# Adsorption Studies of Dilute Krypton and Xenon from Nitrogen on SBMOF‑1 and Activated Charcoal for Applications in Isotope Harvesting

## TL;DR

This study explores how well SBMOF-1 and activated charcoal can capture krypton and xenon gases from nitrogen, which is important for harvesting rare isotopes.

## Contribution

The study experimentally determines adsorption properties of Kr and Xe on SBMOF-1 and activated charcoal for isotope extraction.

## Key findings

- SBMOF-1 and activated charcoal show potential for noble gas extraction from FRIB effluents.
- The enthalpy of Kr adsorption on SBMOF-1 was measured as −19 ± 1 kJ·mol–1.
- Partition coefficients were used to estimate isotope extraction rates at FRIB.

## Abstract

Adsorptive partitioning of dilute krypton (Kr) and xenon
(Xe) onto
Stony Brook Metal–Organic Framework (SBMOF-1) and activated
charcoal (AC) from carrier nitrogen was experimentally measured at
temperatures ranging from 195 to 293 K. For this purpose, a closed-loop
system for gas adsorption experiments was developed. From the Kr adsorption
measurements, the adsorption equilibrium constant for Kr on SBMOF-1
was calculated, yielding a value for the enthalpy of adsorption of
−19 ± 1 kJ·mol–1. The partition
coefficients were utilized to estimate the extraction rates of 76Kr, 77Kr, and 122Xe isotopes during
isotope harvesting at the Facility for Rare Isotope Beams (FRIB).
We conclude that both materials showed promising results for the extraction
of noble gases from FRIB effluents using temperature swing adsorption.