Development of graphitization method for low carbon aerosol filter samples with Automated Graphitization System AGE-3. (December 2022)

• Record Type: Journal Article
• Authors: Butkus, Laurynas; Šapolaitė, Justina; Garbarienė, Inga; Garbaras, Andrius; Bučinskas, Laurynas; Pabedinskas, Algirdas; Remeikis, Vidmantas; Ežerinskis, Žilvinas
• Is Part Of: Applied radiation and isotopes. Volume 190(2022)
• Publication Date: 2022-12
• Subjects: low Carbon samples -- AGE-3 -- Sample dilution -- Mass balance equation -- Radiocarbon -- 14C; Radiology -- Periodicals; Radiation -- Industrial applications -- Periodicals; Nuclear chemistry -- Periodicals; Internet resource; Periodical; 660.298
• DOI: 10.1016/j.apradiso.2022.110461
• Languages: English
• ISSNs: 0969-8043

Abstract

Abstract: The wide applications of the radiocarbon ( 14 C) approach in environmental, archeological, and geological research often necessitates the analysis of microgram-sized samples. The ability to measure low carbon samples is particularly relevant for aerosol particle filters, especially for samples from pristine environments. For this purpose, we investigated the sample dilution method for graphitization of low-carbon samples (20–200 μg C) with an Automated Graphitization System (AGE-3), and applied a mass balance equation for the calculation of 14 C values. Materials with known 14 C values (standards NIST-OXII and IAEA-C7) were diluted with 14 C-free phthalic anhydride (PhA) until sufficient mass (500 μg C) for graphitization with the AGE-3 system was acquired. Reliable 14 C values were obtained for samples with carbon amount in the range of 40–200 μg. Next, we adapted the dilution method for estimation of aerosol sample 14 C values. Using it, we attained a precision of 0.71 ± 0.83 pMC for 14 C measurements of aerosol samples containing 40–200 μg C. A shift of radiocarbon values to 5.07 pMC (average 3.08 ± 1.7 pMC) was observed for samples with low carbon content (<20 μg C). We determined that a precision of 2–3 pMC is acceptable for aerosol particle source apportionment studies. Using the sample dilution method, graphitization with AGE-3 of aerosol samples with carbon content >40 μg becomes a viable and efficient way of sample preparation for 14 C analysis. Highlights: Dilution method was aplied for graphitization of low-carbon samples. Reliable 14 C values were obtained for samples with carbon amount in the range of 40–200 μg. The sample dilution method for graphitization of aerosol samples becomes a viable way of sample preparation for 14 C analysis. The dilution method is suitable for low-carbon aerosol filters, which are relevant in aerosol source apportionment studies.