Reply To: YouTube Focus Fusion Video

[jamesr]

Rezwan wrote:

Separating Boron into B-10 & B-11 is done on an industrial scale already for conventional nuclear plants. I’m not sure what the cost is but it shouldn’t be significant in the whole scheme of things.

Do you have any links on this? The process, cost and safety concerns?

I think normally it is done by ion exchange chromatography. Here are a few links
Musashi et al, Column chromatographic boron isotope separation at 5 and 17 MPa with diluted boric acid solution (2008)
Song et al, Advances in boron-10 isotope separation by chemical exchange distillation (2009)

If you can’t access the paper directly here’s an extract where he discusses the history of boron separation (I’m useless at chemistry so don’t ask me what it all means!):

The separation of B-10 was started during World War II. Aether was originally selected as the donor ([Palko and Drury, 1961a], [Palko and Drury, 1961b], [Palko and Drury, 1964] and [Saxena et al., 1961]) and the process condition was: a glass distillation column with a height of 4 m and a diameter of 19 mm, and packing Dixon ring of 1.6 mm × 1.6 mm were adopted. The operation temperature was 70 °C and the pressure was 2.7 kPa at the top and 4.0 kPa at the bottom. The operation cycle lasted 88 days and the yield of B-10 was 2 kg/year with a mass purity of 83%. However, due to the irreversible decomposition of (C2H5)2O·BF3, the decomposition rate of the feed was 12% per day. Higher temperature (70 °C) and high vacuum were required in this process, which consequently limited the production capacity.

Later, aether was replaced with ether and the industrial equipment which can yield 300 kg B-10 (95%) per year was built (Conn and Wolf, 1958). The process condition was as follows: 9 cascaded columns made of Monel steel were adopted. The diameters of the first 3, the second 3 and the final 3 columns were 457.2 mm, 304.8 mm and 152.4 mm respectively. The columns had an average height of 8.33 m and were packed with Stedman Packing. The operation pressures and temperatures were 20 kPa/90 °C at the top and 38.7 kPa/104 °C at the bottom. Compared with the former donor aether, although the irreversible decomposition still existed, the decomposition rate of the feed was only 1.2% per day and the vacuum was allowed to be ten times lower. Production yield increased obviously, yet a certain degree of vacuum was still necessary.

At present, anisole, instead of ether, is widely used in the production of B-10. Compared with ether, anisole has a higher single stage separation coefficient. The process condition is as follows: the whole apparatus consists of four parts: the exchange column, the decomposer column, the recombination device and the solvent purification tank. The copper exchange column is 81.3 m high and operates at 25 °C and normal pressure. The decomposition rate decreases remarkably to only 0.01% in every operation circle.

Katalnikov (Frank, 1995) explored the kinetics and thermodynamics in the separation of B isotopes by chemical exchange distillation using complex anisole, and demonstrated two ways to improve the process: (1) operate at a high pressure so that the capacity of the column would be increased and the kinetics would be improved and (2) apply ideal temperature gradient technology to optimize the separation process. In the past few years, Weijiang Zhang, et al. ([Jiang et al., 2007], [Han et al., 2007], [Han et al., 2006], [Wang et al., 2006] and Yu et al., 2005 J.Y. Yu et al., A Mathematical model in separation of boron isotopes by chemical exchange reaction method, J. Isotopes 18 (4) (2005), pp. 216–219 196.[Yu et al., 2005]) experimentally studied problems such as decomposition reaction and evaluation of donors in chemical exchange distillation. Modeling and simulation were also carried out by them to illustrate and optimize the separation process, which provide an effective way for further studies.

Here is a company that does it currently: Ceradyne Inc