Use of stable isotopes of CO2 to validate cylinder preparation

US11920732B2 · kind B2 · utility

Assignees

• Airgas, Inc. · US
• American Air Liquide, Inc. · US
• L'Air Liquide, Societe Anonyme Pour l'Etude et l'Exploitation des Procedes Georges Claude · FR

Inventors

• Tracey Jacksier · Lisle, US
• Mani C. Matthew · Neshanic Station, US
• Richard A. Socki · Nonatum Mills, US
• Jun Sonobe · Ibaraki, JP
• Megumi ISAJI · Yokosuka, JP
• James McHale · Fryeburg, US

Key dates

• Filing date: Mar 2, 2020
• Grant date: Mar 5, 2024
• Expiry date: Jan 5, 2043

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N2015/0866
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A quality control method for the preparation of dry compressed gas cylinder including passivating and/or preparing the compressed gas cylinder with the technique to be validated, filling the passivated/prepared compressed gas cylinder with gaseous carbon dioxide to a normal working pressure, wherein the gaseous carbon dioxide has a known δ18O isotope ratio, maintaining the pressurized gas cylinder at ambient temperature for a first predetermined period of time, and gradually emptying the pressurized gas cylinder, while simultaneously measuring the δ18O isotopic ratio, wherein a predetermined variation in the measured isotopic ratio of δ18O indicates a properly prepared cylinder.