{'fraction_non_alphanumeric': 0.03474576271186441, 'fraction_numerical': 0.05084745762711865, 'mean_word_length': 4.677884615384615, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Efficient two-stage laser enrichment up to 99% of carbon-13 isotope by IR multiphoton dissociation of Freon molecules

A new method for two-stage laser enrichment of carbon-13 (13C) by isotope-selective IR multiphoton dissociation of Freon molecules is considered, which makes it possible to achieve a concentration of 13C up to 99 % or higher with high productivity. At the first stage, as a result of the selective dissociation of CF2HCl (Freon-22) molecules, it is expected to obtain a C2F4 dissociation product enriched in 13C up to 30 % – 50 %. At the second stage, CF2Br2 (Freon-12B2) is proposed to be used as a working substance, which is synthesised from enriched C2F4, and the enrichment process is carried out by selective deep ‘burning-out’ of the 12C-containing component. Experiments on multiphoton dissociation of Freon-12B2 with an initial 13CF2Br2 concentration of 30 % in a mixture with oxygen by pulsed CO2 laser radiation are performed. It is shown that reaching a 13CF2Br2 concentration of no lower than 99 % is possible at high values of the elementary separation act parameters: 15 % – 18 % dissociation yield and 40 – 75 selectivity for 12CF2Br2 molecules.