title: Cryogenic distillation facility for isotopic purification of protium and deuterium.
abstract: Isotopic purification of the protium and deuterium is an important requirement of many physics experiments. A cryogenic facility for high-efficiency separation of hydrogen isotopes with a cryogenic distillation column as the main element is described. The instrument is portable, so that it can be used at the experimental site. It was designed and built at the Petersburg Nuclear Physics Institute, Gatchina, Russia. Fundamental operating parameters have been measured including a liquid holdup in the column packing, the pressure drops across the column and the purity of the product at different operating modes. A mathematical model describes expected profiles of hydrogen isotope concentration along the distillation column. An analysis of ortho-parahydrogen isomeric composition by gas chromatography was used for evaluation of the column performance during the tuning operations. The protium content during deuterium purification (≤100 ppb) was measured using gas chromatography with accumulation of the protium in the distillation column. A high precision isotopic measurement at the Institute of Particle Physics, ETH-Zurich, Switzerland, provided an upper bound of the deuterium content in protium (≤6 ppb), which exceeds all commercially available products.
authors.affiliation: National Research Center "Kurchatov Institute" Petersburg Nuclear Physics Institute (NRC "Kurchatov Institute" PNPI), 188300 Gatchina, Russia.
authors.forename: I
authors.initials: I
authors.lastname: Alekseev
authors.affiliation: National Research Center "Kurchatov Institute" Petersburg Nuclear Physics Institute (NRC "Kurchatov Institute" PNPI), 188300 Gatchina, Russia.
authors.forename: Ev
authors.initials: E
authors.lastname: Arkhipov
authors.affiliation: National Research Center "Kurchatov Institute" Petersburg Nuclear Physics Institute (NRC "Kurchatov Institute" PNPI), 188300 Gatchina, Russia.
authors.forename: S
authors.initials: S
authors.lastname: Bondarenko
authors.affiliation: National Research Center "Kurchatov Institute" Petersburg Nuclear Physics Institute (NRC "Kurchatov Institute" PNPI), 188300 Gatchina, Russia.
authors.forename: O
authors.initials: O
authors.lastname: Fedorchenko
authors.affiliation: National Research Center "Kurchatov Institute" Petersburg Nuclear Physics Institute (NRC "Kurchatov Institute" PNPI), 188300 Gatchina, Russia.
authors.forename: V
authors.initials: V
authors.lastname: Ganzha
authors.affiliation: National Research Center "Kurchatov Institute" Petersburg Nuclear Physics Institute (NRC "Kurchatov Institute" PNPI), 188300 Gatchina, Russia.
authors.forename: K
authors.initials: K
authors.lastname: Ivshin
authors.affiliation: Department of Physics, University of Washington, Seattle, Washington 98195, USA.
authors.forename: P
authors.initials: P
authors.lastname: Kammel
authors.affiliation: National Research Center "Kurchatov Institute" Petersburg Nuclear Physics Institute (NRC "Kurchatov Institute" PNPI), 188300 Gatchina, Russia.
authors.forename: P
authors.initials: P
authors.lastname: Kravtsov
authors.affiliation: Paul Scherrer Institut (PSI), CH-5232 Villigen, Switzerland.
authors.forename: C
authors.initials: C
authors.lastname: Petitjean
authors.affiliation: National Research Center "Kurchatov Institute" Petersburg Nuclear Physics Institute (NRC "Kurchatov Institute" PNPI), 188300 Gatchina, Russia.
authors.forename: V
authors.initials: V
authors.lastname: Trofimov
authors.affiliation: National Research Center "Kurchatov Institute" Petersburg Nuclear Physics Institute (NRC "Kurchatov Institute" PNPI), 188300 Gatchina, Russia.
authors.forename: A
authors.initials: A
authors.lastname: Vasilyev
authors.affiliation: National Research Center "Kurchatov Institute" Petersburg Nuclear Physics Institute (NRC "Kurchatov Institute" PNPI), 188300 Gatchina, Russia.
authors.forename: T
authors.initials: T
authors.lastname: Vasyanina
authors.affiliation: National Research Center "Kurchatov Institute" Petersburg Nuclear Physics Institute (NRC "Kurchatov Institute" PNPI), 188300 Gatchina, Russia.
authors.forename: A
authors.initials: A
authors.lastname: Vorobyov
authors.affiliation: National Research Center "Kurchatov Institute" Petersburg Nuclear Physics Institute (NRC "Kurchatov Institute" PNPI), 188300 Gatchina, Russia.
authors.forename: M
authors.initials: M
authors.lastname: Vznuzdaev