Abstract | Aluminijev oksid (Al 2 O 3 ) ima široku primjenu u anorganskoj industriji zbog svojim izrazito povoljnih kemijskih i termičkih svojstava. Najpoznatija uporaba Al 2 O 3 je u procesu proizvodnje keramike (čisti Al 2 O 3 ili smjesa Al 2 O 3 i ZrC, ZnO 2 , SiC i dr.). Zbog svojih dobrih mehaničkih svojstava Al 2 O 3 se upotrebljava i kao abraziv te u staklenoj industriji kao vatrostalni materijal. Cilj ovog diplomskog rada je ispitati eksperimentalne uvjete sinteze (temperatura, utjecaj surfaktanta, vrijeme) čestica Al 2 O 3. U radu su primijenjene temperature sinteze u rasponu od 130°C do 250°C (130°C, 200°C i 250°C) za različito vrijeme sinteze od 20, 30 i 40 min i uz prisutnost miješanja ili bez miješanja tijekom mikrovalne sinteze. Od surfaktanata koji su korišteni, ispitan je utjecaj cetiltrimetilamonijeva bromida (CTAB) u količinama od 0,4 g i 1,0 g, polietilen glikola (PEG) u količinama 2 g, 1 g i 0,4 g, natrijva dodecil-sulfata (SDS) u količini od 1 g te N-gvanilurea sulfat u količini od 1 g. Svi uzorci snimljeni su IR-spektrometrom (FTIR). Odabrane uzorke, koji su pokazivali najbolje FTIR rezultate, žareni su pri temperaturama 400°C, 800°C i 1100°C. Duljina žarenja iznosila je 2 h odnosno 4 h. |
Abstract (english) | Due to its extremely favourable chemical and thermal properties, aluminum oxide has wide application in the inorganic industry. The most well-known use of Al 2 O 3 is in the process of ceramics production (as a pure Al 2 O 3 or as a mixture of Al 2 O 3 and ZrC, ZnO 2 , SiC etc.). Due to its good mechanical properties it is also used as an abrasive, but also in the glass industry as a refractory material. The goal of this master thesis is to examine the experimental conditions (synthesis temperature, annealing temperature, surfactant effect, synthesis time, mixing effect etc.) that would be most optimal for obtaining Al 2 O 3 particles. The thesis uses synthesis temperatures ranging from 130°C to 250°C (130°C, 200°C and 250°C) for different synthesis times (20 min, 30 min, 40 min) and the presence or the absence of mixing during microwave synthesis. Of the surfactants that were used, the influence of cetyl trimethylammonium bromide (CTAB) in quantities of 0,4 g and 1,0 g, polyethylene glycol in quantities of 2,0 g, 1,0 g and 0,4 g, sodium dodecyl sulfate in quantities of 1,0 g and N-guanylurea sulfate in quantities of 1,0g was examed. All sample were analyzed by FTIR. Selected samples, which had showed the best FTIR results, were subjected to the annealing process at respective temperatures of 400°C, 800°C and 1100°C. The annealing lenght was 2 h at 400°C and 4 h for annealing at 800°C and 1100°C, respectively. |