The effect of peroxymonosulphate (oxone) as an acting agent in the delignification of sisal and jute has been studied. Conditions were varied in the following ranges: Oxone0-200 g/L and temperature 30-100°. Delignification was followed, by extraction with 1 M NaOH, The residues were analyzed, both before and after alkali extraction for lignin and residual sugar composition and their diffuse reflectance Fourier-transform infrared (DRFIT) spectra were acquired. Treatment in the absence of Oxone(acid alone) removed some pectic-linked lignin fragments. The presence of Oxone, however, resulted in a net removal of glucuronoxylan and rhamnogalacturonan II. At moderate Oxone concentration and temperature, e.g., 50 g/L, 700, residual lignin contents were reduced significantly (80%). This was confirmed by DRFIT spectroscopy. Alkali extraction of Oxonetreated residues reduced, without exception, the residual lignin contents, some to as low as 98% of the original level. The removal of non-cellulosic polysaccharides, with the exception of glucomannan, was directly related to temperature and Oxone concentration. Evidence was found, suggesting that at least portions of the arabinose and galactose residues were linked to lignin. The bleaching ability exhibited a direct relationship to temperature and Oxoneconcentration, and acceptable levels of brightness were achieved at moderate temperature (700) and Oxone concentration (5 g/L).
|Number of pages||13|
|Journal||Cellulose Chemistry and Technology|
|Publication status||Published - 2000|
- natural fiber
- operating conditions
- experimental study