 m2 g-1 s premerom por 2,97 nm. Prisotna je funkcionalna skupina Si-O-Si. V katalizatorju razen vezane vode ni bilo zaznanih drugih primesi. Ugotovili smo, da ima katalizator srednje do močna aktivna kislinska mesta.The purpose of the diploma thesis was to synthesize a metal acid catalyst with a wet impregnation process, which together with metal ions will be a functionalized mesoporous silicate support. The efficiency of the catalyst was checked by the esterification reaction of myristic acid with methanol. Initially, mesoporous silica SBA-15 was envisaged as a metal ion carrier, then the mesoporous carrier MCM-41 was synthesized, which proved to be effective in esterification with bound metal Al3+ ions. Using the results obtained by analyzing the samples by HPLC, we calculated the metabolism of the acid to the ester. Catalyst characterization by DLS, DSC, TGA, BET, FTIR and chemisorption with NH3 followed. From the results of the characterization of Al-MCM-41, we find that the largest representation of particles is 642,2 nm, while the average size is 596,4 nm. The material has a specific surface area of 828,17 m2 g-1 with a diameter of 2,97 nm. The Si-O-Si functional group is present. No impurities other than bound water were detected in the catalyst. The catalyst was found to have medium to strong active acid sites