Removal of CF4 from NF3 at the Phase Interface
Научная публикация
| Общая информация |
Язык:
Английский,
Жанр:
Статья (Full article),
Статус опубликования:
В печати (In Press),
Оригинальность:
Оригинальная
|
| Журнал |
Journal of the Taiwan Institute of Chemical Engineers
ISSN: 1876-1070
|
| Вых. Данные |
Год: 2021,
Номер статьи
: 104178,
Страниц
: 6
DOI:
10.1016/j.jtice.2021.104178
|
| Ключевые слова |
Close boiling points; Industrial application; Nitrogen trifluoride; Phase boundary; Purification; Separation method |
| Авторы |
Cholach Alexander
1
,
Yakovin Dmitri
2
|
| Организации |
| 1 |
Boreskov Institute of Catalysis, Akademik Lavrentiev Ave 5, Novosibirsk 630090, Russia
|
| 2 |
Institute of Automation and Electrometry, Akademik Koptyug Ave 1, Novosibirsk 630090, Russia
|
|
Информация о финансировании (1)
|
1
|
Министерство науки и высшего образования Российской Федерации
|
0239-2021-0002
|
Background The close boiling points of carbon tetrafluoride (CF4) and nitrogen trifluoride (NF3) and the chemical inertness of CF4 make it difficult to remove it from NF3.
Methods A method for cleaning NF3 from CF4 at the gas-liquid interface is proposed. The purification is carried out by a sequence of cycles: (1) fractional condensation of NF3 at a cryostat temperature (TCry), at which the equilibrium pressure of CF4 exceeds its partial pressure in the feed mixture; and (2) pumping out the gas phase enriched with CF4 and high-boiling impurities. The cycles are repeated at a next TCry corresponding to the new CF4 content, and are completed by cryogenic distillation of the condensate with the removal of low-boiling impurities.
Findings The CF4 content of 5000 ppm in a 25 g NF3 sample was reduced to less than 100 ppm in three cycles at TCry = 120 K; a CF4 separation coefficient above 40 was achieved. The method can be used for the industrial production of high-purity NF3, with the cryostat refrigerant being the only consumable material, as well as for the separation of other substances with close boiling points, such as isomers or isotopes. © 2021 Taiwan Institute of Chemical Engineers