Klason Lignin: Modifications to Improve the Precision of the Standardized Determination

Abstract

Summary The lignin content in wood is generally determined with a standardized method. It is shown that with minor modifications, e.g., particle size, temperature and adherence to handling times, the standard deviation could be decreased substantially. Pooled standard deviations of 0.045 %, based on 30 determinations in immediate succession, and 0.11%, based on 400 determinations in randomized order, were obtained, which are well qualified for the calibration of secondary analytical methods such as NIR or Raman spectrometry. As a consequence of finer grinding, an identical sample can be used for lignin determination and for investigations in the mid infrared region without regrinding or fractionating.