On-line D/H analysis for water, natural gas, and organic solvents by manganese reduction

A new technique for on-line sample preparation and D/H determination is described. The technique is suitable for the preparation of fresh and brine waters, as well as natural gases and organic solvents. A 5-microL sample of water or hydrogen equivalent is injected and reduced by means of hot manganese metal in a specially designed reaction tube surrounded by a tube furnace and attached directly to the mass spectrometer inlet without modification.The hydrogen gas flows directly into the MS to be analyzed by reference/sample comparison. The reproducibility varied between 0.7 and 1.8% for all liquid and gas samples. The accuracy of this technique is confirmed by analysis of IAEA standard waters V-SMOW, GISP, and SLAP, as well as NGS-3 (IAEA methane intercomparison material).