Tech at Polsky

A New Method of Isotope Enrichment and Separation: Preferential Embedding of Heavier Isotopes Into Ices

Inventor(s):

Technology Classifications > Materials Technology Classifications > Other Technology Classifications > Research Tools

Download as PDF

SUMMARY

Isotope separation methods are key to numerous scientific and industrial processes. Nuclear power plants and weapons, for example, require fuels enriched in a select isotope. And isotopically pure or enriched samples are used in scientific research and medical procedures. Isotopes can be separated via fractional distillation, gaseous diffusion, and centrifugation. The process can also be driven by chemical, magnetic, and electrostatic methods. But these techniques are often energy intensive and require many sequential separation steps.
Gaseous diffusion, distillation and gas centrifuges exhibit small isotopic separation effects that are overcome through large-scale installations where many separation stages are performed in sequence. Alternatively, a variety of laser-based techniques exist that are capable of separating isotopes to a much higher degree, but require ionization or excitation of the target isotope.
The faculty inventor developed a new method for isotope separation involving the embedding of atoms and molecules into ice. Specifically, the method is based upon isotope dependent embedding preferentially capturing heavier isotopes and isotopologues in a cryogenic water ice matrix in which the isotopes and isotopologues are entrained in a velocity controlled molecular beam and then collide with the capture matrix which exhibits excellent single-pass enrichment.
Cycling of these single-step enrichment events for all methods can lead to significantly higher levels of purification, and routes to scale-up can be realistically envisioned. This method holds significant promise to be quite general in applicability, including both atomic isotopes and molecular isotopologues across a wide range of particle masses spanning, essentially, the periodic table.

FIGURE

A schematic example of our predicted embedding probabilities for 136Xe, 134Xe, and 129Xe versus incident momentum for one incident beam condition where all isotopes are entrained into the supersonic flow with the same velocity. The heavier isotopes systematically embed with higher probabilities into the ice capture matrix. See text for further details of the embedding experiments.

(Right) The ratios of 134Xe and 136Xe relative to 129Xe versus the average velocity of the Xe beam. The points labeled either Xe scattering or Xe TPD are the ratios measured by the detector when we made the null experiments as described in the Experimental section. The pink line is the average. The black circles are the data from the embedding measurements, and the black line is the average of these measurements.

ADVANTAGES

New and general method for isotope enrichment and purification based upon gas-surface encounters
Exhibits significant single-pass efficacy which can be incorporated into multiple stages to achieve high levels of purification
Scalability

APPLICATIONS

Production of medically important isotopes
Nuclear reactors for electricity generation
Isotopically-purified materials that exhibit high-performance electronic and thermal characteristics
Isotopically-purified spin-free materials for use in quantum information science platforms

PUBLICATIONS

K. D. Gibson and S. J. Sibener. A new method of isotope enrichment and separation: preferential embedding of heavier isotopes of Xe into amorphous solid water. Phys. Chem. Chem. Phys., 2021, 23, 7902

TECH DETAILS

Published
11/8/2023

Reference ID
21-T-042