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An Improved Procedure for Wet Oxidation of the 14C Nbs Oxalic Acid Standard

  • S Valastro (a1), L S Land (a2) and A G Varela (a1)

Abstract

An improved procedure for wet combustion of 14C NBS oxalic acid standard has been devised which gives consistent high carbon yields and average δ13C values of —19.1‰. The principal cause of fractionation in earlier attempts to prepare CO2 by the wet oxidation method was the inexact nature of the end-point. The new procedure employs a chocolate-brown end-point by adding 5ml more of the sulfuric acid-potassium permanganate solution after the initial reddish brown end-point is reached. The sulfuric acid-potassium permanganate solution is added to the NBS oxalic acid in a steady drop-wise flow, heat is applied to the generating apparatus, and a cycling technique is utilized to collect the CO2.

Fifteen samples of the NBS oxalic acid were processed. The per cent carbon yields range from 98.8 to 100.9% with an average of 99.7% and an average δ13C of —19.12‰. The results obtained by this procedure are much more consistent than previous results obtained in several laboratories by direct combustion.

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References

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Bernestein, R B, 1957, Simple laboratory method producing enriched carbon-13: Science, v 126, p 119120.
Broecker, W S and Olson, E A, 1961, Lamont radiocarbon measurements VIII: Radiocarbon, v 3, p 176204.
Craig, Harmon, 1961, Mass-spectrometer analyses of radiocarbon standards: Radiocarbon, v 3, p 13.
Grey, D C, Damon, P E, Haynes, C V, and Long, Austin, 1969, Carbon-isotope fractionation during wet oxidation of oxalic acid: Radiocarbon, v 11, p 12.
Hubbs, C L and Bein, G S, 1967, La Jolla natural radiocarbon measurements V: Radiocarbon, v 9, p 261.
Kim, S M, 1970, Wet oxidation of oxalic acid used in radiocarbon dating and 14C fractionation during the oxidation: Doehan Hwahak Hwejee (Korean Chem Soc Jour), v 14, no. 1, p 4950.
Kolthoff, M I and Sandell, E B, 1952, Textbook of quantitative inorganic analysis: New York, The McMillan Co, p 564.
Lindsay, J G, McElcheran, P E, and Thode, H G, 1949, The isotope effect in the decomposition of oxalic acid: Chem Phys Jour, v 17, p 489.
Noakes, J E, Kim, S M, and Akers, L, 1967, Recent improvements in benzene chemistry for radiocarbon dating: Geochim et Cosmochim Acta, v 31, p 10941098.
Polach, H A, 1972, Cross-checking of NBS oxalic acid and secondary laboratory radiocarbon dating standards: 8th internatl conf on radiocarbon dating, Proc, Royal Soc of New Zealand, v 2, H92-H120.
Polach, H A and Krueger, H A, 1972, Isotopic fraction of NBS oxalic acid and ANU-sucrose radiocarbon dating standards: 8th internatl conf on radiocarbon dating, Proc, Royal Soc of New Zealand, v 2, p H121-H128.
Tamers, M A, 1965, Routine carbon-dating using liquid scintillation: 6th internatl conf on radiocarbon and tritium dating, Proc, Clearing House for federal sci and tech info, U S Dept Commerce, p 5367.

An Improved Procedure for Wet Oxidation of the 14C Nbs Oxalic Acid Standard

  • S Valastro (a1), L S Land (a2) and A G Varela (a1)

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