Thulium (Tm): Nuclear Reactor Control Material, Activator for Phosphors, High-Temperature Superconductor

Thulium (Tm) is a silver-white metal with ductility and relatively soft texture. It has a melting point of 1545°C, a boiling point of 1950°C, and a density of 9.320 g/cm³. Thulium remains stable in air.

Applications

1. Used as a control material in nuclear reactors.
2. Can act as an activator for certain fluorescent materials.
3. Also serves as a high-temperature superconducting material.

Product Series

Health and Safety Information

Signal Word	Danger
Hazard Statements	H228-H319-H335
Hazard Codes	F, Xi
Precautionary Statements	P210-P261-P305 + P351 + P338
Flash Point	N/A
Risk Codes	N/A
Safety Statements	N/A
RTECS Number	N/A
Transport Information	NONH
WGK Germany	3
GHS Pictograms

Packaging Specifications

• Standard packaging: 50 kg/drum, 500 kg/pallet, ton bags
• Sample packaging: 500 g/bag, 1 kg/bottle

Production of Thulium Metal

After separating thulium from other rare earth elements via ion exchange or solvent extraction techniques, metallic thulium can be prepared through metallothermic reduction. Unlike calcium reduction of rare earth chlorides, lithium reduction occurs in the vapor phase.

The lithium reduction reactor consists of two heating zones, with the reduction and distillation processes carried out in the same equipment. Anhydrous thulium chloride (TmCl₃) is placed in the upper titanium crucible (also the TmCl₃ distillation chamber), while the reducing agent, lithium metal, is placed in the lower crucible. The stainless steel reaction vessel is then evacuated to 7 Pa before heating begins.

When the temperature reaches 1000°C, it is maintained for a period to allow thorough reaction between TmCl₃ vapor and lithium vapor. The resulting solid thulium metal particles collect in the lower crucible. After completion of the reduction, only the lower crucible is heated to distill LiCl into the upper crucible. The entire reduction process typically takes around 10 hours.

To obtain high-purity thulium metal, the reducing agent lithium must be 99.97% pure, and twice-distilled anhydrous TmCl₃ is used.