PYROLYSIS DERIVATIZATION OF HUMIC SUBSTANCES .1. PYROLYSIS OF FULVIC-ACIDS IN THE PRESENCE OF TETRAMETHYLAMMONIUM HYDROXIDE

Pyrograms of three fulvic acids (FAs) of different origins and the corresponding pyrograms obtained by reactive pyrolysis with tetramethylammonium hydroxide (TMAH) are compared. This procedure introduces both striking qualitative and quantitative changes in the pyrolytic patterns of the FAs, which are discussed in terms of the usefulness of this approach to structural studies. Some non-pyrolysis compounds (probably retained in the macromolecular fulvic matrix) seem to be released when the FAs are pyrolysed in the presence of TMAH. A set of benzenecarboxylic acid standards was also pyrolysed both in the absence and in the presence of TMAH. The results obtained suggest a thermally assisted chemolysis rather than in situ methylation of the pyrolysis products.