Characterization of impurities in pulp and paper products using pyrolysis—gas chromatography/mass spectrometry, including direct methylation☆

Abstract The organic impurities found in pulps and paper products and as deposits on equipment in pulp and paper mills can be rapidly characterized using pyrolysis—gas chromatography/ mass spectrometry (Py—GC/MS). Frequent problems arise from resin and sizing agents, which contain polar compounds. These products, which have difficulty in passing through the Py—GC system, can be methylated directly on the pyrolysis filament by the addition of tetramethylammonium hydroxide. The possibility of distinguishing between wood resin and different sizing agents including rosin, fortified rosin and alkylketene dimers, is demonstrated. Some examples in which the described technique is used for characterizing impurities are also given.