Journal of the Korean Society of Mineral and Energy Resources Engineers ISSN:2288-0291(Print) 2288-2790(Online) 한국자원공학회지

For the purpose of a fundamental study on the flotation recovery of precious metals from dental material waste, zeta potential and contact angle of dental materials were measured. The XRD analysis and image analysis of the dental material waste used in this study showed the patterns of gypsum, quartz, corundum, carborundum, aluminum magnesium silver, and aluminum gold. The zeta potentials of corundum, carborundum, gold and platinum as standard sample have been measured as a function of pH. Their isoelectric points were found to be at pH 8.5, 4.6, 3.6, and 3.2, respectively. It is suggested that the charge on gold and platinum particles among dental material waste have the opposite sign to that of corundum and carborundum particles as abrasives among dental material waste in the range pH 3.6 to 4.6. The contact angles of the dental alloy containing 90wt% gold and 56wt% gold are 80.3 degree and 65.7 degree, respectively. Therefore, it would be possible to make gold and platinum particles more hydrophobic by a cationic collector in the range pH 3.6 to 4.6.