Laser Spectroscopy for Monitoring of Radiocarbon in Atmospheric Samples

In-situ monitoring of radiocarbon emissions is challenging due to the lack of a suitable method for sensitive online detection of this isotope. Here we report on a complete system for automatized continuous on-site monitoring of radiocarbon gaseous emissions from nuclear facilities. By combining radiocarbon detection using mid-infrared cavity ringdown spectroscopy and an advanced sampling system, an elevated amount of radiocarbon in an atmospheric-like gas matrix was detected. Radiocarbon was detected in the form of (CO2)-C-14 after extraction of the carbon dioxide from the air sample. The system is also able to discriminate between radiocarbon in organic or inorganic molecular form by converting (CH4)-C-14 into (CO2)-C-14. This work lays the groundwork for further use of this technology in nuclear facilities for online on-site monitoring of radioactive gaseous emissions as well as future work on in-situ monitoring of atmospheric radiocarbon.Peer reviewe

A method of selectively catalytically oxidizing dinitrogen oxide, a method of detecting radiocarbon, an apparatus, and use of a NiO catalyst

A method of selectively catalytically oxidizing dinitrogen oxide present in a gaseous sample, comprising: heating a NiO catalyst to a temperature of at least 250 °C; and bringing the gaseous sample into contact with the heated NiO catalyst to oxidize dinitrogen oxide of the gaseous sample in the presence of the heated NiO catalyst.Patent family as of 22.12.2021EP3856394 A1 20210804 EP20190783580 20190924      FI128390 B 20200415 FI20180005800 20180926      FI20185800 A 20200327 FI20180005800 20180926      WO20065133 A1 20200402 WO2019FI50686 20190924Link to currentpatent family on right </p

On-Line Monitoring of Radiocarbon Emissions in a Nuclear Facility with Cavity Ring-Down Spectroscopy

[Image: see text] There are currently no suitable methods for sensitive automated in situ monitoring of gaseous radiocarbon, one of the main sources of radioactive gas emissions from nuclear power plants. Here, we present a transportable instrument for in situ airborne radiocarbon detection based on mid-infrared cavity ring-down spectroscopy and report its performance in a 1-week field measurement at the Loviisa nuclear power plant. Radiocarbon is detected by measuring an absorption line of the (14)CO(2) molecule. The time resolution of the measurements is 45 min, significantly less than the few days’ resolution of the currently used technique, while maintaining a comparable sensitivity. The method can also assess the prevalence of radiocarbon in different molecular species in the airborne emissions. The optical in situ monitoring presented is a completely new method for monitoring emissions from nuclear facilities