| dc.description.abstract | Rare earth elements (REEs) are lanthanide elements widely used in high-tech electronic equipment. In this study, REEs from earth minerals were enriched through several stages, namely destruction, extraction by microwave oven, and precipitation. The dry and wet destruction phases by using NaOH produced a total of 25.56% and 44.30% REEs, respectively. At the extraction by microwaves stage with HCl 37% as solvent, REEs were successfully dissolved in 30 minutes at high energy. Total amount of REEs which contained in the liquid phase from wet and dry destruction were 35.72% and 29.97%, respectively. Precipitation of REEs started when the pH value was higher than 7, reached by using NH4OH 2 N. Total precipitated REEs in wet and dry feed destruction at pH 10 was 2.76% and 1.18%, respectively. Precipitation at pH 10 gave the highest total REEs. Dry feed destruction produced precipitate that effectively enrich REEs by decreasing impurity elements, such as Si and P, and there was no Th element found. It is also contained low U element which was only 12 ppm. This is consistent with the value of percent recovery and the non-radioactive REEs which was smaller than the wet feed destruction, but contains elements of U in the amount of not less than 0.00006 g and without Th element. | en |
