Tijek kristalizacije aluminijevih oksida iz gelova s različitim udjelom kelata

undergraduate thesis

• Title (english): Crystallization path of aluminum oxides from gels with various shares of chelate
• Author: Matej Zlatar
• Mentor: Stanislav Kurajica (mentor)
• Committee member: Stanislav Kurajica (predsjednik povjerenstva)
• Committee member: Nevenka Vrbos (član povjerenstva)
• Committee member: Danijela Ašperger (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2017-09-20, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Basic Technical Sciences; Materials

Abstract

Aluminijevi oksidi široko se koriste kako u znanosti, tako i u industriji. Imaju mnogobrojne primjene u katalizi i keramici, te kao membrane i adsorbensi zbog svojih dobrih kemijskih, mehaničkih i fizikalnih svojstva. Provedbom infracrvene spektroskopije s Fourierovom transformacijom (FTIR), rendgenske difrakcijske analize (XRD) te diferencijalne toplinske i termogravimetrijske analize (DTATGA) istražen je tijek kristalizacije aluminijevih oksida. Aluminijevi oksidi su pripremljeni iz gela koji je dobiven sol-gel metodom iz aluminijevog sec-butoksida keliranog s etil acetoacetatom u različitim omjerima. Uzorci su termički obrađeni u visokotemperaturnoj peći pri temperaturama od 200 do 1200 °C. Iz podataka dobivenih eksperimentalnom analizom uočljivo je da se temperatura kristalizacije γ-Al2O3 pomiče sa 800 na 1000 °C s povećanjem molarnog omjera Eaa/Asb. Također, za uzorke s omjerom etil acetoacetate i aluminijeva sec butoksida od 2.0, 2.5, 3.0 opažen je nastanak kelata tris (etil acetoacetata) aluminija (III), koji je otporan na hidrolizu.

Abstract (english)

Aluminium oxides are used in science and industry with numerous applications such as catalysis, membranes, adsorbents and ceramics, because of their good chemical, mechanical and physical properties. Using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Differential thermal and thermogravimetric analysis (DTA-TGA), the crystallization process of aluminium oxide has been investigated. Aluminium oxide was prepared from gels obtained by the sol-gel method using aluminium sec-butoxide chelated with ethyl acetoacetate in various ratios. Gels were dryed and then thermally treated in a high temperature furnace within the temperature range from 200 to 1200 °C. From the data obtained by experimental analyses, it was shown that the crystallization temperature of γ-Al2O3 shifts from 800 °C to 1000 °C with increment of the molar ratio of Eaa/Asb. In addition, formation of the chelate tris (ethyl acetoacetate) aluminium (III), which is resistant to hydrolysis, for samples with ethyl acetoacetate to to aluminium sec-butoxide ratio of 2.0, 2.5 and 3.0 was observed.

• Keywords: aluminijev oksid; keliranje; kristalizacija; sol-gel
• Keywords (english): aluminium oxide; chelation; crystallization; sol-gel
• Language: croatian
• URN:NBN: urn:nbn:hr:149:092765
• Study programme: Title: Materials Science and Engineering - Undergraduate study; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka kemijskog inženjerstva (sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka kemijskog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2021-03-15 11:04:25