Purification

Why do we need purification?

Searching for the rare events like the neutrinoless double beta decay and the dark matter interactions for the proposed experiments requires to use developed detectors made from initial materials with extremally low internal radioactive background. So, purification of materials used for the detectors is one of important direction for R&D program of CUP.

How do we purify?

We use various purification techniques for reduction of radioactive contamination in 100MoO3 powder, as a main initial material for the AMoRE detector, and in NaI powder, as a main initial material for the COSINE detector.

For purification of molybdenum tri-oxide, we apply combination of sublimation with wet chemistry techniques using home-made sublimation and annealing machines for producing of final product:

For purification of sodium iodide, we have designed developed mass-scale purification facility based on the fractional recrystallization from water:

How do we check purity of our products?

We use Inductively Coupled Plasma Mass Spectrometer Agilent 7900 for trace level analysis of our materials and products. The use of ICP-MS method conducted with UHMI and He modes provides high precise and accurate measurement of many elements, like Th, U, Ba, Sr, Pb, K, etc. on a ppt level.