Cryogenic Distillation Column for Isotope Enrichment

The distillation column was constructed to separate germanium isotopes. However, during the start-up phase of operation, the building changed hands and we were required to move the column on short notice. As our priorities changed, we never used it for separating germanium isotopes. It could theoretically be used for any cryogenic distillation where the materials are compatible with stainless steel.

The stainless steel column itself is 39 feet long and 9 ½ inches in diameter. It is dissembled in 2 sections: 19’ 8” and the other is 20’ 1 ½”.

The actual distillation column has a diameter of 1 inch, and it is surrounded by a vacuum jacket that is 4 inches in diameter. In addition, you need space of about 5 feet in diameter to assemble the refrigeration head in the condenser area. It would be good to have 5 to 6 feet above the assembly (including condenser) in case you had to modify or repair the assembly.

In order to have the column exactly vertical, I suggest a chain pulley above the assembled column, so that you can move the assembled column straight and keep it absolutely vertical. The pulley and chains could be included with the column.

While installed, we had an electric back-up generator system to prevent the collapse of the equilibrium in case of a power outage. In addition, we had an empty tank under vacuum to collect the gas should the cooling be interrupted and collection of the gas from the column be necessary.

When the owner of the building where the column was installed sold the building and asked us to move on short notice, we hurriedly disassembled the column. During this process a little bit of the vacuum oil was sucked into the upper part of the column. The vacuum oil can easily be washed out with an appropriate solvent.

The price: I am looking for $20,000 for the complete assembly (parts) necessary to run the column, including: the column and the compressor, various valves, and tubes.

I have enclosed pictures of the column and the assembly.

The compressor is a CTI-Cryogenics, model name 8200 Compressor. Approximate dimensions 16.65” h x 19.50”w x 19.59”d (423mm h x 495.3mm w x 498mm d)

Cryogenic Distillation Column
Cryogenic Distillation Column
Cryogenic Distillation Column

For more information please contact Mr. Barry Johnson, (603) 635-2255 or email