抄録
High resolution NMR spectroscopy and other physical methods have been used for the study of the chemical structure of coal with the aid of chemical ultimate analysis by the conventional combustion method (JIS) and pyrolysis. However, a more precise ultimate analysis with special reference to oxygen is necessary in order to obtain a truly accurate determination of the chemical structure of coal. In the present report, a discussion was made on the precision of the fast neutron activation analysis for the determination of oxygen content of high pressure coal hydrogenolysis products. The following conclusionswere obtained.
(1) A relative error of 2% was achieved by the present neutron activation analysis using gold as the internal standard and solid paraffine and graphite as diluents. It was demonstrated that the method is applicable in the determination of more than 0.2mg of oxygen in a sample of 200mg.
(2) The relative error of the pyrolysis method was found to be 1-9% depending on the level of oxygen content in the samples. This method is applicable to samples containing more than 1.0% of oxygen.
(3) Oxygen content determined indirectly by the combustion method results in a generally overestimation because of incomplete combustion of the samples used in our present work.
