Use of nickel-tube pyrolysis for hydrogen-isotope analysis of water and other compounds

Addition of a simple evacuated collection device to nickel-tube pyrolysis bombs permits collection of the hydrogen gas produced during decomposition of water and other substances containing hydrogen. Tests using water samples spanning a broad range of H-2/H-1 ratios show that the method can be readily calibrated to yield precision comparable to that of the widely used zinc-reduction method. Preliminary results from pyrolysis of polyethylene foil, insect chitin, wood cellulose, peptide, and biotite mica (bound water) suggest that this modification of the nickel pyrolysis technique may have broad application, especially where both oxygen- and hydrogen-isotope compositions of the material are of interest. (C) 1997 Elsevier Science B.V.