ISSN:
1089-7623
Source:
AIP Digital Archive
Topics:
Physics
,
Electrical Engineering, Measurement and Control Technology
Notes:
The lignin content of wood, paper, pulp, or other materials containing lignin (such as filter paper soaked in black liquor) is readily determined by flash pyrolysis of the sample at approximately 550 °C in a reducing atmosphere of hydrogen or in an inert atmosphere of helium followed by a rapid analysis of the product gas by a mass spectrometer. The heated pyrolysis unit as fabricated, comprises a small platinum cup welded to an electrically heated stainless-steel ribbon with control units for programmed short duration (1.5 s, approximately) heating and for continuous flow of hydrogen or helium. The pyrolysis products enter an electron-ionization-mode mass spectrometer for spectral evaluation. Lignin content is obtained from certain ratios of integrated ion currents of many mass spectral lines, the ratios being linearly related to the Kappa number or Klason lignin. The Kappa number can be obtained from a few milligram sample in 3 min which is at least ten times faster than a Kappa number determination by the Standard Chemical Method. The present instrument can measure Kappa numbers in the whole range from 0 to 200 without any readjustments.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.1141402
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