Thulium: Oxide Reduced with Aluminium in Flowing Argon and the Vapour Condensed (CN 104152695 B)

Pellets of thulium oxide and aluminium are fed into an induction furnace at 1700 °C. The aluminium takes the oxygen and stays behind as slag. Thulium boils off as vapour, and a stream of argon carries it into a water-cooled tank where it condenses to metal. Result: thulium metal, 99.5 % of the thulium recovered. No vacuum pump is needed: the moving argon sweeps the vapour away as fast as it forms. Source: Zhang, Dou et al. (Northeastern University), Chinese patent CN 104152695 B (2014), Example 1. Not given: batch size, the form of the aluminium, pellet size, the purity of the thulium. Picture: Wikimedia Commons.

上級者

1 day

手順

Weigh and mix

Weigh thulium oxide and aluminium, both over 99.0 % pure, in the molar ratio 1 : 2.2: 10 % more aluminium than the reaction needs (ours: about 15.4 g of aluminium to 100 g of oxide). Mix them evenly.

このステップの材料:

酸化ツリウム100 g

必要な工具:

アルミニウム

はかり

Press into pellets

Press the mix in a roller press at 100 kg/cm² into lumpy pellets.

必要な工具:

ロールプレス

Reduce in flowing argon

Run argon (99.95 %) through a medium-frequency induction furnace (the patent's coil is 220 mm across) at 5 L/min; ours: set the flow with a rotameter. Feed the pellets in continuously and hold them at 1700 °C for 30 min. The thulium leaves as vapour mixed with the argon; draw the slag off continuously.

必要な工具:

誘導炉

アルゴン

ロータメーター

Condense the thulium

Let the argon carry the vapour out of the furnace through a sealed pipe straight into a condensing tank cooled by circulating water. The thulium condenses there as metal: 99.5 % recovered. Example 2 of the patent runs at 1500 °C for 60 min with 15 L/min of argon (pellets pressed at 150 kg/cm²) and reports 99.2 %.

必要な工具: