In autumn 2016, the Laboratory of Chronology received a fuel sample from an international client which was found to contain 2.7% biofuel. After consulting with the client, it was discovered that the company that had sent the sample had claimed that the ratio of biofuel in the fuel mix was 80%.
The determination of the ratio of biofuel in a sample is based on analysing the amount of radiocarbon (14C), which makes its way from the atmosphere into organisms.
All biomass – which is to say, all living things – accumulate radiocarbon through photosynthesis and the food chain. Once an organism dies, the radiocarbon stops accumulating and instead begins to degrade, becoming undetectable by the fossil stage. As biofuels are created from biological material, they always contain radiocarbon.
The biofraction is determined from the amount of material in the sample which still contains radiocarbon. The analysis can reveal, for example, the ratio of renewable bio-based diesel to fossil diesel in a fuel mix, or whether the ethanol in a bioethanol-petrol mix is truly biologically derived.
Biofraction determination can also be used to analyse the smoke emissions from power plants. A carbon dioxide sample from the smoke emissions from a smokestack can be used to establish how much biofuel has been burned by the power plant during a set period of time, or to determine the biofractions of bioplastics. In practice, the method can be used to analyse any material that contains carbon.
The significance of precise, reliable measuring methods will increase, as international climate policy emphasises the replacement of fossil fuels with renewable ones. Radiocarbon analysis through accelerator mass spectrometry could meet this challenge, and could even enable the creation of a biofraction certification for products to support the bioeconomy.
Radiocarbon Analytics Finland RACAF
RACAF is an organisation operated jointly by the University of Helsinki’s Finnish Museum of Natural History Luomus and the Department of Physics at the Faculty of Science. It is engaged in biofraction determination research based on radiocarbon analysis, and offers related analysis services.
Luomus’ Laboratory of Chronology manages the analyses and handles the processing of samples. The radiocarbon determinations are conducted in the Accelerator Mass Spectrometer (AMS) at the Department of Physics. In the analyses, the TAMIA particle accelerator at the Department of Physics is used as an extremely sensitive mass spectrometer to determine the concentration of radiocarbon. The University’s AMS equipment is among the best of its kind in the world, and it is supremely suited for the biofraction determination of fuels. The University’s processes for 14C determination are currently being accredited.
+358 50 3187 301
Head of Unit, Docent
Finnish Museum of Natural History Luomus
+358 50 3187 302
Postdoctoral Researcher, Docent
Department of Physics
+358 2941 50010