The Thermal Cycle Adsorption Separation Of Hydrogen Isotopes

Among all hydrogen isotope separation technologies, Thermal Cycling Absorption Process (TCAP), a semi-continuous hydrogen isotope separation process, is of many unique advantages. The basic principle of TCAP, the preparation, activation and property tests of Pd/K packing material in the separation column were summarized. TCAP system designed in this work mainly consists of a separation column, feeding and withdrawing subsystem, column cooling and heating subsystem, data collection and autocontrol subsystem. About 901g Pd/K was packed in the column. The palladium content of the Pd/K whose particle sizes were 40⁶0mesh was about 40.8wt%. The hydrogen absorption capacity of the column was 27016ml (STP) .The system was tested in total reflux mode with hydrogen-deuterium mixtures at different operation parameters including initial feeding ratio, cooling or heating temperatures, feeding place of raw gases in order to confirm the best operation conditions of hydrogen isotope separation. The technical process and key parameters of TCAP system have been confirmed and optimized based on large numbers of experiment data. The results showed that the higher initial feeding ratio and temperature difference of the column were, the better the separation effects would be when feeding at the central point of the column. If the gases were fed from the Plug-Flow Reverser (FTR), the separation results would be better. When raw gas mixture with 48.5%H2-51.5%D2 was fed 90% into the column from the FTR with cooling at 56℃and heating at 290℃, deuterium content in the product was between 98%-99% and reached 99.2% after 30 cycles. Protium content in the raffinate and separation factor was 96.1% and 3055.49 respectively after 60 cycles.Separation of protium and deuterium had also been done in on-line mode with the parameters of initial feeding of 90%, feeding and withdrawing of 3% during separation, cooling the column at 21 ℃ and heating at 290℃ in order to validate the separation capacity of TCAP. If the raw gases were 47.5%H2-52.5%D₂, protium content in the raffinate was 71.5% and 76.9% after 7 and 12 cycles, respectively. Deuterium concentration in the product was 97.6% and 98.1% after 7 and 12 cycles, while separation factors were 102.02 and 171.88 after 7 and 12 cycles. The results indicated that the system could separate about 2.47mol/day hydrogen isotope with feeding and withdrawing of 3% after every cycle in on-line mode. It...