Experimental verification of hydrogen isotope enrichment process by dual-column pressure swing and temperature swing adsorption

Highlights: • A vacuum pressure and temperature swing adsorption process was presented to enrich (separate) hydrogen isotopes, in which two identical separation columns and a transfer bump is used to improve the enrichment (separation) performance. • The presented process was quantitatively compared with other hydrogen isotope chromatographic separation processes, based on three technical indicators: enrichment factor, recovery rate and daily treatment capacity. Aiming to efficiently enrich heavier hydrogen isotope on a large scale, a process named Dual-Column Vacuum Pressure and Temperature Swing Adsorption (DC-VPTSA) was proposed and experimentally tested. The process has the following characteristics: 1) two identical separation columns work together; 2) Pressure Swing Adsorption (PSA) process and Temperature Swing Adsorption (TSA) process are coupled; 3) the gas always keeps one-way flow in different separation columns; 4) the process is always carried out under low temperature or low pressure condition. To verify the feasibility of the process, an experimental device was set up and the hydrogen isotopes enrichment performance was tested. The experimental results show that the process can steadily and efficiently enrich D₂ from H₂. For a H₂-HD-D₂ mixture with 3.63 at.% of D₂ abundance, the enrichment factor reaches about 19.7 and the recovery ratio is better than 99%. The treatment ability reaches a level of 560 SL/day under the condition of the individual column capacity of 71.5 SL. Compared with other processes, the presented process is superior in treatment ability, enrichment factor and recovery ratio.