Abstract

Abstract In order to elucidate the main reactions of ozone with residual lignins in softwood kraft pulps, model compounds representing conjugated structures (styrenes and stilbenes) and structures of the biaryl, diary] ether and diarylmethane types have been treated with this oxidant. The oxidation mixtures were analyzed using HPLC and GC techniques and the main components were identified by 'H NMR and mass spectrometry. Formation of the degradation products is interpretod in terms of known mechanisms of ozonation. A comparison between the reaction rates reveals that the structural types studied in this work can be arranged according to their ease of ozonation in the following order: stilbenes > stv-renes > phenolic structures > muconic acid type intermediates (from the opening of aromatic rings) > non-phenolic structures >> aromatic aldehydes (from the degradation of conjugated structures). The advantages connected with the use of ozone as deligni-fying reagent are briefly discussed in the light of the r...

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.