Leucite enrichment from phonolite and investigation of its use in ceramic applications

Daha sonIn this thesis study, the potential direct use of leucite mineral in the field of dental ceramics was investigated after its recovery from phonolite, a volcanic rock. In this context, the feasibility of obtaining leucite mineral with desired properties was examined using dry magnetic separation (Permoll), one of the ore beneficiation methods, from phonolite rock sourced from the Şuhut district of Afyon, Türkiye. Prior to magnetic separation, the phonolite rock was processed through a jaw crusher, a roller crusher, and a sieving process to prepare samples in two different particle size distributions (-1000-400 μm and -400-100 μm) for experimental studies. Before separation, chemical and mineralogical analyses were performed on the rock. In the magnetic separation studies, the effects of feed rate (m/s), blade angle (°), and belt speed parameters were evaluated within 54 different experimental setups designed using Design of Experiments (DOE) for two different particle size ranges. The chemical and mineralogical compositions of the magnetic, middling, and non-magnetic products obtained from each experiment were analyzed, with a particular focus on Fe₂O₃ and K₂O contents. As a result of the magnetic separation studies, the LM5NM2-coded non-magnetic product was determined to be the most suitable material for dental ceramic applications based on Fe₂O₃ and K₂O content. Subsequent dental ceramic experiments were conducted using this product. In the dental ceramic applications, four different dental ceramic formulations were prepared. In conventional dental ceramics, a fritting process is typically applied after the peak sintering temperature to obtain the crystalline leucite phase. However, since leucite was naturally present in this study, the fritting process was deemed unnecessary and was therefore omitted. The samples obtained from the four different dental ceramic formulations were analyzed in terms of chemical and mineralogical composition, thermal behavior using a heating microscope, particle size distribution, SEM imaging, and Vickers hardness measurements.ra doldurulacaktır.